Synthesis and Biological Evaluation of Antibody Drug Conjugates Based on an Antibody Expression System: Conamax
Zhala Tawfiq, Nicky C. Caiazza, Spiros Kambourakis, Yutaka Matsuda, Benjamin R. Griffin, J. Casey Lippmeier, Brian A. Mendelsohn
Abstract
Antibody production for ADCs (or in general) is commonly performed by CHO-based platforms and limited by volumetric productivity, expensive downstream purification, and extended optimization timelines. The Conamax platform is a novel microbial-based protein production and secretion system. A suite of synthetic biology tools have enabled high volumetric productivity (>1 g/L/d) and glycoengineering to produce simple and consistent human-like post-translational modifications. Conamax can be engineered to secrete genuine, functional monoclonal antibodies that have been successfully used to make antibody drug conjugates (ADCs) via cysteine-linked conjugation. Specifically, we evaluated ADCs derived from both a Conamax-produced anti-HER2 antibody and comparable commercially sourced Chinese hamster ovary (CHO)-produced material in an NCI-N87 gastric cancer xenograft model. Conjugation efficiency and resulting analytical data indicated comparable ADC quality and attributes. No statistical difference was observed between Conamax- and CHO-derived test articles thereby indicating similar efficacy and function. These results further demonstrate the potential of Conamax as a useful platform for the discovery and production of therapeutic antibodies and ADCs.