WHO Advisory Committee on serological responses to ...• all cause hospital admissions in the first year of life by 23% (95% CI: 10.0%; 34.0%) (noting that admissions were not, however,

WHO Advisory Committee on serological responses to Expanded Programme on Immunization vaccines in infants receiving Intermittent Preventive Treatment for malaria (IPTi)

FINAL REPORT

October 8, 2009

Contents

Executive summary ...........................................................................................................1

Background ..............................................................................................................3

EPI Serology Study Design...............................................................................................5

Study sites and study population .................................................................................5

Study design ..............................................................................................................6

WHO Advisory Committee .......................................................................................11

Results – Pooled Analysis ...............................................................................................12

Pooled SP vs Placebo comparison for measles: ........................................................12

Pooled drugs (SP, LapDap, SP-ART, AQ-ART, MQ) vs placebo comparison for

measles ............................................................................................................13

Pooled Analysis for other antigens............................................................................15

Results – Yellow Fever (Navrongo) ...............................................................................16

Conclusions of the WHO Advisory Committee............................................................18

Annex 1: Report of the Technical Consultation on Intermittent Preventive

Treatment in Infants (IPTi), Technical Expert Group (TEG) on Preventive

Chemotherapy, April 23-24, 2009 Geneva.. ..........................................................19

Annex 2: Membership of WHO Advisory Committee on serological responses to

Expanded Programme on Immunization vaccines in infants receiving

Intermittent Preventive Treatment for malaria...................................................20

Annex 3: Final Pooled Analysis: Assessment of Serological Responses to Expanded

Programme on Immunization Vaccines in Infants Receiving Intermittent

Preventive Treatment (v.3 submitted July 3, 2009) .............................................21

Annex 4: Summaries of Individual Study Results .......................................................22

Navrongo, Ghana.......................................................................................................22

Manhiça, Mozambique ..............................................................................................24

Bungoma, Kenya .......................................................................................................26

Kisumu, Kenya ..........................................................................................................29

Kilimanjaro, Tanzania ...............................................................................................32

1

Executive summary

Intermittent Preventive Treatment in infants (IPTi) is the administration of a full course

of an antimalarial treatment to infants at specified time points, regardless of the presence

of parasites. The objective of IPTi is to reduce the infant malaria burden in the first year

of life. Administering IPTi at the time of routine immunization is proposed to be the main

delivery strategy. It is therefore of critical importance to confirm that IPTi does not have

any adverse interaction with the serological responses to EPI vaccines.

As a partner of the IPTi Consortium, and with funding from the Bill & Melinda Gates

Foundation, WHO undertook serology assessments in five IPTi efficacy trials conducted

in Ghana (Navrongo), Kenya (Bungoma and Kisumu), Mozambique (Manhica), and

Tanzania (Kilimanjaro). Infants eligible for the serology studies were selected from the

larger study population at each site.

To oversee and guide this work, in 2003 WHO established a 5-member, independent Ad

Hoc Advisory Committee (see Annex 2 for Terms of Reference and Membership). The

Advisory Committee assisted with the design of the project, selection of the sub-

contractors, and review of all the data arising from five EPI serology studies. The

Advisory Committee guided WHO accordingly, and issued an Interim Report in July

2006. The Interim Report, based on data at the time from the Navrongo (Ghana), Manhica

(Mozambique) and Bungoma (Kenya) studies, concluded that IPTi-SP did not have an

adverse impact on serological responses to vaccination against measles, diphtheria,

tetanus, pertussis, polio serotypes 1 and 3, Haemophilus influenzae type b and hepatitis B.

The studies using other drug combinations and analysis of all the samples have now been

completed and reviewed. This Final Report of the Advisory Committee describes the

methodology of the IPTi serology studies, summarizes the results of the pooled statistical

analysis, and presents the Advisory Committee's final conclusions based on a compilation

of all the data available. The report is primarily based on the final pooled analysis of the

results, and supported by selected analyses of the individual trials where no pooled

analyses were planned (i.e. yellow fever and Hib vaccines).

While it cannot be held responsible for the conduct of the field trials or laboratory work,

the Advisory Committee concludes the following:

1. Serological data from studies in Navrongo, Manhica, and Kilmanjaro provide strong

evidence that IPTi with SP, does not have an adverse impact on serological responses

to measles vaccine;

2. Though very limited, the available serological data from Navrongo provides evidence

that SP does not have a negative impact on antibodies following vaccination against

yellow fever;

3. Serological data from studies in Kisumu and Kilimanjaro provide strong evidence

that IPTi with SP-ART, AQ-ART, MQ, or LapDap do not have an adverse impact on

serological responses to measles vaccination;

2

4. Serological data from Manhica and Kisumu provide strong evidence that IPTi with

SP, SP-ART, AQ-ART, or LapDap do not have an adverse impact on serological

responses to DTP, polio, Hib, and HepB vaccines.

5. The pooled analyses provide further evidence that IPTi treatments do not impair

serological responses to EPI antigens.

Overall conclusion:

Studies have demonstrated that there is no adverse impact on the serological responses to

DTP, polio, Hib, HepB, and measles vaccines when the IPTi drugs SP, SP-ART, AQ-

ART, and LapDap are administered to infants at the time of routine vaccination.

Concomitant administration of IPTi-SP at the time of yellow fever vaccination, and IPTi-

MQ at the time of measles vaccination, have also been shown to have no negative effect

on the serological responses.

3

Background

Intermittent Preventive Treatment in infants (IPTi), is the administration of a full course

of an antimalarial treatment to infants at specified time points, regardless of the presence

of parasites. The objective of IPTi is to reduce the infant malaria burden in the first year

of life. Administering IPTi at the time of routine immunization is one of the delivery

strategies.

Over the past 10 years, IPTi has been the focus of a number of research efforts. With

funding from the Bill & Melinda Gates Foundation, in 2002 the IPTi Consortium (a

collaboration of 17 research institutions plus WHO and UNICEF) was formed to

undertake a coordinated and comprehensive research agenda on IPTi in order to inform

policy development1. This has included clinical trials in southern-African countries

(Gabon, Ghana, Kenya, Tanzania, Mozambique) and large-scale pilot implementation

studies involving over 300,000 infants a year in districts of Benin, Ghana, Madagascar,

Mali, Malawi, Tanzania, and Senegal.

The available evidence on the safety, efficacy and other relevant aspects of IPTi with

sulfadoxine-pyrimethamine (SP-IPTi) delivered through the Expanded Programme on

Immunization (EPI) has been reviewed independently in 2008 by the Institute of

Medicine (IOM)2 and three times by WHO's Technical Expert Group (TEG) on

Preventive Chemotherapy3 most recently in April 2009 (Annex 1).

On the basis of a pooled analysis of 6 published studies4, IPTi-SP was found to be safe

and decreased:

• incidence of clinical malaria episodes by 30% (95% CI: 19.8%; 39.4%) (similar to

the levels of efficacy observed with the use of insecticide-treated bednets);

• anaemia (<8g/dl) overall by 21.3% (95% CI: 8.3%; 32.5%);

• all cause hospital admissions in the first year of life by 23% (95% CI: 10.0%; 34.0%)

(noting that admissions were not, however, all due to severe malaria).

1 See web site: www.ipti-malaria.org and IPTi Fact Sheet (Feb. 2009) for more information.

2 Institute of Medicine. Assessment of the Role of Intermittent Preventive Treatment for Malaria in

Infants: Letter Report. Committee on the Perspectives on the Role of Intermittent Preventive

Treatment for Malaria in Infants, July 11, 2008.

(http://www.iom.edu/CMS/3783/48783/56178,aspx)

3 WHO. Report of the Technical Consultation on Intermittent Preventive Treatment in Infants (IPTi),

Technical Expert Group (TEG) on Preventive Chemotherapy, April 23-24, 2009 Geneva. (Annex 1).

4 Aponte, John. J, Schellenberg, David, et al. Intermittent Preventive Treatment for Malaria Control in

African Infants: Pooled analysis of safety and efficacy in six randomized controlled trials. Accepted for

publication by Lancet 2009, forthcoming.

4

Both the IOM and WHO's TEG have recommended that IPTi-SP be considered for

implementation through EPI as an additional malaria control intervention in countries in

Africa south of the Sahara with moderate to high malaria transmission, and where drug

resistance to SP is low.

As part of the IPTi Consortium research to support this policy recommendation, since

2002 WHO has been coordinating a project designed to investigate the impact of IPTi

with SP and a range of other antimalarial drugs5 on infant serological responses to EPI

vaccines. Confirmation that IPTi does not have any adverse interaction with the

serological responses to vaccination was critical to ensuring that EPI could safely be used

as the delivery mechanism for IPTi. Early results from the first IPTi-SP trial in Ifakara,

Tanzania6 raised concerns that seropositivity to measles and pertussis vaccines was lower

in infants receiving IPTi compared to placebo.

To oversee and guide this area of work, WHO established a 5-member, independent Ad

Hoc Advisory Committee (see Annex 2 for Terms of Reference and Membership). The

Advisory Committee assisted with the design of the project, selection of the sub-

contractors, and review of all the data arising from five EPI serology studies. The

Advisory Committee guided WHO accordingly, and issued an Interim Report in July

20067. The Interim Report, based on data at the time from the Navrongo (Ghana),

Manhica (Mozambique) and Bungoma (Kenya) studies, concluded that IPTi-SP did not

have an adverse impact on serological responses to vaccination against measles,

diphtheria, tetanus, pertussis, polio serotypes 1 and 3, Haemophilus influenzae type b and

hepatitis B.

This Final Report of the Advisory Committee describes the methodology of the IPTi

serology studies, summarizes the results of the pooled statistical analysis, and presents the

Advisory Committee's final conclusions based on all the data available.

5 See Table 1 for list of drugs studied and their abbreviations in the footnote of the table.

6 Schellenberg, D. et al. (2001). Intermittent treatment for malaria and anaemia control at time of routine

vaccinations in Tanzanian infants: a randomized, placebo-controlled trial. Lancet, 357: 1471-1477.

7 The Interim Report summarized the results as of 2006 from Navrongo, Manhica and Bungoma, a pooled

analysis of Navrongo and Manhica data, and the conclusions of the Advisory Committee. This Final

Report includes all data from all trials and as such supercedes the analysis of the Interim Report.

5

EPI Serology Study Design

Study sites and study population

The EPI serology work was designed as "nested sub-studies" within five randomized

controlled studies of the IPTi Consortium and one other on-going trial to assess the

protective efficacy of IPTi against episodes of clinical malaria and anemia. The EPI

serology assessments were included in the IPTi trials conducted in Ghana (Navrongo)8,

Kenya (Bungoma9 and Kisumu), Mozambique (Manhica), and Tanzania (Kilimanjaro).

Infants eligible for the serology studies were selected10

from the larger study population

at each site.

Infants were randomized into: i) placebo or SP in Navrongo, Manhica and Bungoma, ii)

placebo, SP-ART, AQ-ART and LapDap in Kisumu and iii) placebo, SP, MQ and

LapDap in Kilimanjaro. All sites performed serological testing for measles vaccine. Only

Navrongo undertook serological assessment for yellow fever vaccine. Bungoma,

Manhica, and Kisumu performed serological testing on all other antigens.

Table 1 summarizes the specific details of each of the serological studies – including the

drugs used, the IPTi dosing schedule, sample size, timing of blood samples, and EPI

antigens assessed.

In each of the serological studies, IPTi (using a number of antimalarial drug options) or

placebo was administered on three occasions11

during the first year of life at the time of

routine EPI vaccination (doses 2 and 3 of diphtheria, tetanus and pertussis (DTP); and

measles vaccination). Detailed information was obtained on the vaccination status

(including BCG and birth doses of polio) of each infant recruited to the serology studies.

8 Note: The Navrongo study was nearly completed when the protocol for the EPI serology studies was

designed. Since Navrongo provided a unique opportunity to obtain information on serological

responses to yellow fever vaccination, a decision was made to retrospectively measure the serological

responses on a selection of blood samples already taken.

9 This trial was supported by WHO/TDR and not part of the IPTi Consortium.

10 Notes on sample selection: Navrongo: As this trial was already completed, the EPI serology

study used stored samples. Those children with pre and post vaccination paired samples of

sufficient volume were selected. Bungoma: Samples from all children in the study were used unless

there was insufficient volume or sample was not taken. Kisumu: This study was designed with a

sample size of 379 per arm at the beginning. When the serology study was proposed the trial was

unable to increase the sample size to 500 per arm for budgetary and operational reasons. The

serology study used samples collected from all children unless the sample was of insufficient

volume or missed. Manhica: The trial was underway before the EPI serology study was developed.

Serological responses to EPI vaccines were assessed in a subsample of study infants consecutively

selected as they came to the clinic until the estimated sample size of 300 children per arm (for the

main trial) was completed.

11 The Navrongo trial included a fourth dose of IPTi at 12 months of age which was not linked with EPI.

6

All studies were approved by the relevant local and international (including WHO)

Ethical Review Boards. Written informed consent was obtained from the parents or

guardians of all participating infants.12

Study design

The serological assessments were designed as non-inferiority studies, with the objective

to demonstrate that IPTi does not reduce serological responses to EPI vaccines by more

than a proportion deemed to be clinically important.

Primary endpoint: The primary endpoint was serological responses to measles vaccine. If

the proportion of infants attaining protective levels (> 120IU/L) of measles antibody post-

vaccination was reduced by ≤ 5% in the IPTi group compared to the placebo group, it

would not be considered that IPTi had an adverse impact on serological responses to

measles. The sample size of 50013

per arm was calculated with the aim of rejecting, with

80% power and a one-sided significance level of 5%, the null hypothesis that the

difference between the groups was > 5%.

Secondary endpoints: The secondary endpoints were serological responses to all other

EPI vaccines. If the proportion of infants attaining protective levels (see Table 3) of

antibody post-vaccination was reduced by ≤ 10% in the IPTi group compared to the

placebo group, it would not be considered that IPTi had an adverse impact on serological

responses to EPI vaccines. The sample size of 250 per arm was calculated with the aim of

rejecting, with 80% power and a one-sided significance level of 5%, the null hypothesis

that the difference between the groups was > 10%.

Plotting of reverse cumulative distribution functions (RCDF) of the proportion of infants

attaining different antibody titres was an important graphic tool for visualizing the full

distribution of data and comparison of results. Close agreement of RCDFs from infants

given IPTi with those given placebo supports the conclusion that antibody responses are

similar in the two populations over the full range of antibody concentrations. Post-

vaccination geometric mean concentrations in the treatment and placebo groups were

compared.

12 See Annex 4 page 27 for details about Bungoma trial having to re-do written consent retrospectively. 13 At the outset the Kisumu sample size was planned to be less (379) because they knew it was not possible to

obtain a target of 500 before the conclusion of the trial.

7

Table 1. IPTi studies that include assessment of serological responses to EPI vaccines

Study site

Study

design

Drug(s)

for IPTi

Age at IPTi drug dosing

Sample size

EPI immunization schedule

Timing of

blood samples

Serological information

available from each

study

Navrongo,

Ghana

RCT

SP

Placebo

10 weeks (DTP2)

14 weeks (DTP3)

9 months (measles)

12 months

500 SP

500 placebo

BCG: birth

DTP, hepB, Hib: 6, 10, 14

weeks

Polio: birth, 6, 10, 14 weeks

Measles, yellow fever: 9

months

9 months

12 months

Measles, yellow fever

Bungoma,

Kenya

RCT

SP

Placebo

10 weeks (DTP2)

14 weeks (DTP3)

9 months (measles)

500 SP

500 placebo

BCG: birth

DTP, hepB, Hib: 6, 10, 14

weeks


Measles: 9 months

6 weeks

18 weeks

9 months

10 months

DTP, polio, hepatitis B,

Hib, measles

8

Manhica,

Mozambique

RCT

SP

Placebo

12 weeks (DTP2)

16 weeks (DTP3)

9 months (measles)

500 SP

500 placebo

BCG: birth

DTP, hepB: 8, 12, 16 weeks


Measles: 9 months

20 weeks

9 months

12 months

DTP, polio, hepatitis B

measles

Kisumu, Kenya

RCT SP-ART

AQ-ART

LapDap

Placebo

10 weeks (DTP2)

14 weeks (DTP3)

9 months (measles)

379 x 3 intervention

379 placebo

As for Bungoma

6 weeks

18 weeks

9 months

12 months

DTP, polio, hepatitis B,

Hib, measles

Kilimanjaro,

Tanzania

RCT

SP

MQ

LapDap

Placebo

8 weeks (DTP2)

12 weeks (DTP3)

9 months (measles)

500 x 3 intervention

500 placebo

BCG: birth

DTP, hepB: 4, 8, 12 weeks


Measles: 9 months

9 months

10 months

Measles

Legend: RCT: randomised controlled trial; SP: sulfadoxine-pyrimethamine; SP-ART: sulfadoxine-pyrimethamine plus artesunate; MQ: mefloquine; LapDap: chlorproguanil-

dapsone; AQ-ART: amodiaquine plus artesunate; DTP: diphtheria, tetanus, pertussis; hepB: hepatitis B; Hib: Haemophilus influenzae type b

9

It was planned that each study site would attain the requisite sample size for the primary and

secondary endpoints, and that data from all sites be pooled to provide overall summary

measures of even greater precision.

Blood sampling: A minimum of 0.5mls of whole blood was taken by finger prick or venous

sampling at intervals indicated in Table 2. Samples were centrifuged, and sera frozen at

minus 20 degrees Centigrade.

Serological assays: Following a tendering process, the WHO Advisory Committee assessed

quotations from four internationally recognized public health reference laboratories for

carrying out the serological assays for these studies. The Health Protection Agency (HPA),

UK, was chosen on the basis of its competitive pricing, expertise in functional (plaque

reduction neutralization) assays, and capacity to deal with large numbers of samples within

the requisite timeframe. The laboratory was blind to the allocation status (IPTi or placebo)

of all samples. Geometric Mean Titres (GMTs) were measured by plaque reduction

neutralization (measles and yellow fever), microneutralization (polio serotypes 1 and 3) and

enzyme linked immunosorbent assay (ELISA - all other EPI antigens). All assays were run

in duplicate, using standardized reagents or validated test kits. For measles and yellow fever,

pre-vaccination blood samples were assayed to check whether subjects had been exposed to

these diseases prior to vaccination. For all other EPI antigens, measurement was confined to

the post-vaccination blood sample14

. In instances where there was insufficient blood to carry

out all of the assessments, assays were carried out in the following order:

18–20 week sample

i. Haemophilus influenzae type b

ii. Diphtheria

iii. Polio serotype 3

iv. Hepatitis B

v. Pertussis toxin

vi. Tetanus

vii. Polio serotype 1

viii. Pertussis filamentous haemagglutinin

10–12 month sample

i. Measles

ii. Yellow fever

14 Pre-vaccination samples were collected, but as these were likely to contain maternal antibodies they were

stored in the event that that the post-vaccination results were equivocal and analysis of the pre-vaccination

samples was needed.

