Bioequivalence Study of a Sustained Release Fixed Dose Combination Capsule Containing Esomeprazole and Domperidone in Healthy Subjects

Abstract Objective: The study was designed to determine the relative bioavailability of two sustained release fixed dose combination (FDC) products of two manufacturers containing esomeprazole (CAS 326602-80-6) 40 mg and domperidone (CAS 57808-66-9) 30 mg in 24 healthy male volunteers. The pharmacokinetics of esomeprazole and domperidone individually after oral administration of tablet formulation has been extensively evaluated in adult volunteers. However, no published data are available regarding the combined pharmacokinetics and bioavailability of this particular FDC. Method: The study was designed as a randomized, balanced, open-label, 2-period cross-over study. Each subject was randomized at the beginning of the study to receive either a single dose of the Test FDC or Reference FDC during Period I. Following a 7-day wash-out period, all subjects received the alternate formulation during Period II. Results: No statistically significant differences were obtained between the two products with respect to the mean concentration-time profiles or in the pharmacokinetic parameters, including area under the serum concentration-time curve from the present study. The relative extent of absorption as assessed by the AUC ratio (Test/Reference) and Cmax, the average value was found to be 1.00 ± .09 with 90% confidence limits (C.L.) of 0.82−1.18. Conclusion: These findings clearly indicate that the two products are bioequivalent in terms of rate and extent of drug absorption. Both preparations were well tolerated with no adverse reactions throughout the study.