The 15th International AIDS Conference closed here Friday with a call from Nelson Mandela for delegates to return to their countries with a renewed commitment in the battle against the disease.
“History will surely judge us harshly if we do not respond with all the energy and resources that we can bring to bear in the fight against HIV/AIDS,” the former South African president said.
The delegates will take home memories of a week filled with politics and protest but very little science.
Past conferences have been marked by major breakthroughs in drug therapy, increased understanding of how the AIDS virus wreaks havoc on the body and new insights into how some people resist infection.
But there was little of that this week, an indication that research on the disease has reached a plateau and that new milestones are years away.
Vaccine trials and microbicide trials drew some interest this week, but any results are years in the future. Researchers were forced to content themselves with small developments.
Dr. Joel E. Gallant of Johns Hopkins University, for example, had some good news for people suffering from the side effects of antiretroviral therapy.
Although the drugs are valuable in controlling the proliferation of HIV, the virus that causes AIDS, they can cause a marked increase in levels of fats in the blood, leading to abnormal deposits of fat on the abdomen and elsewhere.
Gallant and his colleagues compared a relatively new drug, tenofovir, to the more commonly used stavudine. Each was given in conjunction with another drug, lamivudine. The combination of stavudine and lamivudine is one of the most common as a first-line therapy to people infected with HIV.
Gallant’s team studied 602 patients at 81 centers. Half received the old combination and half the new one. After three years, Gallant said, both combinations were equally good at holding the virus in check. But patients taking the tenofovir combination had significantly fewer side effects and required fewer cholesterol-lowering drugs.
“It’s no longer necessary to choose between potency and tolerability,” he said.
A team from Doctors Without Borders reported new results indicating that copies of brand-name AIDS drugs were as effective as the originals.
The efficacy of such copies has been a major bone of contention here this week because the $15 billion committed by the United States for fighting AIDS over the next five years cannot be used to purchase the copies until they are approved by the U.S. Food and Drug Administration. So far, none of the companies manufacturing the copies have sought such approval.
Dr. Alexandra Calmy of Doctors Without Borders, based in Geneva, said the team gave so-called fixed-dose combinations of drugs to 6,861 patients in Africa, Asia and the Caribbean. The combinations, manufactured in India by Cipla and Ranbaxy Laboratories Ltd., contained stavudine, lamivudine, 3TC and nevirapine and cost no more than $389 per year, compared with the $5,000 or more charged for the name brands.
Calmy said the fixed-dose combination failed to reduce viral replication in about 12% of those tested, about the same percentage as observed in the U.S. with name-brand drugs.
The probability of survival after one year for those taking the fixed-dose combination was 82.4%, again about the same as in the U.S., she said. The incidence of adverse effects was also about the same, and those problems were most often caused by the nevirapine component of the combination.
In another development, pharmaceutical company Roche Holding presented data about one of the newest AIDS drugs, Fuzeon. Formerly known as T-20, Fuzeon is the first of a class of drugs called fusion inhibitors. It is designed to prevent HIV from fusing with the membrane of target cells, the first step in viral entry.
Fuzeon must be administered twice a day via injection, and critics have argued that patients will stop using it because of the pain and inconvenience of the shots.
Dr. Corklin Steinhart of Mercy Hospital in Miami presented results among patients who had been studied for 96 weeks, the longest such trial with the new drug. Half the patients received conventional AIDS drugs and half received the same drugs in addition to Fuzeon.
By the end of the study, he said, more than half the patients who received Fuzeon at the beginning of the study continued to take it. “This dispels the doubts that people wouldn’t stay on it very long,” Steinhart said.
Those who initially responded to Fuzeon continued to respond throughout the course of the study, he said.
Patients in the control group who failed to respond to the conventional therapy were subsequently given Fuzeon, he said. But they did not respond to it as well as those who received it at an earlier stage.
“That means folks who waited didn’t do as well because, most likely, other medicines became less and less effective,” Steinhart said. “The take-home message for me is that Fuzeon should be used as early as possible in treatment.”