Simpler drug combinations can control the AIDS virus well, researchers said on Sunday in several reports that will help in trying to mix and match nearly two dozen different HIV drugs in lifesaving cocktails.
The reports published in the Journal of the American Medical Association, and presented to the International AIDS Conference in Toronto, show that simplified drug regimens can be safe and effective, and safely relieve side-effects in some patients.
The HIV drugs, called antiretroviral drugs, are usually combined into three-drug cocktails called highly active antiretroviral therapy or HAART. They once had to be carefully planned out, with patients forced to take several different pills at various times of day.
Now combined pills make that easier — with one once-a-day pill on the market. And some patients might safely skip some of the more toxic drugs, the studies suggest.
“We now have 22 antiretroviral agents in five classes that are FDA (U.S. Food and Drug Administration) approved,” Dr. Scott Hammer of Columbia University in New York told a news conference.
Some are clearly meant for patients who have few options because the virus in their bodies has evolved to resist most drugs. These include many of the newer drugs.
But there is clear evidence that some of the mainstay drugs can keep the virus suppressed, which in turn keeps the immune system, and patients, healthy.
“Despite the optimism, we are still faced with lots of drug toxicity issues,” Hammer said. And if people take one drug, the virus can develop something called cross-resistance to other drugs.
Guidelines issued on Sunday by the non-profit International AIDS Society-USA are aimed at sorting through the choices, and mesh with World Health Organization guidelines.
When to start and what to start with
Both groups say a new HIV patient should start taking the drugs as soon as the immune system cells that are destroyed by the virus reach a certain level.
And they should start on a three-drug combination of the oldest class of HIV drugs, called nucleoside or nucleotide reverse transcriptase inhibitors, along with either a non-nucleoside reverse transcriptase inhibitor (NNRTI) or a protease inhibitor.
Because protease inhibitors are expensive, WHO recommends waiting until they are needed.
The first once-a-day pill to hit the market, Atripla, meets these guidelines. A cooperative venture by Gilead Sciences Inc., which makes the NRTIs Emtriva and Viread, with Bristol-Myers Squibb, which makes the NNRTI Sustiva, the pill contains one of the recommended three-drug regimens.
There are also generic drugs made in Thailand, Brazil and elsewhere, as well as two-and three-drug combinations that can be taken twice a day with other drugs.
Other research suggests it may be safe to leave out some of the drugs.
Susan Swindells of the University of Nebraska Medical Center Omaha and colleagues tested the use of atazanavir, a protease inhibitor sold under the name Reyataz by Bristol-Myers Squibb, combined with a small dose of another protease inhibitor called ritonavir — known as “boosting.”
They tested it on 34 patients who had been taking a three-dose combination and found the once-a-day, two-dose regimen kept them just as healthy.
“I don’t think it is ready for the general public,” commented Hammer, who also worked on the study.
A third study tested whether adding a fourth drug to the mix would help new HIV patients get the virus under control more quickly, but found it did not help any, and cost more.