Open-Label, Randomized, Single-Dose, 2-Period, 2-Sequence Crossover, Comparative Pharmacokinetic Study to Evaluate Bioequivalence of 2 Oral Formulations of Olanzapine under Fasting and Fed Conditions

Olanzapine, a second-generation atypical antipsychotic drug, is widely used for schizophrenia and moderate to severe mania associated with bipolar disorders. This open-label, randomized, single-dose, 2-sequence, 2-period crossover, comparative pharmacokinetic study assessed the bioequivalence of 5 mg of olanzapine administered in tablet (R) or disintegrating tablet (T) formulation in healthy Chinese volunteers under both fasting and fed conditions. Numbers of enrolled subjects were 30 and 24 for fasting and fed treatments, respectively. Blood samples were drawn and collected predose as well as up to 144 hours postdose. The plasma concentration of olanzapine was quantitated by a robust, rapid, and sensitive liquid chromatography-tandem mass spectrometry method. The R was bioequivalent to T formulation under either fasting or fed conditions. The 90%CI for ratios of the geometric means observed maximum plasma concentration, area under the curve from time 0 extrapolated to last time point, and area under the curve from time 0 extrapolated to infinity were all within the allowed limit (80.0% to 125.0%). The pharmacokinetic profiles of T and R formulations were similar under fasting and fed conditions. Both formulations were well tolerated, with a similar incidence of treatment-emergent adverse events under fasting and fed conditions.