WHO/BS/2015.2272 ENGLISH ONLY EXPERT …...R1, 2011 performed consistently in the commercially available Vacczyme ELISA. In this ELISA, the GM potency of candidate IS 10/126 was calculated

WHO/BS/2015.2272

ENGLISH ONLY

EXPERT COMMITTEE ON BIOLOGICAL STANDARDIZATION

Geneva, 12 to 16 October 2015

Requests to initiate new WHO reference material projects for vaccines and

related substances

Document prepared by the WHO Secretariat, based on inputs from WHO Collaborating Centres

supporting biological standardization activities.

Note:

This document has been prepared for the purpose of inviting comments and suggestions on the

proposals contained therein, each of which will be considered by the Expert Committee on

Biological Standardization. The proposals have not yet been endorsed by the Expert Committee.

Comments on the proposals MUST be received by 14 September 2015 and should be addressed

to the World Health Organization, 1211 Geneva 27, Switzerland, attention: Technologies,

Standards and Norms (TSN). Comments may also be submitted electronically to the Responsible

Officer: Dr David Wood ([email protected]). The outcome of the deliberations of the Expert

Committee will be published in the WHO Technical Report Series.

© World Health Organization 2015

All rights reserved. Publications of the World Health Organization are available on the WHO web site (www.who.int) or can

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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.

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WHO/BS/2015.2272

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Introduction

The provision of global measurement standards is an important normative activity of WHO.

Biological reference preparations that are accepted internationally enable the efficacy, quality, purity

and safety of very many biological medicines, used in the prevention, treatment or diagnosis of

disease or conditions, to be stated in a common language worldwide. International biological

reference standards support the use of many biological and immunological assays for the quality

control of a wide range of biologicals including therapeutics, blood-derived products, vaccines and

immunological products of traditional types as well as those derived from modern biotechnological

approaches. They also have important applications in the standardization of materials and

approaches used in medical diagnostics such as diagnosing disease, monitoring therapy, blood safety,

and public health applications (e.g. monitoring immune status, screening for disease or susceptibility)

or otherwise characterizing biological material from individuals.

WHO biological reference standards are widely used in the development, evaluation, standardization

and control of products by industry; by regulatory authorities; and also in biological research in

academia and scientific organizations. They play a vital role in facilitating the transfer of laboratory

science into worldwide clinical practice and the development of safe and effective biologicals.

The timely development of new reference materials and standards is critically important to harness

scientific developments for new biologicals. At the same time, the active management of the

existing inventory of reference preparations requires a carefully planned programme of work to

replace established materials before the stock of containers, which comprises the standard, is

exhausted.

Considerations for assignment of priorities to development of WHO International Biological

Measurement Standards or Reference Reagents have been published (WHO TRS 932, Annex 2,

Appendix 1, 2005). These considerations are used as guiding principles by the Secretariat and the

WHO Collaborating Centres to develop a proposed programme of future work. To facilitate and to

improve transparency in the priority setting process, a simple tool has been developed which

describes the salient features of each new project proposal.

This document provides a means for the Committee and other stakeholders to review and comment

on new proposals that are under consideration. The proposals in this document

(WHO/BS/2015.2272) cover requests to initiate new projects in the areas of vaccines and related

substances (Appendix 1).

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Appendix 1 Vaccines and related substances

Proposed new projects

Proposal (title) 1st International Standard for human anti-Vi polysaccharide serum

Proposer (name of Institution)

NIBSC Principal contact Sjoerd Rijpkema , Bacteriology

Rationale Typhoid is a major cause of illness and death among children in developing countries (DC). WHO produced a position paper on immunisation against typhoid and it supports typhoid vaccination campaigns in DC. Vaccination of local populations has become economically feasible now vaccine manufacturers in DC have started producing Vi polysaccharide (PS) conjugate vaccines (ViCVs). New ViCVs have been licensed or are progressing through clinical trials. Manufacturers use in-house or commercially assays to characterise the immuno-reactivity of ViCVs. Recently, CBER issued a purified IgG anti-Vi PS standard, prepared at NIH, which contained 33 µg specific IgG per ampoule. These developments emphasize the need to for an international standard (IS) for anti-Vi PS antibodies.

Anticipated uses and users

The IS will be used by diagnostic laboratories (commercial, regional, national) and manufacturers to calibrate immunoassays. Estimated use is approx. 40 vials per year.

Source/type of materials The candidate IS 10/126 is a freeze dried preparation of a pool of nine sera from volunteers who took part in a Ph II clinical trial of Vi PS-tetanus conjugate. The individual samples, the pooled material and candidate IS 10/126 are positive for anti-Vi PS IgG. App. 1600 ampoules are available.

