Rectal microbicide research gives hope for HIV protection

According to the Microbicides Trials Network (MTN), HIV continues to disproportionately affect racial minorities and men who have sex with men (MSM). MTN estimates that 5 to 10 percent of the world’s population engages in anal sex and globally, MSM are 19 times more likely to be infected with HIV than the general population. Unprotected anal sex is the primary driver of the HIV epidemic among this population. The risk of becoming infected with HIV during unprotected anal sex is 10 to 20 times greater than unprotected vaginal sex, because the rectal lining being only one-cell thick, it allows the virus to easily reach immune cells to infect.  

Rectal Microbicides are products in the form of gels or lubricants which, when applied inside the rectum, would reduce a person’s risk of HIV or other sexually transmitted infections from anal sex. They are still in the development and testing stage. If proven effective, rectal microbicides could protect against HIV in people who are unable or reluctant to use condoms. When available, they  appear to be a tool that can have a profound role in protecting HIV transmission in all those having anal intercourse, whether they be heterosexuals or MSMs. 

“Rectal microbicides are critical to turn the tide of the AIDS pandemic as we know that unprotected anal intercourse is the riskiest of HIV related behaviours. Human beings, all over the world, regardless of gender and sexuality, have anal intercourse and a lot of this is unprotected because they do not have access to condoms and/or because of the mistaken notion that anal intercourse is safer than vaginal intercourse with regards to contracting HIV. Having more tools for protection, in addition to what we already have, I think would be absolutely critical,” says Jim Pickett, Director (Advocacy), Chicago AIDS Foundation and founder-chair of International Rectal Microbicide Advocates (IRMA).

Photo credit: Aliwassa Thanachaikan-CNS 
In an update on the CHARM (Combination HIV Antiretroviral Rectal Microbicide) Program, Dr Ian McGowan, Professor of Medicine, University of Pittsburgh, and Co-principal Investigator MTN, informs that, “Microbicides are products that can be applied to the vaginal or rectal mucosa with the intent of preventing or significantly reducing the risk of acquiring Sexually Transmitted Infections including HIV. Combination antiretrovirals are more potent and more useful as rectal microbicides. The rationale behind the CHARM programme is that we need a rectal specific combination antiretroviral microbicide.” Likewise, Anna Forbes, Omololu Falobi Awardee for 2012, and a women rights’ activist, advocates that, “A rectal microbicide would be useful for a woman who is having anal sex. We certainly know that both men and women have anal sex. What we do not know is the effect it will have because they are still in the early research trials but certainly women are going to need both vaginal and rectal microbicides.”

Rectal microbicides are moving forward in the research pipeline. Jim Pickett is rightly excited about the launch of the first phase-II trial of a rectal microbicide, after having completed 3 phase-I studies in small groups. He informs, “The very first phase-II clinical trial of a rectal microbicide product is going to start this year on 186 MSMs and transgender women recruited in 4 countries: Thailand, South Africa, United States and Peru. This safety and acceptability trial will test a reduced glycerine formulation of the tenofovir gel. This is like taking a quantum leap forward. If this is successful the next step would be to move forward to a phase-IIB or phase-III trial which will involve many more people over a longer duration of time and will be able to answer the question whether the product is effective or not with respect to HIV. So I think in an ideal world we may hope to see a product by 2018 or 2020.”

However, the mere availability of a product in the market does not ensure its effective use. Healthcare professionals will have to be informed and educated with a view to popularize it too. Jim elaborates, “As we move forward with rectal microbicide research, we need to do more work around understanding anal intercourse globally. There are still many people who think that this is an issue only for MSMs and there is still denial that heterosexuals indulge in anal intercourse. There is still a lot of stigma around this behaviour. Hence along with developing products we must work to de-stigmatise this behaviour and educate and inform people to dissuade them from the very incorrect and deadly assumptions they harbour. As in many parts of the world HIV prevention messaging has been focussed on heterosexuals, there are people who think to have anal sex to protect from HIV infection because of the notion that unprotected vaginal intercourse is the chief cause of the HIV infection. Then there are gay men who have never found any protection messaging directed towards them. They have been ignored and they have not been prioritised. In many places same sex behaviour is criminalised, with no prevention messages or services directed to them. So they take home the message that the HIV pandemic does not apply to them but only to heterosexuals. These assumptions lead people to make wrong decisions about their sex life putting them to extraordinary risk of a devastating illness.”

Added Jim: “There are other concerns surrounding safety of anal intercourse too. We know that people who have anal intercourse should use a safe condom compatible lubricant. Unfortunately condom compatible lubricants are not widely available for many people around the world. So, people are forced to use lubricants which hurt or prick the condoms thus preventing them from providing protection. Thus lubricant access is a huge issue. There are plenty of prevention programmes that distribute free condoms but they do not distribute lubricants, which is not correct. Condoms must be used with lubricants especially for anal intercourse. For vaginal intercourse it is different, as the vagina lubricates itself. There are women who need extra lubrication and when having vaginal intercourse must use condom along with a condom compatible lubricant. We are really interested in throwing light on this and pushing governments, national health programmes, and HIV prevention programmes to include condom compatible lube (lubricant) in their service delivery. If they are handing out condoms a condom should always be used with a lube.” 

This is the key message which International Rectal Microbicide Advocates (IRMA) will be carrying throughout the XIX International AIDS Conference (AIDS 2012) being held later this month in Washington DC. IRMA will launch its Global Lube Access Mobilization (GLAM) campaign which, though focussed on Africa, will have global implications because there is lube access issue all over the world. In accordance with the theme of the XIX International AIDS conference, ‘Turning the tide together’, let us hope that in the coming few years as rectal microbicides research goes ahead, we will have a safe and effective rectal microbicide available for use by men and women in order to contribute to turning this indomitable tide.

Somya Arora - CNS