Clinical Response and Safety of Bevacizumab-awwb treatment in Patients with Metastatic Colorectal Cancer: A case series and review of the literature

Abstract

Abstract Background: Bevacizumab-awwb (MVASI®) is the first and the only bevacizumab biosimilar made available in Taiwan. However, its extrapolation of indication and the lack of available real-world clinical data has raised some concern. This article is aimed at presenting our real-world experience in the use of MVASI for treating patients with metastatic Colorectal Cancer (mCRC) for purposes of evaluating tumor response and safety. Materials & Methods: Adult patients from a single institution initiating MVASI use following an mCRC diagnosis during the period of May 2020 to August 2021 were included in the study. Each patient's demographics and tumor characteristics were collated retrospectively. We described treatment patterns and evaluated treatment efficacy stratified by initiating MVASI as either first line or later line therapy. Results: A total of 20 patients were identified, with 2 being excluded due to incomplete therapy and lost follow-up. The mean age of the subjects was 58.7 years. Most patients had a left-sided colorectal tumor (83.3%) and underwent a primary tumor resection (94%) prior to systemic antineoplastic therapy. Fourteen out of 18 patients initiated MVASI use as first line therapy, where the Disease-control Rate (DCR) was 85.7%. Alternatively, four out of 18 patients in later line therapy all experienced disease progression, with progression-free survival (PFS) ranging 4 to 10 months. Five patients had prior bevacizumab reference product utilization but switched to MVASI mostly due to economic issues, with three of these patients (60%) showing progression disease (PFS ranging 3-10 months). Only two patients (11%) encountered adverse events during MVASI therapy. Conclusion: Both the efficacy and safety of MVASI in the mCRC population are deemed comparable with the bevacizumab reference product, exclusively at first line therapy. The strategy of switching between the biosimilar and reference product is currently controversial, and therefore further studies are still required.