10

Table 2. Serological assays

Vaccine Pre or post-

vaccination

sample

Timing of blood

samples

Type of test Protective level

Measles

Pre

9 months Plaque reduction

neutralisation (PRN) 1-2

dilutions

To check for presence

of measles antibodies

pre-vaccination

Post 10 months or 12

months

PRN 6 dilutions (GMT) 120 IU/l

Yellow fever Pre 9 months PRN 1-2 dilutions To check for presence

of YF antibodies pre-

vaccination

Post 10 months or 12

months

PRN 6 dilutions (GMT) 1:5 (PRN titre)

Diphtheria Pre At time of DTP1 Store in freezer*

Post One month post

DTP3

Quantitative ELISA

(GMT)

0.1 IU/ml

Tetanus Pre At time of DTP1 Store in freezer*

Post One month post

DTP3

Quantitative ELISA

(GMT)

0.1 IU/ml

Pertussis (PT and

FHA only)

Pre At time of DTP1 Store in freezer*

Post One month post

DTP3

Quantitative ELISA

(GMT)

Protective levels not

defined

Polio (serotypes 1

and 3 only)


Post One month post

DTP3


Haemophilus

influenzae type b


Post One month post

DTP3

Quantitative ELISA

(GMT)

0.15 µg/ml (1.0 µg/ml

will be used as a

secondary descriptive)

Hepatitis B Pre At time of DTP1 Store in freezer*

Post One month post

DTP3

Quantitative ELISA

(GMT)

10 IU/l

* Pre-vaccination GMTs will only be obtained if the post-vaccination results are equivocal; PRN: Plaque reduction neutralisation; GMT: Geometric mean titre; PT: Pertussis toxin; FHA: Filamentous haemagglutinin

11

This ranking was based on the relative immunogenicity of each antigen, with those of lower

immunogenicity being assigned a higher rank, so as to increase the likelihood of detection of

any potential interference. Haemophilus influenzae type b (Hib) was assigned top rank since

regulatory authorities are particularly concerned about serological responses to Hib vaccine.

Interference with responses to this vaccine have been demonstrated in different settings,

particularly in relation to fever15

.

Any infants failing to attain protective levels of antibody post-vaccination were offered

revaccination.

Statistical analysis: A competitive tender was won by the London School of Tropical

Medicine and Hygiene (LSHTM) Tropical Epidemiology Group. LSHTM was sent the

results of all the laboratory serology, relevant clinical data from each study site plus the

randomization codes. Post-vaccination geometric mean antibody concentrations (GMCs)

and the proportion of infants attaining the protective level for each EPI antigen were

compared in the IPTi and placebo groups. Reverse cumulative curves were plotted for each

EPI antigen.

The results for each of the trials are provided in individual statistical reports for each study.

These final reports are on file with WHO and have been shared with the study teams for

inclusion in the publication of their trial results.

A final pooled analysis of all the study results was prepared in early 2009. Data from the

trial in Bungoma were excluded due to previously established concerns about data quality.

The final pooled analysis (March 27, 2009) that was accepted by the Advisory Committee is

provided in Annex 3.

WHO Advisory Committee

The Committee met several times over the course of this project, particularly in 2003 to

advise on the design of the protocol and selection of the laboratory. In later years, the

Committee has used teleconferences to conduct its work (See Annex 2 for complete listing

of dates of meetings and teleconferences).

The Advisory Committee reviewed and discussed each of the statistical reports of the five

studies. Often the Committee requested revisions or additional statistical analyses in order to

facilitate their interpretation and conclusions. A complete record of the minutes of these

teleconference is on file with WHO. Brief summaries of the results for each of the five

studies can be found in Annex 4.

Prior to issuing their final conclusions, the Advisory Committee requested an independent

audit of the laboratory work carried out by HPA. A post study audit was performed on the

laboratory records in Jan and March 2009. Several discrepancies were noted and HPA was

requested to take corrective action on these points. Subsequently, a second follow-up audit

was conducted in June 2009 with the objective to further investigate the discrepancies noted

in the first audit and to evaluate the corrective actions taken. Overall, the HPA labs were

15 Usen S, Milligan P, Ethevenaux C, Greenwood B, Mulholland K. Effect of fever on the serum

antibody response of Gambian children to Haemophilus influenzae type b conjugate vaccine. Pediatr

Infect Dis J 2000;19(5):444-9.

12

found to be operating in a manner that meets relevant GLP criteria for this GCP study. The

audit satisfied the Advisory Committee that the analyses were carried out appropriately.

This Final Report presents the final conclusions of the Advisory Committee and is primarily

based on the final pooled analysis of the results, and supported by selected analyses of the

individual trials where no pooled analyses was planned (i.e. yellow fever and Hib vaccines).

Results – Pooled Analysis

The pooled analysis (see Annex 3 for full report) was conducted on data from four of the

study sites – Navrongo, Manhica, Kisumu, and Kilimanjaro. Data from the fifth trial,

conducted in Bungoma, was excluded due to concerns about data quality. Data from

different trials and treatment groups were pooled only after establishing, by means of

appropriate interaction tests, that treatment effects were not heterogeneous. If there was

evidence of heterogeneity, pooling was not done and trial-specific treatment effects were

reported.

Both Intention-to-Treat (ITT) and According-to-Protocol (ATP) analyses were undertaken.

All children with matched pre and post measles vaccination samples were included in the

ITT analysis. Children with incomplete drug dosing were excluded from the ATP analysis.

Hence, only Navrongo children with all four drug doses taken, and Manhica, Kisumu and

Kilmanjaro children with all three drug doses taken were considered for the ATP.

Separate analyses for measles were undertaken excluding children with: i) detectable and ii)

protective pre-vaccination levels. For all other antigens all children with a post vaccination

sample were included in the ITT analysis, whereas children with incomplete drug dosing

were excluded from the ATP analysis.

For all antigens analyses were conducted on post-vaccination antibody concentrations,

using: i) the continuous concentration variable, summarized by its geometric mean (GMC),

and ii) the binary protected/unprotected variable, based on whether antibody concentrations

were above or below the pre-defined threshold of protection for each antigen, where

appropriate.

Pooled SP vs Placebo comparison for measles:

Pooled data from Navrongo, Manhica and Kilmanjaro provided matched pre and post

vaccination measurements for 2,015 children (997 in placebo and 1,018 in SP groups).

Comparison of the geometric mean concentrations (GMC) for measles antibodies in the two

treatment groups before and after vaccination, as well as the median post-vaccination

concentration, found no evidence of a difference in the GMC between SP and placebo

groups in any of the sub-population investigations16

. (Annex 3)

The formal test of non-inferiority of the null hypothesis (that the difference in percentage

unprotected between groups was > 5%) gave strong evidence that SP is not inferior to

placebo in ITT and ATP analyses, excluding children with detectable/with protective pre-

vaccination concentration levels. For example, for the ATP analysis (excluding those

16 With and without detectable concentration pre-vaccination; with and without protective measles antibody level

pre-vaccination; all children.

13

children with detectable concentration at pre-vaccination) the actual difference (SP minus

placebo) between the groups was -0.15% with a 95% CI (-2.33, 2.04) (p<0.0001).

Finally, the reverse cumulative distribution function for measles antibody concentrations for

the ITT cohort (excluding children with detectable antibody levels at pre-vaccination),

shows that the curves for placebo and SP are nearly identical (Figure 1).

FIGURE 1: Pooled Analysis (Navrongo, Manhica, Kilimanjaro)

Reverse cumulative distribution function for measles antibody concentrations for the ITT

cohort excluding children with detectable antibody levels at pre-vaccination

0.2

.4.6

.81

1 2 3 4 5log(10) measles antibody concentration post-vaccination

Placebo SP

(vertical line indicates assumed protective threshold)

Reverse empirical cumulative distribution function

Pooled drugs (SP, LapDap, SP-ART, AQ-ART, MQ) vs placebo comparison for

measles

For the Kilimanjaro (SP+MQ+LapDap) measles comparison data were pooled for both

analyses, resulting in 397 children in placebo and 1,141 in the single combined treatment

group. No evidence was found to support a difference in the GMC between the combined

treatment group and placebo. The formal test of non-inferiority, gave strong evidence to

reject the null hypothesis that the proportion unprotected was at least 5% higher than in the

placebo group. The actual difference (combined treatment minus placebo) found in the ATP

analysis, excluding those with detectable concentration at pre-vaccination, was 0.21% with a

95% CI (-2.67, 3.08) (p=0.0001).

For the Kisumu (SP-ART+AQ-ART+LapDap) measles comparison, the treatment groups

were pooled for the analysis of GMCs, resulting in 284 children in placebo and 838 in the

combined treatment group. No evidence was found to support a difference in the measles

GMC between the combined treatment group and placebo. For the analysis of proportions

14

unprotected, however, the three treatment groups were heterogeneous (owing to the much

lower proportion unprotected in the LapDap group), so the three treatment groups were not

pooled (the separate analyses for the three treatment groups all rejected the null hypothesis

that the proportion unprotected is at least 5% higher than for placebo; see Annex 4).

A secondary pooled analysis of the Kisumu measles data excluding the LapDap group was

undertaken, to compare SP-ART + AQ-ART versus placebo. This strongly rejected the null

hypothesis that treatment is inferior to placebo.

A final pooled analysis for measles combining all treatment groups (except the Kisumu

LapDap group, for the reasons given above) versus placebo across the four trials (Navrongo,

Manhica, Kisumu and Kilimanjaro) resulted in 1,281 children in placebo and 2,363 in the

combined group. No evidence was found of a difference in the measles GMC between the

all combined treatment group and placebo. The formal test of non-inferiority (difference in

unprotected proportion of children is >5%), provided strong evidence that the combined

group was not inferior to placebo. For the ATP analysis, excluding those children with

detectable concentration at pre-vaccination, the actual difference (combined treatments

minus placebo) was 0.53% with a 95% CI (-1.18, 2.22) (p=0.0001).

The reverse cumulative distribution function of measles antibody concentrations for the ITT

cohort, excluding children with detectable pre-vaccination antibody levels ,provides

additional support that there is little difference between the intervention group (all

treatments except LapDap Kisumu) and placebo (Figure 2).

FIGURE 2: Pooled Analysis All Sites (Navrongo, Manhica, Kisumu and Kilimanjaro), All Treatments Combined (except Kisumu LapDap)

Reverse cumulative distribution function for measles for the ITT cohort excluding children with detectable antibody levels at pre-vaccination

0.2

.4.6

.81


Placebo Combined

(vertical line indicates assumed protective threshold)


15

Pooled Analysis for other antigens

Manhica (SP) and Kisumu (SP-ART, AQ-ART, LapDap) were the only sites assessing

antigens other than measles and yellow fever (polio types 1 & 3, diphtheria, tetanus,

hepatitis B, pertussis FHA & Toxin)17. Serology data for these antigens was available for a

total of 634 for the ITT and 567 for the ATP analysis. Complete data on all antigens was

available for 150 children.

The comparison of placebo groups in Manhica and Kisumu found that Kisumu had a

significantly higher percentage of unprotected children for polio types 1 & 3 and diphtheria

when compared to Manhica. For tetanus and HepB there was no evidence of a difference.

These results were the same in ITT, ATP, and other sub-population analyses. For diphtheria,

pertussis toxin and FHA, tetanus and HepB Manhica children had on average a higher

geometric mean concentration after vaccination when compared to Kisumu children.

In this context, the Advisory Committee observed that there appeared to be marked variation

across the study sites, and that some study sites seemed to be "high responders" and others

(particularly Kisumu) were "low responders". The Committee speculated that there could be

differences in the health status and weight of children between the sites, or that the vaccines

were not in their best condition in the ‘low responder’ sites (perhaps owing to cold chain

issues)18

.

As data on antigens other than measles and yellow fever is available from only two sites,

Manhica and Kisumu, the individual analyses for these studies is summarized.

In Manhica, the proportion of infants achieving protective titres post-vaccination was similar

in the SP and placebo groups for diphtheria, tetanus, polio type 1 & 3, and HepB (Hib

vaccine was not at the time included in the Mozambique vaccination schedule). The test of

non-inferiority (with a 10% threshold) was significant for each antigen, providing evidence

that SP treatment had no adverse impact on serological responses to EPI vaccines. There are

no know serological correlates of protection for pertussis. For all antigens, post-vaccination

GMCs and the reverse cumulative curves were similar in both the SP and placebo groups.

In Kisumu (Placebo, SP-ART, AQ-ART, LapDap):

• the post-vaccination GMC's for diphtheria, tetanus, Hib and pertussis toxin were similar

in the four treatment groups in both ITT & ATP analyses.

• For HepB, both in the ITT & ATP analyses, there was evidence to reject the null

hypothesis of equal GMC in all four groups.

• The hypothesis that the proportions unprotected in IPTi-treatment groups were at least

10% higher than in the placebo group was rejected, in both ITT & ATP analyses, for

diphtheria, tetanus, Hib, HepB and polio type 1.

17 Hib was assessed only in the Kisumu trial. Other antigens were also assessed in Bungoma, but these data were

excluded from pooled analyses as stated previously. 18 Differences were also observed in the proportions of children protected against measles within the placebo

groups in Kilimanjaro, Kisumu, Manhica and Navrongo. The proportion unprotected was highest in

Manhica and lowest in Navrongo.

16

• For polio type 3 the null hypothesis of inferiority (with respect to proportions

unprotected) of the LapDap and SP-ART groups compared to placebo for both ITT &

ATP analyses could not be rejected.

• The reverse cumulative distribution functions were similar for all antigens, except

HepB.

Given the difficulties of interpreting the HepB results an additional post-hoc analysis which

used 100 IU/L (instead of 10 IU/L)19 for inferiority was conducted.

The HepB analysis was compromised by the small sample size (n=222 which meant only

around 50 in each arm). There was no evidence of any problem with SP-ART, some

evidence that AQ-ART was better than placebo, and some very weak evidence that LapDap

might be worse than placebo, the proportions under 100 IU/L being quite high. However, no

definite conclusions could be drawn owing to the lack of power.

In Kisumu, a comparison of GMCs in the combined treatment group (SP-ART+AQ-

ART+LapDap) versus placebo group was conducted for diphtheria, pertussis FHA & toxin,

and tetanus, but not for hepatitis B. The GMCs in the combined treatment group were

similar to those for the placebo group. The reverse cumulative distribution functions were

also similar.

For proportions unprotected,, it was possible to pool the treatment groups for polio type 1 &

3 and diphtheria. The null hypothesis that the proportion unprotected is more than 10%

greater in the treatment group than in the placebo group was rejected for all antigens, in ITP

and ATP analyses.

Results – Yellow Fever (Navrongo)

Only one study site, Navrongo (Ghana) was able to provide data on serological responses to

yellow fever vaccination in infants randomized to receive SP or placebo. Unfortunately,

many of the samples selected had insufficient volumes for testing, and additionally there

was a miscommunication with the lab about the dilution, which further reduced the available

samples to only 136, when the protocol specified 250.

Owing to many complicating factors (small sample size; lack of clarity about the correlation

between protective titres and IU/ml concentration values; suspected interference with cross-

reactive antibodies for other flaviviruses) the analysis of the yellow fever data was limited to

differences between the groups post-vaccination..

Focusing only on the post-immunization samples, a comparison of the two groups was

undertaken on the entire cohort (not excluding any of the children with inconclusive

replicate samples, or detectable or protective antibody levels prior to immunization).

The proportions protected were similar in both groups. The formal test of non-inferiority

rejected the null hypothesis that the proportion unprotected in the treatment groups was

more than 10% greater than in the placebo group; the actual difference (SP minus placebo)

was 4.21%. Three methods adjusting and not for clustering produced similar results. The

19 100IU/L is the level at which long term immunity is conferred; 10 IU/L is the level for seroconversion.

17

geometric mean concentrations were found to be very similar in both groups. Finally, the

reverse cumulative distribution functions suggest that there is no reduction in antibody

concentrations in the SP group.

18

Conclusions of the WHO Advisory Committee

The Advisory Committee was established 6 years ago to review data generated by existing

studies. While it cannot be held responsible for the conduct of the field trials or laboratory

work, the Committee concludes the following:

1. Serological data from studies in Navrongo, Manhica, and Kilmanjaro provide strong

evidence that IPTi with SP, does not have an adverse impact on serological responses to

measles vaccine;

2. Though very limited, the available serological data from Navrongo provides evidence

that SP does not have a negative impact on antibodies following vaccination against

yellow fever;

3. Serological data from studies in Kisumu and Kilimanjaro provide strong evidence that

IPTi with SP-ART, AQ-ART, MQ, or LapDap do not have an adverse impact on

serological responses to measles vaccination;

4. Serological data from Manhica and Kisumu provide strong evidence that IPTi with

SP20

, SP-ART, AQ-ART, or LapDap do not have an adverse impact on serological

responses to DTP, polio, Hib, and HepB vaccines.

5. The pooled analyses provide further evidence that IPTi treatments do not impair

serological responses to EPI antigens.

20 Data from Bungoma, although weaker, also suggest that there is no negative interaction between SP

and EPI antigens.

Overall conclusion:

Studies have demonstrated that there is no adverse impact on the serological responses to

DTP, polio, Hib, HepB, and measles vaccines when the IPTi drugs SP, SP-ART, AQ-

ART, and LapDap are administered to infants at the time of routine vaccination.

Concomitant administration of IPTi-SP at the time of yellow fever vaccination, and IPTi-

MQ at the time of measles vaccination, have also been shown to have no negative effect

on the serological responses.

19

Annex 1: Report of the Technical Consultation on Intermittent

Preventive Treatment in Infants (IPTi), Technical Expert Group

(TEG) on Preventive Chemotherapy, April 23-24, 2009 Geneva..

Technical Expert Group meeting on Preventive chemotherapy

Report of the Technical Consultation on Intermittent Preventive Treatment in Infants (IPTi)

WHO HEADQUARTERS, GENEVA, 23–24 APRIL 2009

WHO HEADQUARTERS, GENEVA, 23–24 ApRil 2009

Technical Expert Group meeting on Preventive chemotherapy

Report of the technical consultation on Intermittent Preventive Treatment in Infants (IPTi)

Contents

1. Background ...............................................................................................................................................................................................1

2. Conclusions...............................................................................................................................................................................................3

3. Recommendations...........................................................................................................................................................................5

4. Other recommendations ........................................................................................................................................................7

5. References ...................................................................................................................................................................................................8

6. List of participants ......................................................................................................................................................................10

© World Health Organization 2009. All rights reserved.

The designations employed and the presentation of the material in this publication do not imply the expression of any opinion whatsoever on the part of the World Health Organization concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. Dotted lines on maps represent approximate border lines for which there may not yet be full agreement.

The mention of specific companies or of certain manufacturers’ products does not imply that they are endorsed or recommended by the World Health Organization in preference to others of a similar nature that are not mentioned. Errors and omissions excepted, the names of proprietary products are distinguished by initial capital letters.

All reasonable precautions have been taken by the World Health Organization to verify the information contained in this publication. However, the published material is being distributed without warranty of any kind, either expressed or implied. The responsibility for the interpretation and use of the material lies with the reader. In no event shall the World Health Organization be liable for damages arising from its use.

WHO Library Cataloguing-in-Publication Data

Technical expert group meeting on preventive chemotherapy : report of the technical consultation on intermittent preventive treatment in infants (IPTi) Geneva, 23-24 April 2009. 1.Malaria, Falciparum - prevention and control. 2.Malaria, Falciparum - drug therapy. 3.Infants. 4.Drug adminis-tration schedule. 5.Pyrimethamine - therapeutic use. 6.Sulfadoxine - therapeutic use. 7.Treatment outcomes. 8.Meta-analysis 9.Guidelines. I.World Health Organization.

ISBN 978 92 4 159858 2 (NLM classification: WC 765)

WHO Technical Expert Group on Preventive Chemotherapy 1

Intermittent preventive treatment in infancy (IPTi) is defined as:

the administration of a full course of an effective antimalarial treatment at specified

time points to infants at risk of malaria, regardless of whether or not they are parasitaemic, with the objective of reducing the infant malaria burden.

In October 2006 and October 2007, WHO convened meetings of the Technical Expert Group (TEG) on Intermittent Preventive Treatment in Infants to review the available evidence on the safety, efficacy and other relevant aspects of IPTi with sulfadoxine-pyrimethamine (SP-IPTi) delivered through the Expanded Programme for Immunization (EPI). At the time, six randomised, placebo-controlled clinical trials with SP-IPTi were being, or had been, conducted in areas of Africa, south of the Sahara with relatively high malaria endemicity (see Table). TEG 2006 concluded that SP-IPTi held promise as a potential malaria control intervention, noting that three of the studies were yet ongoing or unpublished.1 At the TEG 2007, at which time the six studies had been completed, the committee concluded that, though IPTi remains a potential intervention for malaria control, the use of SP-IPTi cannot be recommended as a strategy for general deployment based on the assessment of the risks and benefits, and advised a future review of further evidence when available.2

In the current expert review of the evidence on SP-IPTi, TEG 2009 reviewed the evidence available on SP-IPTi including additional data that were generated since the TEG-2007 meeting, with a view to making a definitive policy recommendation on this intervention for malaria control.

