Pharmacokinetics of remoxipride controlled release and immediate release capsules in schizophrenic patients

Single dose and steady-state pharmacokinetics of remoxipride, a new antipsychotic drug, were compared after administration of a controlled release capsule (CR) and an immediate release capsule (IR), both 200 mg and administered b.i.d. Thirteen patients with chronic schizophrenia entered the double-blind 6-week crossover study. Seven were evaluable for investigation of steady-state pharmacokinetics. Fluctuations in plasma remoxipride concentrations decreased considerably after remoxipride CR compared with the IR formulation. The plasma peak concentrations were significantly decreased and the trough values were increased after the CR formulation, although the average concentrations at steady-state were similar. The two formulations were bioequivalent regarding the amount of remoxipride absorbed after repeated dosing. Five out of 13 patients withdrew prematurely from the study because of ineffectiveness or refusal of treatment. Both formulations were well tolerated.