The Conference on Retroviruses and Opportunistic Infections (CROI) is one of the biggest events on the HIV related calendar, providing a narrower focus on ‘basic science’ (as opposed to “social science”) than the few even larger events, such as the conference of the International AIDS society.
At CROI 2011, which straddled the February-March transition in Boston, I asked a number of people what they thought were the really hot topics or results. Underlying some diversity of views, it was perhaps ‘Pre-Exposure Prophylaxis’ (PrEP) which came up the most frequently. An entire session was dedicated to the topic, and within that, most of the presentations were ‘late breaking’ subsidiary analyses to the ‘Preexposure Chemoprophylaxis for HIV Prevention in Men Who Have Sex with Men’ study which had just published its primary findings in the New England Journal of Medicine. This is a hotly anticipated article, many years in the making, which reported strong evidence that a daily oral dose of Tenofovir provides significant reduction in the ‘per-exposure’ risk of HIV acquisition (1).
The 95% confidence interval of the risk reduction was reported as (15-63%) in an ‘intention-to-treat analysis’ – meaning a conservative view in which non-adherence to the regimen (which presumably weakens the study’s ability to see the effect) was disregarded. Subsidiary analysis found lower infection rates in individuals with detectable levels of drug, suggesting that the effect on people who are actually properly dosed, is better than observed at the level of averaging over the group. It did not appear that there was significant increase in other risk factors correlated to taking a daily regimen.
Nevertheless, deep questions remain about how this strategy, which, let’s spell it out – provides antiretroviral treatment to HIV negative people – really fits into a world in which the majority of HIV infected persons lack access to treatment.
On the matter of access to treatment – it was interesting to see that, while a few years ago it was quite controversial to propose offering treatment to anyone found to be HIV positive, there are now several locales and study contexts in which this is routine. What is now mainstream where there are sufficient resources per (HIV positive) capita is, however, still a controversial idea in the regions where most HIV positive people live – such as right here in South Africa.
Some other highlights of CROI included an excellent study on self-test kits in Malawi (a potentially crucial step towards expanding access to early testing and treatment in under-resourced settings), reviews of ART fifteen years on (an interesting stage in the maturation of a new kind of treatment that is here to stay for a long time) a strong session on prevention of mother to child transmission (the only truly successful ‘prevention’ program – and a potential model for adult to adult transmission prevention in its use of ARVs) and the usual vibrant poster session – which sees over a thousand posters displayed for 4 days amidst vigorous discussion and exchange of views and contact details. The CROI website provides excellent access to presentations, including complete footage of oral sessions. Although HIV/AIDS dominates the agenda in local epidemiology, SACEMA is not an HIV research organization, and we are pleased to present three articles on very different topics. Bruce Biccard writes for us on perioperative cardiovascular disease – something one hopes we can also afford to pay attention to in South Africa against the backdrop of rampant infectious disease. Steve Bellan provides a methodological perspective involving carcass surveillance, and we provide the reader with our two Bobs’ worth (Bob Dransfield and Bob Brightwell) on how medical research can fail so impressively. We trust you will find something of interest in this edition of the SACEMA epidemiological quarterly.