Bioequivalence of a Donepezil/Memantine 10/20 mg Fixed-Dose Combination Versus Single-Component Tablets in Healthy Korean Males

Abstract

A fixed-dose combination (FDC) tablet formulation of donepezil/memantine (10/20 mg) was developed to improve medication compliance in patients with Alzheimer's disease (AD). This study compared the pharmacokinetic (PK) characteristics and safety profiles of an FDC formulation (donepezil/memantine [10/20 mg]) and single components (SCs) of donepezil (10 mg) and memantine (20 mg). In a randomized, open-label, single-dose, 2-way crossover study, 24 healthy Korean participants received a single oral dose of FDC in 1 period and an SC of donepezil and memantine in another period. For PK analysis, blood samples were collected up to 240 hours after administration. The geometric mean ratios and their 90% confidence intervals for the main PK parameters (C_max and AUC_last) indicated PK equivalence between the FDC and SC formulations. Regarding the safety profile, all adverse events were mild, with no serious adverse events. These findings support the use of an FDC formulation as a viable alternative to SCs of donepezil and memantine, potentially improving treatment adherence in patients with moderate-to-severe AD.