Outline of proposed collaborative study

Nine laboratories participated in CS 507 designed to validate candidate IS 10/126. The outcome of CS507 showed that candidate IS 10/126 and CBER standard Vi-IgGR1, 2011 performed consistently in the commercially available Vacczyme ELISA. In this ELISA, the GM potency of candidate IS 10/126 was calculated as 0.65 (GCV 15%; n=3) relative to Vi-IgGR1, 2011. However, results from in-house ELISAs (e.g. Vi 05 ELISA published by Szu et al.) showed a high variability in the relative potency of candidate IS 10/126, depending on the ELISA format and the participating laboratory. Results were presented in 2014, and ECBS concluded that data generated by the Vacczyme ELISA, where assay information is not in the public domain, are insufficient to establish candidate IS 10/126 or assign a unitage relative to CBER standard Vi-IgGR1, 2011. ECBS requested further work to determine the cause of inter-laboratory and inter-assay variation. To accommodate ECBS’s view, follow-up CS507B has been designed: 5 participants were selected from CS507 to analyse candidate IS 10/126, Vi-IgGR1, 2011 and 9 individual anti-Vi IgG positive sera in ELISA. In-house ELISAs, where information is accessible to third parties (e.g. Vi05 ELISA), will be used alongside the Vacczyme ELISA. Latter assay will be distributed to all participants. The aims of CS507B are: 1) To assess the suitability of the candidate IS 10/126 as a WHO standard for anti-Vi PS IgG (human) 2) To compare the reactivity of the candidate IS 10/126 and the CBER standard

Vi-IgGR1, 2011 in various ELISAs. 3) To assess the commutability of the freeze-dried anti-Vi PS IgG reference

materials in various ELISAs with nine individual anti-Vi IgG positive sera.

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Issues raised by the proposal

• Will both reference reagents and the individual sera give comparable results in the various ELISAs? • Are both reference reagents commutable? • Can specific ELISAs reagents or procedures (e.g. antigens, coating conditions, buffers) be identified as the cause of variability? • Can specific factors of the reference reagents (e.g. matrix, anti-LPS antibodies) be identified as the cause of variability? • BMGF to fund CS507B in its entirety through the Coalition against Typhoid • Validation of IS 10/126 now delayed until at least October 2016

Action required • Sign MTAs with NVGH for donation of 9 individual sera from volunteers of a Phase

I clinical trial with ViCV. • CBER to release reference reagents Vi05 and Vi-IgGR1, 2011 for use in CS507B • For ECBS to take note of the (modified) plans.

Proposer's project reference

BAC00002 Date proposed: June 2015

CONSIDERATIONS FOR ASSIGNMENT OF PRIORITIES (TRS932)

Approval status of medicine or in vitro diagnostic method

• The Vacczyme ELISA and several in-house ELISAs (e.g. Vi 05 ELISA) have been used to analyse the immunogenicity of ViCVs in clinical trials.

• Vi-IgGR1, 2011 has been used to calibrate ELISAs.

Number of products or methods

Several in-house Vi ELISAs have been developed, usually in association with the development of a ViCV. To date only one commercial Vi ELISA, the Vacczyme ELISA, is available.

Public health importance

At present, typhoid is endemic in most developing countries. Large segments of the population lack access to safe water supply and basic sanitation services. In addition, there are limited programs for detecting carriers and restricting them from food-handling.

Global importance

In 2008, the WHO estimated that typhoid fever causes 216,000–600,000 deaths annually. Most of the mortality occurs in developing countries and 80% takes place in Asia. Hospital-based mortality ranges from 0–13.9% and among children mortality can be as high as 14.8%. In India, the estimated burden of typhoid in 2 year olds was 89 per 100,000 child-years

Global need from regulatory & scientific considerations

There are minimum requirements for the amount anti-Vi PS IgG antibodies generated by immunization with ViCVs. An anti-Vi IgG standard will limit inter-assay variation and increase comparability of the immunogenicity (phase II clinical trials) of ViCVs.

ECBS outcome [BLANK]

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Proposal (title) 1st International Standard Panel for human anti-iNTS O-antigen polysaccharide serum


NIBSC Principal contact Sjoerd Rijpkema

Rationale Invasive nontyphoidal Salmonella disease (iNTS) is caused by Salmonella enteric serovars Typhimurium (O4,5 LPS) and Enteritidis (O9 LPS). iNTS is a leading cause of bacteremia in sub-Saharan Africa, particularly in infants and immune-compromised individuals, it has a high case fatality rate and multidrug resistance hampers effective treatment. Vaccine developers along with manufacturers in developing countries have started producing bivalent vaccines containing O4,5 and O9 antigens representing these serovars. These vaccines will enter clinical trials within 2 years. Field studies have shown that increased serum levels of anti-O IgG in young children reduce the chances of reinfection with Typhimurium. Anti-O IgGs are bactericidal in vitro Presently, in-house or commercially available antisera and immune assays are used to characterise the immuno-reactivity. Given the potential of an iNTS vaccine for controlling disease there is a need to for an International Standards for anti-O4,5 and anti-O9 serum IgG (human).


