A Phase I Study of the Safety and Pharmacokinetics of Recombinant CD4 (rCD4) in Infants and Children Infected With or at Risk for HIV Infection

Inclusion Criteria Concurrent Medication: Allowed: * Prophylactic medication for patients with previous documented episodes of Pneumocystis carinii pneumonia (PCP). * Concomitant zidovudine (AZT) or intravenous gamma globulin (IVIG) during maintenance therapy phase of the study. AMENDED: As of 10/19/90 only Children 0 to 3 months are being enrolled. Original design: Patients must be infected with HIV or at risk for HIV infection. They must be one of the following: * Asymptomatic. * Mildly symptomatic but not eligible for and/or decline ACTG protocol 052. * Markedly symptomatic but not eligible for and/or decline ACTG protocol 051 or cannot tolerate zidovudine (AZT) therapy. All patients must have: * A life expectancy of at least 3 months. * A legally-qualified guardian with the ability to sign a written informed consent form, which must be obtained prior to treatment. A willingness to abstain from all other experimental therapy for HIV infection during the entire study period. Exclusion Criteria Concurrent Medication: Excluded: * Zidovudine (AZT). * Intravenous gamma globulin (IVIG). * Pentamidine. * Trimethoprim / sulfamethoxazole (TMP/SMX). * Corticosteroids. * Nonsteroidal anti-inflammatory agents (NSAIDS). * Other known immunomodulatory agents. * All other experimental therapies. Patients will be excluded from the study for the following reasons: * Serious active opportunistic infection or malignancies prior to study entry. * Defined organ insufficiencies. Prior Medication: Excluded within 3 weeks of study entry: * Zidovudine (AZT). * Intravenous gamma globulin. * Cancer chemotherapy. * Immunomodulatory agents. * Other experimental therapy. Patients may not have any of the following diseases or symptoms: * Serious active opportunistic infection or malignancies prior to study entry. * Cardiopathy. * Two or more episodes of prior Pneumocystis carinii pneumonia (PCP). * Hematologic insufficiency defined as granulocytes = or \< 1000 cells/mm3; platelets = or \< 100000 cells/mm3; hemoglobin = or \< 8 g/dl. * Renal insufficiency defined as creatinine \> 2 mg/dl; = or \> 5 white blood cells or red blood cells/hpf or = or \> 2+ proteinuria in urine. * Hepatic insufficiency defined as bilirubin = or \> 3 x upper limit of normal; SGOT = or \> 10 upper limit of normal.