The new information reviewed was the following:

1. An in-depth analysis conducted by the IPTi Consortium3, of the severe skin reactions associated with SP-IPTi reported previously.4,5

2. Two additional randomized placebo controlled trials on the safety and efficacy of IPTi, which have been submitted for publication.6,7

3. The experience of implementation studies conducted by UNICEF in selected districts of six countries in Africa, south of the Sahara8 and another by the IPTi Consortium9–11 with respect to the feasibility of implementation, and its safety, monitored through active and passive observations on adverse reactions.

1. Background

2 WHO – Geneva, 23–24 April 2009

Table – Summary of site-specific information on the six published SP-IPTi trials considered for the pooled analysis*

Study site Study period Transmission pattern

Iron supplementation

# Infants studied SP/placebo**

Ifakara, UR Tanzaniai

1999–2000 perennial Yes 350/351

Navrongo, Ghanaii

2000–2004 Seasonal Yes 1183/1203

Manhica, Mozambiqueiii

2002–2004 perennial/seasonal peaks

None 748/755

Kumasi, Ghanaiv

2003–2005 perennial None 535/535

Tamale, Ghanav


None 600/600

Lambarene, Gabonvi


None 504/507

i ) Schellenberg D et al. (2001). Intermittent treatment for malaria and anaemia control at time of routine vaccinations in Tanzanian infants: a randomised, placebo-controlled trial. Lancet, 357:1471–1477.

ii) Chandramohan D et al. (2005). Cluster randomized trial of intermittent preventive treatment for malaria in infants in area of high, seasonal transmission in Ghana. Br Med J, 331:727–733.

iii) Macete E et al. (2006). Intermittent preventive treatment for malaria control administered at the time of routine vaccinations in Mozambican infants: a randomized, placebo controlled trial. J Inf Dis, 194:276–285.

iv) Kobbe R. et al. (2007). A randomized controlled trial of extended intermittent preventive antimalarial treatment in infants. Clin Infect Dis, 45:16–25.

v) Mockenhaupt FP et al. (2007). Intermittent Preventive Treatment in Infants as a Means of Malaria Control: a Randomized, Double-Blind, Placebo-Controlled Trial in Northern Ghana. Antimicrob Agents Chemother, 51: 3273–3281.

vi) Grobusch M. et al. (2007). Intermittent preventive treatment in infants against malaria in Gabon – a randomised, double-blind, placebo-controlled trial. J Inf Dis, 196: 1595–1602.

* The pooled analysis excludes the most recent study6 which was accepted for publication after the meeting, although its data were made available to the meeting.

** Who received at least the first dose of SP-IPTi


2. Conclusions

The TEG 2009 concluded that:

1. The previous safety concerns about SP-IPTi, specifically with respect to the reported severe skin reactions were mitigated by the evidence from the larger observational studies and retrospective in-depth examination by the Consortium of the severe skin reactions reported in previous studies.

2. The benefits of SP-IPTi in areas where SP remains effective against Plasmodium falciparum malaria parasites, were upheld as providing a 30% (95% CI: 19.8%–39.4%) overall protection against clinical malaria episodes and a variable reduction (overall 21.3%) (95% CI: 8.3%– 32.5%) in anaemia (< 8 g/dl) in a pooled analysis of data from 6 published studies (see Table).12 The reduction in all cause hospital admissions by 23% (95% CI: 10.0%–34.0%), was noted as a potential benefit. The admissions, however, were not all due to severe malaria, and this therefore cannot be equated to a similar reduction in the incidence of severe malaria. The pooled analysis excludes the most recent study6 which was accepted for publication after the meeting, although its data were made available to the meeting. The protective efficacy of SP-IPTi against clinical malaria episodes in this study was – 6.7% (95% CI: – 45.9–22.0).

3. Where effective, SP-IPTi offers a personal protection against clinical malaria for a period of approximately 35 days following the administration of each dose. There is no evidence for an individual cumulative protective effect beyond this period until the next dose. The mechanism of action appears to be predominantly chemoprophylaxis related to the half-life of the medicine and the susceptibility of the prevalent malaria parasites.

4. The protective efficacy of SP-IPTi is dependent upon the efficacy of SP, to which there is increasing parasite resistance in Africa and worldwide, but the threshold of parasite resistance to SP at which IPTi ceases to be effective is still not known. SP-IPTi was reported to provide benefit when the in vivo therapeutic failure rate of SP at day 14 was 31% (measured


in children with symptomatic malaria)13 and the population prevalence of Pfdhps + Pfdhfr quintuple mutants (molecular markers of parasite resistance to SP) was 50%14 but there was no benefit when the in vivo SP therapeutic failure rate was 82% at day 28, and the prevalence of the quintuple mutants was 90%.6

5. Uncertainties remain on the potential impact, or lack thereof, of SP-IPTi on the incidence of severe malaria or malaria mortality.

6. Uncertainties also remain on the impact of SP-IPTi at low levels of malaria transmission (either natural or resulting from effective control interventions).

7. A rebound effect by way of greater susceptibility to malaria following the termination of SP-IPTi was not evident in the pooled analysis. However, this warrants further observation in view of the fact that three of the studies reported an increase in either malaria infections associated high density parasitaemia15; anaemia (< 7.5 g/dl)4 ; or severe malaria and severe malarial anaemia (Hb < 5g/dl)5 during the post-intervention period in children who had received SP compared to the placebo group.

8. SP-IPTi was deemed a safe addition to EPI because there was no evidence of an adverse effect of SP-IPTi on infants’ serological response to EPI vaccines against DTP, Polio, Hepatitis B, Hib, yellow fever and measles.16

Limited implementation studies suggest that SP-IPTi incurs only marginally additional costs to EPI, and that it has a favorable effect on EPI coverage.

The panel comprised of 15 independent Experts. The Consultation was attended by observers from UNICEF, the Bill and Melinda Gates foundation, and the IPTi Consortium (Appendix 1, List of participants).


3. Recommendations

Considering that the benefits of SP-IPTi to infants are in providing a protection against clinical malaria from – 6.7% to 59.4%, and in view of increasing parasite resistance to SP, the TEG 2009 recommended that,

1. SP-IPTi delivered through EPI be considered for implementation as an additional malaria control intervention in countries in Africa, south of the Sahara under the following specific conditions,

a. In areas with moderate to high transmission (Annual Entomological Inoculation Rates [EIR] beyond 10).

b. When parasite resistance to SP in the area is not high. Precise cut-offs cannot be defined on the basis of available data. More information is needed on the relationship between the prevalence of molecular markers (mutations in Pfdhfr and Pfdhps) and the duration of malaria protection provided by SP-IPTi.

c. If its implementation does not detract from efforts to scale-up access to artemisinin-based combination therapies (ACT) for early treatment, and to insecticide-treated bednets (ITN) and indoor residual spraying (IRS) as preventive measures, all of which have significantly greater efficacy in malaria control.

2. Where SP-IPTi is used,

a. Continuous surveillance of parasite resistance to SP must accompany the implementation of SP-IPTi as a surrogate measure of its efficacy. Methodologies for monitoring the efficacy of SP-IPTi should be developed urgently to guide countries on when the intervention should no longer be deployed.


b. SP-IPTi should not be given to infants receiving a sulfa medication for treatment or prophylaxis against an infection, including co-trimoxazole (trimethoprim-sulfamethoxazole) which is widely used as a prophylactic against opportunistic infections in HIV-infected infants.

c. Surveillance for drug safety must be strengthened with effective pharmaco-vigilance systems to monitor serious adverse reactions to SP which may be exacerbated because SP-IPTi is likely to be implemented against a background of co-trimoxazole use for the treatment of acute respiratory infections in infants and for prevention of opportunistic infections in HIV-infected infants.


4. Other Considerations

The Technical Expert Group,

• Consideredtheseasonalityofmalariatransmission,andwhetherareasofseasonal malaria should be excluded for the implementation of SP-IPTi given that the optimal protective effect lasts for 35 days post treatment, but concluded that the evidence base did not support such an inference.

• RecognizedtheneedtodeveloptoolstomonitortheeffectivenessofSP-IPTi and validate a measure of parasite resistance to SP which can define a threshold at which SP-IPTi should not be implemented, and recommended that WHO GMP be financially supported to undertake this development as a priority.

• UrgedthedevelopmentofnewalternativemedicinesforIPTiasreplacementsfor SP, with properties conferring an optimum therapeutic profile for IPTi (single dose, excellent tolerability and long half-life) and reliably provide prophylaxis for a period of at least 4 weeks; new medicines for IPTi should preferably be different from those deployed for chemotherapeutic purposes, and should also be suitably formulated for the paediatric age group.

• Warned that the efficacy of SP is decreasing in many areas. Thoughdesirable, the development of a paediatric formulation for SP might take longer than its useful residual therapeutic life for IPTi and hence the simpler option of producing scored SP tablets should be considered.

• Requestedthatthefollowingquestionsbeaddressed:

– What are the optimum pharmacokinetic and pharmacodynamic properties required for medicines used for IPTi?

– What are the optimum ages for administering IPTi taking into account operational realities and burden of disease in relation to transmission intensity?

• Recommended that the assessment of impact on mortality should beconsidered among the endpoints for efficacy of the next candidate medicine for IPTi.


5. References

1. WHO (2006). Report of Technical Consultation on Intermittent Preventive Treatment for Malaria in Infancy (IPTi), Global Malaria Programme, World Health Organization, Geneva, 25-27 October, 2006.

2. WHO (2007). Report of the Technical Expert Group meeting on Intermittent preventive therapy in infancy (IPTi), Geneva, 8–10 October 2007. http://malaria.who.int/docs/IPTi/TEGConsultIPTiOct2007Report.pdf.

3. IPTi consortium (2009). Consortium Safety Panel (CSP) Report – April 2009.

4. Kobbe R. et al. (2007) A randomized controlled trial of extended intermittent preventive antimalarial treatment in infants. Clin Infect Dis, 45:16-25.

5. Mockenhaupt FP et al. (2007) Intermittent Preventive Treatment in Infants as a Means of Malaria Control: a Randomized, Double-Blind, Placebo-Controlled Trial in Northern Ghana. Antimicrob Agents Chemother, 51:3273-3281.

6. Gosling R et al. Protective efficacy and safety of three antimalarial regimens for intermittent preventive treatment for malaria in infants: a randomised, placebo-controlled trial. Lancet, in press.

7. Odhiambo F et al. Intermittent Preventive Treatment in Infants using long and short-acting drug combinations for the prevention of malaria and anaemia in rural western Kenya: a randomized, double-blind placebo controlled trials (unpublished).

8. UNICEF Operational Research on Intermittent Preventive Treatment of malaria in infants (IPTi): pharmacovigilance preliminary report, New York, March 2009 (unpublished).

9. Manzi F et al (2009) Intermittent preventive treatment for malaria and anemia control in Tanzanian infants; the development and implementation of a public health strategy. Trans R Soc Trop Med Hyg, 103:79-86.

10. Pool R et al. (2008) The acceptability of intermittent preventive treatment of malaria in infants (IPTi) delivered through the expanded programme of immunization in southern Tanzania. Malar J, 7:213.


11. Maokola W et al. The safety of sulphadoxine-pyrimethamine for intermittent preventive treatment of malaria in infants: evidence from large-scale operational research in southern Tanzania (unpublished).

12. Statistical Working Group of the IPTi Consortium: Pooled analysis of the IPTi trials with SP, 12 April 2009.

13. Schellenberg D et al. (2001) Intermittent treatment for malaria and anaemia control at time of routine vaccinations in Tanzanian infants: a randomised, placebo-controlled trial. Lancet, 357:1471-1477.

14. Mayor A et al. (2008) Molecular markers of resistance to sulfadoxine-pyrimethamine during intermittent preventive treatment for malaria in Mozambican infants. J Infect Dis, 197:1737-1742.

15. Chandramohan D et al. (2005) Cluster randomized trial of intermittent preventive treatment for malaria in infants in area of high, seasonal transmission in Ghana. Br Med J, 331:727-733.

16. WHO (2006). Interim report on IPTi with SP. WHO Advisory Committee on Serological responses to EPI vaccines in Infants receiving IPTi.


6. List of Participants

MEMBERS OF THE TECHNICAL EXPERT GROUP ON PREVENTIVE CHEMOTHERAPY

Dr Willis AKHWALEDirector, Communicable Diseases Division (former manager of National Malaria Control Programme)Ministry of Health KENYA.

Dr Karen BARNES*Associate ProfessorDivision of Clinical PharmacologyUniversity of Cape TownSOUTH AFRICA

Professor Fred BINKA (co-Chairperson)School of Public Health,University of GhanaGHANA

Professor Anders BJÖRKMANDivision of Infectious DiseasesKarolinska University HospitalSE-171 76 StockholmSWEDEN

Professor Ogobara DOUMBO*Director, Malaria Research and Training CentreBamakoMALI

Dr Issa MAKUMBI Head of Epidemiology and Surveillance,(former EPI Programme Manager) Ministry of HealthUGANDA


Dr Anne McCARTHY* Director, Tropical Medicine and International Health ClinicOttawa Hospital General CampusOttawa CANADA

Dr Theonest K. MUTABINGWA Associate Member, InternationalSeattle Biomedical Research InstituteMOMS ProjectMorogoroUR TANZANIA

Professor Olayemi OMOTADEDirector, Institute of Child HealthCollege of Medicine, University College HospitalIbadanNIGERIA

Professor Nick WHITE (co-Chairperson)Faculty of Tropical MedicineMahidol UniversityBangkokTHAILAND

Dr Abdoulaye DJIMDE (co-opted Member)*Malaria Research and Training CentreUniversity of BamakoMALI

Dr Feiko ter KUILE (co-opted Member)Liverpool School of Tropical MedicineLiverpoolUNITED KINGDOM

Dr Rick STEKETEE (co-opted Member)MACEPA PATHBâtiment Avant-CentreFerney-VoltaireFRANCE


Observers

Chair of Technical and Research Advisory Committee Professor Barry BLOOM

Members of the IPTI Consortium Dr Pedro ALONSO Dr John APONTE Dr Alasdair BRECKENRIDGE Dr Andrea EGAN Dr David SCHELLENBERG

Bill and Melinda Gates Foundation Dr David BRANDLING-BENNET Dr Erin SHUTES UNICEF Dr Alexandra DE SOUSA

WHO Secretariat

Global Malaria Programme Dr Sergio SPINACI - Associate Director, GMP Dr Kamini MENDIS Dr Peter OLUMESE Dr Pascal RINGWALD Dr Marian WARSAME

Expanded Programme on Immunization Dr Tracey GOODMAN

Special Programme for Research and Training in Tropical Diseases Dr Melba GOMES

WHO Regional Office for Africa Dr Georges A. KI-ZERBO

20

Annex 2: Membership of WHO Advisory Committee on serological

responses to Expanded Programme on Immunization vaccines in

infants receiving Intermittent Preventive Treatment for malaria

The Committee comprises two pediatricians with extensive experience in the laboratory

assessment of serological responses (CAS and DG), one expert in vaccine safety (OW), a

clinician with expertise in clinical trials of antimalarial drugs (PFo), and a biostatistician

with extensive experience in the statistical design of non-inferiority trials and analysis of

serological data (PFa).

Professor Claire-Anne Siegrist (Chairperson)

Head, WHO Collaborating Centre for Neonatal Vaccinology, Centre Médical Universitaire,

1 Rue Michel-Servet, 1211 Geneva, Switzerland

Professor Paddy Farrington

Department of Statistics, Open University, Milton Keynes, MK7 6AA, United Kingdom

Professor Peter Folb

Chief Specialist Scientist, Medical Research Council, Tygerberg 7505, Cape Town, South

Africa

Professor David Goldblatt

Professor of Vaccinology and Immunology, Immunobiology Unit, Institute of Child Health,

30 Guildford Street, London WC1N 1EH, United Kingdom

Dr Omala Wimalaratne

Head, Department of Rabies and Vaccines, Medical Research Institute, PO Box 527,

Colombo 8, Sri Lanka

Meeting: 19 May 2003

Meeting: 13 June 2003

Meeting: 11 June 2005

Teleconference: 30 September 2005

Teleconference: 8 November 2005

Teleconference: 5 April 2006


Teleconference: 6 October 2006

Teleconference: 8 March 2007

Teleconference: 14 August 2008

Teleconference: 14 November 2008

Teleconference: 11 February 2009

Teleconference: 11 March 2009


Teleconference: 7 July 2009

21

Annex 3: Final Pooled Analysis: Assessment of Serological

Responses to Expanded Programme on Immunization Vaccines in

Infants Receiving Intermittent Preventive Treatment (v.3 submitted

July 3, 2009)

Final pooled analysis V.3 Navrongo, Manhica, Kisumu, Kilimanjaro 03/07/2009

1

ASSESSMENT OF SEROLOGICAL RESPONSES TO EXPANDED PROGRAMME ON IMMUNISATION

VACCINES IN INFANTS RECEIVING INTERMITTENT PREVENTIVE TREATMENT

FINAL POOLED ANALYSIS V.2

<V.1 submitted February 26th 2009>

<V.2 submitted March 27th 2009>

<V.3 submitted July 3rd 2009>

Table of contents

Executive Summary

1. Background

2. Definitions

3. Statistical methods, samples, datasets and strategies of analysis

4. Proportions protected and distributions of antibody concentrations in the placebo groups

4.1 Measles

4.1.1 Analysis of post-vaccination measles antibody concentrations

4.1.2 Proportion of children with protective concentrations post-vaccination

4.1.2.1 Excluding those with protective measles concentrations in their pre-

vaccination sample

4.1.2.2 Excluding those with detectable measles concentrations in their pre-

vaccination sample

4.2 Diphtheria, Tetanus, Polio type 1 & 3, Pertussis toxin and FHA, and Hepatitis B responses

4.2.1 ITT analysis; post-vaccination concentrations & proportion protected

4.2.2 ATP analysis; post-vaccination concentrations & proportion protected

4.2.3 Children with protective concentrations to multiple antigens

5. Proportions protected and distributions of antibody concentrations in the SP groups

5.1 Measles




vaccination sample


vaccination sample

6. Proportions protected and distributions of antibody concentrations in the LapDap groups

6.1 Measles




vaccination sample


vaccination sample


2

7. Summary of within group comparisons across sites

8. Pooled SP Vs placebo comparison for measles

8.1 Investigation of effect modification by site

8.2 Measles




vaccination sample


vaccination sample

9. Pooled LapDap Vs placebo comparison for measles


9.2 Measles


10. Pooled combined treatment Vs placebo comparison for Kisumu site

10.1 Investigation of combined Vs individual treatment group comparison with placebo

10.2 Measles



10.3.1 ITT analysis; post-vaccination concentrations & proportion protected


11. Pooled combined treatment Vs placebo comparison for Kilimanjaro site


11.2 Measles




vaccination sample


vaccination sample

12. Appendices

12.1 Summary to the IPTi Consortium Trials

12.2 Post-hoc analysis I; pooled combined treatment group excluding LapDap Vs

placebo for Kisumu site

12.2.1 Investigation of combined Vs individual treatment group comparison with

placebo

12.2.2 Measles

12.2.2.1 Analysis of post-vaccination measles antibody concentrations

12.2.2.2 Proportion of children with protective concentrations post-

vaccination


3

12.2.2.2.1 Excluding those with protective measles concentrations

in their pre-vaccination sample

12.2.2.2.2 Excluding those with detectable measles concentrations


12.3 Post-hoc analysis II; pooled combined treatment group excluding LapDap Kisumu Vs

placebo for all sites

12.3.1 Investigation of combined Vs individual treatment group comparison with

placebo

12.3.2 Measles


12.3.2.2 Proportion of children with protective concentrations post-

vaccination

12.3.2.2.1 Excluding those with protective measles concentrations


12.3.2.2.2 Excluding those with detectable measles concentrations


Babis Sismanidis and Paul Milligan,

Tropical Epidemiology Group,

Infectious Disease Epidemiology Unit,

London School of Hygiene and Tropical Medicine


4

Executive summary

Five randomized placebo controlled trials across Africa were undertaken to investigate the

potential of malaria intermittent preventive treatment in infants (IPTi) having an adverse

impact on serological responses to Expanded Programme on Immunization (EPI) vaccines.

