On May 18, 1997, then US president Bill Clinton committed to developing an Aids vaccine within 10 years. Nearly 20 years later, we still don't have one. And every day in Thailand, 22 people become newly infected, the great majority of whom are under age 25.
But Aids vaccine advocates do have a lot to celebrate in the field of Aids vaccines, and HIV prevention generally. For much of the first 30 years of the epidemic, there has been essentially two strategies to prevent sexual transmission of HIV: abstinence and condoms. But in the past decade, we've had important advances.
For example, we now know that anti-HIV drugs not only keep HIV positive people healthy, they work so well that a person on successful HIV treatment has very little chance of passing the virus to a sexual partner. Treatment is also prevention.
Multiple studies - some of them here in Thailand - have shown that people at risk of HIV can take a particular anti-HIV medication to prevent infection when they take the pills consistently, in a strategy called PrEP, or pre-exposure prophylaxis. We need to make sure that all of the HIV prevention methods we have today reach the people who need them.
At the same time we need to continue the investments in research to ensure even more prevention options are developed and made available. An Aids vaccine remains essential to ultimately ending the epidemic.
Happily, today on HIV Vaccine Awareness Day 2015, we can report progress.
In 2009, a clinical trial here in Thailand, in which more than 16,000 Thai men and women participated, showed for the first time that an experimental vaccine modestly reduced the risk of HIV transmission. Since that time, scientists in Thailand and around the world have made great progress in understanding how that vaccine worked, and how to make it better. And early this year, a trial to test a modified version of that vaccine - hopefully making it more protective - started in South Africa.
If this trial finds positive results, in two years a large-scale efficacy trial would begin, which could eventually lead to a licensed vaccine. We also look forward to additional trials of this vaccine strategy here in Thailand.
This year we will also see a significant step by industry: Janssen, part of Johnson & Johnson, is launching its own international clinical trial to test a vaccine developed with partners. We haven't seen a large vaccine developer invest in clinical trials for Aids vaccine without public or charitable contributions in almost a decade. This vaccine strategy incorporates a strategy that researchers hope will protect against the many different types of HIV that circulate around the world.
Further upstream research involves the discovery that some people living with HIV create particularly potent antibodies that are able to neutralise many different HIV strains. A handful of these "broadly neutralising antibodies", or bNAbs, have been isolated from blood samples donated by HIV-infected individuals. Scientists are now planning to test whether direct transfer of the most potent antibodies could prevent, treat, or even be part of a cure for HIV when infused directly into the blood stream.
With all of the excitement around bNAbs, and different vaccine strategies now entering clinical trial phases in Africa and around the globe, the robust community of global Aids researchers must be at the table before decisions are made. HIV activists, advocates and community stakeholders who will need to explain the science, purpose and possible outcomes of this research need support to track the research path, ask the hard questions, demand progress and efficiency, and other aspects of the R&D process.
We are closer than ever to having an Aids vaccine. But funding is finite; researchers and decision-makers need to direct efforts toward only the likeliest candidates for success. And the decision-making process must include the people who really need an Aids vaccine.
Udom Likhitwonnawut is a vaccine and HIV-prevention advocate.