To determine whether clarithromycin is safe and effective in preventing disseminated Mycobacterium avium Complex in HIV-infected patients with CD4 counts <= 100 cells/mm3.

Inclusion Criteria

Patients must have:

• HIV infection.
• CD4 count <= 100 cells/mm3.
• No evidence of MAC.
• Life expectancy of at least 6 months.

Exclusion Criteria

Concurrent Medication:

Excluded:

• Certain restricted drugs (details not available).

Patients with the following prior conditions are excluded:

History of allergy or hypersensitivity to macrolides. Active substance abuse or other conditions that would affect study compliance.