Serological response to measles vaccine was the primary outcome with diphtheria, tetanus,

polio type 1 & 3, pertussis toxin & FHA and hepatitis B being the secondary outcomes.

Analyses have been done separately for each trial. The current report presents analyses on

pooled data from the four trials conducted in Navrongo, Manhica, Kisumu and Kilimanjaro.

Data from the fifth trial, conducted in Bungoma, have been excluded due to concerns about

data quality. Infants were randomized into: i) placebo or SP in Navrongo and Manhica, ii)

placebo, SP-ART, AQ-ART and LapDap in Kisumu and iii) placebo, SP, MQ and LapDap in

Kilimanjaro. All four sites performed serological testing for measles. Only Manhica and Kisumu

performed serological testing on all other antigens.

Both Intention-to-Treat (ITT) and According-to-Protocol (ATP) populations have been

defined and analysed in this report. All children with pre and post measles vaccination

samples were included in the ITT analysis. From the ATP analysis, children with incomplete

drug dosing were excluded. Hence, only Navrongo children with all four drug doses taken and

Manhica, Kisumu and Kilimanjaro children with all three drug doses taken have been

considered for the ATP. For the measles analyses we excluded children with: i) detectable

and ii) protective pre-vaccination levels. For all other antigens all children with a post

vaccination sample were included in the ITT analysis, whereas children with incomplete drug

dosing were excluded from the ATP analysis. For all antigens we included analyses on two

outcomes: i) the continuous geometric mean concentration (GMC) post-vaccination and ii) the

binary protected/unprotected based on antigen levels above or below a pre-defined threshold

of protection for each antigen, where appropriate.

Firstly, we investigated within treatment group across trial comparisons.

i) The placebo group comparison across trials for all antigens presented in section 4. For

measles, post-vaccination GMC were highly significantly different across trials with

highest in the Navrongo trial (n=284), followed by Manhica (n=316) and finally Kisumu

(n=284) and Kilimanjaro (n=397) with the lowest and very similar antibody

concentrations. This finding remained consistent for the different sub-population

investigations (1. all children, 2. children without protective measles antibody

concentration level pre-vaccination and 3. children with undetectable concentration level

pre-vaccination). For the binary outcome of unprotected children post-vaccination the

formal test for comparison of percentages found no evidence to suggest a difference in

proportion across trials, for both ITT and ATP. For all other antigens placebo groups from


5

Manhica and Kisumu were available for analysis. Kisumu had a significantly higher

percentage of unprotected children for polio types 1 & 3 and diphtheria when compared

to Manhica. For tetanus and hepatitis B there was no evidence for a difference in the

respective percentages. These results were the same for ITT, ATP, excluding children

with detectable, excluding children with protective pre-vaccination concentration levels.

For diphtheria, pertussis toxin and FHA, tetanus and hepatitis B Manhica children had on

average a higher geometric mean concentration after vaccination when compared to

Kisumu children.

ii) The SP group comparison across Navrongo (n=336), Manhica (n=308) and Kilimanjaro

(n=374) for measles presented in section 5. Post measles vaccination geometric mean

concentration values were highest in the SP group from Navrongo site. This finding

remained consistent throughout the different sub-population investigations. Manhica also

consistently remained the second highest site followed by Kilimanjaro. Evidence found for

these differences was very strong as evidenced by ratios comparing GMC across trials

using Navrongo as reference. Whereas, no evidence was found to support differences in

percentages unprotected children across trials, for ITT, ATP, excluding children with

detectable, excluding children with protective pre-vaccination concentration levels.

iii) The LapDap group comparison across Kisumu (n=260) and Kilimanjaro (n=387) for

measles presented in section 6. Weak evidence was found to support post-measles

vaccination geometric mean concentration values were highest in the LapDap group from

Kisumu site when compared to Kilimanjaro. This finding remained consistent throughout

the different sub-population investigations. Strong evidence was found to support a

higher percentage of unprotected children in Kilimanjaro, compared to Kisumu for ITT,

ATP, excluding children with detectable, excluding children with protective pre-

vaccination concentration levels.

Subsequently, we investigated between treatment groups across trial comparisons. Data from

different trials were pooled only after establishing, by means of appropriate interaction tests,

that treatment effect was not modified in each trial. If there was evidence of effect

modification, pooling was not done and trial-specific treatment effects were reported.

i) The SP versus placebo comparison for Navrongo, Manhica and Kilimanjaro for measles

presented in section 8. No evidence of effect modification was found and hence data

were pooled across sites, resulting in 997 children in placebo and 1,018 in SP group. No

evidence was found to support a difference in the GMC between SP and placebo, for any

of the sub-population investigations. The formal test of non-inferiority of the null

hypothesis that the difference in percentages unprotected between the groups is 5% or

more, gives strong evidence suggesting SP is not inferior to placebo for ITT, ATP,


6

excluding children with detectable, excluding children with protective pre-vaccination

concentration levels.

ii) The LapDap versus placebo comparison for Kisumu and Kilimanjaro for measles

presented in section 9. No evidence of effect modification was found for the GMC

outcome and hence data were pooled across trials resulting in 681 children in placebo

and 647 in LapDap group. After pooling data across trials no evidence was found to

support a difference in the GMC between LapDap and placebo. However, for the binary

outcome of unprotected children evidence for effect modification across trials was found

and hence data were not pooled. The odds of being unprotected when in the LapDap

group were 1.26 (95% CI 0.69-2.31) times the odds of the placebo group for Kilimanjaro

and 0.32 (95% CI 0.10-1.01) for Kisumu, when excluding children with detectable pre-

vaccination concentration levels. When excluding children with protective pre-vaccination

concentration levels, the respective odds ratios were 1.46 (95% CI 0.84-2.55) for

Kilimanjaro and 0.29 (95% CI 0.09-0.88) for Kisumu.

iii) A post-hoc analysis of combining all treatment groups (excluding LapDap Kisumu) versus

placebo for Navrongo, Manhica, Kisumu and Kilimanjaro presented in appendix 12.3. No

evidence of heterogeneity by trial was found, therefore, data across the four trials were

pooled to study the overall combined treatment effect, resulting in 1,281 children in

placebo and 2,363 in the combined treatment group. No evidence was found to support a

difference in the measles GMC between the single combined treatment group and

placebo for any of the sub-population investigations. The formal test of non-inferiority, of

the null hypothesis that the difference in proportion unprotected between the

intervention groups is 5% or more, gives strong evidence suggesting combined group is

not inferior to placebo for both ITT, ATP, excluding children with detectable, excluding

children with protective pre-vaccination concentration levels.

Finally, we investigated combined treatment versus placebo group comparisons for individual

sites. Data from different treatment groups were combined only after establishing, by means

of appropriate interaction tests, that individual treatment effects were not different. If there

was evidence of effect modification, pooling was not done and individual treatment-specific

effects were reported.

i) (SP-ART + AQ-ART + LapDap) versus placebo in Kisumu for all antigens presented in

section 10. For measles, evidence was found against combining treatment groups for the

outcome of unprotected children and will not be presenting pooled estimates. Using

placebo as the reference group odds ratios for the comparison with SP-ART, AQ-ART and

LapDap were respectively: 1.21 (95% CI 0.57-2.56), 1.13 (95% CI 0.53-2.43), 0.32 (95%

CI 0.10-1.01) when excluding children with detectable pre-vaccination concentration.

When excluding children with protective pre-vaccination concentration respective odds


7

ratios were very similar. However, for the GMC outcome evidence supports the

combination of the three treatment groups into one and its comparison to placebo

resulting in 284 children in placebo and 838 in combined treatment group. No evidence

was found to support a difference in the measles GMC between the combined treatment

group and placebo for any sub-population investigations. For other antigens, evidence

was found supporting the pooled combined treatment group use for diphtheria, pertussis

FHA & toxin and tetanus, but not for hepatitis B, for the GMC outcome. Evidence also

supported the use of the single combined group for polio type 1 & 3 and diphtheria for

the binary outcome of unprotected children. There was no evidence found to support the

combined group as inferior by 10% or more compared to placebo. This result was

consistent across antigens and for both the ITT and ATP. For diphtheria, pertussis toxin

and FHA and tetanus children in the combined treatment group had on average similar

geometric mean concentration after vaccination when compared to placebo children.

ii) (SP + MQ + LapDap) versus placebo in Kilimanjaro for measles presented in section 11.

We found evidence supporting pooling treatment groups for both GMC and binary

outcome of unprotected children, resulting in 397 children in placebo and 1,141 in the

single combined treatment group. No evidence was found to support a difference in the

GMC between the combined treatment group and placebo. The formal test of non-

inferiority, of the null hypothesis that the difference in proportion unprotected between

the intervention groups is 5% or more, gives strong evidence suggesting combined group

is not inferior to placebo for both ITT, ATP, excluding children with detectable, excluding

children with protective pre-vaccination concentration levels.

iii) A post-hoc analysis of (SP-ART + AQ-ART) versus placebo in Kisumu for measles

presented in appendix 12.2. For both the binary outcome of unprotected children and the

GMC outcome evidence supported the combination of the two treatment groups into one

and its comparison to placebo, resulting in 284 children in placebo and 578 in the single

combined treatment group. No evidence was found to support a difference in the measles

GMC between the single combined treatment group and placebo for any of the sub-

population investigations. The formal test of non-inferiority, of the null hypothesis that

the difference in proportion unprotected between the intervention groups is 5% or more,

gives strong evidence suggesting combined group is not inferior to placebo for both ITT,

ATP, excluding children with detectable, excluding children with protective pre-

vaccination concentration levels.


8

1. Background

The aim of the study is to test the hypothesis that intermittent preventive treatment in infants

(IPTi) with sulfadoxine-pyrimethamine (SP) and selected other drug combinations does not

have an adverse impact on serological responses to Expanded Programme on Immunization

(EPI) vaccines, since it would be extremely damaging if the large scale introduction of IPTi

were followed by an increase in vaccine-preventable disease and death. The potential impact

of IPTi on recently introduced quadrivalent and pentavalent vaccines incorporating

Haemophillus Influenzae Type b and Hepatitis B respectively, also needs to be addressed. It

would also be valuable to document an increase in immune responsiveness to EPI antigens

that IPTi may induce through a reduction in malaria incidence. In the randomised trial of IPTi

by Schellenberg et al.1, seropositivity to measles and pertussis vaccines was 10% lower

among infants who received sulfadoxine-pyrimethamine (SP) compared to placebo, and

although analysis of further samples was more reassuring, there is a need for more extensive

data on the impact of IPTi on serological responses especially to measles vaccination.

Analyses have been done separately for each trial – Navrongo, Manhica, Bungoma, Kisumu

and Kilimanjaro – and presented in a series of interim reports to the Advisory Committee.

This report presents the definitive analysis using data from four of the five studies. Bungoma

data have been excluded from this final analysis due to concerns about data quality.

The tables below summarize the intervention groups children were randomized into and the

serological information available from each trial.

TABLE 1 Randomized intervention groups by site for measles

Navrongo Manhica Kisumu Kilimanjaro Placebo X X X X SP X X X SP-ART X AQ-ART X MQ X LapDap X X

SP – sulfadoxine-pyrimethamine; ART – artesunate; AQ – amodiaquine; MQ – mefloquine; LapDap – chlorproguanil-dapsone

TABLE 2 Randomized intervention groups by site for other antigens*

Manhica Kisumu Placebo X X SP X SP-ART X AQ-ART X LapDap X

* Polio type 1 & 3, Diphtheria, Tetanus, Hepatitis-B, Pertussis FHA & Toxin

1 Schellenberg D, Menendez C, Kahigwa E, et al. Intermittent treatment for malaria and anaemia control at time of routine vaccinations in Tanzanian infants: a randomised, placebo-controlled trial. Lancet 2001;357(9267):1471-7


9

See Appendix 12.1 for a useful summary to the trials.

2. Definitions

Protective concentrations are defined2 in the table below.

TABLE 3 Protective concentrations levels by antigen Measles 120 IU/L Polio Type 1 & 3 1:8 PRN titre Diphtheria 0.1 IU/ml Tetanus 0.1 IU/ml Hepatitis B 10 IU/L

There is no defined protective level for pertussis toxin and FHA.

3. Statistical methods, samples, datasets and strategies of analyses

For the purposes of the present pooled analysis report we have combined the four datasets

from Navrongo, Manhica, Kisumu and Kilimanjaro. The Navrongo study randomized clusters

of children, rather than children individually, into treatment groups. For the individual

Navrongo analysis report clustering was taken into consideration in all relevant analyses.

Manhica, Kisumu and Kilimanjaro on the other hand were individually randomized trials. To

see if we can ignore clustering for the Navrongo data (in order to pool with data from

Manhica) we have run the primary analysis (comparison of proportions protected in the two

intervention groups) twice; first time taking clustering into consideration and second time

ignoring it (results from these analyses are not reported here). There is no clustering effect in

the Navrongo data therefore it is ignored for the purposes of this analysis.

Both Intention-to-Treat (ITT) and According-to-Protocol (ATP) populations have been defined

and analysed in this report. All children with pre and post measles vaccination samples were

included in the ITT analysis. From the ATP analysis, children with incomplete drug dosing

were excluded. Hence, only Navrongo children with all four drug doses taken and Manhica,

Kisumu and Kilimanjaro children with all three drug doses taken have been considered for the

ATP. For the measles analyses we excluded children with: a) detectable and b) protective pre

vaccination levels.

Clinical, serology and randomization codes from all four trials were received between April

2005 and July 2008. Extensive data checking and cleaning took place with the help of the

laboratories and trial investigators. A draft statistical report was submitted on 26 February

2009.

For all antigens we included analyses on two outcomes: a) the continuous geometric mean

concentration (GMC) post-vaccination and b) the binary protected/unprotected based on

antigen levels above or below a pre-defined threshold of protection for each antigen, where

appropriate.

2 WHO Advisory Committee on EPI Serology in Relation to IPTi, Minutes, Meeting #2, Friday June 13, 2003, WHO Geneva


10

Firstly, we investigated within treatment group across site comparisons. This investigation

resulted in: i) the placebo group comparison across Navrongo, Manhica, Kisumu and

Kilimanjaro for all antigens, ii) the SP group comparison across Navrongo, Manhica and

Kilimanjaro for measles and iii) the LapDap group comparison across Kisumu and Kilimanjaro

for measles.

Subsequently, we investigated between treatment groups across site comparisons. The

appropriate analyses for this were: i) SP versus placebo comparison for Navrongo, Manhica

and Kilimanjaro for measles, ii) LapDap versus placebo comparison for Kisumu and

Kilimanjaro for measles and iii) a post-hoc analysis of combined treatment groups (excluding

LapDap Kisumu) versus placebo for Navrongo, Manhica, Kisumu and Kilimanjaro. Data from

different sites were pooled only after establishing, by means of appropriate interaction tests,

that treatment effect was not modified in each site. If there was evidence of effect

modification, pooling was not done and site-specific treatment effects were reported.

Finally, we investigated all-treatment-combined-into-one versus placebo group comparisons

for individual sites. The appropriate analyses for this were: i) (SP-ART + AQ-ART + LapDap)

versus placebo in Kisumu for all antigens, ii) (SP + MQ + LapDap) versus placebo in

Kilimanjaro for measles and iii) a post-hoc analysis of (SP + MQ) versus placebo in

Kilimanjaro for measles. Data from different treatment groups were combined only after

establishing, by means of appropriate interaction tests, that individual treatment effects were

not different. If there was evidence of effect modification, pooling was not done and

individual treatment-specific effects were reported.


11

4. Proportions protected and distributions of antibody concentrations in the placebo groups

4.1 Measles

In total there were 1,281 children assigned to the placebo groups with available serology

data in the four trials. We are restricting our analysis only on placebo groups and investigate

between site comparisons.


223 children had detectable concentrations in their pre-vaccination sample, 103 of these had

protective (≥ 120IU/L) concentration of measles antibodies in their pre-vaccination sample.

The next table summarises the geometric mean concentrations (GMC) in the four sites before

and after vaccination, and the median post-vaccination concentration.

TABLE 4 Antibody concentration response to the measles vaccination by treatment group GMC

pre-vaccination (95%CI)

GMC post-vaccination (95%CI) *

Median post-vaccination

Children with detectable concentrations pre-vaccination Navrongo (n=64) 241 (178, 327) 2260 (1660, 3075) 2141 Manhica (n=77) 222 (149, 331) 1832 (1299, 2584) 1984 Kisumu (n=36) 56 (37, 86) 755 (500, 1141) 945

Kilimanjaro (n=46) 76 (53, 108) 704 (494, 1003) 761 Children with undetectable concentrations pre-vaccination

Navrongo (n=220) 1439 (1213, 1707) 1424 Manhica (n=239) 962 (800, 1156) 896 Kisumu (n=248) 611 (529, 707) 633

Kilimanjaro (n=351) 621 (555, 696) 700 Ratio Manhica/Navrongo 0.67 (0.53, 0.84) Ratio Kisumu/Navrongo 0.42 (0.34, 0.53) P-value1 <0.0001 Ratio Kilimanjaro/Navrongo 0.43 (0.35, 0.53) Children with protective measles antibody level pre-vaccination

Navrongo (n=43) 417 (297, 586) 3010 (2083, 4350) 3050 Manhica (n=40) 714 (414, 1233) 2590 (1438, 4665) 3232

Kisumu (n=7) 536 (302, 952) 1130 (590, 2163) 1523 Kilimanjaro (n=13) 373 (194, 716) 1265 (604, 2651) 1588

Children without protective measles antibody level pre-vaccination Navrongo (n=241) 1422 (1210, 1671) 1422 Manhica (n=276) 998 (846, 1176) 975 Kisumu (n=277) 619 (538, 711) 637

Kilimanjaro (n=384) 616 (552, 689) 697 Ratio Manhica/Navrongo 0.70 (0.57, 0.87) Ratio Kisumu/Navrongo 0.43 (0.35, 0.54) P-value1 <0.0001 Ratio Kilimanjaro/Navrongo 0.43 (0.36, 0.53) All children

Navrongo (n=284) 1593 (1371, 1851) 1639 Manhica (n=316) 1126 (955, 1327) 1127 Kisumu (n=284) 628 (548, 720) 650

Kilimanjaro (n=397) 630 (566, 702) 701 Ratio Manhica/Navrongo 0.71 (0.58, 0.86) Ratio Kisumu/Navrongo 0.39 (0.32, 0.48) P-value1 <0.0001 Ratio Kilimanjaro/Navrongo 0.40 (0.33, 0.48)

*26 children had non-detectable concentrations post-vaccination. These undetectable levels were assigned a value of 11IU/L, half of the minimum concentration detected in the pooled dataset, for purposes of the analysis in this table (this affects the GMC but not the median). 1 P-value is calculated from the likelihood ratio test comparing the regression model with site as the only factor to its nested null model. H0=all ratios equal to 1


12

Post measles vaccination geometric mean concentration values were highest in the placebo

group from Navrongo site. This finding remained consistent throughout the different sub-

population investigations. Manhica also consistently remained the second highest site. Finally,

Kisumu and Kilimanjaro produced very similar antibody measles concentrations.