Human anti-O4,5 and anti-O9 standards will be used by diagnostic laboratories and National Control Laboratories (NCLs), kit manufacturers and academia . Estimated use is approx. 40 vials per year.

Source/type of materials Sera from volunteers taking part in Phase I clinical trials will be collected by informed consent. The individual samples and the pooled material will be screened for IgG reactive with O4,5 or O9 antigen. Pooled serum is filled and freeze dried. Approx. 1500 ampoules will be produced.


Several vaccine developers/manufacturers will be approached as sources of clinical samples. These include: Sclavo Behring Vaccine Institute for Global Health (bivalent outer membrane), Bharat Biotechnology / Center for Vaccine Development - Univ Maryland Baltimore (bivalent conjugate), and Center for Vaccine Development - Univ Maryland Baltimore (oral attenuated).

The aims of the CS are: • To assess the suitability of the candidate standards as an IS for human anti-O4,5 and anti-O9 PS antibody, respectively. • To assess the level of cross reactivity between the O-antigens • To compare the reactivity of the candidate standards in ELISA. • To assess the reactivity of the candidate standards in various immunoassays

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• Standards will be used to compare immunogenicity of vaccines in development as well as for standardisation of sero-epidemiological field studies. • Individuals repeatedly infected with S. Typhimurium or Enteritidis will develop anti-O4,5 and anti-O9 serum antibodies, respectively. This can cause high background levels of anti-LPS Igg in sera of volunteers.

Action required Integration into NIBSC work plan and for ECBS to endorse proposal


TBC Date proposed: May 2015



Several iNTS vaccines to go into clinical trial within two years. Supported by vaccine developers, manufacturers and Wellcome Trust.


App 4 vaccines in development.


iNTS is a leading cause of bacteremia in sub-Saharan Africa, particularly in infants and immune-compromised individuals, it has a high case fatality rate and multidrug resistance hampers effective treatment.

Global importance

iNTS is a leading cause of bacteremia in sub-Saharan Africa, particularly in infants and immune-compromised individuals, it has a high case fatality rate and multidrug resistance hampers effective treatment.


Given the need for an iNTS vaccine to control the disease there is a need for an International Standards for anti-O4,5 and anti-O9 serum IgG (human).


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Proposal (title) 1st International Standard for human anti-O2 polysaccharide serum



Rationale Salmonella enterica Paratyphoid A, along with Typhi, causes illness and death among children in developing countries (DC). In the WHO produced a position paper on immunisation against typhoid, it is envisaged that vaccination in many DC will also be required for control of paratyphoid fever, which is indistinguishable from typhoid fever. Vaccine developers along with manufacturers in DC have started producing O2 PS components specific for paratyphoid to be combined with typhoid vaccines. These vaccines should be in clinical trials in the next 12-18 months with registration and WHO PQ anticipated by 2021-2022. Presently, in-house or commercially available antisera and immune assays are used to characterise the immunoreactivity. Given the importance of this vaccine for controlling enteric fever there is a need to for an International Standard for human anti-O2 PS antibodies.


The human anti-O2 standard will be used by diagnostic laboratories and National Control Laboratories (NCLs), kit manufacturers and academia . Estimated use is approx. 40 vials per year.

Source/type of materials Sera from volunteers taking part in Phase I clinical trials will be collected by informed consent. The individual samples and the pooled material will be screened for IgG reactive with O2 antigen. Pooled serum is filled and freeze dried. Approx. 1500 ampoules will be produced.


Several vaccine developers/manufacturers can be approach as sources of clinical samples. These include: Biological E / Sclavo Behring Vaccine Institute for Global Health (conjugate), Bharat Biotechnology / Center for Vaccine Development - Univ Maryland Baltimore (oral attenuated), and International Vaccine Institute and its partners (conjugate). ). The aims of the CS are: • To assess the suitability of the candidate standard as an IS for human anti-O2 PS antibody • To compare the reactivity of the candidate standard and in-house standards in ELISA. • To assess the reactivity of the candidate standard in various immunoassays

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• The standard will be used for relative comparisons of vaccine immune responses elicited by vaccines in development as well as assessment of field studies. • Individuals repeatedly infected with S. Paratyphi A will develop anti-O2 LPS serum antibodies. Thus some background activity may be present.






Several paratyphoid/typhoid vaccines to go into clinical trial within two years.


>5 vaccine formulations?


