The National Institutes of Health, the Bill and Melinda Gates Foundation, and the Centers for Disease Control and Prevention this week announced funding of three separate human trials of the antiretroviral drug Viread to prevent HIV infections, The Wall Street Journal reports. The drug, approved for use as part of combination therapy to treat HIV infection, has been shown in early tests to prevent HIV infection when taken regularly as pre-exposure prophylaxis. The human trials will include studies of sexually active gay and bisexual men in San Francisco and Atlanta, sex workers in Cambodia, and HIV-negative volunteers in four African nations. The Gates Foundation has provided $6.5 million for the African study, the NIH is supporting the Cambodian trial with a $2.1 million grant, and the study of sexually active gay men is funded by a $3.5 million CDC grant.
Some at-risk people are already taking the anti-HIV drug to help prevent HIV infection, the Journal reports, which draws both support and caution from physicians. "I believe in being ahead of the curve. But if we're wrong, the results could be devastating," said Howard Grossman, a New York AIDS specialist. Viread has such side effects as kidney and bone toxicity. But health experts also worry that those currently taking the anti-HIV medication to prevent infection could stop using condoms or increase their sexual risk-taking because they believe the medication will shield them from HIV infection, which has not yet been proven. Officials at Gilead Sciences, the maker of Viread, are optimistic that the trials will show that the medication lowers the chances of HIV infection and plan to examine ways to boost production of the drug to handle the "tremendous number of people who would require Viread," said company vice president of clinical research James Rooney.