Study shows three drugs better than two

NIAID terminates trial; allows patients to switch

AIDS patients taking a combination of three drugs survived significantly longer than those taking two, underscoring the importance of hitting hard with treatment for advanced HIV disease, say federal health officials.

"The results of ACTG 320 confirm the importance of including protease inhibitors in treatment strategies for patients with advanced HIV disease," says Anthony Fauci, MD, director of the National Institute of Allergy and Infectious Diseases. "Significantly, the current study provides additional evidence that combination approaches using protease inhibitors can reduce the risk of death."

The trial evaluated the efficacy and safety of indinavir (Crixivan) in combination with either zidovudine (AZT) or stavudine (d4T) and lamivudine (3TC), compared to AZT or d4T and 3TC alone.

The 1,156 patients had CD4 counts below 200 (mean baseline CD4 count was 86) and had taken AZT for at least three months. However, they had received less than one week of 3TC and no protease inhibitors. Patients were followed for 38 weeks, with some having up to one year of treatment.

For the triple combination group, there were 33 instances of disease progression (including opportunistic infections and deaths), compared to 63 for the two-drug group. Deaths totaled 18 for the double-drug arm and eight for the triple-drug arm.

"The significant reduction in disease progression conferred by indinavir when given as part of a three-drug combination . . . suggests that further benefits can be achieved with regimens of ever-increasing potency," says Scott Hammer, MD, professor of medicine at Harvard University and protocol chair of the trial.

The study, which also showed no major differences in the two groups in safety or toxicity, was stopped in late February, allowing patients to switch over to the triple-drug regimen.