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www.global-campaign.org
Rectal Microbicides:
New Hope for HIV and STD Prevention
www.global-campaign.org
• Why we need rectal microbicides
• What is involved in development
• Where the research is
• What you can do to get involved
Objectives
www.global-campaign.org
Men at risk
• High rates of condom use are difficult to maintain, as the rate of new HIV infections shows
• New data reveals reasons for concern:–UK: 48.8% UAI in the past year–US: 30% UAI (HIV - men in past year)
• STD rates confirm UAI prevalence
www.global-campaign.org
Women at risk
• In large US survey, 35% of women age 25-44 report having had anal sex at some time in their life
• 32% of high-risk women reported anal sex in past 6 months (Gross et al, 2000)
www.global-campaign.org
What is a microbicide?
Microbicides are substances that can reduce the transmission of HIV and other STD pathogens when applied vaginally and, possibly, rectally.
They are not yet available.
Currently, they are formulated as lubes, gels or creams applied with an applicator like those shown here
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We need a product that is…
• Inexpensive
• Easily accessible (over the counter)
• Easy to use
• Safe, non-irritating
• Available in various forms (in lubes, suppositories, on condoms)
• Effective
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What if we had a complete HIV toolkit?
Prior to exposure
Point of transmission
Treatment
•Male and female condoms and lube
•ART to prevent perinatal transmission
•Clean injecting equipment
•Vaginal and rectal microbicides
•Cervical barriers
•Post-exposure prophylaxis (PEP)
•Improved antiretroviral therapy
•Treatment for opportunistic infections
•Basic care/nutrition
•Prevention for positives
•Education and behavior change
•Therapeutic vaccines
•Rights-focused behaviour change
•Voluntary counselling and testing
•STI screening and treatment
•Male circumcision
•Preventative Vaccines
•Pre-exposure prophylaxis (PREP)
www.global-campaign.org
Why vaginal microbicides?• Women currently have no way to protect
themselves when her partner won’t use a condom
• Women biologically more vulnerable to HIV
– 2-4 times more likely than men to get HIV from vaginal sex
• Women may be less able to assert their rights
• Current methods (abstinence, fidelity, and condom use) often require male consent, knowledge, or cooperation
www.global-campaign.org
Laboratory Testing
2-6 Years
Phase 3(efficacy)
2 to 4 Years
Simultaneous studies in some cases:HIV+, penile & rectal safety
10 or more years
3 products3 products
4 products30+ products
Phase 1(safety)
1 to 6 Months
Phase 2(safety)
Up to 2 Years
25 – 40 people
200-400 people
3,000-10,000 people
Vaginal Microbicide Research in 2005
www.global-campaign.org
How could microbicides work?
• Kill/inactivate/immobilize the virus• Boost body’s natural defenses• Prohibit viral entry by blocking fusion• Inhibit viral replication• Create a physical barrier
or some combination of these approaches
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Physiological Differences
Vagina RectumMost of the
epithelium is 40 cell layers thick
Very fragile epithelium,1 cell layer thick.
Fewer CD4 cells than rectum
More inflammatory cells under surface
(CD4 receptors)
Acidic pH Alkaline, rather than acidic pH
Enclosed pouch Open-ended tube
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Anatomy 101
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Research questions
• Infection – more to learn about anal intercourse and HIV infection
• Testing - What assays (tests) to measure impact?
• Distribution – how would it spread?
• Application Methods?
• Dosing – how much, what is acceptable?
• How does rectal shedding of HIV impact risk?
www.global-campaign.org
Laboratory research
To learn more about:
• How HIV infection occurs in the rectum – what cells are most vulnerable
• The impact of intercourse on rectal tissue (trauma, inflammation, speed of healing)
• What markers can we look at to determine impact of a product on the rectum?
www.global-campaign.org
Laboratory research in action
Dr. Ian McGowan, HPTN 056University of California/Los Angeles
Goal: To define measurements that can be made on rectal tissue biopsies that would be of use in rectal microbicide safety studies.
