To study the anti-HIV activity of the various doses of Ro 24-7429 monotherapy based on virologic and immunologic endpoints. To study the safety and tolerance of Ro 24-7429. To explore relationships between exposure to Ro 24-7429 and its metabolites and antiviral activity and drug toxicity. To determine a safe, tolerable, and active dose regimen of Ro 24-7429, and to make preliminary observations of Ro 24-7429 in combination with another antiretroviral nucleoside.

The HIV genome contains a number of genes that regulate viral replication. Control of the activity of these genes and their encoded proteins represents a potential target for development of new antiretroviral drugs. The tat (transactivator of transcription of HIV) antagonist Ro 24-7429 is the first compound for clinical testing that utilizes this approach for therapy of HIV infection.

The HIV genome contains a number of genes that regulate viral replication. Control of the activity of these genes and their encoded proteins represents a potential target for development of new antiretroviral drugs. The tat (transactivator of transcription of HIV) antagonist Ro 24-7429 is the first compound for clinical testing that utilizes this approach for therapy of HIV infection.

Ninety-six patients (four treatment arms of 24 patients each) are randomized to receive oral Ro 24-7429 at 1 of 3 doses or nucleoside control (either zidovudine or didanosine). The study will be blinded only for the arms receiving Ro 24-7429. Treatment continues for 12 weeks. After 12 weeks, patients on the nucleoside control arm receive the highest tolerated dose of Ro 24-7429 in addition to their nucleoside.

Inclusion Criteria

Concurrent Medication:

Allowed:

• Chemoprophylaxis for P. carinii pneumonia, TB, and mucocutaneous candidiasis.
• Methadone maintenance.
• Hormonal contraceptives.

Patients must have:

• HIV-1 seropositivity.
• CD4 count 50 - 500 cells/mm3.
• Life expectancy of at least 24 weeks.
• Stable weight (+/- 2 kg) by 28 days prior to study entry (by history).

NOTE:

• At least 50 percent of patients must be p24 antigen positive (>= 50 pg/ml).

Exclusion Criteria

Co-existing Condition:

Patients with the following symptoms and conditions are excluded:

• Known or suspected hypersensitivity to benzodiazepines.
• Presence of any malignancy other than basal cell carcinoma or limited cutaneous Kaposi's sarcoma (defined as no more than five lesions with no mucosal involvement).
• Ongoing diarrhea, defined as more than 2 liquid stools per day.
• History, physical exam, or laboratory results consistent with a subclinical AIDS-defining opportunistic infection.
• Grade 2 or greater signs and symptoms of AIDS Dementia Complex.
• Evidence of clinically significant cardiac, respiratory, hepatic, gastrointestinal, endocrine, hematologic, psychiatric, neurologic, dermatologic, or allergic disease.

Concurrent Medication:

Excluded:

• Chronic suppressive therapy for CMV, MAI, toxoplasmosis, cryptococcosis, cryptosporidiosis, coccidioidomycosis, and histoplasmosis.
• ddC, ddI, AZT (except for control groups) or other experimental antiretrovirals or immunomodulating agents.
• Other medications excluded from the study.

Patients with the following prior conditions are excluded:

• History of serious adverse reactions to benzodiazepines.
• History of intolerance to AZT at 600 mg/day or less or ddI at 400 mg/day or less.
• History of unexplained fever, defined as a temperature of 38.5 deg C or greater with or without night sweats for more than 7 of the past 28 days.

Prior Medication:

Excluded:

• Benzodiazepines within 14 days prior to study entry.

Active drug or alcohol abuse that would interfere with study compliance.