An Open-label Randomized Crossover Study with Adaptive Design of the Pharmacokinetics and Bioequivalence of GP30121 and Ceraxon® Corrected for Endogenous Analyte Level

Introduction. Citicoline is an endogenous nucleoside consisting of cytidine and choline linked by a diphosphate bridge that is involved in the synthesis of membrane phospholipids. Drugs containing citicoline have neuroprotective and neurometabolic effects and are used for the treatment of a wide range of neurological disorders. In its turn, bioequivalence study is a pathway to register a generic citicoline drug in Russian Federation.

Aim. The aim of the study was to investigate the comparative pharmacokinetics (PK) and bioequivalence of two citicoline-containing drugs GP30121 and Ceraxon® in healthy male volunteers when taken on an empty stomach.

Materials and methods. We evaluated the pharmacokinetics of citicoline-containing drugs corrected for endogenous analyte (uridine) level using an adaptive design. We determined uridine concentration by high-performance liquid chromatography with mass spectrometric detection. We used R Project software, version 3.6.3. for performing statistical analysis for the study.

Results and discussion. GP30121 and Ceraxon® exhibited similar PK profiles. It was shown that the values of 94.12 % confidence interval (CI) at α = 0.0294 for the geometric mean ratios for the primary PK parameters of the main metabolite of the active ingredient of the investigated drugs were fully contained within the predefined equivalence limits of 80.00–125.00 %.

Conclusion. The study demonstrates bioequivalence of GP30121 and Ceraxon® proving the approach with the correction for endogenous analyte could be considered in studies of other drugs.

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