ADVAX, new DNA vaccine in human trial; HIV-negative volunteers needed in New York City or Rochester, NY areas.

A new HIV vaccine called ADVAX, developed by scientists in Dr. David Ho's Aaron Diamond AIDS Research Center laboratory, needs volunteers in the New York City or Rochester, New York area, to test its ability to generate an immune response to HIV in healthy subjects.

ADVAX is different from other vaccines in important ways. All vaccines must deliver proteins to stimulate the body's immune response, and most of them just inject the proteins. But ADVAX is a DNA vaccine; instead of providing the proteins directly, it provides completely synthetic DNA that instructs the body's cells to create the proteins desired. This can make the proteins easier for the immune system to recognize--and laboratory tests show that this vaccine produced the desired proteins in large amounts.

And ADVAX differs from all other vaccines in that it codes for five HIV genes (ENV, GAG, POL, and a NEF/TAT fusion protein). Other vaccines code for only one, two, or at most three HIV genes, While designed as a preventive vaccine, ADVAX will also be tested for treatment of persons already infected with HIV, if it shows good results in the current study.

ADVAX was designed specifically against the clade C HIV subtype found in China; clade C also causes the huge epidemic in Southern Africa, but is seldom found in the U.S. Even if this vaccine does work against clade C, it is not known how much if any effectiveness would carry over to the clade B virus that causes most of the epidemic in the U.S. and Europe. But a positive result with clade C would be a huge advance in the science of HIV prevention and treatment, and a similar product could be developed for clade B if necessary.

This trial is being conducted at two medical centers, Rockefeller University Hospital in New York City, and the University of Rochester in Rochester, New York. Volunteers must be HIV-negative, ages 18 to 45, and not at high risk of HIV infection (they cannot be using injection drugs or have been commercial sex workers, and must use safer-sex practices when needed). There are additional medical entry criteria as well. The trial involves 12 visits over 18 months, including three injections, at 0, 1, and 3 months.

Volunteers who receive this vaccine might test positive on conventional HIV antibody tests, even though they are not infected. However, it is easy to distinguish a positive result caused by the vaccine from one caused by an infection, by testing for the HIV virus itself (instead of testing for the antibodies). The Aaron Diamond center is prepared to do this testing if anyone needs it; and commercially available viral load tests would also work, since they would show an undetectable viral load for a person not on antiretroviral treatment, which almost never happens if someone has HIV infection. Volunteers will receive an official letter explaining the trial, and stating that they might test positive on an HIV antibody test even though they are not infected.

Thirty volunteers have already received the vaccine, and 15 more are needed. For more information about volunteering, contact Elizabeth Londono at The Aaron Diamond AIDS Research Center, 212-448-5126, or at [e-mail]. In Rochester call Patrick Fisher, 585-275-0459.