Supported by enteric fever vaccine manufacturers and Wellcome Trust. Need foreshadowed in WHO position paper on typhoid fever.

Global importance

Paratyphoid A, along with Typhi, causes illness and death among children in DCs. The incidence of Paratyphoid A is likely to increase with the advent of Typhoid conjugate vaccines.


Given the need for a paratyphoid/typhoid combination vaccines there is a need for an International Standards for anti-O2 LPS serum IgG (human).


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Proposal (title) 1st International Standard Panel for human anti-Shigella O-antigen polysaccharide serum



Rationale Shigella serotypes are a major global cause of morbidity and mortality. Shigella flexneri and Shigella sonnei are responsible for > 125 million cases of moderate to severe diarrhea cases per year, mostly in children under 5 years of age in sub-Saharan Africa and South Asia. Several organizations are developing 4- to 6- valent vaccines to cover the immunodominant O-antigens of the most epidemiologically relevant serotypes. Several of these vaccines are already in early clinical trials. For Shigella sonnei, an O-antigen antibody level has been identified which is protective. Presently, in-house or commercially available antisera and immune assays are used to characterise the immunoreactivity. Given the potential of a multivalent Shigella vaccine for controlling disease there is a need for International Standards for human anti-O-antigen PS antibodies reflecting the most epidemiologically relevant serotypes: S. sonnei, S. flexneri 2a, 3a and 6.


The panel of human anti-O-antigen standards will be used by diagnostic laboratories and National Control Laboratories (NCLs), kit manufacturers and academia. Estimated use is approx. 100 vials per year.

Source/type of materials Sera from volunteers taking part in Phase I clinical trials will be collected by informed consent. The individual samples and the pooled material will be screened for IgG reactive with Shigella O antigen. Pooled serum is filled and freeze dried. Approx. 1500 ampoules will be produced.


Several vaccine developers/manufacturers can be approach as sources of clinical samples. These include but are not limited to: Sclavo Behring Vaccine Institute for Global Health (outer membrane), Walter Reed Army Institute of Research (oral attenutated), Center for Vaccine Development - Univ Maryland Baltimore (oral attenuated), GlycoVaxyn (bioconjugate), Institut Pasteur (conjugate), Tel Aviv Univ (conjugate) and PATH funded projects. The aims of the CS are: • To assess the suitability of the candidate standards as an IS for human anti-O-antigen PS antibody.

To assess the level of cross reactivity of the candidate standards in O antigen ELISAs for S. sonnei, S. flexneri 2a, 3a and 6

• To compare the reactivity of the candidate standards in ELISA. • To assess the reactivity of the candidate standards for human anti-O-antigen standards in various immunoassays

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• Standards will be used for relative comparisons of vaccine immune responses elicited by vaccines in development as well as assessment of field studies. • Individuals with historic Shigellosis will develop anti-O-antigen/anti-LPS antibodies that will react with S. sonnei, S. flexneri 2a, 3a and 6 O antigen.

Levels in convalescent sera have been linked with protection against re-infection.






Several Shigella vaccines have entered clinical trials or will go into clinical trials soon.


7


See ‘global importance’. This work will be supported by vaccine developers, manufacturers and PATH.

Global importance

Shigella serotypes are a major global cause of morbidity and mortality. Shigella flexneri and Shigella sonnei are responsible for > 125 million cases of moderate to severe diarrhea cases per year, mostly in children under 5 years of age in sub-Saharan Africa and South Asia


Given the potential of a multivalent Shigella vaccine for controlling disease there is a need for International Standards for human anti-O-antigen PS antibodies reflecting the most epidemiologically relevant serotypes: S. sonnei, S. flexneri 2a, 3a and 6.


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Proposal (title) First International Standard for Vi polysaccharide


NIBSC Principal contact Sjoerd Rijpkema, Bacteriology

Rationale Several companies, a number of them in developing countries, have started the production and clinical development of Vi polysaccharide (Vi PS) conjugate vaccines (ViCV), some of which have been licensed or are in clinical trials. Thus a variety of ViCVs will become available on the market. A global common standard is needed for the quantification and testing of other quality parameters of Vi PS in ViCVs. There will be no bioassay to measure potency of these vaccines that enables a correlation with or prediction for clinical efficacy. A relative ratio of free polysaccharide against total polysaccharide (free and conjugated polysaccharide), the extent of O-acetylation, and molecular size/mass distribution have been used as important markers for immunogenicity for Vi PS.


Anticipated usage of appr 50-100 ampoules/year by vaccine manufacturers National Control Laboratories (NCLs), kit manufacturers and academia. Thus a fill of 1000-1500 ampoules is reasonable.

