A Multi-Center, Placebo-Controlled, Double-Blind, Randomized Trial Comparing the Virologic and Immunologic Activities of 400 Mg Nevirapine in Combination With Zidovudine Versus Zidovudine Alone in Asymptomatic HIV-1 Infected Patients With 4-12 Months of Prior Zidovudine Therapy and 200-500 CD4+ Cell

PRIMARY: To compare the virologic activity (quantitative RNA PCR, quantitative PBMC) of the combination of nevirapine and zidovudine (AZT) versus AZT alone after 3 and 6 months of treatment. To compare the effects of these two regimens on CD4 T-cell count and percentage.

SECONDARY: To compare and evaluate other markers of immunologic and virologic activity in patients receiving nevirapine/AZT versus AZT alone. To compare the effects of the two regimens on clinical signs and symptoms. To evaluate the safety and tolerance of the two regimens.

Patients receive combination nevirapine/AZT or AZT alone. Patients are evaluated for virologic and immunologic activity at 3 and 6 months.

Eligibility Criteria:
Inclusion Criteria

Concurrent Medication:

Allowed:

* PCP prophylaxis (trimethoprim-sulfamethoxazole, dapsone, or aerosolized pentamidine), at the discretion of the investigator.
* Antifungal prophylaxis with oral fluconazole or ketoconazole.
* Antiviral prophylaxis for herpes simplex virus with \<= 1000 mg/day oral acyclovir.
* Dilantin for prevention and treatment of seizures.

Patients must have:

* Asymptomatic HIV infection.
* CD4 count 200-500 cells/mm3.
* No prior AIDS.
* No history of or active HIV-related thrush, vaginal candidiasis, zoster (shingles), excessive weight loss, persistent fever, or diarrhea.
* Tolerated 500-600 mg AZT daily for at least 4 months but no more than 12 months immediately prior to study entry.
* Consent of parent or guardian if less than 18 years of age.

NOTE:

* Patients may not co-enroll in another protocol involving other investigational drugs or biologics.

Exclusion Criteria

Co-existing Condition:

Patients with the following symptoms or conditions are excluded:

* Malignancy other than limited cutaneous basal cell carcinoma.
* Psychiatric condition sufficient to impair study compliance.

Concurrent Medication:

Excluded:

* Systemic glucocorticoids and steroid hormones.
* Dicumarol, warfarin, and other anticoagulant medications.
* Cimetidine.
* Tolbutamide.
* Doxycycline.
* Chloramphenicol.
* Phenobarbital and other barbiturates.
* Foscarnet.
* Erythromycin.
* Amoxicillin-clavulanate (Augmentin).
* Ticarcillin clavulanate.
* Biologic response modifiers (alpha interferon, IL-2, immune modulators).
* Any investigational drugs other than study drugs.

Patients with the following prior condition are excluded:

History of clinically important disease other than HIV infection, that may put patient at risk because of participation in this study.

Prior Medication:

Excluded:

* Antiretroviral medications other than AZT.

Excluded within 4 weeks prior to study entry:

* Immunosuppressive or cytotoxic drugs or other experimental drugs.
* Systemic glucocorticoids and steroid hormones.
* Dicumarol, warfarin, and other anticoagulant medications.
* Cimetidine.
* Tolbutamide.
* Doxycycline.
* Chloramphenicol.
* Phenobarbital and other barbiturates.
* Foscarnet.
* Erythromycin.
* Amoxicillin-clavulanate (augmentin).
* Ticarcillin clavulanate.
* Biologic response modifiers (alpha interferon, IL-2, immune modulators).

Required:

* AZT at 500-600 mg/day for at least 4 months but no more than 12 months immediately preceding study entry.

Chronic use of alcohol or drugs sufficient to impair study compliance.