bed to those newly infected with the virus, as well as AIDS patients.
FDA approved the first drug specifically to combat HIV and AIDS in 1987. Commonly known as AZT (zidovudine), it is in the family of reverse transcriptase inhibitors called nucleoside analogs. Protease inhibitors, the last part of the triple cocktail, have only been on the market about three years. FDA approved the first one, Invirase (saquinavir), in late 1995. Others approved since include Norvir (ritonavir), Crixivan (indinavir), Viracept (nelfinavir), and Agenerase (amprenivir). Viracept was the first of its class to be labeled for use in children and adults. Norvir and Agenerase are now approved for children as well. FDA also has approved Fortovase, a new formulation of saquinavir that comes in a soft gelatin capsule that allows more drug to be absorbed into the body than the earlier version.
Drawbacks of the Regimen
Though the use of protease inhibitors with other AIDS drugs has had a drastic impact on the health of HIV and AIDS patients, there are drawbacks. The HAART treatment is not an AIDS cure, says FDA`s Klein. Though HIV, the virus that causes AIDS, may not be detectable in the blood following successful HAART treatment, experts generally feel that the virus is still present, lurking in hiding spots such as the lymph nodes, the brain, testes, and the retina.
"The improved sense of well-being, and the belief that lower viral load means they will not transmit the virus, has translated, in some communities, to a lapse in certain prevention practices," Klein says. He adds that this is dangerous because infected people, even with diminished viral counts, can spread the virus.
Another concern is that the combination therapy, besides being very expensive, requires a much more complicated treatment regimen. "Patients need to stay aware of and adhere to their dosing schedule," says Klein. "If not taken on a strict regimen, protease inhibitors can result in the emergence of HIV strains that are resistant to treatment." Numerous studies also have shown that viral load can rapidly "rebound" to high levels if patients discontinue part or the entire triple therapy regimen.
AIDS treatments may interact with many commonly prescribed drugs. For example, Pfizer Inc. plans to label its ********* drug ****** to warn of possible interactions with certain protease inhibitors, which appear to raise levels of ****** in the blood.
AIDS drugs also may prompt onset of diabetes or a worsening of existing diabetes and hyperglycemia (high blood sugar), along with increased bleeding in people with hemophilia types A or B.
Common side effects of taking protease inhibitors may include nausea, diarrhea, headache, kidney stones and serious drug interactions. Protease inhibitors may also cause unusual fat deposits, such as in the back of the neck, and high levels of fats and cholesterol in the bloodstream.
Some patients on triple therapy have experienced a type of weight redistribution where face and limbs become thin while breasts, stomach or neck enlarges. Some have nicknamed the appearance of fat deposits at the back of the shoulders "buffalo hump." Fat deposits in the midsection are sometimes called "Crix belly," after the drug Crixivan, "although it has been seen in people taking all approved protease inhibitors," says Klein.
Research is currently under way to determine if protease inhibitors cause a permanent change in fat metabolism.
Pregnant Woman & Children
In 1998 recommendations, the Public Health Service Task Force stated that the decision to take anti-HIV drugs during pregnancy should be made by the pregnant woman after her health care-provider has explained benefits and risks. There are some compelling reasons to take the drugs. For example, an HIV-positive pregnant woman who takes AZT after the first trimester decreases the chance of the baby being born with HIV. Studies show that AZT taken according to a strict regimen decreases by nearly 66 percent the odds of infecting the newborn.
The task force says women should consider delaying therapy until after the 10