Source/type of materials Vi PS from Citrobacter freundii of GMP standard was donated by NVGH (Novartis, Italy). In February 2013, the material was filled and freeze dried at NIBSC and1249 ampoules of 12/244 are available. Ampoules contain a robust loose shrunken cake after freeze drying. The moisture content is 0.14% (CV 38%, n=12) and oxygen content is 0.36% (CV 31%, n=12). The dry weight content determined by gravimetry is 2.9 mg (CV 20%, n=25). The Vi PS content per ampoule was determined by quantitative NMR as 1.91 mg (CV 0.80%, n=6) with a level of O-acetylation of 95% (CV 1.35, n=6). In aspirate analysis, the Vi PS content was determined by HPAEC PAD as 2.38 mg (CV 3.7%, n=4), by Hestrin assay as 1.68 mg (CV 3.1%, n=4) and the level of O-acetylation is 97% (CV 1.2%, n=3). The endotoxin content by LAL assay was 6 IU per vial (range 6-12) or ~0.003 IU per μg Vi PS. A 2nd Vi PS preparation purified from Salmonella enterica subspecies Typhi is being pursued for use as a standard.


The participants will be vaccine manufacturers and NCLs. The CS is likely to be quite small: 6-10 participants. Following a decision to assign unitage by qNMR, the CS will establish whether the standard can be used as a quantitative standard in different assays (NMR for O-acetyl and backbone N-acetyl galacturonic acid repeating unit content, Hestrin colorimetric assay for O-acetyl content, and HPAEC-PAD for backbone saccharide content), and if it is ‘fit for purpose’ in the determination of these contents in a supplied ViCV. Other quantitative methods to determine the amount of Vi PS, mentioned in the WHO guidelines and pharmacopeias, can also be used. These can be either immunoassays or physicochemical methods. The study will also compare the amount of Vi PS per ampoule by NMR and provide the Uncertainty of Measurement (UoM) derived by combining a statistical analysis with assessments of systematic measurement bias.

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Several ViCVs are licensed or scheduled for licensing and use this material for an IS could be advantageous for Novartis. A: This is not a CoI for NIBSC.

Can misuse of the standard be prevented? A: The standard IFU has wording in place to specifically warn against use of the material in humans.

Vi PS from C. freundii is acceptable as bio-similar? A: Vi PS from C. freundii and Salmonella enterica Typhi are structurally and immunologically identical but the molecular size may differ.

Can the standard be used for molecular weight measurements? A: Yes. This will be a key QC assay for Vi PS.

What is an acceptable UoM for the standard? A: An UoM of around 5% needs to be achieved.

Is the standard suitable as a standard for ViCVs?

Does it make economic sense to split the sample? A: A split in ’reference standard’ and ‘working standard’ (for day to day use) may preserve the material.

Action required ECBS to endorse proposal


BAC00004 Date proposed: ECBS October 2013



Vi PS vaccines are used globally either routinely or to mitigate/prevent epidemics. The ViCV will extend vaccination to infants and could replace the Vi PS vaccine in other age groups. Thus a proper reference is important for the QC these vaccines and to compare products.


App. 6 manufacturers produce Vi PS vaccines and a similar number is predicted for ViCVs.


At present, typhoid is endemic in most developing countries. Large segments of the population lack access to safe water supply and basic sanitation services. In addition, there are limited programs for detecting carriers and restricting them from food-handling.

Global importance

In 2008, the WHO estimated that typhoid fever causes 216,000–600,000 deaths annually. Most of the mortality occurs in developing countries and 80% takes place in Asia. Hospital-based mortality ranges from 0–13.9% and among children mortality can be as high as 14.8%. In India, the estimated burden of typhoid in 2 year olds was 89 per 100,000 child-years


There are minimum requirements for the amount Vi PS per dose of plain or ViCV. In addition the amount of Vi PS in relation to the carrier protein is important for the potency of the vaccine.

ECBS outcome

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Proposal (title) e.g. i) The first International Standard for Clostridium difficile


