IAVI REPORT – VOL. 15, NO. 6, 2011
In 2011, the year marking the 30th anniversary of AIDS, HIV prevention researchers had cause to reflect, and to celebrate. First came news in May from the landmark HPTN 052 trial, showing that earlier administration of antiretroviral (ARV) therapy to the HIV-infected partners in serodiscordant couples could reduce HIV transmission by 96%. Then, just before this year’s International AIDS Conference, results from two trials of pre-exposure prophylaxis (PrEP; the administration of ARVs to uninfected individuals) showed this strategy was 62%-73% effective at preventing HIV infection.
The results from these three studies inspired optimism and may lead to new policy recommendations or guidelines on the use of ARVs to treat HIV infection earlier or prevent it from occurring altogether.
However, with regards to PrEP, the story is far from over. Since the results of these two trials were released, investigators conducting a large, multi-site, efficacy trial known as VOICE, involving approximately 5,000 women, have announced the discontinuation of the arm testing the ARV-based microbicide gel (which was shown to reduce HIV infection rates in the CAPRISA 004 trial by 39%) and the one-drug PrEP arm of the trial, both for futility. Now, only the two-drug oral PrEP arm is continuing. Although the analysis of adherence and other factors will be critical to understanding these results, they have nonetheless raised questions about how well PrEP may work in different populations.
In vaccine research, the biggest news of the year came from the correlates analysis of the RV144 trial in Thailand, the first to show any efficacy (see A Bangkok Surprise, IAVI Report, Sep.-Oct. 2011). In addition to that, there continues to be incremental progress in elucidating the epitopes targeted by the dozens of broadly neutralizing antibodies researchers have amassed in the past few years (see Vaccine Briefs), and in extracting information from nonhuman primate models of HIV/AIDS (see More Monkey Business).
In this issue, we also feature an update from the Keystone Symposium on Malnutrition, Gut-Microbial Interactions and Mucosal Immunity, the first Keystone meeting in India, at which researchers discussed the link between nutrition, gut health, and the immune response to vaccines (see A Gut Response to Vaccines).
While 2011 was certainly eventful, there is still much work to do. The number of new HIV infections last year plateaued, and there were impressive declines in HIV incidence in several sub-Saharan African countries, but at the same time there was a marked increase in infection rates in other parts of the world (see Vaccine Briefs). Progress is afoot, but the science, funding, and commitment to HIV/AIDS prevention remain as important as ever.
—Kristen Jill Kresge, Managing Editor