Single-dose Pharmacokinetic Properties and Relative Bioavailability of a Novel Methylphenidate Extended-release Chewable Tablet Compared With Immediate-release Methylphenidate Chewable Tablet

Abstract

Purpose: A novel methylphenidate hydrochloride extended-release chewable tablet (MPH ERCT) was developed to potentially address an unmet need for patients with attention-deficit/hyperactivity disorder, especially children, who cannot or will not swallow tablets or would prefer the convenience of a chewable tablet. This randomized, open-label, crossover trial compared the pharmacokinetic properties and relative bioavailability of MPH ERCT with an MPH chewable immediate-release tablet (IR MPH) formulation in healthy adults.

Methods: Healthy men and women 18 to 55 years of age were randomly assigned to MPH ERCT 40 mg or 40 mg IR MPH administered in 2 equal doses of 20 mg 6 hours apart with a 7-day washout period. Plasma concentrations of MPH at selected time points up to 24 hours were measured, and pharmacokinetic parameters were determined using a noncompartmental approach in the SAS (Version 9.2) PROC general linear model procedure.

Findings: A total of 33 participants were enrolled in the study; 31 participants were included in the pharmacokinetic analysis. The exposure ratios for MPH ERCT and IR MPH (MPH ERCT/IR MPH) for area under the analyte concentration versus time curves (AUC) from time zero to the last measurable analyte concentration (AUC0-last) (87.64%; 95% CI, 84.96-90.41) and AUC0-∞ (89.11%; 95% CI, 86.57-91.73) were within the standard 80% to 125% bioequivalence acceptance criteria. Mean Cmax for MPH ERCT and IR MPH was 12.51 ng/mL and 15.57 ng/mL, respectively; mean time to Cmax was 4.16 hours and 6.43 hours, respectively. The mean Cmax of MPH ERCT was 80% of the Cmax of IR MPH due to a higher peak concentration that occurs after the second dose of IR MPH. All adverse events were mild in severity.

Implications: The relative bioavailability of MPH ERCT 40 mg, based on the exposure (AUC), was comparable to that of IR MPH 40 mg administered in 2 equal doses of 20 mg 6 hours apart. Both formulations were generally well tolerated.

Keywords: attention-deficit/hyperactivity disorder; bioavailability; dose forms; methylphenidate; pharmacokinetic properties.