NIBSC Principal contact Donna Bryan/Fatme Mawas

Rationale Clostridium difficile infection, termed CDI, is caused by colonisation of the human intestine by a Gram-positive bacterium known as C. difficile. Hospitalisation for long periods, intestinal surgery, irritable bowel syndrome, immune-compromised or the use of antimicrobials are risk factors for CDI which can result in a high mortality rate and the risk of recurrence of C. difficile infection presents a burden to both patients and the healthcare system. CDI accounted for 36,000 reported cases in 2010 and over 2,000 deaths in England and Wales during 2009-2011. In the USA this number rises to over ~3 mill new infection/year with over 20,000 deaths. In addition to this CDI is increasingly seen in healthy adults in the absence of antibiotic exposure. C. difficile is an opportunistic pathogen which colonises the gut upon reduction of the natural flora within the gut causing severe enteric infections resulting in a range of gastrointestinal diseases that includes mild diarrhoea, debilitating diarrhoea, pseudomembranous colitis and death. CDI associated disease constitutes a large majority of nosocomial diarrhoea cases in industrialized nations and is mediated by the effects of two secreted toxins, toxin A (TcdA) and toxin B (TcdB). These toxins (TcdA and TcdB) have key toxin-neutralizing epitopes within the carboxy-terminal receptor binding domains (RBDs) and these are the focus of current vaccine development studies. It has been shown in clinical trial studies that patients who develop strong antitoxin antibody responses can clear C. difficile infection and remain disease-free. There are several vaccines currently in various stages of clinical trial studies (Phase I to III), however, there are currently no standards or reference reagents available to standardise immune, functional or cytotoxic assays necessary for the evaluation of efficacy and quality of these vaccines. The presence of a human reference serum with assigned unitage will be very useful for calibrating the various immune-assays used to measure human antibody responses and to reduce variability between testing laboratories or assay kits for measuring human antibody response following immunisation or in hospital setting.


Development of a vaccine against C. diff will require evaluation of vaccine efficacy in clinical trials, where determination of the level of total and toxin neutralising antibody responses could be used as correlates of protection. It is anticipated that a human reference serum will be used in the evaluation of sera from clinical trials and for screening patients for the presence of anti- C. diff antibodies.

Users will be vaccine manufacturers, health care providers and possibly kit manufacturers

Source/type of materials Human Sera will be supplied to NIBSC by a vaccine manufacturer; the samples will be from individual anonymous donations and will be screened for viral markers in accordance with NIBSC standard procedures for filling, before being pooled. If any donations test positive at NIBSC, they will be rejected, and disposed of appropriately.


Material will be sent to laboratories representing manufacturers, academia, and NCLs worldwide. They will be asked to assess the material by their usual method(s) and report the data to NIBSC for statistical analysis. A consensus will be reached on assigning unitage.

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Date proposed:





Global importance


ECBS outcome

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Proposal (title) The first International Standards for meningococcal serogroups W and Y polysaccharides


NIBSC Principal contact Hannah Chan

Rationale Tetravalent conjugate vaccines to prevent disease caused by Neisseria meningitidis serogroups ACWY are used globally. There is currently a 1st IS for serogroup C (MenC) polysaccharide (PS) and a second project is currently underway for the 1st IS for MenA PS (endorsed July 2013) and MenX (endorsed March 2014). The proposed standards for MenW and Men Y will allow the accurate quantification of polysaccharide in both the intermediate PS and bulk conjugate components and final vaccine and complete the set of International Standards used for quantification of PS in meningococcal conjugate vaccines.


This standard will be used by vaccine manufacturers and National Control Laboratories (NCLs).

Source/type of materials The material was donated to NIBSC by Novartis Vaccines: purified polysaccharide of vaccine quality (i.e. low LPS and protein content)


We propose to involve a minimum of 10 laboratories in the Collaborative Study. The laboratories will be made up of NCLs, vaccine manufacturers and if possible a university. The aim of the study will be to determine the appropriateness of using the candidate material to determine MenW and MenY PS in conjugate vaccine samples. Previous collaborative studies for polysaccharide candidates have also been used to assign unitage. However the current proposal is to use quantitative NMR run at NIBSC to assign unitage.


The current MenA and MenX IS project proposes to use qNMR from one laboratory to assign unitage to the candidate reference materials. If this is accepted by ECBS a similar approach will be followed for the MenY and MenW PS. Alternatively the resorcinol assay and HPAEC-PAD method may also be used for quantification of the characteristic galactose and glucose monosaccharide units of the MenW and Men Y polysaccharides respectively.



Date proposed: ECBS 2015


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Three ACWY conjugate vaccines are currently in use, Menactra, Menveo and Nimenrix. Other conjugate vaccines with different valencies, containing W and Y polysaccharide are also in development. They are indicated for use in children in adults and Menveo and Nimenrix will be introduced into the adolescent vaccination schedule in the UK in 2015.


Three tetravalent conjugate vaccines are licensed with others in

development. The International standard has potential use in three

quantitative assays – NMR, HPAEC-PAD and Resorcinol.


Disease incidence from the different serogroups varies from country to country. Whilst particular serogroups have predominated in the past it is unpredictable which will have higher importance in the future. The use of ACWY conjugates is therefore likely to become increasingly common. Disease incidence is highest in infants with a secondary peak occurring in young adults and recently there has been an increase of serogroup W disease in the UK which has prompted the decision to routinely vaccinate adolescents with the ACWY conjugate.

Global importance

Meningococcal disease is found worldwide with severe outbreaks of disease occasionally occurring. Of particular importance is serogroup A disease where it is endemic in sub-Saharan Africa known as the Meningitis Belt. There are plans to replace the current MenA vaccine used in Africa with a multivalent product likely to include groups W and Y PS.


