Following the failure last year of a vaccine candidate developed by the pharmaceutical company Merck, and tested here in South Africa in the Phambili trial and in other countries around the world in the STEP trial, we observe the date this year with disappointment, but also with resolve.
There is simple, clear message that must be heard on this day’and every day’that an AIDS vaccine is possible. And it is critically needed!
Eleven years ago, when US President Clinton called for an accelerated effort to develop an AIDS vaccine, the field was reeling from the failure of early vaccine candidates and grappling with the complexities of the task of developing an effective vaccine. At that time no AIDS vaccine trials had been conducted here in South Africa, and few trials had been conducted outside of the U.S.
Today, there is a robust global AIDS vaccine research and development agenda and researchers here in South Africa and elsewhere on the continent are a major part of the research effort. Thousands of men and women in South Africa and around the world have volunteered for AIDS vaccine trials that have provided critical information for researchers to help move the field forward. And, despite the recent setbacks, most scientists still believe that a vaccine is possible and many volunteers remain committed to testing candidate AIDS vaccines.
Discovering and developing an AIDS vaccine will be especially difficult. It must be a global effort with dedicated work from hundreds, or even thousands, of researchers and the participation of tens of thousands of men and women volunteering for clinical trials in South Africa and around the world, and it will require the cooperation of governments and policymakers, funders, and community leaders.
All of this is made more urgent following the disappointing results of the vaccine being tested in the Phambili and STEP trials and by the news that the vaccine may have caused some volunteers to be more susceptible to HIV infection, for reasons researchers are continuing to investigate.
But we cannot give up. The lives of millions of people here and around the world depend on our finding more options for preventing HIV infection.
Some have called for vaccine research to retreat to the lab and go back to basics. But this is not the answer. The AIDS vaccine effort has always included basic science, preclinical work and human trials and must continue to integrate all of these components going forward. The results of the STEP trial could not have been predicted from studies in the laboratory or in animals and that is why it is important that research in all areas continues.
The outcome of clinical trials of one candidate vaccine, no matter how disappointing, cannot form the basis for abandoning human testing of AIDS vaccine candidates. Human clinical trials are absolutely critical for gathering much-needed information to move research forward. If researchers gave up on developing drugs or vaccines because of unsuccessful attempts, we would have far fewer treatment and prevention options for many diseases. For instance, we would not have a polio vaccine or drugs to treat TB.
There is no doubt that we are closer to finding an AIDS vaccine now than we were a decade ago, and we must continue to go forward, building on sound science’including what we have learned from the Phambili and STEP trials.
Fortunately, the last decade has also brought new treatments for HIV infection and an unprecedented global effort to ensure that more people have access to HIV treatment and existing prevention options, including male and female condoms.
And there are now more research efforts underway to find new biomedical prevention interventions, including microbicides and other interventions that could be controlled by women. A clinical trial here in South Africa showed that male circumcision reduces HIV infection rates and work is underway to make this intervention available to men in many communities.
We are adamant that that the search for an AIDS vaccine must emphasize perseverance, but must also simultaneously redouble efforts to implement proven prevention and treatment efforts and to identify other new biomedical prevention strategies.
The AIDS vaccine field has been disappointed, discouraged and’in all honesty’uncertain what the next ten or twenty years will hold for AIDS vaccine research. But that is the nature of the scientific process. Every field that has had breakthroughs has also had setbacks. And we need to anticipate more setbacks in our search for an AIDS vaccine.
To acknowledge failure of a single vaccine candidate is in no way to concede overall defeat. We all now have a tremendous opportunity to learn from these disappointments and to be better for them’better, even, than we might have been without them.
Mitchell Warren is the executive director of the AIDS Vaccine Advocacy Coalition (AVAC) based in New York. Lynn Morris is the Head of the AIDS Unit at the National Institute for Communicable Diseases (NICD) based in Johannesburg, and the Chair of the AIDS Vaccine 2008 Conference that will be held in Cape Town in October.