Compatibility Studies of Different Crystal Forms of Imatinib Mesylate with Pharmaceutical Excipients

Imatinib mesylate has been identified as a tyrosine kinase inhibitor that selectively inhibits Abl tyrosine kinases, including Bcr-Abl. It exhibits many polymorphic forms, with the most stable and commercialized polymorphs known as the α and β forms. In the present study, the compatibility between the polymorphs of Imatinib mesylate and selected excipients (MCC, HPMC, PVPP, SiO₂, MS, and CaHPO₄) was investigated by differential scanning calorimetry (DSC), Raman spectra, X-ray diffraction (XRD) technique, and isothermal stress testing (IST). The results revealed that polymorph α of Imatinib mesylate has poor compatibility with selected excipients at high temperatures. As a contrary, polymorph β of Imatinib mesylate shows high compatibility with the selected excipients except MS under high temperatures.