Quantification of the total and free (unconjugated) saccharide in conjugate vaccines is of key importance as indicators of vaccine potency. With the increased use of multivalent conjugates there is a need to accurately quantify each of the different polysaccharides in order to achieve the correct balance of each in the final formulation.


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Proposal (title) 1st International Standard panel of O-antigen polysaccharides from non-typhoidal Salmonella



Rationale Invasive nontyphoidal Salmonella disease (iNTS) is caused by Salmonella enterica serovars Typhimurium (O4,5 LPS) and Enteritidis (O9 LPS). iNTS is a leading cause of bacteremia in sub-Saharan Africa, particularly in infants and immune-compromised individuals, it has a high case fatality rate and multidrug resistance hampers effective treatment. Vaccine developers along with manufacturers in developing countries have started producing bivalent vaccines containing O4,5 and O9 antigens representing these serovars. As several vaccines targeting the O-antigen PS will entering clinical development, a global common standard is needed for the

quantification and testing of quality parameters of O4,5 and O9

polysaccharide used in bioassays to measure potency of these vaccines and to compare the immunogenicity of various vaccines.


Anticipated usage of appr 50-100 ampoules/year by vaccine developers and manufacturers as well as national control laboratories, kit manufacturers and academia. Thus, a fill of 1000-1500 ampoules is reasonable.

Source/type of materials Purified O4,5 and O9 PS from Salmonella enterica serovars Typhimurium and Enteritidis could be obtained from several sources including Bharat Biotechnology / Center for Vaccine Development - Univ Maryland Baltimore and Sclavo Behring Vaccine Institute for Global Health. This material would be of GMP standard. An assessment of freeze drying would need to be carried out by NIBSC prior to filling and this expertise is in-house.


The participants will be vaccine developers/manufactures and national control laboratories and the number is likely to be small. The CS will establish whether the material is ’fit for purpose’. The biochemical, biophysical characterization of the O4,5 and O9 PS will need to be aligned with the current literature. There is currently no TRS defining absolute requirements. Quantitative methods to determine the amount of O-antigen PS, saccharide composition will be standard, and guidelines and pharmacopeias for bacterial PS vaccines should be consulted. The material should be suitable for use in immunoassays or physicochemical methods. The study will assess the amount of O4,5 and O9 PS per ampoule and provide the Uncertainty of Measurement (UoM) derived by combining a statistical analysis with assessments of systematic measurement bias.

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Working with not-for profit organizations will limit CoI.






It is envisaged an iNTS vaccines will be used in sub-Saharan Africa either routinely or to mitigate/prevent epidemics. The proposed bivalent iNTS vaccines (containing Typhimurium and Enteritidis components) will be indicated for vaccination of all ages including infants, and could eventually be combined with Salmonella Typhi vaccines. Thus, a proper reference is important for the QC these vaccines and to compare between products.


At present 3 types of bivalent vaccines are in development (a conjugate, an attenuated oral vaccine and an outer membrane vaccine).


iNTS is a leading cause of bacteremia in sub-Saharan Africa. NTS also causes gastroenteritis in the developed world. Because of non-specific symptoms, diagnosis and treatment of iNTS is difficult. When appropriately diagnosed, treatment is difficult due to increasing antimicrobial resistance that varies location to location.

Global importance

Global burden of disease is estimated to be > 2 million illnesses per year of which > 100,000 will result in death. Presentation is as a febrile illness, with symptoms similar to malaria.


Given the need for an iNTS vaccine to control the disease there is a need for International Standards for O4,5 LPS and O9 LPS.


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Proposal (title) 1st International Standard for O2 polysaccharide from S. enterica Paratyphi A



Rationale Several vaccine developers and developing country manufacturers are producing O2 components specific for paratyphoid to be combined with typhoid vaccines. These vaccines should be in clinical trials in the next 18 months. Thus a number of O2 PS vaccines will become available on the market. A global common standard is needed for the quantification and testing of quality parameters of O2 PS used in bioassays to measure potency of these vaccines and to compare the immunogenicity of various vaccine formulations.



Source/type of materials Purified O2 PS from Salmonella enterica serovar Paratyphi A could be obtained from several sources including Bharat Biotechnology / Center for Vaccine Development - Univ Maryland Baltimore and Biological E / Sclavo Behring Vaccine Institute for Global Health. This material would be of GMP standard. Assessment of freeze drying would need to be carried out by NIBSC prior to filling.


