New developments in HIV treatment

Various researcherse unveiled new findings that offer encouragement to millions of patients infected with the HIV virus and AIDS at the 12th World

Clinical investigators for Wilmington, DE-based DuPont Co. made the biggest splash with the announcement that combining Sustiva™ (efavirenz), a nucleoside reverse transcriptase inhibitor in development, once daily with a new twice-a-day pill that combines Glaxo Wellcome's Retrovir® (zidovudine, AZT) and Epivir® (lamivudine, 3TC) significantly suppressed the virus after 36 weeks of treatment.

The regimen would reduce the number of pills patients take from 10 to 20 pills per day to three. Easier dosing regimens could boost patient compliance, and help them avoid drug-resistant strains of the virus. In developing areas, where adequate drinking water is scarce, adhering to the demands of older regimens is difficult and, in some areas, impossible.

In other clinical trials, researchers found that combining Sustiva with a standard three-drug regimen of Crixivan® (indinavir) and two nucleoside analogues in therapy-experienced patients significantly reduced the level of virus in those patients within eight weeks of treatment. Crixivan is a Merck & Co. product.

Also, researchers reported, combining Sustiva with Viracept® (nelfinavir), a protease inhibitor from Agouron Pharmaceuticals, reduced viral load and elevated CD4 cell counts in both patients who had already been treated and in those who had never been treated. The report was based on data results from 63 patients who had received treatment for 16 weeks.

However, similar to other HIV therapies, Sustiva does produce side effects, including rash, nausea, dizziness, diarrhea, headache and insomnia. It may also be unsuitable for use by pregnant women.

Other developments

Glaxo Wellcome also announced significant research findings at the Geneva conference.

In clinical studies, amprenavir, a phase III product Glaxo Wellcome is developing with Vertex Pharmaceuticals Inc., suppressed viral load and may actually help the immune system regain strength when it is administered with abacavir, a nucleoside reverse transcriptase inhibitor.

In eight of nine previously untreated patients who were in the early stages of chronic HIV infection had undetectable viral loads after 48 weeks of therapy. Patients also demonstrated nearly normal levels of white blood cells after 48 weeks of treatment, raising the question of whether or not an HIV-infected immune system can "repair" itself. PR