Exclusion Criteria

Co-existing Condition:

Patients with the following are excluded:

• Prior history of a malignancy other than cutaneous basal cell or cervical carcinomas.
• Other significant, chronic underlying medical illness which would impair study completion.
• Liver dysfunction as demonstrated by lab results.
• Laboratory evidence of compromised bone marrow function.

Concurrent Medication:

Excluded:

• Any other experimental agents.
• Any probenecid-containing product.

Patients are excluded if they have a history of symptoms characteristic of CDC class I or IV including any of the following:

• Unintentional weight loss of greater than 10 lbs, or more than 10 percent of usual body weight within the last 16 weeks.
• Unexplained fever > 38.5 degrees C on more than 14 consecutive days or on more than 15 days in the previous 30-day period.
• Unexplained diarrhea defined by = or > 2 liquid stools per day persisting for = or > 14 days or 15 days in any 30-day period.
• OR History of secondary infections associated with AIDS related complex (ARC) including:
• Recurrent oral candidiasis documented by morphology or by response to antifungal therapy within 3 years.
• Herpes zoster infection within 3 years.
• Oral hairy leukoplakia at any time.
• OR History of opportunistic disease fulfilling the CDC surveillance definition of AIDS.
• Signs and symptoms at baseline characteristic of acute HIV disease (CDC group I).
• Evidence of significant neurologic dysfunction as currently defined by CDC following standard neurologic screening and AIDS Dementia Assessment.

Prior Medication:

Excluded:

- Previous treatment for greater than 3 months duration with any antiretroviral compound such as zidovudine (AZT).

Excluded within 4 weeks of study entry:

- Treatment with any potentially myelosuppressive drug, nephrotoxic agent, or other experimental therapy.

Excluded within 3 months of study entry:

- Antiretroviral drugs or biologic response modifiers.

Excluded within 4 months of study entry:

- Systemic corticosteroids.

Patients must meet the following criteria:

• HIV infection demonstrated by ELISA and confirmed by Western blot.
• Signs and symptoms of HIV disease limited to those characteristic of CDC groups II (asymptomatic) and III (persistent generalized lymphadenopathy - PGL).
• Ability to give informed consent.
• Willingness to be followed by the originating medical center for the entire 3-year duration of the study.

Active drug or alcohol abuse sufficient in the investigator's opinion to prevent compliance with the study regimen.