Inclusion Criteria

Concurrent Medication:

Allowed:

• IV gammaglobulin therapy.
• Medications for PCP prophylaxis (e.g., TMP / SMX, dapsone, aerosolized and IV pentamidine).
• Fluconazole.

Patients must have:

• HIV infection. A positive Polymerase Chain Reaction (PCR) is not acceptable as the sole evidence of HIV infection. Three out of five children in each age and dose group must have a serum p24 antigen level of 70 pg/ml or greater and/or a plasma viral titer of 50 TCID/ml or greater prior to study entry.
• Ability to be followed by their original trial center for the duration of the trial.
• Consent of parent or guardian.

Exclusion Criteria

Co-existing Condition:

Patients with the following symptoms and conditions are excluded:

• Lymphocytic interstitial pneumonitis if steroid-dependent or requiring supplemental oxygen or with a pretreatment paO2 < 70 mm Hg.
• Opportunistic or serious bacterial infections within 28 days prior to entry.
• Demonstrated intolerance to zidovudine prior to administration of nevirapine (in patients enrolled in the combination therapy phase of the study).
• CDC classification of P-2D (secondary infectious diseases) and/or P-2E (secondary cancers).
• Pre-existing malignancies.

Concurrent Medication:

Excluded:

• Other approved or investigational antiretroviral agents.
• All other investigational agents (except fluconazole).
• Glucocorticoids and steroid hormones.
• Dicumarol, warfarin, and other anticoagulants.
• Digitoxin.
• Valproic acid.
• Tolbutamide.
• Doxycycline.
• Chloramphenicol.
• Isoniazid.
• Phenobarbital and other barbiturates.
• Hepatotoxic drugs.

Patients with prior participation in this trial are excluded.

Prior Medication:

Excluded:

• More than 6 weeks of prior zidovudine (AZT) therapy or more than 6 weeks of any other antiretroviral therapy.

Excluded within 7 days prior to study entry:

• AZT (in monotherapy groups only).

Excluded within 4 weeks prior to study entry:

• Other approved or investigational antiretroviral agents.
• All other investigational agents.
• Glucocorticoids and steroid hormones.
• Dicumarol, warfarin, and other anticoagulants.
• Digitoxin.
• Valproic acid.
• Tolbutamide.
• Doxycycline.
• Chloramphenicol.
• Isoniazid.
• Phenobarbital and other barbiturates. Active alcohol or drug abuse to impair compliance with the protocol.