Effects of ritonavir on indinavir pharmacokinetics in cerebrospinal fluid and plasma.

Therapeutic control of human immunodeficiency virus type 1 (HIV-1) in peripheral compartments does not assure control in the central nervous system. Inadequate drug penetration may provide a sanctuary from which resistant virus can emerge or allow development of psychomotor abnormalities. To characterize the effect of ritonavir on indinavir disposition into cerebrospinal fluid, seven HIV-infected adults underwent intensive sampling at steady-state while receiving twice-daily indinavir (800 mg) and ritonavir (100 mg).