Gilead Reluctant To Promote Antiretroviral Truvada as Method of HIV Prevention
Foster City, Calif.-based Gilead is trying to curb the anticipation surrounding the potential of its antiretroviral drug Truvada to prevent HIV transmission after a CDC study presented last month showed positive signs of the drug's preventive effects in monkeys, the AP/San Jose Mercury News reports (Elias, AP/San Jose Mercury News, 3/29). CDC researcher Walid Heneine last month at the Conference on Retroviruses and Opportunistic Infections in Denver presented a study that showed that six rhesus macaques that were given Truvada -- which contains Viread, also known as tenofovir, and Emtriva, or emtracitibine -- did not contract simian HIV despite being exposed to the virus daily for 14 days (Kaiser Daily HIV/AIDS Report, 2/8). In contrast, five of six macaques in the study who did not receive Truvada contracted SHIV (Garcia-Lerma et al., CROI oral abstract, 2/6). "It's premature to speculate on what the actual use of [Truvada] might be at this time," Gilead Medical Affairs Vice President James Rooney said, adding, "We really need data from clinical trials to determine what the effectiveness of the pill would be as a preventive." Some analysts say that if Truvada is used "off-label" as a prophylactic and then proven ineffective at preventing HIV transmission, there might be backlash against Gilead, the AP/Mercury News reports (AP/San Jose Mercury News, 3/29).
Human Trials of Truvada, Tenofovir
CDC last year approved $19 million in funding for clinical trials testing tenofovir as a preventive among men who have sex with men in Atlanta and San Francisco, injection drug users in Thailand, and men and women in Botswana, the AP/Houston Chronicle reports (Marchione, AP/Houston Chronicle, 3/27). Researchers in the U.S. plan to enroll 200 MSM in a double-blind study in which participants will be assigned to take the drug or a placebo every day for two years (Kaiser Daily HIV/AIDS Report, 3/6). The agency last week said it will add one U.S. city to the tenofovir studies, and the drug studied in the Botswana trial will be switched from tenofovir to Truvada because of the macaque trial, according to the AP/Chronicle. NIH also recently announced it is funding a study of tenofovir among 1,400 MSM in Peru, and other studies are being considered (AP/Houston Chronicle, 3/27).