An Open-Label, Staggered Rising Dose Cohort Study Assessing the Pharmacokinetics, Safety, and Tolerance of BI-RG-587 in Combination With Zidovudine in Patients With HIV Infection (CD4+ Cell Count < 400/mm3)

To assess the safety and tolerance of multiple oral doses of nevirapine in combination with zidovudine (AZT); to get information on the pharmacokinetics (blood levels) and dose proportionality of nevirapine/AZT with multiple dosing; to characterize the pattern of virological activity in vivo (in humans) of nevirapine in combination with AZT; to determine whether development of resistance to either drug is slowed by the use of the combination. Drugs now used in treatment for patients with AIDS show some toxicity which limits their usefulness. In addition, with long-term treatment with AZT, there is evidence of virus resistance to the drug. Compounds that are more effective and less toxic than those in present use would be beneficial, especially if they are active against AZT-resistant viruses. Nevirapine has shown in vitro (test tube studies) activity in inhibiting HIV replication (reproduction). In vitro studies have shown that nevirapine and AZT work together to inhibit HIV replication.