FIGURE 1 Reverse cumulative distribution function for measles for all children

0.2

.4.6

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Navrongo ManhicaKisumu Kilimanjaro

(vertical line indicates assumed protective threshold)Reverse empirical cumulative distribution function


4.1.2.1 Excluding those with protective measles concentrations in their pre-vaccination sample

103 children had protective concentrations of measles antibody in their pre-vaccination

sample. These children have been excluded from this point on, leaving 1,178 individuals.

TABLE 5 ITT proportion of children protected from measles; excluding those protected at pre-vaccination Protected Unprotected Total Percent unprotected Navrongo 233 8 241 3.32% Manhica 261 15 276 5.43% Kisumu 262 15 277 5.42% Kilimanjaro 361 23 384 5.99%

H0: Percentages unprotected equal across sites, 23Χ =2.28, P-value=0.52


13

A further 31 children are excluded from the ATP analysis, leaving 1,147 individuals.

TABLE 6 ATP proportion of children protected from measles; excluding those protected at pre-vaccination Protected Unprotected Total Percent unprotected Navrongo 225 7 232 3.02% Manhica 250 15 265 5.66% Kisumu 259 14 273 5.13% Kilimanjaro 355 22 377 5.84%


No evidence has been found to support differences in the percentages of unprotected

children across sites for the ITT or the ATP analysis.

FIGURE 2 Reverse cumulative distribution function for measles for the ITT cohort excluding those protected at pre-vaccination

0.2

.4.6

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4.1.2.2 Excluding those with detectable measles concentrations in their pre-vaccination sample

223 children had detectable concentrations of measles antibody in their pre-vaccination


TABLE 7 ITT proportion of children protected from measles; excluding those detectable at pre-vaccination Protected Unprotected Total Percent unprotected Navrongo 212 8 220 3.64% Manhica 224 15 239 6.28% Kisumu 235 13 248 5.24% Kilimanjaro 331 20 351 5.70%




14

TABLE 8 ATP proportion of children protected from measles; excluding those detectable at pre-vaccination Protected Unprotected Total Percent unprotected Navrongo 204 7 211 3.32% Manhica 216 15 231 6.49% Kisumu 234 12 246 4.88% Kilimanjaro 326 20 346 5.78%




FIGURE 3 Reverse cumulative distribution function for measles for the ITT cohort excluding children with detectable antibody levels at pre-vaccination

0.2

.4.6

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15

4.2 Diphtheria, Tetanus, Polio type 1 & 3, Pertussis toxin and FHA, and Hepatitis B responses in placebo groups

For the purposes of this analysis data from Manhica and Kisumu are being used. Serology data for these antigens is available for a total of 634 for the ITT

and 567 for the ATP analysis. Complete data on all antigens was available for 150 children.

4.2.1 ITT analysis; post-vaccination antibody concentrations & proportion protected

TABLE 9 ITT analysis for Diphtheria, Tetanus, Polio type 1 & 3, Pertussis toxin and FHA, and Hepatitis B; post-vaccination concentrations & proportions unprotected Polio Type 1

(n=499) Polio Type 3 (n=499)

Diphtheria (n=590)

Pertussis FHA (n=551)

Pertussis Toxin (n=388)

Tetanus (n=426)

Hep-B (n=318)

Protective threshold 1 in 8 PRN 1 in 8 PRN 0.1IU/ml Not defined (US units)

Not defined (US units)

0.1 IU/ml 10 IU/L

Percent unprotected (below threshold)

Manhica 27/250 10.80% 45/250 18.00%

4/331 1.21%

3/247 1.21%

9/250 3.60%

Kisumu 49/249 19.68% 95/249 38.15% 10/259 3.86% 1/179 0.56%

0/68 0.00%

P-value£ P=0.006 P<0.0001 P=0.04 P=0.49 P=0.11 GMC (95%CI)

Manhica 1.66 (1.52,1.82) n=331

30.1 (26.9,33.7) n=316

184 (157,217) n=227

5.46 (4.64,6.42) n=247

1068 (820,1391) n=250

Kisumu 0.75 (0.66,0.85) n=259

14.7 (12.9,16.7) n=235

67 (50,89) n=161

2.97 (2.52,3.52) n=179

505 (332,767) n=68

Ratio Kisumu/Manhica α (95% CI) P-value*

0.45 (0.39,0.52) P<0.0001

0.49 (0.41,0.58) P<0.0001

0.36 (0.27,0.49) P<0.0001

0.54 (0.43,0.54) P<0.0001

0.47 (0.27,0.82) P<0.0001

£ P-value is based on a chi-square comparison of the percentages of unprotected children in Manhica and Navrongo; α All ratio values are estimated from regression models with intervention arm as

the only factor;* This is the Wald test P-value from the regression model with site as the only factor. 1: 10 =Η r , where 1r is the ratio of ln GMCs for Kisumu compared to Manhica.


16


TABLE 10 ATP analysis for Diphtheria, Tetanus, Polio type 1 & 3, Pertussis toxin and FHA, and Hepatitis B; post-vaccination concentrations & proportions unprotected Polio Type 1

(n=450) Polio Type 3 (n=450)

Diphtheria (n=528)


Pertussis Toxin (n=343)

Tetanus (n=385)

Hep-B (n=290)



0.1 IU/ml 10 IU/L


Manhica 26/228 11.40% 41/228 17.98%

2/298 0.67%

3/224 1.34%

7/226 3.10%

Kisumu 41/222 18.47% 79/222 35.59% 8/230 3.48%

0/161 0.00%

0/64 0.00%

P-value£ P=0.04 P<0.0001 P=0.02 P=0.14 P=0.15 GMC (95%CI)

Manhica 1.69 (1.54,1.85) n=298

29.1 (26.0,32.7) n=387

184 (155,219) n=203

5.43 (4.57,6.46) n=224

1101 (842,1440) n=226

Kisumu 0.76 (0.66,0.87) n=230

14.9 (13.0,17.0) n=210

64 (48,86) n=140

2.88 (2.44,3.41) n=161

495 (319,769) n=64

Ratio Kisumu/Manhica α (95% CI) P-value*

0.45 (0.38,0.53) P<0.0001

0.51 (0.43,0.61) P<0.0001

0.35 (0.25,0.48) P<0.0001

0.53 (0.41,0.68) P<0.0001

0.45 (0.26,0.78) P<0.0001

£ P-value is based on a chi-square comparison of the percentages of unprotected children in Manhica and Navrongo; α All ratio values are estimated from regression models with intervention arm as

the only factor; * This is the Wald test P-value from the regression model with site as the only factor. 1: 10 =Η r , where 1r is the ratio of ln GMCs for Kisumu compared to Manhica.


17

Kisumu had a significantly higher percentage of unprotected children for polio types 1 & 3

and diphtheria when compared to Manhica. For tetanus and hepatitis B there was no

evidence for a difference in the respective percentages. These results were the same for both

ITT and ATP. For diphtheria, pertussis toxin and FHA, tetanus and hepatitis B Manhica

children had on average a higher geometric mean concentration after vaccination when

compared to Kisumu children.

FIGURE 4 Reverse cumulative distribution function for diphtheria

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-1.5 -1 -.5 0 .5 1log(10) diphtheria antibody concentration IU/ml

Manhica Kisumu



18

FIGURE 5 Reverse cumulative distribution function for pertussis FHA

0.2

.4.6

.81

0 1 2 3log(10) pertussis FHA antibody concentration IU/ml

Manhica Kisumu


FIGURE 6 Reverse cumulative distribution function for pertussis toxin

0.2

.4.6

.81

-1 0 1 2 3log(10) pertussis toxin antibody concentration IU/ml

Manhica Kisumu



19

FIGURE 7 Reverse cumulative distribution function for tetanus

0.2

.4.6

.81

-2 -1 0 1 2log(10) tetanus antibody concentration IU/ml

Manhica Kisumu


FIGURE 8 Reverse cumulative distribution function for hepatitis B

.2.4

.6.8

1

0 1 2 3 4log(10) Hepatitis B antibody concentration IU/L

Manhica Kisumu

(all children are above assumed protective threshold)Reverse empirical cumulative distribution function


20

4.2.3 Children with protective concentrations to multiple antigens

In the ITT analysis, 217 children had results for diphtheria, tetanus, polio type 1, polio type 3

and hepatitis B. In Manhica, 73.3% (126/172) had protective level for all five vaccine types,

compared to 48.9% (22/45) in Kisumu, a difference of -24.4% (90% CI -37.8%, -10.9%).

There was strong evidence found to suggest the proportion of these children with protective

concentrations of antibodies to all five when compared to those protected in four or less was

not the same in the two sites (test of association 21Χ =9.8, P=0.002).

TABLE 11 Number with protective concentration to 4 or less & 5 antigens: N (%) 4or less 5 TOTAL Manhica 46 (67) 126 (85) 172 (79) Kisumu 23 (33) 22 (15) 45 (21) TOTAL 69 (100) 348(100) 217 (100)


21

5. Proportions protected and distributions of antibody concentrations in the SP groups

5.1 Measles

In total there were 1,018 children assigned to the SP groups in the three (Navrongo, Manhica

and Kilimanjaro) trials. We are restricting our analysis in this section to SP groups, and

investigate between site comparisons.




The next table summarises the geometric mean concentrations (GMC) in the three sites

before and after vaccination, and the median post-vaccination concentration.





Children with detectable concentrations pre-vaccination Navrongo (n=82) 249 (191, 323) 2435 (1953, 3036) 2245 Manhica (n=54) 200 (125, 321) 1564 (970, 2520) 1485

Kilimanjaro (n=46) 71 (54, 92) 519 (345, 782) 444 Children with undetectable concentrations pre-vaccination

Navrongo (n=254) 1549 (1305, 1839) 1724 Manhica (n=254) 1008 (848, 1199) 1158

Kilimanjaro (n=328) 686 (611, 769) 733 Ratio Manhica/Navrongo 0.65 (0.52, 0.81) P-value1 <0.0001 Ratio Kilimanjaro/Navrongo 0.44 (0.36, 0.54) Children with protective measles antibody level pre-vaccination

Navrongo (n=54) 425 (311, 580) 2578 (1961, 3389) 2317 Manhica (n=27) 631 (315, 1266) 3293 (1720, 6305) 2606

Kilimanjaro (n=11) 254 (165, 389) 1172 (500, 2746) 608 Children without protective measles antibody level pre-vaccination


Kilimanjaro (n=363) 651 (582, 729) 705 Ratio Manhica/Navrongo 0.61 (0.50, 0.75) P-value1 <0.0001 Ratio Kilimanjaro/Navrongo 0.41 (0.33, 0.50) All children


Kilimanjaro (n=374) 663 (592, 741) 704 Ratio Manhica/Navrongo 0.63 (0.52, 0.77) P-value1 <0.0001 Ratio Kilimanjaro/Navrongo 0.38 (0.32, 0.46)

*19 children had non-detectable concentrations post-vaccination. These undetectable levels were assigned a value of 11IU/L, half of the minimum concentration detected in the pooled dataset, for purposes of the analysis in this table (this affects the GMC but not the median). 1 P-value is calculated from the likelihood ratio test comparing the regression model with site as the only factor to its nested null model. H0=all ratios equal to 1

Post measles vaccination geometric mean concentration values were highest in the SP group

from Navrongo site. This finding remained consistent throughout the different sub-population

investigations. Manhica also consistently remained the second highest site followed by

Kilimanjaro.


22


0.2

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Navrongo ManhicaKilimanjaro





sample. These children have been excluded from this point on, leaving 926 individuals.

TABLE 13 ITT proportion of children protected from measles; excluding those protected at pre-vaccination Protected Unprotected Total Percent unprotected Navrongo 274 8 282 2.84% Manhica 261 20 281 7.12% Kilimanjaro 342 21 363 5.79%


A further 26 children are excluded from the ATP analysis, leaving 900 individuals.

TABLE 14 ATP proportion of children protected from measles; excluding those protected at pre-vaccination Protected Unprotected Total Percent

unprotected Navrongo 264 8 272 2.94% Manhica 253 20 273 7.33% Kilimanjaro 334 21 355 5.92%


No strong evidence has been found to support differences in the percentages of unprotected



23


0.2

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TABLE 15 ITT proportion of children protected from measles; excluding those detectable at pre-vaccination Protected Unprotected Total Percent unprotected Navrongo 246 8 254 3.15% Manhica 237 17 254 6.69% Kilimanjaro 311 17 328 5.18%



TABLE 16 ATP proportion of children protected from measles; excluding those detectable at pre-vaccination Protected Unprotected Total Percent unprotected Navrongo 236 8 244 3.28% Manhica 230 17 247 6.88% Kilimanjaro 303 17 320 5.31%





24


0.2

.4.6

.81





25

6. Proportions protected and distributions of antibody concentrations in the LapDap groups

6.1 Measles

In total there were 647 children assigned to the LapDap groups in the four trials. We are

restricting our analysis in this section only on LapDap groups and investigate between site

comparisons.




The next table summarises the geometric mean concentrations (GMC) in the two sites before

and after vaccination, and the median post-vaccination concentration.





Children with detectable concentrations pre-vaccination Kisumu (n=33) 111 (60,205) 761 (452, 1282) 806

Kilimanjaro (n=33) 88 (58,135) 479 (305, 753) 554 Children with undetectable concentrations pre-vaccination

Kisumu (n=227) 712 (630, 805) 702 Kilimanjaro (n=354) 608 (540, 686) 678

Ratio Kisumu/Kilimanjaro 0.85 (0.71, 1.02) P-value1 0.08 Children with protective measles antibody level pre-vaccination

Kisumu (n=13) 559 (200,1564) 1448 (431, 4866) 1768 Kilimanjaro (n=12) 314 (166, 596) 1090 (610, 1948) 1127

Children without protective measles antibody level pre-vaccination Kisumu (n=247) 692 (616, 777) 675

Kilimanjaro (n=375) 585 (520, 658) 666 Ratio Kisumu/Kilimanjaro 0.85 (0.71, 1.00) P-value1 0.06 All children

Kisumu (n=260) 718 (634, 813) 704 Kilimanjaro (n=387) 596 (531, 670) 667

Ratio Kisumu/Kilimanjaro 0.83 (0.70, 0.99) P-value1 0.04 *11 children had non-detectable concentrations post-vaccination. These undetectable levels were assigned a value of 11IU/L, half of the minimum concentration detected in the pooled dataset, for purposes of the analysis in this table (this affects the GMC but not the median). 1 P-value is calculated from the likelihood ratio test comparing the regression model with site as the only factor to its nested null model. H0=all ratios equal to 1

Post measles vaccination geometric mean concentration values were highest in the LapDap

group from Kisumu site when compared to Kilimanjaro. This finding remained consistent

throughout the different sub-population investigations with some evidence for statistical

significance.


26


0.2

.4.6

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1 2 3 4log(10) measles antibody concentration post-vaccination

Kisumu Kilimanjaro






TABLE 18 ITT proportion of children protected from measles; excluding those protected at pre-vaccination Protected Unprotected Total Percent unprotected Kisumu 243 4 247 1.62% Kilimanjaro 343 32 375 8.53%

H0: Percentages unprotected equal across sites, 21Χ =13.1, P-value<0.0001


TABLE 19 ATP proportion of children protected from measles; excluding those protected at pre-vaccination Protected Unprotected Total Percent unprotected Kisumu 240 4 244 1.64% Kilimanjaro 334 30 364 8.24%


Strong evidence has been found to support a statistically significantly higher percentage of

unprotected children in Kilimanjaro compared to Kisumu, for both the ITT and ATP analysis.


27


0.2

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Kisumu Kilimanjaro





TABLE 20 ITT proportion of children protected from measles; excluding those detectable at pre-vaccination Protected Unprotected Total Percent unprotected Kisumu 223 4 227 1.76% Kilimanjaro 329 25 354 7.06%



TABLE 21 ATP proportion of children protected from measles; excluding those detectable at pre-vaccination Protected Unprotected Total Percent unprotected Kisumu 220 4 224 1.79% Kilimanjaro 322 25 347 7.20%


Strong evidence has been found to support a statistically significantly higher percentage of

unprotected children in Kilimanjaro compared to Kisumu, for both the ITT and ATP analysis.


28


0.2

.4.6

.81


Kisumu Kilimanjaro



29

7. Summary of within group comparisons across sites

TABLE 22 Summary of measles results from comparisons for each treatment across sites where appropriate

GMC post-vaccination ratios $ Percentage Unprotected £

MEASLES Excluding detectable

pre-vaccination

Excluding protected

pre-vaccination

Excluding detectable

pre-vaccination

Excluding protected

pre-vaccination Placebo

Navrongo Manhica Kisumu

Kilimanjaro

1

0.67 0.42 0.43

1

0.70 0.43 0.43

No difference across sites


SP Navrongo Manhica

Kilimanjaro

1

0.65 0.44

1

0.61 0.41


No difference across sites (P=0.07)

LapDap Kisumu

Kilimanjaro



1.76% 7.06%

1.62% 8.53%

$ Geometric mean concentrations, post measles vaccination, are compared across sites. Comparisons are done with ratio GMC values drawn from regression models with site as the only factor; £ Percentages of unprotected (<120 IU/L) children post measles vaccination are compared across sites; ITT population Percentages of unprotected children post measles vaccination were not found to be different

across sites for the placebo or the SP within group comparisons. In the LapDap groups

however, Kisumu had a significantly lower percentage of unprotected children when

compared to the Kilimanjaro group.

Geometric mean concentration ratio comparisons found strong evidence of differences across

sites for both the placebo and SP groups. We also found weak evidence of a difference in

GMC between Kisumu and Kilimanjaro for the LapDap comparison.


30

8. Pooled SP Vs Placebo comparison for measles

In this section of the report we will investigate the treatment effect of SP compared to

placebo using data from three sites; Navrongo, Manhica and Kilimanjaro. Before we pool data

from these three sites we will investigate whether the effect of SP Vs placebo is modified by

site. If effect modification is found pooling of the data is not appropriate and will not be done.


TABLE 23 SP Vs Placebo group comparison for measles by site and investigation of effect modification

GMC post-vaccination ratios $ OR Unprotected £


pre-vaccination (n=1,646)

Excluding protected




Excluding protected


Treatment Placebo

SP

1

1.08 (0.95-1.22)

1

1.05 (0.94-1.18)

1

0.95 (0.62-1.48)

1

1.06 (0.70-1.61) Site

Navrongo Manhica

Kilimanjaro

1

0.66 (0.56-0.77) 0.44 (0.38-0.51)

1

0.65 (0.56-0.76) 0.42 (0.36-0.48)

1

1.99 (1.07-3.67) 1.65 (0.90-3.00)

1

2.13 (1.16-3.90) 1.99 (1.11-3.57)

Interaction Treatment X Site P=0.94* P=0.66* P=0.92* P=0.70*

$ Geometric mean concentrations ratios of post measles vaccination are compared. Comparisons are done with ratio GMC values drawn from regression models with site and treatment group as the only factors £ Odds ratios of unprotected (<120 IU/L) children post measles vaccination are compared with site and treatment group as the only factors; ITT population * Likelihood ratio test comparing the model with to the model without the interaction terms between site & treatment

We have found no evidence for effect modification. Therefore, we will pool data across the

three sites to study the overall SP treatment effect.

8.2 Measles

In total 2,015 children are included in this analysis; 620 in Navrongo, 624 in Manhica, and

771 in Kilimanjaro. Measles vaccination is given at 9 months of age in all three sites. Children

were bled at 9 months of age before measles vaccination was administered to establish

baseline measles serology levels. Vaccine responses were measured by a subsequent blood

sample drawn at 10 months (Kilimanjaro) and 12 months of age (Manhica and Navrongo).

Measles serology data with matched pre and post vaccination measurements was available

for 2,015 children. Randomisation resulted in 997 in Placebo and 1,018 in SP groups. All

2,015 children were included in the ITT analyses. From the ATP analyses children were

excluded for not having received all drug doses.

