Human pharmacokinetics of chloroquine and proguanil delivered in a single capsule for malaria chemoprophylaxis.

Two antimalarial prophylactic regimens were compared in 17 healthy volunteers. Regimen A consisted of daily ingestion of a single capsule containing 100 mg base chloroquine (CQ) and 200 mg proguanil (PG). Regimen B consisted of daily ingestion of separate tablets of CQ (100 mg base) and PG (two 100 mg tablets). Both treatments lasted for 12 days. Effective chloroquine levels were reached after 72 hours with both regimens (49.9 ng/ml for treatment A and 36.7 ng/ml for treatment B). Proguanil and cycloguanil plasma levels were significantly lower on sampling obtained at H3 (three hours later) and H6 (six hours later) on day 1 in the regimen A (p < 0.002). Thereafter there were no significant difference between the two regimens. Both regimens were well tolerated, but regimen A using the capsule appeared better accepted and facilitates compliance.