Repeated measurements on 16 men, and studied variation based on:– Time– Location in the rectum– Sero status
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Penile Acceptability Studies
To learn more about…
• How much tissue is likely to be exposed to a microbicide
• Impact of a product on the penis
www.global-campaign.org
Distribution research in action:
Dr. Craig Hendrix at Johns Hopkins University in Baltimore
• Volunteers simulated anal intercourse
• MRI scans done up to five hours after its release
• Initial studies suggest that semen could travel up to 60 centimeters
• Showed where a microbicide would be needed to protect vulnerable tissues
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Behavioral Research
To learn more about…• Prevalence of anal intercourse for both
mean and women – and how many of these acts are protected
• Preferences re: formulation and delivery systems
• Sexual practices that affect microbicide feasibility
• How much product is acceptable
www.global-campaign.org
Behavioral research in action:
Alex Carballo-Diéguez, Columbia Univ (NY)Ken Mayer, Fenway Community Health (Boston)
How much gel is tolerable?• 18 HIV uninfected men• Maximum acceptable dose for insertion
and anal intercourse
www.global-campaign.org
Behavioral research in action:
Alex Carballo-Diéguez and Sigma Research Center both did surveys of MSM interest in
using microbicide
Results:In San Francisco: 59% heard of
microbicides, 25% - 35% might use (depending on stated effectiveness)
In the UK: 23% had heard of microbicides, 59% might use
www.global-campaign.org
More vital steps
1. Men and women need education about the risks of unprotected anal sex
2. Safety trials on rectal application of vaginal microbicides that are currently in large scale trials
3. Testing over the counter lubes to see how safe they are
4. Advocacy for increased research
www.global-campaign.org
Rectal safety trials on vaginal products
• We won’t know if the first vaginal microbicides are effective for rectal use
• But we must know if they are safe to put in the rectum or not
• Because some people will try to use them rectally
• If deemed harmful for the rectum, labels warning against rectal use are imperative.
www.global-campaign.org
Testing on over the counter
lubesDrs. Sudol & Phillips at Population Council, New
York
• Tested 5 OTC lubes in mice to see if they caused damage to rectal cells
• KY-Plus (no longer on market) and DeLube caused the most damage
• Viamore, Vagisil and Astroglide caused some damage
• More research is underway, with findings expected soon.
• Need more research to see if these products cause damage to human rectal cells
www.global-campaign.org
Online Lube Survey
• 7,500 participants from 100 countries• 700 women• Data analysis by UCLA• Information on condom and lubricant
use, rectal microbicide acceptability• Help establish priorities for testing
lubes for rectal safety
www.global-campaign.org
• Microbicide research is drastically under-funded
• Need for increased funding for both vaginal and rectal microbicides– Talk to your government officials– e.g., U.S. Microbicide Development Act
Advocacy for rectal microbicides
www.global-campaign.org
Global Campaign for Microbicides
A worldwide effort co-sponsored by groups working on• HIV/AIDS• reproductive health• gay health• women’s empowerment
Working to educate, raise awareness and generate collective advocacy for increased political and public investment in microbicide development
www.global-campaign.org
New strategy to raise awareness and demand among gay men
Three components:• Internet – http://lifelube.org• Public presence in forums &
conferences• Media – print, electronic, guerilla!
LifeLube.org
www.global-campaign.org
International Rectal Microbicides Working GroupWorking Collaboratively:• Global listserv• Bi-monthly conference calls• Developed an advocacy agenda• To join, contact Jim Pickett, [email protected]
Presence at conferences: – Microbicides 2006 conference– Gay Men’s Health Conferences– Gay and Lesbian Medical
Association annual meeting
www.global-campaign.org
What you can do
Visit www.global-campaign.org or www.irmwg.org to
• Join the International Rectal Microbicide Working Group calls and listserve
• Learn more about rectal microbicides• Sign up for the Global Campaign’s
newsletter• Host a talk on microbicides – this and other
presentations available for download• Endorse the Global Campaign