Virologic Responses To New Nucleoside Regimens After Prolonged ZDV or ddI Monotherapy

Inclusion Criteria Concurrent Medication: Recommended: PCP prophylaxis in patients with CD4 count <= 200 cells/mm3. Allowed: Chemophylaxis against Mycobacterium tuberculosis. Acyclovir. Vaccination with pneumococcal vaccine polyvalent. Haemophilus B Conjugate vaccine. Chemoprophylaxis for MAC and Toxoplasma gondii. Antibiotics. Recombinant erythropoietin ( EPO ) and G-CSF. Systemic corticosteroids for < 21 days. Regularly prescribed medications such as antipyretics, analgesics, allergy medications, antidepressants, sleep medications, and oral contraceptives. Vitamins and herbal therapies. Concurrent Treatment: Allowed: Limited local radiation therapy to skin. Blood transfusions if 3 units or less per 21-day period. Acupuncture. Visualization techniques. Patients must have: Completed AZT or ddI monotherapy on ACTG 175 and remained on that regimen during any subsequent interval. Not reached an ACTG 175 endpoint prior to May 1, 1995. Consent of parent or guardian if less than 18 years old. PER AMENDMENT 8/27/96: Patients must be on study/on treatment at the time the protocol study treatment is extended. Exclusion Criteria Co-existing Condition: Patients with the following symptoms or conditions are excluded: Grade 2 or worse peripheral neuropathy. Malignancy requiring systemic therapy. Concurrent Medication: Excluded: Anti-HIV drugs other than study drugs. Biologic response modifiers. Systemic cytotoxic chemotherapy. Any drug known to affect glucuronidation and/or clearance of AZT. Concurrent Treatment: Excluded: Radiation therapy other than limited local therapy to skin. Patients with the following prior condition are excluded: History of acute or chronic pancreatitis. Prior Medication: Excluded: Prior 3TC. Acute therapy for an infection (other than HIV) or other medical illness within 14 days prior to study entry. Current ethanol abuse.