TABLE 24 Numbers of children by study and treatment group for measles

Placebo SP TOTAL Navrongo 284 336 620 Manhica 316 308 624 Kilimanjaro 397 374 771 TOTAL 997 1,018 2,015


31


Characteristics of the 2,015 children, sampled at 9 months, included in the ITT analysis are as

follows:

TABLE 25 Baseline characteristics of children included in the ITT analysis Placebo

N=997 SP

N=1,018 Age in months at vaccination (mean, range) 9 (8, 12) 9 (8, 12)

%male : %female 50%:50% 51%:49%



The next table summarises the geometric mean concentrations (GMC) in the two treatment

groups before and after vaccination, and the median post-vaccination concentration.





Children with detectable concentrations pre-vaccination Placebo (n=187) 175 (140,219) 1556 (1268, 1909) 1522

SP (n=182) 170 (138,208) 1445 (1162, 1796) 1487 Children with undetectable concentrations pre-vaccination

Placebo (n=810) 888 (812, 971) 910 SP (n=836) 988 (903, 1080) 1048

Ratio SP/Placebo 1.08 (0.95, 1.22) P-value1 0.22 Children with protective measles antibody level pre-vaccination

Placebo (n=96) 514 (387, 683) 2514 (1850, 3417) 2354 SP (n=92) 449 (341, 591) 2521 (1936, 3282) 2294

Children without protective measles antibody level pre-vaccination Placebo (n=901) 893 (821, 971) 919

SP (n=926) 970 (890, 1057) 1026 Ratio SP/Placebo 1.05 (0.94, 1.18) P-value1 0.38 All children

Placebo (n=997) 987 (908, 1072) 1001 SP (n=1,018) 1057 (973, 1149) 1091

Ratio SP/Placebo 1.03 (0.92, 1.16) P-value1 0.55 *38 children had non-detectable concentrations post-vaccination. These undetectable levels were assigned a value of 11IU/L, half of the minimum concentration detected in the pooled dataset, for purposes of the analysis in this table (this affects the GMC but not the median). 1 P-value is calculated from the likelihood ratio test comparing the regression model with treatment group and site as the only factors to the model with only site. H0= ratio equal to 1

No evidence has been found to support a difference in the GMC between SP and placebo

groups.


32


0.2

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Placebo SP






TABLE 27 ITT proportion of children protected from measles; excluding those protected at pre-vaccination Protected Unprotected Total Percent unprotected Placebo 855 46 901 5.11% SP 877 49 926 5.29% Null hypothesis difference SP-Placebo of 5% Actual difference 0.18%, P<0.0001, z=-4.33 90%CI (-1.52, 1.89) 95%CI (-1.85, 2.22) 99%CI (-2.49, 2.86)


TABLE 28 ATP proportion of children protected from measles; excluding those protected at pre-vaccination Protected Unprotected Total Percent unprotected Placebo 830 44 874 5.03% SP 851 49 900 5.44% Null hypothesis difference SP-Placebo of 5% Actual difference 0.41%, P<0.0001, z=-4.07 90%CI (-1.33, 2.15) 95%CI (-1.66, 2.48) 99%CI (-2.31, 3.13)


33

The formal test of non-inferiority3, of the null hypothesis that the difference in proportion

unprotected between the intervention groups is 5% or more, gives strong evidence

suggesting SP is not inferior to placebo for both ITT and ATP.

FIGURE 16

Reverse cumulative distribution function for measles for the ITT cohort excluding those protected at pre-vaccination

0.2

.4.6

.81


Placebo SP





TABLE 29 ITT proportion of children protected from measles; excluding those with detectable concentration at pre-vaccination Protected Unprotected Total Percent unprotected Placebo 767 43 810 5.31% SP 794 42 836 5.02% Null hypothesis difference SP-Placebo of 5% Actual difference -0.29%, P<0.0001, z=-4.50 90%CI (-2.08, 1.51) 95%CI (-2.42, 1.85) 99%CI (-3.10, 2.53)

3 The one-sided P-values were calculated by referring the statistic: d = (pB-pA-d0)/√v0

to the standard normal distribution, P=Prob(z<d). pA is the observed proportion unprotected in placebo and pB the proportion unprotected in SP-ART, and d0 is the difference under the null hypothesis (d0=0.05 for measles and 0.1 for the other antigens), and v0 is the estimated variance of pB-pA under the null hypothesis. (In terms of the proportions protected qA and qB, d = (qA-qB-d0)/√v0 ). 100(1-α)% confidence intervals for the risk difference were calculated as pB-pA±z1-α/2√v where v=pA(1-pA)/NA+pB(1-pB)/NB. In the tables, percentages (100pA% etc) are presented rather than proportions.


34


TABLE 30 ATP proportion of children protected from measles; excluding those with detectable concentration at pre-vaccination Protected Unprotected Total Percent unprotected Placebo 746 42 788 5.33% SP 769 42 811 5.18% Null hypothesis difference SP-Placebo of 5% Actual difference -0.15%, P<0.0001, z=-4.30 90%CI (-1.99, 1.68) 95%CI (-2.33, 2.04) 99%CI (-3.03, 2.72)

The formal test of non-inferiority, of the null hypothesis that the difference in proportion


suggesting SP is not inferior to placebo for both ITT and ATP.


0.2

.4.6

.81


Placebo SP



35

FIGURE 18

Forest plot of the SP versus Placebo comparison for measles across sites

-0.40%

0.83%

-0.47%

-0.15%

-6.00% -4.00% -2.00% 0.00% 2.00% 4.00% 6.00%SP-Placebo difference

Navrongo Manhica Kilimanjaro POOLED


36

9. Pooled LapDap Vs placebo comparison for measles

In this section of the report we will investigate the treatment effect of LapDap compared to

placebo using data from two sites; Kisumu and Kilimanjaro. Before we pool data from these

two sites we will investigate whether the effect of LapDap Vs placebo is modified by site. If

effect modification is found pooling of the data is not appropriate and will not be done.


TABLE 31 LapDap Vs Placebo group comparison for measles by site and investigation of effect modification




Excluding protected




Excluding protected


Treatment Placebo LapDap

1

1.05 (0.93-1.19)

1

1.02 (0.90-1.15)

Kisumu Placebo LapDap

1

0.32 (0.10-1.01)

1

0.29 (0.09-0.88) Site

Kisumu Kilimanjaro

1

0.93 (0.82-1.06)

1

0.92 (0.81-1.04)

Kilimanjaro Placebo LapDap

1

1.26 (0.69-2.31)

1

1.46 (0.84-2.55) Interaction

Treatment X Site P=0.18* P=0.19* P=0.03* P=0.006* $ Geometric mean concentrations ratios of post measles vaccination are compared. Comparisons are done with ratio GMC values drawn from regression models with site and treatment group as the only factors £ Odds ratios of unprotected (<120 IU/L) children post measles vaccination are compared with site, treatment group and their interaction as the only factors; ITT population * Likelihood ratio test comparing the model with to the model without the interaction terms of site & treatment group

We have not found evidence for effect modification for the GMC outcome. Therefore, we will

pool data across the two sites to study the overall LapDap treatment effect. However,

evidence of effect modification has been found for the binary outcome of unprotected

children. We will not pool data for this outcome, and report site specific LapDap effects,

found in previously submitted analyses for Kisumu and Kilimanjaro sites separately.

9.2 Measles

In total 1,328 children are included in this analysis; 544 in Kisumu, and 784 in Kilimanjaro.

Measles vaccination is given at 9 months of age in all three sites. Children were bled at 9

months before measles vaccination was administered to establish baseline measles serology

levels. Vaccine efficacy was measured by a subsequent blood sample drawn at 10 months.


for 1,328 children. Randomisation resulted in 681 in Placebo and 647 in LapDap groups.


37


Placebo LapDap TOTAL Kisumu 284 260 544 Kilimanjaro 397 387 784 TOTAL 681 647 1,328



follows:


N=681 LapDap N=647

Age in months at vaccination (mean, range) 9 (8, 18) 9 (8, 16)

%male : %female 49%:51% 51%:49%









Children with detectable concentrations pre-vaccination Placebo (n=82) 67 (51,87) 726 (558, 944) 870 LapDap (n=66) 99 (69,142) 604 (429, 849) 618

Children with undetectable concentrations pre-vaccination Placebo (n=599) 617 (564, 675) 673 LapDap (n=581) 647 (593, 706) 679

Ratio LapDap/Placebo 1.05 (0.93, 1.19) P-value1 0.44 Children with protective measles antibody level pre-vaccination

Placebo (n=20) 423 (272, 658) 1216 (744, 1989) 1556 LapDap (n=25) 424 (237, 760) 1263 (666, 2400) 1321

Children without protective measles antibody level pre-vaccination Placebo (n=661) 617 (566, 672) 674 LapDap (n=622) 625 (574, 681) 670

Ratio LapDap/Placebo 1.02 (0.90, 1.15) P-value1 0.81 All children

Placebo (n=681) 629 (578, 685) 683 LapDap (n=647) 642 (590, 700) 677

Ratio LapDap/Placebo 1.02 (0.91, 1.15) P-value1 0.72 *26 children had non-detectable concentrations post-vaccination. These undetectable levels were assigned a value of 11IU/L, half of the minimum concentration detected in the pooled dataset, for purposes of the analysis in this table (this affects the GMC but not the median). 1 P-value is calculated from the likelihood ratio test comparing the regression model with treatment group and site as the only factors to its nested model with only site. H0= ratio equal to 1


38

No evidence has been found to support a difference in the GMC between LapDap and placebo

groups.


0.2

.4.6

.81


Placebo Lapdap



0.2

.4.6

.81


Placebo Lapdap



39


0.2

.4.6

.81


Placebo Lapdap



40

10. Pooled combined treatment Vs placebo comparison for Kisumu site

In this section of the report we will investigate, and present where appropriate, pooling the

three treatment groups (SP-ART, AQ-ART and LapDap) into one combined and compare

against placebo.


TABLE 35 Combined treatment effect in Kisumu site; measles



pre-vaccination (n=986)

Excluding protected




Excluding protected


Treatment Placebo SP-ART AQ-ART LapDap

1

1.11 (0.94-1.30) Single combined treatment group

1


1

1.21 (0.57-2.56) 1.13 (0.53-2.43) 0.32 (0.10-1.01)

1

1.21 (0.60-2.45) 1.18 (0.58-2.39) 0.29 (0.09-0.88)

LRT * P=0.69 P=0.67 P=0.02 P=0.006 $ Geometric mean concentrations ratios of post measles vaccination are compared. Comparisons are done with ratio GMC values drawn from regression models with treatment group as the only factor £ Odds ratios of unprotected (<120 IU/L) children post measles vaccination are compared with treatment group as the only factor; ITT population * Likelihood ratio test between: i) the model comparing each treatment group to placebo and ii) the model comparing a single combined treatment group to placebo

We have found evidence against combining treatment groups for the outcome of unprotected

children and will not be presenting pooled estimates. However, for the GMC outcome

evidence supports the combination of the three treatment groups into one and its comparison

to placebo.


41

TABLE 36 Combined treatment effect in Kisumu site; other antigens

OTHER ANTIGENS GMC post-vaccination

ratios $ OR Unprotected £

Treatment Placebo SP-ART AQ-ART LapDap

1

0.91 (0.63-1.31) Single combined treatment group Po

lio t

ype

1

LRT* P=0.80 Treatment

Placebo SP-ART AQ-ART LapDap

1

1.03 (0.76-1.38) Single combined treatment group Po

lio t

ype

3

LRT* P=0.15 Treatment


1 1.04 (0.89-1.22) Single combined treatment group

1

1.26 (0.62-2.58) Single combined treatment group D

ipht

heria

LRT * P=0.87 P=0.86 Treatment


1 0.92 (0.79-1.07) Single combined treatment group Pe

rtus

sis

FHA

LRT * P=0.17 Treatment



Pert

ussi

s to

xin




There is only 1 unprotected child in the placebo group

Teta

nus



1

1.05 (0.55-2.00) 2.35 (1.27-4.38) 0.84 (0.45-1.56)

There are no unprotected children

Hep

atiti

s B

LRT * P=0.004 $ Geometric mean concentrations ratios of post measles vaccination are compared. Comparisons are done with ratio GMC values drawn from regression models with treatment group as the only factor £ Odds ratios of unprotected (<120 IU/L) children post measles vaccination are compared with treatment group as the only factor; ITT population * Likelihood ratio test between: i) the model comparing each treatment group to placebo and ii) the model comparing a single combined treatment group to placebo We have found evidence supporting the pooled combined treatment group use for diphtheria,

pertussis FHA & toxin and tetanus, but not for hepatitis B, for the GMC outcome. Data also

support the use of the single combined group for polio type 1 & 3 and diphtheria for the

binary outcome of unprotected children.


42

10.2 Measles


for 1,122 children. Randomization resulted in 284 children in placebo, 285 in SP-ART, 293 in

AQ-ART and 260 in LapDap treatment groups.










Children with detectable concentrations pre-vaccination Placebo (n=36) 56 (37,86) 755 (500,1141) 945

Combined (n=100) 69 (51,92) 609 (475, 782) 648 Children with undetectable concentrations pre-vaccination

Placebo (n=248) 611 (529, 707) 633 Combined (n=738) 677 (625, 733) 680

Ratio Combined/Placebo 1.11 (0.94, 1.30) P-value 1 0.22 Children with protective measles antibody level pre-vaccination

Placebo (n=7) 536 (302, 952) 1130 (590, 2163) 1523 Combined (n=28) 464 (264, 816) 1109 (597, 2059) 1189


Combined (n=810) 657 (609, 709) 665 Ratio Combined/Placebo 1.06 (0.91, 1.24) P-value 1 0.44 All children


Ratio Combined/Placebo 1.06 (0.91, 1.24) P-value 1 0.42 *19 children had non-detectable concentrations post-vaccination. These undetectable levels were assigned a value of 11IU/L, half of the minimum concentration detected in the pooled dataset, for purposes of the analysis in this table (this affects the GMC but not the median). 1 P-value is calculated from the likelihood ratio test comparing the regression model with treatment group as the only factor to its nested null model. H0= ratio equal to 1

No evidence has been found to support a difference in the measles GMC between the

combined treatment group when compared to placebo.


43


0.2

.4.6

.81


Placebo Combined



0.2

.4.6

.81


Placebo Combined



44


0.2

.4.6

.81


Placebo Combined



45


10.3.1 ITT analysis; post-vaccination antibody concentrations & proportion protected TABLE 38 ITT analysis for diphtheria, tetanus, polio type 1 & 3, pertussis toxin & FHA and hepatitis B; post-vaccination antibody concentrations & proportion unprotected Polio Type 1

(n=968) Polio Type 3 (n=968)

Diphtheria (n=1,006)


Pertussis toxin (n=623)

Tetanus (n=700)




Placebo 49/249 19.68%

95/249 38.15%

10/259 3.86%

Combined 131/719 18.22%

279/719 38.80%

36/747 4.82%

Difference Combined-Placebo -1.46% 0.65% 0.96% Null hypothesis difference Combined-Placebo

10% 10% 10%

Test of non-inferiority Z=-4.41, P<0.0001+

Z=-2.70, P=0.004+

Z=-6.62 P<0.001+

90%CI (-6.23, 3.31) (-5.23, 6.53) (-1.40, 3.31) 95%CI (-7.15, 4.23) (-6.36, 7.66) (-1.85, 3.76) 99%CI (-8.93, 6.02) (-8.56, 9.86) (-2.73, 4.64)

GMC (95%CI) Placebo 0.75

(0.66,0.85) n=259

14.7 (12.9,16.7) n=235

67 (50,89) n=161

2.97 (2.52,3.52) n=179

Combined 0.78 (0.72,0.85) n=747

13.5 (12.5,14.6) n=658

74 (63,86) n=462

3.20 (2.92,3.51) n=521

Ratio Combined/Placebo α (95% CI) P-value*

1.04 (0.89,1.22) P=0.59

0.92 (0.79,1.07) P=0.28

1.11 (0.81,1.50) P=0.52

1.08 (0.89,1.30) P=0.44

+ 1.0: 210 =−Η pp , where 21, pp are proportions unprotected (below threshold) in the Combined Vs Placebo groups respectively; α All ratio values are estimated from regression models

with treatment group as the only factor; * This is the Wald test P-value from the regression model with treatment group as the only factor. 1: 10 =Η r , where 1r is the ratio of ln GMCs for

combined treatment group compared to placebo.


46


TABLE 39 ATP analysis for diphtheria, tetanus, polio type 1 & 3, pertussis toxin & FHA and hepatitis B; post-vaccination antibody concentrations & proportion unprotected Polio Type 1

(n=880) Polio Type 3 (n=880)

Diphtheria (n=913)


Pertussis toxin (n=563)

Tetanus (n=636)




Placebo 41/222 18.47%

79/222 35.59%

8/230 3.48%

Combined 117/658 17.78%

254/658 38.60%

32/683 4.69%

Difference Combined-Placebo -0.69% 3.01% 1.21% Null hypothesis difference Combined-Placebo

10% 10% 10%

Test of non-inferiority Z=-3.98, P<0.0001+

Z=-1.92, P=0.03+

Z=-6.27 P<0.0001+

90%CI (-5.62, 4.25) (-3.12, 9.15) (-1.18, 3.60) 95%CI (-6.57, 5.19) (-4.30,10.33) (-1.64, 4.06) 99%CI (-8.42, 7.04) (-6.60,12.63) (-2.54, 4.95)

GMC (95%CI) Placebo 0.76

(0.66,0.87) n=230

14.9 (13.0,17.0) n=210

64 (48,86) n=140

2.88 (2.44,3.41) n=161

Combined 0.78 (0.72,0.85) n=683

13.5 (12.4,14.6) n=603

73 (62,86) n=423

3.16 (2.87,3.48) n=475

Ratio Combined/Placebo α (95% CI) P-value*

1.03 (0.87,1.22) P=0.73

0.91 (0.77,1.06) P=0.23

1.14 (0.83,1.58) P=0.42

1.10 (0.90,1.33) P=0.35

+ 1.0: 210 =−Η pp , where 21, pp are proportions unprotected (below threshold) in the Combined Vs Placebo groups respectively; α All ratio values are estimated from regression models

with treatment group as the only factor; * This is the Wald test P-value from the regression model with treatment group as the only factor. 1: 10 =Η r , where 1r is the ratio of ln GMCs for

combined treatment group compared to placebo


47

There was no evidence found to support the combined group as inferior by 10% or more

compared to placebo. This result was consistent across antigens and for both the ITT and

ATP. For diphtheria, pertussis toxin and FHA and tetanus children in the combined treatment

group had on average similar geometric mean concentration after vaccination when

compared to placebo children.

FIGURE 25 Reverse cumulative distribution function for diphtheria

0.2

.4.6

.81

-2 -1 0 1 2log(10) diphtheria antibody concentration IU/ml

Placebo Combined



48

FIGURE 26 Reverse cumulative distribution function for pertussis FHA

0.2

.4.6

.81

0 1 2 3log(10) pertussis filamentous agglutinin (FHA) concentration US units

Placebo Combined


FIGURE 27 Reverse cumulative distribution function for pertussis toxin

0.2

.4.6

.81

-1 0 1 2 3 4log(10) pertussis toxin concentration US units

Placebo Combined



49

FIGURE 28 Reverse cumulative distribution function for tetanus

0.2

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.81

-2 -1 0 1 2log(10) tetanus antibody concentration IU/ml

Placebo Combined



50

11. Pooled combined treatment Vs placebo comparison for Kilimanjaro site


three treatment groups (SP, MQ and LapDap) into one combined group and compare against

placebo.


