Selection of excipients for the formulation of varenicline tablet cores

Abstract

The active pharmaceutical ingredient (APS) of varenicline is a tartrate with the chemical name 7,8,9,10‑Tetrahydro-6,10‑Methano-6H-pyrazino(2,3‑h) (3)benzazepine (as tartrate). Varenicline free base is an achiral molecule, however varenicline tartrate, which is formed by the reaction of varenicline free base and L-tartaric acid, is optically active and has an absolute counterion configuration of 2R, 3R. At the moment, only the drug Champix, produced by the pharmaceutical company Pfizer, is represented among direct analogues, so the development of a domestic analogue is an urgent topic of research. The purpose is to develop the optimal composition of varenicline tablet cores to create a finished dosage form.