Development of analytical method for charge variants determination of biosimilar monoclonal antibodies

Methods: Samples: different batches of Keytruda (pembrolizumab) and Opdivo (nivolumab). Treatment of samples with carboxypeptidase B (CPB) at 25 C for 30 minutes; pI markers: 6.14 (low) and 9.46 (high); System suitability: pI markers 7.05, 7.65 and 8.18; including water blank and CPB control; Three combinations of carriers pharmalytes: Results: Reproducible profiles, comparable to the described for pembrolizumab and nivolumab (GOYON et al., 2017); Resolution enough to clearly identify at least five different variants for each mAb; Most adequate migration obtained with three pharmalytes; Main peaks with pI values 8.3 for pembrolizumab and 8.6 for nivolumab. Conclusion: A cIEF method was developed for determination of charge variants in mAbs.After analytical validation, the proposed method might be used in characterization panel tests for registration submission and quality control of biosimilar mAbs produced by Bio-Manguinhos.