Inclusion Criteria

Concurrent Medication:

Required:

• Aerosolized pentamidine (300 mg monthly) as prophylaxis for PCP only in patients with CD4 count <= 200 cells/mm3.

Allowed:

• PCP prophylaxis with aerosolized pentamidine in patients with CD4 count > 200 cells/mm3, only at the discretion of the treating physician.

Patients must have:

• HIV positivity.
• Absolute CD4 count of 150 - 500 cells/mm3.
• At least 6 months of prior zidovudine therapy.
• No active opportunistic infection requiring ongoing therapy.
• Life expectancy of at least 6 months.

Exclusion Criteria

Co-existing Condition:

Patients with the following symptoms or conditions are excluded:

• Neoplasm other than basal cell carcinoma of the skin.
• Clinically significant cardiac disease.
• Abnormal neurological status by a standardized assessment including strength, reflex testing, and sensory testing.
• Unwilling to comply with protocol requirements.

Patients with the following prior conditions are excluded:

History of myocardial infarction or arrhythmias.

Prior Medication:

Excluded within 2 weeks prior to study entry:

• Antiretroviral agent or interferon.
• Systemic biologic response modifiers, corticosteroids, cytotoxic chemotherapeutic agents, or other drugs that can cause neutropenia or significant nephrotoxicity.
• Rifampin or rifampin derivatives.
• Systemic anti-infectives.

Required:

• At least 6 months of prior zidovudine. Active drug or alcohol abuse.