Mato, J. M.; Wong, G. L.; Gooijer, Y.; Safaei, A.

Background/Objectives: The quality and characteristics of approved medicines can vary substantially depending on manufacturing processes and standards within a given country. The aim of the study was to compare the available marketed brands of ademetionine tablets derived from various countries in order to identify potential differences between the different formulations. Methods: We performed comprehensive analyses of the physical, chemical, and dissolution characteristics of different formulations of ademetionine tablets marketed in China, India, Russia, Ukraine, and Uzbekistan, using the originator formulation of Heptral as the reference standard. The formulations were evaluated at initial analysis and after 3 months at 40C/75% relative humidity. Clinical parameters such as ademetionine content, degradation products, S,S-isomer, and water content were assessed using HPLC, and a dissolution profile analysis performed in 2 hours of acid solution followed by 90 minutes in a buffer solution. Results: The Nusam (India) and Ximeixin (China) products were the two products most comparable to the Heptral products. Adenomak (Ukraine), the only food-grade product and only one with the tosylate salt showed the most significant quality variations compared to Heptral including dissolution failure as well as considerable variability between batches. Conclusions: The study highlights the importance of using pharmaceutical-grade ademetionine products to maintain clinical efficacy and ensuring standards are maintained across global markets.