First HIV drug approved as prevention

US regulators have for the first time approved a drug to be used to prevent HIV infection – as opposed to treating it. Truvada (emtricitabine, tenofovir) tablets, which combine two antiretroviral agents, were approved in the US for treating patients infected with HIV in 2004. But there is evidence that an uninfected individual can reduce his or her risk of acquiring the virus by taking the medication.

One clinical trial involved 2500 HIV-negative men or transgender women having sex with men and engaging in behaviour that put them at high risk of infection. Truvada tablets reduced the risk of HIV infection by 42% compared with placebo – and instances of the medication being less effective correlated with failure to stick to the drug regimen. Another trial involved 4800 heterosexual couples comprising one HIV-positive person and one HIV-negative person. In it, Truvada tablets reduced the risk of becoming infected by 75% compared with placebo.

According to estimates, 1.2 million people in the US are living with HIV infection, and despite the availability of preventative products, such as condoms, the incidence rate has changed little over the past 20 years: 50,000 new infections occur each year.

In a sad coincidence, renowned Czech chemist Antonín Holý died on same day (16 July) as the announcement about the Truvada brand. Tenofovir was one of several antiretroviral agents that came out of a highly fruitful partnership between Holý, at the Academy of Sciences of the Czech Republic (IOCB) in Prague, and Belgian virologist Erik DeClercq, at the Rega Institute for Medical Research in Belgium. Holý was 75 at his death.