CDC-Funded Clinical Trial Testing Tenofovir for HIV Prevention To Begin Next Month in Bangkok
A CDC-funded, three-year clinical trial testing Gilead's antiretroviral drug Viread to determine its effectiveness in preventing HIV transmission is scheduled to begin next month in Bangkok, Thailand, the Bangkok Post reports (Wancharoen, Bangkok Post, 3/8). The drug, which is known generically as tenofovir, works by blocking HIV's reverse transcriptase enzyme to prevent replication. Tenofovir is FDA-approved for use as a treatment for HIV infection and has been shown to boost immune response and lower viral levels in the bloodstreams of patients who are resistant to other antiretrovirals (Kaiser Daily HIV/AIDS Report, 2/7). The trial, which has been approved by Thailand's Ministry of Public Health, will be conducted in the city by the Bangkok Metropolitan Administration at Taskin Hospital, BMA Deputy City Clerk Pitinan Natrujirote said. About 1,600 volunteers, including injection drug users and other people at high risk of contracting HIV, will be recruited to participate in the trial, Pitinan said (Bangkok Post, 3/8). CDC also has awarded $3.5 million in grants to fund trials of Viread in San Francisco and Atlanta.
NIH and the Bill & Melinda Gates Foundation also are funding studies of Viread (Kaiser Daily HIV/AIDS Report, 2/7). NIH in March 2004 awarded a $2.1 million grant to University of California-San Francisco researchers to test Viread in 960 Cambodian women, most of whom were commercial sex workers. However, Cambodian Prime Minister Hun Sen in August 2004 ordered an end to the planned trial -- which is funded in part by the Gates Foundation -- because of the possible effects of the drug on trial participants. Previously, about 150 Cambodian commercial sex workers who are members of the Women's Network for Unity had said they would not participate in the study unless they were provided with 30 years of health insurance to cover possible adverse reactions and side effects from taking the drug (Kaiser Daily HIV/AIDS Report, 8/12/04).
The Gates Foundation also awarded a $6.5 million grant to Family Health International to conduct a randomized, placebo-controlled clinical trial of Viread including 2,000 HIV-negative volunteers at sites in Cambodia, Ghana, Cameroon, Nigeria and Malawi (Kaiser Daily HIV/AIDS Report, 2/7). However, Cameroon's Ministry of Health last month announced that it had suspended the trial, which involved HIV-negative commercial sex workers in the city of Douala, after the advocacy group ACT UP/Paris alleged that the trial violated ethical norms and called for it to be stopped. ACT UP/Paris claims that the study recruited particularly vulnerable participants without providing HIV/AIDS prevention information or treatment. However, Dr. Ward Cates, president of FHI's Institute for Family Health, denied ACT UP/Paris' claim that the study is unethical. FHI said it is addressing all of the ministry's concerns and is making progress in implementing its recommendations, including revisions to administrative procedures and augmenting local partnerships with HIV/AIDS prevention and control organizations to provide better counseling and support for trial participants. The health ministry has agreed to allow the follow-up of participants currently enrolled in the trial (Kaiser Daily HIV/AIDS Report, 2/24).