The participants will be vaccine developers/manufactures and national control laboratories and is likely to be quite small. The CS will establish whether the material is ’fit for purpose’. The biochemical, biophysical characterization of the O2 will need to be aligned with the current literature as there is currently no TRS defining absolute requirements. Quantitative methods to determine the amount of O2 PS, saccharide composition will be standard, and guidelines and pharmacopeias for injectable PS should be consulted. The use of this material can be either in immunoassays or for physicochemical methods. The study will assess the amount of O2 PS per ampoule and provide the Uncertainty of Measurement (UoM) derived by combining a statistical analysis with assessments of systematic measurement bias.

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None. Working with not-for profit organizations will limit CoI.



Date proposed: May 2015



It is envisaged the S. Paratyphi A containing vaccines will be used globally either routinely or to mitigate/prevent epidemics. The proposed bivalent enteric fever vaccines (containing Typhoid and Paratyphoid components) will be indicated for vaccination of all ages including infants, and could replace typhoid only vaccines. Thus, a proper reference is important for the QC these vaccines and to compare products.


3-4 groups have publically disclosed intent to develop and manufacture bivalent enteric fever vaccines (which include a paratyphoid component).


At present, enteric fever is endemic in South and Southeast Asia. The disease is co-localized with typhoid. Typhoid and paratyphoid fevers are clinically indistinguishable.

Global importance

In 2008, the WHO estimated that > 27 m cases of enteric fever occurred annually. Case fatality rates of up to 5% have been reported, mostly in children less than 5 years of age. Incidence of Paratyphi A varies by region but in general ranges from 15-25% of all enteric fever cases. In a few areas incidence of > 50% has been reported.


Given the need for a Paratyphi A vaccine to control the disease there is a need for International Standards for O2 PS.

ECBS outcome

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Proposal (title) First International Standard for panel of O-antigen polysaccharides for Shigella strains



Rationale Multiple vaccine developers are pursing multivalent vaccines containing the immunodominant O-polysaccharide (PS) antigens of the most epidemiologically relevant serotypes of Shigella (eg, S. sonnei, S. flexneri 2a, 3a and 6). Several of these vaccines are already in clinical trials. Given the common target, the O-PS or repeating unit of LPS of many of these vaccines, global standards are needed for the quantification and testing of O-PS used in bioassays to measure the potency of these vaccines and to compare the immunogenicity of various vaccines.



Source/type of materials Purified O-antigen PS reflecting the most epidemiologically relevant serotypes of Shigella (eg, S. sonnei, S. flexneri 2a, 3a and 6) could be obtained from several sources including Walter Reed Army Institute of Research, Center for Vaccine Development - Univ Maryland Baltimore, Sclavo Behring Vaccine Institute for Global Health and PATH partners. This material would be of GMP standard. An assessment of freeze drying would need to be carried out by NIBSC prior to filling and this expertise is in-house.


The participants will be vaccine developers/manufactures and national control laboratories and is likely to be small. The CS will establish whether the material is ’fit for purpose’. The biochemical, biophysical characterization of 4 to 6 O- PSs will need to be aligned with the current literature as there is currently no TRS defining absolute requirements. Quantitative methods to determine the amount of O- PS, saccharide composition will be standard, and guidelines and pharmacopeias for injectable PS should be consulted. The use of this material can be either in immunoassays or for physicochemical methods. The study will assess the amount of O-PS per ampoule and provide the Uncertainty of Measurement (UoM) derived by combining a statistical analysis with assessments of systematic measurement bias.

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Working with not-for profit organizations will limit CoI.



Date proposed: May 2015



It is envisaged a multivalent Shigella vaccines will be used in sub-Saharan Africa and South Asia either routinely or to mitigate/prevent epidemics. The proposed vaccines will be indicated for vaccination of all ages including infants. Thus, a proper reference is important for the QC these vaccines and to compare between products.


Multiple Shigella vaccines have been publically disclosed to be under development using a variety of platforms (conjugate, subunit, attenuated oral and outer membrane). Monovalent vaccines for S. sonnei and S. flexneri 2a are also being developed.


Shigella serotypes are a major global cause of morbidity and mortality. Shigella flexneri and Shigella sonnei are responsible for > 125 million cases of moderate to sever diarrhea cases per year, mostly in children under 5 years of age in low and middle income countries. 90% of infections caused by Shigella occur in sub-Saharan Africa and South Asia. Travelers and deployed members of the military visiting endemic areas are also at risk for shigellosis.

Global importance

See public health importance.


Given the need for a vaccine to control Shigellosis there is a need for an International Standards for the O-PS of clinically relevant Shigella: S. sonnei, S. flexneri 2a, 3a and 6.

ECBS outcome

Documents

WHO/BS/2015.2272 ENGLISH ONLY EXPERT …...R1, 2011 performed consistently in the commercially available Vacczyme ELISA. In this ELISA, the GM potency of candidate IS 10/126 was calculated