A way forward for generic development of telmisartan tablets: Integrating critical material attributes and...

This study systematically integrated critical material attributes (CMAs) influencing drug release, focusing on factors such as particle size and excipient composition, and characterization of polymorphic form. As a model compound, a BCS class II drug Telmisartan was selected, and the methodology was evaluated using seven different formulations of Telmisartan through comprehensive analysis. The orthogonal analytical techniques, including chromatography, hot-stage microscopy, NMR spectroscopy, and dissolution testing were employed for evaluating critical quality attributes (CQAs). Systematic efforts were made to develop a biopredictive dissolution method using USP dissolution Apparatus I, II, and IV. Based on the t_max value of telmisartan, a multi-stage dissolution strategy was developed to understand the behaviour of formulation in acidic and neutral pH corresponding to the stomach and duodenum under fasting conditions. After de-formulation experiments, formulations were categorized into different buckets based on the size of API particles(d90 value of 8 ± 2 µm; 12 ± 2 µm and >15 µm), the type of excipients present (functional excipient and non-functional excipients), and the micro-environmental pH of the formulations. A rank-based approach was applied to evaluate a robust framework for understanding the differences between these generic formulations. This approach not only supports comprehensive formulation development through CMA-CQA correlations, but also aligns with regulatory expectations for adopting multi-dissolution methods as in vitro testing in cases of formulation change requirements with a bioequivalence waiver for post-approval formulation changes.