This morning I woke up to news I have been waiting to hear for more than 20 years. Researchers have finally developed a preventive vaccine against HIV that showed modest efficacy. For every 100 people that would have become infected if they had not received the vaccine, 32 infections were prevented. This level of efficacy (32%) is modest, and too low to proceed to license the vaccine. However, the results are significant. They will give a real boost to the field and provide a base on which they can improve.
While this is absolutely reason to celebrate a remarkable scientific achievement, we should note a couple of important things:
First, the vaccine was only studied with the type of HIV commonly found in Thailand. More research will have to be done to discover whether similar results can be shown in Africa and North and South American strains.
Second, researchers also wanted to discover if the vaccine had any effect on reducing the amount of virus in the blood of volunteers who seroconverted during the trial. Sadly, it did not have any therapeutic benefits.
Still, this is a clear victory that gives researchers, and all of us who care about ending AIDS, one thing that has been in short supply: hope that we will be the generation that ends AIDS through the discovery of a preventive vaccine.