Steady-State Bioavailability of Extended-Release Methylphenidate (MPH-MLR) Capsule vs. Immediate-Release Methylphenidate Tablets in Healthy Adult Volunteers

Objectives The objective of the study was to determine the relative bioavailability of an extended-release multilayer bead formulation of methylphenidate hydrochloride (MPH-MLR) 80 mg vs. methylphenidate immediate-release (IR; Ritalin ® ) tablets as single and multiple doses in the fed state. Methods A single-center, multiple-dose, randomized, open-label, two-period crossover study conducted in 26 healthy adults assigned to 4 days of once-daily MPH-MLR 80 mg or IR methylphenidate 25 mg three times daily. Results MPH-MLR 80 mg produced reproducible biphasic profiles of plasma methylphenidate concentrations characterized by a rapid initial peak, followed by a moderate decline reaching a plateau ~5 h post dose, then a gradual increase culminating in an attenuated second peak ~7 h post dose. Maximum concentration was lower for MPH-MLR 80 mg than IR methylphenidate 25 mg three times daily on day 1 (23.70 vs. 31.47 ng/mL); exposure was similar. The geometric mean ratios (MPH-MLR/IR methylphenidate [90 % CI]) of log-transformed area under the plasma drug concentration-time curve to the last measurable observation (day 1: 0.88 [84.75–91.80]; day 4: 0.84 [81.16–86.94]), and area under the plasma drug concentration extrapolated to infinity (day 1: 0.93 [88.57–97.28]; day 4: 0.88 [84.48–91.17]) were within the 80–125 % bioequivalence range. The mean ± SD MPH-MLR 80-mg capsule day 4 area under the plasma drug concentration vs. time curve from 0 to 4 h (74.5 ± 15.2 ng·h/mL) was greater than IR methylphenidate 25 mg three times daily (66.0 ± 17.4 ng·h/mL), confirming steady-state levels during the study period. All treatment regimens were safe and well tolerated. Conclusion MPH-MLR 80-mg capsule once daily or IR methylphenidate 25 mg three times daily provides comparable maximum methylphenidate concentrations and systemic exposure in the fed state.