From Variability to Reliability: A New IgG4 Reference Standard for Consistent Characterization

Derrick Zhang

Derrick Zhang is a senior scientist II at the US Pharmacopeia (USP), where he leads the development of strategies and standards supporting the analytical evaluation of monoclonal antibodies (mAbs) and therapeutic proteins, with deep expertise in Host Cell Protein (HCP) analysis and LC-MS proteomics. He brings over a decade of biopharmaceutical experience spanning process development, analytical characterization, and method development across organizations including Adaptive Phage Therapeutics, United Therapeutics, and Meso Scale Diagnostics.

Fengqiang Wang, PhD

Fengqiang Wang, PhD, is a principal scientist and team lead in biologics analytical R&D at Merck & Co., Inc., where he leads strategy and innovation in host‑cell protein (HCP) characterization and advanced analytical control across the biologics portfolio. Since joining Merck in 2011, he has supported key analytical initiatives, including the biochemical characterization of pembrolizumab Fab-arm exchange, the establishment of U.S.-based 2D HCP characterization capability, and the development and implementation of both process-specific and platform HCP ELISA assays supporting multiple clinical and commercial stage programs.

Wang has also led cross-modality efforts spanning biocatalysis residual protein control and HCP measurement in live virus vaccine programs. Most recently, he directed accelerated HCP characterization, assay development, and validation of a process-specific HCP assay for WINREVAIR, enabling the first implementation of process-specific assay prior to BLA filing.  He has co-authored more than twenty publications, delivered numerous invited conference presentations, and served as session or track chair at BEBPA HCP Conference, the Bioprocessing Summit, and AAPS PharmSci360. He is an active contributor to the BioPhorum HCP Workstream and currently serves as vice chair of the USP Bio2 Committee.