Inclusion Criteria

Inclusion Criteria

Concurrent Medication:

Required:

- PCP prophylaxis for patients with CD4 count < 200 cells/mm3 or a prior history of
PCP.

Allowed:

- Trimethoprim with sulfamethoxazole or dapsone, intravenous pentamidine, atovaquone,
primaquine-clindamycin or trimetrexate for acute PCP.

- Topical antifungals, clotrimazole, ketoconazole, fluconazole, and amphotericin B for
treatment of mucosal and esophageal candidiasis.

- Prophylaxis or therapy for opportunistic infections, as indicated, with other
medications such as itraconazole, isoniazid, pyrazinamide, clofazimine,
clarithromycin, azithromycin, ethambutol, amikacin, ciprofloxacin, ofloxacin,
pyrimethamine, sulfadiazine, and clindamycin.

- Maintenance therapy for opportunistic infections as long as patients have been on a
stable dosage regimen for 1 month prior to study entry.

- Ganciclovir for CMV retinitis or gastrointestinal disease as long as patients have
been on a stable dose for at least 1 month prior to study entry with no grade 3 or 4
neutropenia or dependence on G-CSF.

- Acyclovir (<= 1000 mg/day) for maintenance of herpes simplex virus infections.

- Erythropoietin or G-CSF if clinically indicated.

- Antibiotics for bacterial infections unless specifically excluded.

- Rifampin or rifabutin.

- Symptomatic treatments such as antipyretics, analgesics, and antiemetics.

Concurrent Treatment:

Allowed:

- Local radiation therapy.

Prior Medication: Required:

- At least 6 months of prior cumulative nucleoside therapy with AZT, ddI, or ddC, given
as monotherapy or in combination.

Patients must have:

- Prior or current documentation of HIV seropositivity by ELISA confirmed by Western
blot, positive HIV antigen, or positive HIV culture, or a second antibody test by a
method other than ELISA.

- CD4 count <= 350 cells/mm3.

- Prior cumulative nucleoside therapy of >= 6 months.

- Consent of parent or guardian if less than 18 years of age.

Exclusion Criteria

Concurrent Medication:

Excluded:

- Antiretroviral therapies other than study medications.

- Systemic corticosteroids given consecutively for > 21 days.

- Induction or maintenance with foscarnet.

- Systemic cytotoxic chemotherapy for a malignancy.

- Erythromycin.

- Coumadin/warfarin.

- Phenytoin or phenobarbital.

- Amoxicillin/clavulanate acid (Augmentin) or ticarcillin/clavulanate acid (Timentin).

Patients with the following prior conditions are excluded:

- History of pancreatitis.

- History of intolerance to 500 or 600 mg/day AZT or to 400 mg/day ddI tablets or 500
mg/day ddI sachets.

- History of grade 2 or worse peripheral neuropathy.

Prior Medication:

Excluded at any time:

Prior non-nucleoside reverse transcriptase inhibitors (NVP; L697,611; TIBO; atevirdine).

Excluded within 14 days prior to study entry:

- Acute treatment for a serious infection or any opportunistic infection.

- Biologic response modifiers such as interferon and IL-2.

- Erythromycin.

- Coumadin/warfarin.

- Phenytoin or phenobarbital.

- Ticarcillin/clavulanate acid (Timentin) or amoxicillin/clavulanate acid (Augmentin).