Rectal Microbicides: New Hope for HIV and STD Prevention www. global-campaign. org
Objectives • • Why we need rectal microbicides What is involved in development Where the research is What you can do to get involved 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 www. global-campaign. org
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 www. global-campaign. org
What if we had a complete HIV toolkit? Prior to exposure Point of transmission Treatment • Rights-focused behaviour change • Male and female condoms and lube • Improved antiretroviral therapy • Voluntary counselling and testing • ART to prevent perinatal transmission • Treatment for opportunistic infections • STI screening and treatment • Preventative Vaccines • Pre-exposure prophylaxis (PREP) • Male circumcision • Clean injecting equipment • Basic care/nutrition • Vaginal and rectal microbicides • Prevention for positives • Cervical barriers • Education and behavior change • Post-exposure prophylaxis (PEP) • Therapeutic vaccines 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
Vaginal Microbicide Research in 2005 10 -20 products Laboratory Testing 2 -6 Years 6 products 3 products 5 products Phase 1 (safety) Phase 2 (safety) Phase 3 (efficacy) 1 to 6 Months Up to 2 Years 2 to 4 Years 25 – 40 people 200 -400 people 3, 000 -10, 000 people Simultaneous studies in some cases: HIV+, penile & rectal safety 10 or more years 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 www. global-campaign. org
Physiological Differences Vagina Rectum Most of the epithelium is 40 cell layers thick Very fragile epithelium, 1 cell layer thick. Fewer CD 4 cells than rectum More inflammatory cells under surface (CD 4 receptors) Acidic p. H Alkaline, rather than acidic p. H Enclosed pouch Open-ended tube www. global-campaign. org
Anatomy 101 www. global-campaign. org
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 Mc. Gowan, HPTN 056 University 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 www. global-campaign. org
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 www. global-campaign. org
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 lubes Drs. 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 De. Lube 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
Advocacy for rectal microbicides • Microbicide research is drastically underfunded • Need for increased funding for both vaginal and rectal microbicides – Talk to your government officials – e. g. , U. S. Microbicide Development Act 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
Life. Lube. 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! www. global-campaign. org
International Rectal Microbicides Working Group Working Collaboratively: • Global listserv • Bi-monthly conference calls • Developed an advocacy agenda • To join, contact Jim Pickett, jpickett@aidschicago. org 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. lifelube. 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 www. global-campaign. org
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