To evaluate the safety and efficacy of interferon beta (Betaseron) in AIDS and advanced AIDS related complex (ARC) patients receiving a reduced-dose zidovudine (AZT) regimen.

Inclusion Criteria

Concurrent Medication:

Allowed:

• Zidovudine (AZT).

Patient must have:

• Uninterrupted therapy with reduced-dose AZT 500 - 600 mg/day for at least 3 weeks before entry.
• Acceptable hepatic and renal function.
• AMENDED to delete the following sentence:
• Hematologic intolerance to full-dose zidovudine (AZT) (1000 - 1200 mg/day).

Exclusion Criteria

Co-existing Condition:

Patients with the following are excluded:

• Concurrent, ineffectively controlled opportunistic infections.
• Extensive cutaneous and/or visceral Kaposi's sarcoma requiring systemic chemotherapy.
• Proteinuria of 2+ or greater.
• HIV encephalopathy.
• HIV wasting syndrome.
• New York Heart Classification III or IV.
• Uncontrolled angina pectoris.
• Evidence of clinically significant, multifocal uncontrolled cardiac dysrhythmias.

Concurrent Medication:

Excluded:

• Antiretrovirals other than zidovudine (AZT) or Betaseron.
• Chronic acyclovir therapy.
• Acetaminophen.

Patients with the following are excluded:

• Intolerance (hematologic or otherwise) to zidovudine (AZT) at a dose of 100 mg orally every 4 hours. AMENDED to:
• Intolerance at a dose of 500 to 600 mg/day.
• Medical or psychiatric conditions that compromise the patient's ability to give informed consent or complete the study.

Prior Medication:

Excluded within 30 days of study entry:

• Cytotoxic chemotherapy.
• Prior therapy with alpha, beta, or gamma interferons.

Active drug or alcohol abuse.