After CAPRISA, it’s not exactly rainbows and lollipops, as there is much to be done to confirm and extend these findings and then actually make this drug available, accessible.
naysayers were not exactly gleeful—how can one be happy, after all, about these dead ends in prevention research? But I’d say there was a lot of smug to go around. Finally we have a win. I must say I was feeling a little smug myself when several folks approached me at the conference to say variations of “I never quite understood why you were so passionate about microbicides… I thought you were a little nuts... You must feel vindicated…” Lots of us feel vindicated, thank you very much. After CAPRISA, it’s not exactly rainbows and lollipops, as there is much to be done to confirm and extend these findings and then actually make this drug available, accessible. One study that is currently underway in a number of African countries will be able to confirm whether tenofovir gel works or not. While the 5,000 women in the VOICE trial are using a different dosing regimen than the CAPRISA participants, the data will be very important. Other studies are being planned to follow up on CAPRISA. Obtaining the necessary resources for such trials is the current—big—challenge. But what do these new findings mean for rectal microbicides? “The positive results from the CAPRISA study represent a very significant milestone in HIV prevention research and they increase optimism that we can develop safe and effective antiretroviral rectal microbicides,” said University of Pittsburgh’s Dr. Ian McGowan, International Rectal Microbicide Advocates (IRMA) Scientific Vice-Chair and co-principal investigator of the Microbicide Trials Network. “Phase 1 rectal safety studies with tenofovir are ongoing and these efforts need to be intensified to help us move forward to rectal microbicide effectiveness studies as quickly as possible,” he said. Anal intercourse is a common human sexual behavior, practiced by approximately P os i t i velyAwa re.com
5-10% of the world’s general population, including heterosexual women and men, gay men, and other MSM. Because an act of unprotected anal intercourse is 10 to 20 times more likely to result in HIV transmission compared to unprotected vaginal intercourse, it is likely that unprotected anal intercourse is a significant driver in the HIV epidemic overall. We know that unprotected anal intercourse is the chief cause of HIV infection for gay men/MSM across the world. But gay men are under-represented in most national AIDS strategies, in epidemiology, surveillance, and in research—if they show up at all. They have been woefully underserved by prevention, care, treatment, and support services. Similarly, we have inadequate data regarding anal intercourse—homosexual and heterosexual—due to politics, stigma, criminalization, and outright denial. It’s hard to study a behavior that’s against the law in some places. Globally, gay men/MSM are 19 times more likely to be HIV-positive compared to the general population. These disproportionate rates extend to Africa, where the epidemic is often characterized as “heterosexual.” For instance, according to data from Dr. Chris Beyrer presented at the Global Forum on MSM and HIV’s “Be Heard!” pre-conference on July 17, in Kenya, 15.2% of gay/MSM are HIV-positive compared to 6.1% of the general population; in Uganda, HIV prevalence rates among gay men/MSM are just above 40% compared to 5% for other Ugandan men of reproductive age. Data released by the U.S. Centers for Disease Control and Prevention (CDC) in early 2010 revealed that gay men/MSM in the United States are 44 times more likely to be HIV-positive than other men, and 40 times more likely to be HIV-positive than women. The bottom line is that for the men and women who engage in anal intercourse,
condoms work quite well to prevent HIV, but many people do not use them, or are simply unable to use them due to a number of issues, including power dynamics in sexual relationships, stigma, and a serious lack of availability. According to the Global HIV Prevention Working Group, only 9% of individuals at risk for HIV infection had access to male condoms in 2008. Condom-compatible lubricants are also in dangerously short supply, especially in Africa. We need to do much better with what we have available now, and we should be pushing female condoms more than we are, especially since a new model has come out that has proven to be much more acceptable to women and men, and can be used for anal intercourse as well. While the rectal microbicide field has gained significant momentum, more focus and resources are necessary. In 2010, 7.2 million U.S. dollars are being spent globally on rectal microbicide research. IRMA has calculated that annual investments must increase by 40% from 2011-2014, to $10 million per year and must increase further to $44 million in the years 20152020 to ensure a minimum of candidate products are moving through the research pipeline into late stage testing for effectiveness. Advocates are optimistic that the CAPRISA proof of concept will also be translated into more financial and creative energy being put into rectal microbicide development. With five new infections for every two individuals beginning treatment, it’s absolutely imperative we find new ways to prevent HIV for individuals at risk, gay and straight, women and men. As these new methods become available, it is also of paramount importance that people who are already using condoms correctly and consistently continue doing so. We won’t treat our way out of this global epidemic. As of this writing, over 3,400 individuals in the U.S. bide their N ov e m b e r / D e c e m b e r 2 01 0 |
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