An UPLC Method for Determination of Structural Analogues of DM1: the Payload of Trastuzumab Emtansine (T-DM1)

DM1, a derivative of maytansine, is the payload of trastuzumab emtansine (T-DM1). In this work, a new gradient reverse-phase ultra-performance chromatographic (RP-UPLC) method was proposed for analysis of five structural analogues (DM1-2, AP-3, DM1-4D, DM1-3D, and DM1-3L) of DM1. The chromatographic separation was accomplished by using a Waters BEH Phenyl column (50 × 2.1 mm, 1.7 μm), at the wavelength of 252 nm. Validation of the method was carried out according the ICH guidelines in terms of specificity, accuracy, precision, linearity and robustness. The developed method was proved to be convenient and reliable for quantitative determination of the DM1 analogue impurities. It can also be used for the related substances determination in DM1 bulk samples.