Successful Primate Trials Encourage Researchers Seeking AIDS Vaccine, Associated Press Reports

An Associated Press article highlighting scientists' "optimis[m]" about successful AIDS vaccination trials with primates was featured in many newspapers nationwide on Sunday. In one trial, at Emory University's Yerkes Regional Primate Research Center, a four-year-old macaque monkey named Godot received an experimental AIDS vaccine and was then injected with SHIV -- an amalgam of the human and simian versions of the AIDS virus. Godot is "infected but otherwise healthy" after receiving the vaccine, which researchers hope will become the "model" for a human AIDS vaccine. Two variations of the same approach have been used, with similar results, in primate tests conducted by Harvard Medical School and Merck & Co.. The Merck vaccine is in first-stage human testing, and the Yerkes and Harvard versions may begin within six months. While an AIDS vaccine is "still no sure bet," researchers believe they are "on a path toward finding one." The new vaccines are "designed to accomplish the next best thing" to reversing HIV infection, by "train[ing] the immune defenses to hold an infection in check without preventing it entirely." The vaccines are designed to start an immune system counterattack "more quickly" so that fewer cells are infected and the virus "plateaus" at a lower level. The vaccine may allow HIV-positive people to live with the virus for their entire lifetime, and by keeping viral levels low, such a vaccine may also make those individuals less infectious (AP/Baltimore Sun, 8/26).