TABLE 40 Combined treatment effect in Kilimanjaro site for measles




Excluding protected




Excluding protected


Treatment Placebo

SP MQ

LapDap

1


1


1


1


LRT* P=0.24 P=0.28 P=0.54 P=0.35 $ Geometric mean concentrations ratios of post measles vaccination are compared. Comparisons are done with ratio GMC values drawn from regression models with treatment group as the only factor £ Odds ratios of unprotected (<120 IU/L) children post measles vaccination are compared with treatment group as the only factor; ITT population * Likelihood ratio test between: i) the model comparing each treatment group to placebo and ii) the model comparing a single combined treatment group to placebo

We have found evidence supporting pooling treatment groups for both GMC and binary

outcome of unprotected children. Therefore, we will be combining the three treatment groups

into one and comparing to placebo.

11.2 Measles


for 1,538 children. Randomization resulted in 397 children in placebo, 374 in SP, 380 in MQ

and 387 in LapDap treatment groups. For the purposes of section 11 we will refer to

‘combined’ as the single pooled SP, MQ and LapDap group.







51








Ratio Combined/Placebo 1.01 (0.89, 1.16) P-value1 0.83 Children with protective measles antibody level pre-vaccination



Combined (n=1109) 604 (565, 645) 665 Ratio Combined/Placebo 0.98 (0.86, 1.12) P-value1 0.76 All children


Ratio Combined/Placebo 0.97 (0.85, 1.10) P-value1 0.60 *19 children had non-detectable concentrations post-vaccination. These undetectable levels were assigned a value of 11IU/L, half of the minimum concentration detected in the pooled dataset, for purposes of the analysis in this table (this affects the GMC but not the median) 1 P-value is calculated from the likelihood ratio test comparing the regression model with treatment group as the only factor to the null model. H0= ratio equal to 1

No evidence has been found to support a difference in the GMC between the single combined

treatment group when compared to placebo.


0.2

.4.6

.81


Placebo Combined



52





TABLE 42 ITT proportion of children protected from measles; excluding those protected at pre-vaccination Protected Unprotected Total Percent unprotected Placebo 361 23 384 5.99% Combined 1,030 79 1,109 7.12% Null hypothesis difference Combined-Placebo of 5% Actual difference 1.13%, P=0.001, z=-2.99 90%CI (-1.23, 3.50) 95%CI (-1.68, 3.94) 99%CI (-2.57, 4.83)


TABLE 43 ATP proportion of children protected from measles; excluding those protected at pre-vaccination Protected Unprotected Total Percent unprotected Placebo 355 22 377 5.84% Combined 972 73 1,045 6.99% Null hypothesis difference Combined-Placebo of 5% Actual difference 1.15%, P=0.002, z=-2.95 90%CI (-1.22, 3.52) 95%CI (-1.68, 3.98) 99%CI (-2.56, 4.86)



suggesting combined group is not inferior to placebo for both ITT and ATP.


53

FIGURE 30


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Placebo Combined





TABLE 44 ITT proportion of children protected from measles; excluding those with detectable concentration at pre-vaccination Protected Unprotected Total Percent unprotected Placebo 331 20 351 5.70% Combined 965 61 1,026 5.95% Null hypothesis difference Combined-Placebo of 5% Actual difference 0.25%, P=0.0001, z=-3.77 90%CI (-2.12, 2.62) 95%CI (-2.58, 3.07) 99%CI (-3.46, 3.96)


TABLE 45 ATP proportion of children protected from measles; excluding those with detectable concentration at pre-vaccination Protected Unprotected Total Percent unprotected Placebo 326 20 346 5.78% Combined 911 58 969 5.99% Null hypothesis difference Combined-Placebo of 5% Actual difference 0.21%, P=0.0001, z=-3.70 90%CI (-2.21, 2.62) 95%CI (-2.67, 3.08) 99%CI (-3.58, 3.99)


54


unprotected between the combined treatment group is 5% or more, gives strong evidence

suggesting non-inferiority compared to placebo for both ITT and ATP.


0.2

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.81


Placebo Combined



55

12. Appendices

12.1 Summary to the IPTi Consortium Trials

IPTi studies that include assessment of serological responses to EPI vaccines Study site

Study design

Drug(s) for IPTi

Age at IPTi drug dosing

Sample size

EPI immunisation schedule

Timing of blood samples

Serological information available from each study

Navrongo, Ghana

RCT

SP Placebo

10 weeks (DTP2) 14 weeks (DTP3) 9 months (measles) 12 months

500 SP 500 placebo

BCG: birth DTP, hepB, Hib: 6, 10, 14 weeks Polio: birth, 6, 10, 14 weeks Measles, yellow fever: 9 months

9 months 12 months

Measles, yellow fever

Bungoma, Kenya

RCT

SP Placebo

10 weeks (DTP2) 14 weeks (DTP3) 9 months (measles)

500 SP 500 placebo

BCG: birth DTP, hepB, Hib: 6, 10, 14 weeks Polio: birth, 6, 10, 14 weeks Measles: 9 months

6 weeks 18 weeks 9 months 10 months

DTP, polio, hepatitis B, Hib, measles

Manhica, Mozambique

RCT

SP Placebo


500 SP 500 placebo

BCG: birth DTP, hepB: 8, 12, 16 weeks Polio: birth, 8, 12, 16 weeks Measles: 9 months

20 weeks 9 months 12 months

DTP, polio, hepatitis B measles

Kisumu, Kenya

RCT SP/Art

AQ/Art LapDap Placebo


379 x 3 intervention 379 placebo

As for Bungoma

6 weeks 18 weeks 9 months 12 months

DTP, polio, hepatitis B, Hib, measles

Kilimanjaro, Tanzania

RCT SP

MQ LapDap Placebo


500 x 3 intervention 500 placebo

BCG: birth DTP, hepB: 4, 8, 12 weeks Polio: birth, 4, 8, 12 weeks Measles: 9 months

9 months 10 months

Measles

Legend: RCT: randomised controlled trial; SP: sulfadoxine-pyrimethamine; SP/Art: sulfadoxine-pyrimethamine plus artesunate; MQ: mefloquine; LapDap: chlorproguanil-dapsone; AQ/Art: amodiaquine plus artesunate; DTP: diphtheria, tetanus, pertussis; hepB: hepatitis B; Hib: Haemophilus influenzae type b


56

Serological assays Vaccine Pre or post-

vaccination sample

Timing of blood samples

Type of test Protective level

Measles

Pre

9 months Plaque reduction neutralisation (PRN) 1-2 dilutions

To check for presence of measles antibodies pre-vaccination

Post 10 months or 12 months

PRN 6 dilutions (GMT) 120 IU/l

Yellow fever Pre 9 months PRN 1-2 dilutions To check for presence of YF antibodies pre-vaccination

Post 10 months or 12 months


Diphtheria Pre At time of DTP1 Store in freezer*

Post One month post DTP3

Quantitative ELISA (GMT)

0.1 IU/ml

Tetanus Pre At time of DTP1 Store in freezer*



0.1 IU/ml

Pertussis (PT and FHA only)




Protective levels not defined

Polio (serotypes 1 and 3 only)




Haemophilus influenzae type b




0.15 µg/ml (1.0 µg/ml will be used as a secondary descriptive)

Hepatitis B Pre At time of DTP1 Store in freezer*



10 IU/l

* Pre-vaccination GMTs will only be obtained if the post-vaccination results are equivocal; PRN: Plaque reduction neutralisation; GMT: Geometric mean titre; PT: Pertussis toxin; FHA: Filamentous haemagglutinin


57

12.2 Post-hoc analysis I; pooled combined treatment group excluding LapDap Vs placebo

for Kisumu site


two treatment groups (SP-ART and AQ-ART) into one combined and compare against placebo

for Kisumu site. We are excluding LapDap group from all analyses in this section.

12.2.1 Investigation of combined Vs individual treatment group comparison with placebo

TABLE 46 Combined treatment effect in Kisumu site; for measles antigen




Excluding protected




Excluding protected


Treatment Placebo SP-ART AQ-ART

1

1.08 (0.91-1.29) Combined group

1


1


1


LRT * P=0.66 P=0.67 P=0.89 P=0.94 $ Geometric mean concentrations ratios of post measles vaccination are compared. Comparisons are done with ratio GMC values drawn from regression models with treatment group as the only factor £ Odds ratios of unprotected (<120 IU/L) children post measles vaccination are compared with treatment group as the only factor; ITT population * Likelihood ratio test between: i) the model comparing each treatment group to placebo and ii) the model comparing a single combined treatment group to placebo

For both the binary outcome of unprotected children and the GMC outcome evidence

supports the combination of the two treatment groups into one and its comparison to

placebo.

12.2.2 Measles


for 862 children. Randomization resulted in 284 children in placebo, 285 in SP-ART and 293 in

AQ-ART treatment groups.


58
















Combined (n=563) 642 (583, 707) 653 Ratio Combined/Placebo 1.04 (0.88, 1.23) P-value 1 0.67 All children


Ratio Combined/Placebo 1.03 (0.87, 1.22) P-value 1 0.72 *18 children had non-detectable concentrations post-vaccination. These undetectable levels were assigned a value of 11IU/L, half of the minimum concentration detected in the pooled dataset, for purposes of the analysis in this table (this affects the GMC but not the median). 1 P-value is calculated from the likelihood ratio test comparing the regression model with treatment group as the only factor to its nested null model. H0= ratio equal to 1

No evidence has been found to support a difference in the measles GMC between the single

combined treatment group and placebo.


59


0.2

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Placebo Combined


12.2.2.2 Proportion of children with protective concentrations post-vaccination

12.2.2.2.1 Excluding those with protective measles concentrations in their pre-vaccination sample



TABLE 48 ITT proportion of children protected from measles; excluding those protected at pre-vaccination Protected Unprotected Total Percent unprotected Placebo 262 15 277 5.42% Combined 527 36 563 6.39% Null hypothesis difference Combined-Placebo of 5% Actual difference 0.97%, P=0.006, z=-2.49 90%CI (-1.83, 3.79) 95%CI (-2.37, 4.32) 99%CI (-3.42, 5.37)


60


TABLE 49 ATP proportion of children protected from measles; excluding those protected at pre-vaccination Protected Unprotected Total Percent unprotected Placebo 259 14 273 5.13% Combined 523 35 558 6.27% Null hypothesis difference Combined-Placebo of 5% Actual difference 1.14%, P=0.008, z=-2.42 90%CI (-1.63, 3.91) 95%CI (-2.16, 4.44) 99%CI (-3.19, 5.48)




FIGURE 33


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Placebo Combined



61

12.2.2.2.2 Excluding those with detectable measles concentrations in their pre-vaccination sample



TABLE 50 ITT proportion of children protected from measles; excluding those with detectable concentration at pre-vaccination Protected Unprotected Total Percent unprotected Placebo 235 13 248 5.24% Combined 480 31 511 6.07% Null hypothesis difference Combined-Placebo of 5% Actual difference 0.83%, P=0.006, z=-2.50 90%CI (-2.08, 3.73) 95%CI (-2.64, 4.29) 99%CI (-3.72, 5.37)


TABLE 51 ATP proportion of children protected from measles; excluding those with detectable concentration at pre-vaccination Protected Unprotected Total Percent unprotected Placebo 234 12 246 4.88% Combined 476 30 506 5.93% Null hypothesis difference Combined-Placebo of 5% Actual difference 1.05%, P=0.008, z=-2.41 90%CI (-1.79, 3.89) 95%CI (-2.33, 4.44) 99%CI (-3.40, 5.50)





62


0.2

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Placebo Combined



63

12.3 Post-hoc analysis II; pooled combined treatment group excluding LapDap Kisumu Vs

placebo for all sites

In this section of the report we will investigate the treatment effect of the pooled combined

treatment group when compared to placebo using data from all four sites; Navrongo,

Manhica, Kisumu and Kilimanjaro. We have already established that pooling of the two

treatment groups, excluding LapDap, is appropriate for Kisumu site. We have also already

established that pooling of the three treatment groups is appropriate for Kilimanjaro site.

Before we further pool data from these four sites we will investigate whether the effect of

combined Vs placebo is modified by site. If heterogeneity is found pooling of the data is not

appropriate and will not be done.

12.3.1 Investigation of combined Vs individual treatment group comparison with placebo

TABLE 52 Combined Vs Placebo group comparison for measles by site and investigation of effect modification




Excluding protected




Excluding protected


Treatment Placebo

Combined

1

1.05 (0.96-1.15)

1

1.02 (0.93-1.11)

1

1.06 (0.76-1.48)

1

1.18 (0.87-1.62) Site

Navrongo Manhica Kisumu

Kilimanjaro

1

0.66 (0.57-0.77) 0.43 (0.37-0.49) 0.42 (0.37-047)

1

0.65 (0.56-0.75) 0.42 (0.37-0.48) 0.40 (0.35-0.45)

1

1.99 (1.08-3.68) 1.75 (0.97-3.14) 1.77 (1.02-3.07)

1

2.13 (1.17-3.91) 2.00 (1.13-3.56) 2.25 (1.31-3.86)

Interaction Treatment X Site P=0.95* P=0.71* P=0.97* P=0.91*

$ Geometric mean concentrations ratios of post measles vaccination are compared. Comparisons are done with ratio GMC values drawn from regression models with site and treatment group as the only factors £ Odds ratios of unprotected (<120 IU/L) children post measles vaccination are compared with site and treatment group as the only factors; ITT population * Likelihood ratio test comparing the model with to the model without the interaction terms between site & combined treatment We have found no evidence of heterogeneity by site. Therefore, we will pool data across the

four sites to study the overall combined treatment effect.

12.3.2 Measles

In total 3,644 children are included in this analysis; 620 in Navrongo, 624 in Manhica, 862 in

Kisumu and 1,538 in Kilimanjaro. Measles vaccination is given at 9 months of age in all four

sites. Children were bled at 9 months of age before measles vaccination was administered to

establish baseline measles serology levels. Vaccine responses were measured by a

subsequent blood sample drawn at 10 months (Kisumu, Kilimanjaro) and 12 months of age

(Manhica and Navrongo).


64


for 3,644 children. Randomisation resulted in 1,281 in Placebo and 2,363 in combined group.

All 3,644 children were included in the ITT analyses. From the ATP analyses children were

excluded for not having received all drug doses.


Placebo Combined TOTAL Navrongo 284 336 620 Manhica 316 308 624 Kisumu 284 578 862 Kilimanjaro 397 1,141 1,538 TOTAL 1,281 2,363 3,644

.



follows:


N=1,281 Combined N=2,363

Age in months at vaccination (mean, range) 9 (8, 18) 9 (8, 19)

%male : %female 50%:50% 52%:48%






65










Children without protective measles antibody level pre-vaccination Placebo (n=1,178) 819 (762, 881) 848

Combined (n=2,235) 737 (700, 776) 768 Ratio Combined/Placebo 1.02 (0.93, 1.11) P-value 1 0.67 All children

Placebo (n=1,281) 893 (830, 959) 899 Combined (n=2,363) 774 (735, 815) 795

Ratio Combined/Placebo 1.00 (0.92, 1.09) P-value 1 0.92 *74 children had non-detectable concentrations post-vaccination. These undetectable levels were assigned a value of 11IU/L, half of the minimum concentration detected in the pooled dataset, for purposes of the analysis in this table (this affects the GMC but not the median). 1 P-value is calculated from the likelihood ratio test comparing the regression model with treatment group and site as the only factors to the model with only site. H0= ratio equal to 1

No evidence has been found to support a difference in the measles GMC between the single

combined treatment group and placebo.


66


0.2

.4.6

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Placebo Combined


12.3.2.2 Proportion of children with protective concentrations post-vaccination

12.3.2.2.1 Excluding those with protective measles concentrations in their pre-vaccination sample



TABLE 56 ITT proportion of children protected from measles; excluding those protected at pre-vaccination Protected Unprotected Total Percent unprotected Placebo 1,117 61 1,178 5.18% Combined 2,092 143 2,235 6.40% Null hypothesis difference Combined-Placebo of 5% Actual difference 1.22%, P<0.0001, z=-4.76 90%CI (-0.14, 2.58) 95%CI (-0.40, 2.84) 99%CI (-0.91, 3.35)


67


TABLE 57 ATP proportion of children protected from measles; excluding those protected at pre-vaccination Protected Unprotected Total Percent unprotected Placebo 1,089 58 1,147 5.06% Combined 2,012 136 2,148 6.33% Null hypothesis difference Combined-Placebo of 5% Actual difference 1.27%, P<0.0001, z=-4.64 90%CI (-0.10, 2.65) 95%CI (-0.36, 2.91) 99%CI (-0.87, 3.42)




FIGURE 36


0.2

.4.6

.81


Placebo Combined



68

12.3.2.2.2 Excluding those with detectable measles concentrations in their pre-vaccination sample



TABLE 58 ITT proportion of children protected from measles; excluding those with detectable concentration at pre-vaccination Protected Unprotected Total Percent unprotected Placebo 1,002 56 1,058 5.29% Combined 1,928 117 2,045 5.72% Null hypothesis difference Combined-Placebo of 5% Actual difference 0.43%, P<0.0001, z=-5.59 90%CI (-0.98, 1.84) 95%CI (-1.25, 2.11) 99%CI (-1.78, 2.64)


TABLE 59 ATP proportion of children protected from measles; excluding those with detectable concentration at pre-vaccination Protected Unprotected Total Percent unprotected Placebo 980 54 1,034 5.22% Combined 1,853 113 1,966 5.75% Null hypothesis difference Combined-Placebo of 5% Actual difference 0.53%, P<0.0001, z=-5.39 90%CI (-0.90, 1.95) 95%CI (-1.18, 2.22) 99%CI (-1.71, 2.76)





69


0.2

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Placebo Combined


22

Annex 4: Summaries of Individual Study Results

Navrongo, Ghana

Introduction

This was a cluster randomised controlled comparison of IPTi-SP or placebo given at DTP2,

DTP3 and measles vaccination, with an extra dose given at 12 months of age not linked with

vaccination. All infants received one month of iron supplementation at the time of drug

administration. There were 48 clusters (comprised of 100 households) in each arm and a

total of 2,485 children. Unlike the other IPTi studies, this study was conducted in a region in

which yellow fever vaccine was administered concurrently with measles at 9 months of age.

It should be noted that the Navrongo study was nearing completion at the time that the

protocol for the EPI serology studies was being designed. Since the study provided a unique

opportunity to obtain information on serological responses to yellow fever vaccination, a

retrospective decision was made to measure serological responses to measles and yellow

fever on a selection of blood samples taken at 9 and 12 months. Paired pre- and post-

vaccination blood samples on infants documented as having received concurrent measles

and yellow fever vaccination at 9 months were therefore selected from each cluster for

yellow fever serology. Additional paired sera for measles serology were selected from

children that had received measles vaccine alone.

Results

For detailed results see Interim Report Navrongo (May 17, 2006) and Final Yellow Fever

Serology Report Navrongo (Final Draft November 20, 2006).

Measles

Of 2,485 infants enrolled, blood samples for measles serology were obtained from 336

infants who received SP (from 48 clusters) and from 284 infants who received placebo

(from 47 clusters). Post-vaccination geometric mean antibody titres (GMT) in 146 infants

that had detectable levels of measles antibody prior to vaccination were much higher (see

statistical report) than the post-vaccination GMTs in infants with undetectable levels of

measles antibody prior to vaccination. These infants were therefore excluded from the main

analysis, leaving 474 infants (254 SP, 220 placebo).

Following vaccination, 458/474 (97%) infants achieved a concentration of measles antibody

equal to or above the protective threshold, and the proportion of infants unprotected was

similar (3.1% IPTi, 3.6% placebo) in both groups. P-values for the formal test of non-

inferiority in both the intention to treat (ITT) and according to protocol (ATP) analyses were

very small (≤ 0.01), indicating that the difference (SP minus placebo) in proportions

unprotected was not greater than the defined clinical threshold of 5%. The upper 99%

confidence limit was <5%, making it possible to state with a high degree of confidence that

IPTi-SP does not impair serological responses to measles vaccine. The two statistical

methods that were used to adjust for the cluster design of the study produced very similar

results, and the confidence limits from both methods agreed closely. Reverse cumulative

curves were similar for both the IPTi-SP and placebo groups.

