Taking antiviral drug ‘on demand’ guards against HIV

For preventing HIV infection, a daily pill may be overkill.

Instead, an antiretroviral drug taken before and after sex could get the job done, researchers report December 1 in the New England Journal of Medicine. The treatment plan might be easier for patients, too.

Scientists have previously suggested that a daily dose of antiretroviral drugs guards against HIV infection, but results have been mixed. That’s probably because study participants have a hard time sticking to the regimen, writes Jean-Michel Molina of Hôpital Saint-Louis in Paris and colleagues.

So they instructed 199 men at high risk of contracting HIV to take a drug called Truvada two to 24 hours before sex, and then again 24 and 48 hours afterwards. The men were 86 percent less likely to acquire HIV compared with 201 men who took a placebo, the researchers found.