Related Substances Method Development and Validation of Axitinib, Zanubrutinib and Upadacitinib Using RP-HPLC and its Degradation Products were Characterized by Using LC-MS/MS

Background: Axitinib was used to treat carcinoma of renal cells and Upadacitinib was used to treat rheumatoid arthritis and Zanubrutinib used as an anti cancer medication for mantle cell lymphoma. In the current application, Zanubrutinib, Upadacitinib and Axitinib and their associated substances will be developed and validated. Materials and Methods: The optimised method includes the Zanubrutinib, Upadacitinib and Axitinib gradient elution and associated flow rates with dimensions of 1 mL/min and phenyl column X-bridge (150 x 4.6 mm, 3.5 μ). A mobile phase was employed with 1.2 g of Hexane sulphonic acid of pH-2.5 adjusted with ortho-phosphoric acid (buffer) and acetonitrile. Zanubrutinib, Upadacitinib and Axitinib were separated from their associated substances for a total run time of 60 min. The approach developed has been validated in accordance with the ICH guidelines. Results: The test concentration LOD and LOQ were established for both drugs and for their impurities. The diagrams that were drawn were straightforward with an R² regression coefficient > 0.999. As part of the method validation, recovery, specificity, linearity, accuracy, robustness was determined and the results were found to be within an acceptable range. Conclusion: HPLC was used to validate the method in terms of accuracy, linearity, method precision, accuracy, limit of detection, limit of quantification, robustness, and degradation, and LC-MS/MS was used to characterise the degradation products. The system was validated in all of these aspects.