In January, Science reported that a number of top AIDS researchers in the United States say the world's biggest HIV vaccine trials, taking place in Thailand, are a "costly mistake". The protein in the vaccine has, they say, been proven to be incapable of preventing infection (see World's biggest HIV vaccine trial 'is a costly mistake')

In this letter, Charal Trinvuthipong, head of disease control in Thailand's Ministry of Public Health, says the US researchers mention only one vaccine, while the Thai trials are studying two using a 'prime-boost' strategy — one vaccine as primer, one as booster. Moreover, a special consultation by the World Health Organisation (WHO), the Joint United Nations Programme on HIV/AIDS (UNAIDS) and the US Centers for Disease Control deemed it appropriate to go ahead with the study. And finally, protocols for the study were endorsed not only by institutional review boards and expert committees in Thailand and the United States, but also by the WHO and UNAIDS.

Trinvuthipong stresses that whatever the outcome, experience will be gained by both scientists and health workers, the laboratory infrastructure will be strengthened, and community awareness of the issues raised.

Link to full letter in Science

Reference: Science 303, 954 (2004)