23

Yellow fever

Unfortunately, many of the samples selected for yellow fever had insufficient volumes for

testing. Additionally, there was a miscommunication with the lab about the dilution, which

further reduced the available samples to only 136 (64 in placebo and 72 in SP), of which

only 37 had matching pre-vaccination samples (17 in placebo and 20 in SP).

Owing to the very small sample size and numerous complicating factors concerning the

absolute antibody level for protection, the analysis was limited to a comparison of the two

groups only using the post-immunization samples and for the entire cohort (not excluding

any of the children with inconclusive replicate samples or detectable or protective antibody

levels prior to immunization). Two different methods (t-test and generalized estimating

equation GEE) were used to adjust for clustering and both gave similar results. A t-test

analysis comparing the proportions protected in the two arms ignoring clustering was also

conducted.

133/136 (97.8%) children had a yellow fever antibody titre at or above the protective

threshold in their post vaccine samples. The p-values for the formal test of non-inferiority

were small across all three methods (adjusting and not for clustering) confirming the

rejection of the null hypothesis and that the difference in proportions unprotected was

significantly greater than 10% in the SP group. The actual difference SP-placebo found was

4.21%; p=0.004 (GEE), 3.13%;p=0.0003 (t-test ), 4.17%; p=0.01 (t-test ignoring clustering).

The upper confidence limits were consistently less than 10% indicting that the intervention

did not impair the serological responses to yellow fever vaccine.

Comments (WHO Advisory Committee)

A surprisingly high proportion (97%) of infants achieved protective levels of measles

antibody post vaccination*. The augmented post-vaccination response in infants with

detectable antibody pre-vaccination is more suggestive of previous exposure to measles than

persistence of passively acquired immunity. Despite failing to reach the calculated sample

size of 500 per group, a statistically robust result has been achieved with this data.

* This was subsequently discussed with the laboratory, and is likely to reflect reduced

specificity of the PRN assay used at the time.

Conclusions (WHO Advisory Committee)

Serological data from the Navrongo study strongly suggest that IPTi with SP does not have

an adverse impact on serological responses to measles vaccine.

Taking into consideration the analysis of the limited data that are available and the

difficulties with its interpretation, the reverse cumulative distribution functions are very

reassuring and suggest that there is no negative interference of SP on yellow fever

vaccination. The analysis not allowing for clustering produces similar (although more

conservative) results as the other methods, which confirms rejection of the null hypothesis

of a greater than 10% difference.

24

Manhiça, Mozambique

Introduction

This was an individually randomized, controlled comparison of IPTi-SP and placebo given

at the time of DTP2, DTP3 and measles vaccination. Serological responses were measured

in relation to all EPI vaccines except Haemophilus influenzae and yellow fever, since these

are not included in the Mozambique vaccination schedule.

Results

For detailed results see Annex: Final Report Manhiça (May 17th 2006).

Measles

Of 1503 children randomized, 748 received SP and 755 received placebo. Paired (pre- and

post-vaccination) samples were available for 624 infants (308 SP, 316 placebo). Post-

vaccination geometric mean antibody titres (GMT) for 131 infants with detectable levels of

measles antibody prior to vaccination were higher (see statistical report) than the post-

vaccination GMTs in infants with undetectable levels of measles antibody prior to

vaccination. Infants with detectable levels of measles antibody pre-vaccination were

therefore excluded from the main analysis, leaving 493 infants (254 SP, 239 placebo).

Following vaccination, 461/493 (93.5%) infants achieved a concentration of measles

antibody equal to or above the protective threshold, and the proportion of infants

unprotected was similar in both groups (6.7% IPTi, 6.3% placebo). For both the ITT and

ATP analyses, the formal test of non-inferiority was significant (p ≤ 0.03) at the 5% level

and the upper limit of the 90% confidence interval for the difference did not exceed 5%,

indicating that IPTi-SP had no adverse effect on responses to measles vaccine. Reverse

cumulative distribution functions were similar for both the IPTi-SP and placebo groups.

Other EPI antigens (DTP, polio serotypes 1 and 3, hepatitis B)

688 serology samples were available for statistical analysis. Complete data (on all EPI

antigens) were available for 237 infants. The proportion of infants achieving protective titres

post-vaccination was similar in the IPTi-SP and placebo groups for diphtheria, tetanus, polio

serotypes 1 and 3, and hepatitis B. The test of non-inferiority, with a 10% threshold, was

significant in each case, indicating that the difference (SP minus placebo) in the proportion

of infants that did not attain protective antibody concentrations was not greater than the

defined clinical threshold of 10%. There are no known serological correlates of protection

for pertussis. For all antigens, post-vaccination geometric mean titres (GMTs) and reverse

cumulative distribution functions were similar in the IPTi-SP and placebo groups.


Measles

As for Navrongo, a high proportion (93.5%) of infants achieved protective levels of measles

antibody post vaccination (see section on measles PRN, below). The augmented post-

vaccination response in infants with detectable antibody pre-vaccination is more suggestive

of previous exposure to measles than persistence of passively acquired immunity. Despite

failing to reach the calculated sample size of 500 per group, a statistically robust result has

been achieved with this data.

25

Other EPI antigens

The data look very reassuring.


Serological data from the Manhiça study strongly suggest that IPTi with SP does not have an

adverse impact on serological responses to measles, diphtheria, pertussis, tetanus, polio or

hepatitis B vaccines.

26

Bungoma, Kenya

Introduction

This study was an individually randomized, controlled comparison of IPTi-SP and placebo

given at the time of DTP2, DTP3 and measles vaccination. Serological responses were

measured in relation to all EPI vaccines except yellow fever. The study was sponsored by

WHO/TDR, and had been running for over a year when the decision (approved by the WHO

and local Kenyan Ethical Review Committees) was made to expand the sample size in order

to collect EPI serology data. The study took place in a busy maternal and child health clinic

in western Kenya, many of its short-comings reflect its "real-world" setting, and for this

reason it might most accurately be described as a community effectiveness study. Due to the

relative inexperience of the principal investigator and insufficient clinical monitoring (the

first monitoring visit took place after recruitment of all 934 patients), conduct of the trial

was sub-optimal in a number of important respects, which subsequently raised doubts about

the validity of the clinical and serological data. The main problems were as follows:

Informed consent

The consent form that was used for children in the EPI serology study did not mention the

need for multiple venepuncture, although the procedure was explained to all parents and

guardians. This omission was discussed with the WHO Ethical Review Committee (ERC)

and the local Kenyan Institutional Review Board (IRB). Both Committees considered that

the principal investigator and her team should re-contact all participating parents or

guardians and obtain written affirmation that they had consented to venous blood sampling.

According to the WHO ERC, "lack of documentation of the process cannot be condoned,

but, by re-contacting each mother and obtaining an affirmation from them of the consent that

they had provided, this omission is being mitigated". Written affirmation of consent was

obtained from >90% of parents or guardians.

Drug dosing and allocation

The clinical monitor discovered half tablets in some of the unused randomization envelopes,

although each envelope should have contained a complete tablet. It subsequently transpired

that, at the time of randomization, WHO/TDR had placed half tablets in some of the

envelopes when it appeared that they might run out of placebo. From the monitor's report, it

appears that a total of five children had been significantly under-dosed as a consequence. All

of the unused study drugs (SP or placebo) were subsequently sent to London, where 50%

(84 tablets) were selected for analytical determination of content. The contents were verified

against the randomization code by an independent statistician, and allocation was found to

be correct in 100% of cases.

Database

The database was in disarray at the time of the first monitoring visit, as the data manager

had been absent for several months. All of the data pertinent to the EPI serology study were

subsequently source verified by an external monitor and double-entered into a database that

had been constructed by an experienced external data manager.

27

In view of these and other concerns, the Committee concluded that it would not be

appropriate to include data from the Bungoma study in a pooled analysis of EPI serology

along with data from the other IPTi study sites. They did, however, think that it was

appropriate to review and report on the data since: a). Blood samples had already been taken

from human subjects; b). Serological tests had already been carried out; c). The Bungoma

study represented a unique opportunity to obtain data on serological responses to H.

influenzae in infants given IPTi-SP. d). The study provided serological data from a different

geographic setting (Kenya) from that of the other two IPTi-SP serology studies

(Mozambique and Ghana).

The measles PRN tests for the Bungoma and subsequent serology studies were carried out

using a modified and improved standard operating procedure. An interim analysis was

performed on the measles results that were available as of January 2006 and this was used in

the Advisory Committee's Interim Report, July 2006. A revised final analysis including all

the measles results was completed in January 2007.

Results

For detailed results, see Final report Bungoma Final Report May 17, 2006 and updated

Measles Report January 31, 2007.

Measles

Measles serology data were available for 353 children (163 placebo and 190 SP) only, and

not 500 as originally planned. All 353 children were included in the ITT analyses. From

the ATP analyses children were excluded for not having received all three drug doses.

The GMC post vaccination was similar in both treatment groups.

Ninety-five children had detectable antibody concentrations in their pre-vaccination sample,

of which 17 had antibody concentrations above the protective level of 120 IU/l. Excluding

those with detectable concentrations pre-vaccination left 258 children. Following

vaccination, 222/258 (86.0%21) achieved a concentration of measles antibody equal to or

above the protective threshold. The proportion of infants unprotected was similar in both

groups (13.71% placebo; 14.18% SP).

For both the ITT and ATP analyses, the formal test of non-inferiority was non-significant

with a 5% threshold (p ≥ 0.15) and the confidence intervals are very wide reflecting the

inadequate sample size. Reverse cumulative curves were, however, similar for both the SP

and placebo groups.

Other EPI antigens (DTP, polio serotypes 1 and 3, Haemophilus influenzae b, hepatitis

B)

429 serology samples were available for statistical analysis. The proportion of infants

achieving protective titres post-vaccination was similar in the IPTi-SP and placebo groups

for diphtheria, tetanus, polio serotypes 1 and 3, Haemophilus infuenzae b and hepatitis B.

The test of non-inferiority, with a 10% threshold, was significant (p≤ 0.001) in each case,

indicating that the difference (SP minus placebo) in the proportion of unprotected infants

not greater than 10%. There are no known serological correlates of protection for pertussis.

21 This provides further confirmation of the increased specificity of the new SOP compared to that used for the

Navrongo and Manhica studies in which seroconversion was 97% and 94% respectively.

28

For all antigens, post-vaccination geometric mean titres (GMTs) and reverse cumulative

curves were similar in the IPTi-SP and placebo groups.

Of 411 infants in the ITT analysis with complete data on all EPI antigens, 29.9% (63/211) in

the IPTi-SP group had sub-protective responses to one or more antigens, compared to 27.5%

(55/200) in the placebo group, a non-significant difference of 2.4%.


Measles

The proportion of infants (86%) achieving post-vaccination concentrations of measles

antibody equal to or above the protective threshold is comparable to that observed in other

populations. The Bungoma study was substantially under-powered for measles, so the non-

significance of the test of non-inferiority is not surprising. The reverse cumulative

distribution functions are reassuring, however, since curves for SP and placebo are closely

aligned at the protective level of 120 IU/L and across a wide range of antibody

concentrations.

Other EPI antigens

The non-inferiority tests are significant (p ≤ 0.001), allowing rejection of the null hypothesis

that SP has an adverse impact on serological responses to EPI antigens. The reverse

cumulative distribution functions are reassuring for all antigens. The similarity between the

intention to treat (ITT) and according to protocol (ATP) analyses, the proportion of infants

attaining the protective level for each EPI antigen and the comparison of the SP and placebo

groups do not suggest that there are specific problems with the dataset.


Data from the Bungoma study suggest that IPTi-SP does not have an adverse impact on

serological responses to diphtheria, tetanus, pertussis, polio serotypes 1 and 3, Haemophilus

influenzae b and hepatitis B vaccines.

Given that the Bungoma analysis is substantially under-powered for measles, the non-

significance of the test of non-inferiority is not surprising. This combined with the

difficulties encountered implementing the trial limit the ability of the Committee to make a

strong conclusion. However, with these provisos, on the basis of the available results from

Bungoma, the Committee finds no reason to believe that there is any negative impact of SP

when given with measles vaccination.

29

Kisumu, Kenya

Introduction

This was an individually randomized, controlled comparison of three IPTi drug groups, SP-

ART, AQ-ART, and LapDap and a placebo group. The target sample size for each of the

four groups was 37922

. The interventions were given at the time of DTP2, DTP3 and

measles vaccination. Serological assessment was conducted for all of the EPI antigens -

DTP, polio, measles, hepatitis B and Haemophilus influenzae b which are in the national

immunization schedule in Kenya. This was the only trial to assess the serological responses

of IPTi given with Hib vaccine.

Results

For detailed results see Final report Kisumu, March 17, 2009.

Measles

1,516 children were enrolled in the study. Paired measles serology data was only available

for 1,122. Of these, 284 were in placebo, 285 in SP-ART, 293 in AQ-ART, and 260 in

LapDap groups. All 1,122 children were included in the ITT analyses. Children not having

received all three drugs were excluded from the ATP analyses.

The ratios comparing GMC post vaccination titres for each of SP-ART, AQ-ART, and

LapDap to the placebo group were not significantly different from 1, or from one another.

The same result was observed for: i) all children, ii) children without protective measles

antibody level pre-vaccination; and iii) children with undetectable concentrations pre-

vaccination.

Following vaccination 95.1% achieved a concentration of measles antibody equal to or

above the protective threshold of 120 IU/L. The proportion of infants unprotected was

5.24% placebo; 6.25% SP-ART; 5.88% AQ-ART; and 1.76% LapDap. Test of non-

inferiority rejected the null hypothesis that the difference (ITPi treatment minus placebo) in

proportions unprotected is 5% or more. In the ATP analyses the actual differences were SP-

ART 1.03% (p=0.03); AQ-ART 1.25% (p=0.03) and LapDap -3.09% (p<0.0001), providing

evidence to suggest that all three IPTi drugs are not inferior to placebo. This is further

supported by the reverse cumulative distribution functions which are very similar.

Other EPI antigens (DTP, polio serotypes 1 and 3, HepB, and Hib)

Serology data on any one of the antigens was available for a total of 1,135 children for the

ITT and 1,028 for the ATP analysis. The target sample size for each group and each antigen

was 250 children. Number of samples tested:

22 The Kisumu trial was designed with a sample size of 379 per arm at the beginning. When the serology study

was added the study was unable to increase the sample size to 500 per arm for budgetary and operational

reasons.

30

TABLE 9

Number of samples tested by antigen

Placebo SP-ART AQ-ART LapDap TOTAL TOTAL in ATP

Diphtheria 259 255 254 238 1,006 913

Tetanus 179 168 180 173 700 636

Pertussis toxin 161 157 154 151 623 563

FHA 235 220 222 216 893 813

Hib 251 252 255 239 997 897

Polio Type 1 249 240 252 227 968 880

Polio Type 3 249 240 252 227 968 880

Hepatitis B 68 52 59 59 238 222

Complete data on all antigens was available on 107 children.

For diphtheria, tetanus, Hib, and pertussis toxin the GMC after vaccination was similar in

the four treatment groups in both ITT and ATP analyses. For Hep B there was evidence to

reject the null hypothesis of equal GMC between all four groups.

The null hypothesis that the difference (ITPi treatment minus placebo) in proportions

unprotected is more than 10% was rejected in the AQ-ART and LapDap groups for

diphtheria, tetanus, Hib, HepB, and polio type 1. For polio type 3 the null hypothesis that the

difference in proportion unprotected is at least 10% could not be rejected for the LapDap

and SP-ART groups for either ITT or ATP analyses.

The reverse cumulative curves were reassuring except for HepB, possibly as a result of the

small sample size available for this antigen.

To investigate HepB responses further a post-hoc analysis using 100IU/L (the level at which

long term immunity is conferred) instead of 10IU/L (level for seroconversion) as a cut-off.

The null hypothesis of inferiority of the SP-ART and LapDap groups compared to placebo

for both the ITT & ATP analyses could not be rejected. The comparison of AQ-ART with

placebo found evidence to reject the null hypothesis of inferiority in both ITT and ATP

analyses.

31


Measles

Despite the difficulties collecting the samples and with the caveat that the children included

are a representative sample, the Committee found it reassuring that the results for the four

study groups were very similar in the protective levels of measles antibodies.

Other EPI antigens

The post-hoc analysis of HepB using 100IU/L was seriously marred by the small sample

size. However, there was no evidence of any problem with SP-ART, some evidence that

AQ-ART might be better than placebo, and some very weak evidence that LapDap might be

worse than placebo (the proportions under 100IU/L being quite high). However, nothing

more definite can be said owing to the lack of power.

Overall, the Committee was impressed with the robustness of the response of all the

antigens across all the drug combinations.


In spite of the much smaller sample sizes than expected, the Committee was satisfied that

the null hypothesis was supported by the results and that the three drug combinations, SP-

ART, AQ-ART, and LapDap, were not inferior to placebo.

32

Kilimanjaro, Tanzania

Introduction

This was an individually randomized, controlled comparison of three IPTi drug groups, SP,

MQ, and LapDap and a placebo group. The interventions were given at the time of DTP2,

DTP3 and measles vaccination. Serological responses were measured for measles vaccine

only.

Results

For detailed results see Second Draft (actually Final Report) Kilimanjaro, November 21,

2008.

Measles

2,419 eligible were enrolled in the study, and paired pre and post samples were collected

from 1,812 children. Due to insufficient volume or sub-optimal quality of the samples,

paired measles serology data was only available for 1,538 children. There were no

significant differences between treatment groups in the samples lost due to sample quality or

quantity. Of the 1,538 children usable pre and post samples, 397 were in placebo, 374 in SP,

380 in MQ, and 387 in LapDap groups. All 1,538 children were included in the ITT

analyses. For the ATP analyses children were excluded for not having received all three

drug doses.

The GMC values post-vaccination were similar in all four treatment groups.

161 children had detectable measles antibody concentrations in their pre-vaccination

sample. Excluding those left 1,377 children. Following vaccination, 1296/1377 (94.1%)

achieved a concentration of measles antibody equal to or above the protective threshold. The

proportion of infants unprotected was similar in both groups (5.70% placebo; 5.18% SP;

5.52% MQ; and 7.06% LapDap).

Formal tests of non-inferiority, of the null hypothesis that the difference (ITPi group minus

placebo) in proportions unprotected is 5% or more, rejected the null hypothesis in each case

in ITT analyses. Owing to the smaller than expected numbers of children included in this

analysis and the resulting loss of power the evidence is not sustained at the 1% significance

level for the LapDap and placebo group comparison.

In the ATP analyses (further 62 children were excluded for not having received all three

drug doses, leaving 1,315) the formal test of non-inferiority (for all three comparisons),

rejected the null hypotheses SP ( treatment minus placebo difference in proportion

unprotected -0.47%; p=0.002), MQ (-0.48%; p=0.003) and LapDap (1.42%; p=0.03) were

inferior to placebo.

The reverse cumulative distribution functions for all interventions and placebo were very

similar.

33


Measles

The Committee agreed that all three formal tests of non-inferiority (the null hypothesis that

the difference in proportions unprotected between each of the investigational products with

placebo is 5% or more) give results that provide strong evidence rejecting the null

hypothesis for SP and MQ. However, due to the smaller than expected numbers of children

included in this analysis and the resulting loss of power the evidence found is not sustained

at the 1% significance level for the LapDap and placebo group comparison.


The Committee was satisfied with the robustness of the results and in particular the

concordance of the reverse cumulative distribution functions. Taken together the Committee

concludes that this evidence supports that IPTi treatment with SP, MQ, and LapDap in this

study had no influence on the serological response to measles vaccination.

Documents

WHO Advisory Committee on serological responses to ...• all cause hospital admissions in the first year of life by 23% (95% CI: 10.0%; 34.0%) (noting that admissions were not, however,