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It Will Take a Village
By Michael Schwarz, Producer, ENDING AIDS

The search for an AIDS vaccine will ultimately rely not just on the creativity and inventiveness of scientists, but also on the willingness of tens of thousands of people to volunteer for the various trials that will be required before any vaccine can be proved effective.

The vaccine trial process is arduous and time-consuming. Before being made available to the general public, any vaccine must go through a three-phase clinical trial process. The first phase is designed to make sure that the vaccine is safe and does no harm. The second phase assesses vaccine safety among a larger group and also evaluates the immune responses it triggers. And the final phase, the "efficacy" trial, is a real-world test involving thousands of people—some of whom get the vaccine, while others get a placebo or dummy vaccine—to determine whether the vaccine works. From beginning to end, this process typically takes 7 to 12 years and can cost several hundred million dollars.

One of the chief concerns of the trial process is, of course, to ensure that no one who volunteers gets sick or suffers any other adverse consequences as a result of participating in the trial. AIDS vaccines being tested today cannot infect anyone because they only contain harmless genes or proteins from HIV—not the actual virus itself. The idea is to stage a mock war in the body with pieces of the virus that can teach the immune system how to defeat HIV should it ever be confronted by the real thing.

Information about AIDS vaccines that are currently in clinical trials can be found on the HIV Vaccine Trials Network and the International AIDS Vaccine Initiative websites.

In addition, local public health agencies, community-based AIDS and health organizations, and research hospitals are good sources of information about where AIDS vaccine research is being conducted.

More than 70 trials of AIDS vaccines have taken place since 1986, and there currently are a dozen different products in clinical trials. Only one vaccine has moved all the way through all three phases, and it proved unable to thwart transmission through sex or injecting drug use. A phase 3 trial currently is underway in Thailand that involves 16,000 people and two different AIDS vaccines being used in combination: one is made by Sanofi Pasteur, and the other by VaxGen. The next vaccine in the research and development "pipeline" is a phase 2 study of a preparation made by Merck, and it is taking place in several different countries and hopes to enroll 3000 volunteers. The rest of the experimental vaccines that are in human studies are all in much smaller phase 1 and phase 2 trials.


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When to Watch

ENDING AIDS: THE SEARCH FOR A VACCINE now airing on PBS
Check your local listings.