The purpose of this study is to see if it is safe and effective to give CPI-1189 to patients with AIDS dementia.

Advanced HIV infection can cause AIDS dementia (brain damage due to HIV leading to loss of memory and muscle control). CPI-1189 may be able to postpone AIDS dementia or slow it down.

Late-stage HIV infection can cause AIDS dementia (brain damage due to HIV leading to loss of memory and muscle control). CPI-1189 may be able to postpone AIDS dementia or slow it down.

Patients are randomized to receive either placebo or one of two oral doses of CPI-1189 daily. Patients are assessed for safety and tolerability during Weeks 2, 6, and 10. At Week 10, efficacy assessments are also made. For those who volunteer, a sample of cerebrospinal fluid is obtained at baseline and at Week 10. Blood samples for CPI-1189 pharmacokinetic trough measurements are taken at Weeks 2 and 10. The open-label phase starts at Week 11. At Weeks 13 and 16, a safety evaluation is performed. At the end of the open-label phase, Week 22, a final set of safety and efficacy assessments and a blood sample for CPI-1189 pharmacokinetic trough measurement are obtained.

Inclusion Criteria

You may be eligible for this study if you:

• Are HIV-positive.
• Are at least 18 years old.
• Have symptoms of AIDS dementia including forgetfulness, loss of concentration, slow mental processing, or a loss of muscle control.
• Have been on stable anti-HIV drug therapy for the past 6 weeks (if you are taking anti-HIV drugs).

Exclusion Criteria

You will not be eligible for this study if you:

• Have certain serious medical conditions, such as a mental disorder or an opportunistic (AIDS-related) infection.