"You First"

Any new drug or vaccine must undergo years of laboratory analysis in test tubes and animals before it ever reaches the public. But there always comes a point when people have to serve as guinea pigs. Last week officials at the National Institute of Allergy and Infectious Diseases in Bethesda, Md., announced that the first U.S.-approved human tests of a potential AIDS vaccine would begin this fall. The preparation, developed by MicroGeneSys of West Haven, Conn., consists of the outershell protein of the AIDS virus, which researchers hope will stimulate the body into producing an immune response against the intact invader. Says NIAID Director Anthony Fauci: "This is the first step in what will be a long process toward developing a vaccine to prevent AIDS."

The experimental injection departs from traditional vaccines, which are made from weakened or killed viruses. Reason: the AIDS virus is so dangerous, scientists fear that once inside the body, even a killed version could revive itself and prove deadly. Thus the MicroGeneSys product, called VaxSyn, and most other AIDS vaccines under development depend on using only parts of the virus in the hope that these bits and pieces will spark enough immune protection.

In October doctors will administer VaxSyn to 60 homosexual men from the Washington area. To qualify, volunteers must be free from AIDS virus infection and agree to use "safe sex" practices. After counseling, they must also sign a three-page consent form explaining the risks of participation and pass a quiz to confirm that they understand the experiment.

The greatest danger faced by volunteers is anaphylactic shock, a sometimes fatal but rare overreaction of the immune system to a foreign substance. A more probable response, says Fauci, will be redness and soreness at the site of the injection, and perhaps a fever. Although no one can get AIDS from the vaccine, recipients who respond to the inoculation may come up positive on the AIDS antibody-screening test. Other tests, however, will show that they are not really infected by the virus. Another potential drawback: the injection could impair the response to a future, more powerful vaccine. Still, NIAID has found many willing applicants, evidently motivated by a sense of responsibility to help end the epidemic.

The main goal of the first six-month trial will be to assess the vaccine's safety. If all goes well, scientists will eventually try to determine its efficacy in preventing infection by administering it to large groups of people at high risk of developing AIDS. The answer is hardly around the corner. Says Fauci: "It will be a considerable time, probably the mid-1990s, before any vaccine, including this one, will be ready for general use."