To determine the safety profile and maximum tolerated dose (MTD) of recombinant soluble human CD4 (rCD4) therapy in patients with AIDS or AIDS related complex (ARC). To assess pharmacokinetic properties of rCD4 in humans. To obtain a preliminary indication of the antiviral effects of rCD4 in patients with AIDS and AIDS related complex (ARC).

Inclusion Criteria

Patients must have:

• HIV-1 seropositivity.
• Diagnosis of AIDS or AIDS related complex (ARC).
• Failure to tolerate or respond to zidovudine (AZT) or decided to decline AZT therapy.
• The ability to sign a written informed consent form prior to treatment.
• A willingness to abstain from all other experimental therapy for HIV infection during the entire study period.
• A life expectancy of at least 3 months.

Exclusion Criteria

Co-existing Condition:

Patients with the following conditions or symptoms are excluded:

• Serious active opportunistic infections.
• Malignancies other than Kaposi's sarcoma.

Concurrent Medication:

Excluded:

• Zidovudine (AZT).
• Corticosteroids.
• Nonsteroidal anti-inflammatory agents (NSAI).
• Other experimental therapy.

Patients with the following are excluded:

• Serious active opportunistic infections.
• Malignancies other than Kaposi's sarcoma.

Prior Medication:

Excluded within 3 weeks of study entry:

• Zidovudine (AZT).
• Chemotherapy.
• Immunomodulators.
• Other experimental therapy.