Inclusion Criteria

Inclusion Criteria

Concurrent Medication:

Allowed:

- Acyclovir (if patient is also receiving ddC, clinical monitoring should be more
frequent).

- Analgesics, antiemetics, antidiarrheal agents, or other necessary treatment for
symptomatic therapy.

- Interferons for maintenance therapy of Kaposi's sarcoma.

- GM-CSF.

Required:

- Prophylaxis against Pneumocystis carinii pneumonia (PCP) if their absolute CD4+
lymphocyte count is < 200 cells/mm3 at study entry. PCP prophylaxis for patient with
CD4+ counts between 200 and 300 cells/mm3 is at discretion of patient's primary
physician.

- NOTE: There is potential interaction of ddI and dapsone.

Concurrent Treatment:

Allowed:

- Transfusion, erythropoietin.

Patients must have the following:

- Zidovudine (AZT) failure after having received a cumulative duration of at least 6
months.

- AZT intolerance - rechallenge is not required for patients exhibiting = or > grade
III cutaneous symptoms.

- Diagnosis of AIDS or CD4+ = or < 300 cells/mm3 OR AIDS-defining illness other than
Kaposi's sarcoma.

- Willingness and ability to comply with protocol.

- Informed consent must be obtained for all study participants in accordance with state
law, local IRB requirements, and 45 CFR Part 46. AMENDED 11/19/90 to include assent
by minors if they are physically able, in addition to consent by parents.

Exclusion Criteria

Co-existing Condition:

Patients with the following conditions or symptoms are excluded:

- Any disorders for which the study drugs are contraindicated (didanosine (ddI)) is
contraindicated in renal impairment, heart disease, receiving renal dialysis.

- Active opportunistic infection.

Concurrent Medication:

Excluded:

- Other antiretroviral agents.

- Use of drugs associated with peripheral neuropathy or use of agents that may cause
pancreatitis including intravenous pentamidine and alcohol should be restricted or
avoided.

Concurrent Treatment:

Excluded:

- Other concurrent antiretroviral clinical trials.

Patients with the following are excluded:

- History of pancreatitis, peripheral neuropathy, uncontrolled seizures, renal
impairment, heart disease, stage 2 or higher ADC.

- Any other disorders for which the study drugs are contraindicated, i.e., ddI is
contraindicated in renal impairment, patients receiving renal dialysis, and heart
disease.

- Receiving acute therapy for active AIDS defining opportunistic infection on
enrollment.

Prior Medication:

Excluded:

- Didanosine (ddI).

- Dideoxycytidine (ddC) .

Excessive alcohol use that, in investigator's opinion, puts patient at risk of developing
pancreatic disease.