First HIV vaccine trial success confirmed

The first HIV vaccine to be called a success has stood up to scrutiny after further analysis of the data was presented today in Paris, France.

However, the new analysis also confirms that the optimistic claims, first made in September and viewed sceptically at the time, are indeed very modest.

Last month's announcement of success (PDF) was made by researchers from the US Military HIV Research Program (MHRP). They reported that their vaccine reduced the risk of infection by about 31 per cent in a trial in Thailand.

But it was not clear that the vaccine offered any protection because the result was based on very few cases: 51 of 8197 vaccinated individuals became infected with HIV compared with 74 of 8198 unvaccinated people, a difference of just 23.