A Comprehensive Approach for HCP Identification , Quantification , and Monitoring Based on a Single Dimension ( 1 D ) LC Separation

■ ■ Progenesis QI for Proteomics software performs accurate HCP identification, quantification, and tracking INTRODUCTION Residual host cell proteins (HCPs) are low-level (1–100 ppm) process-related impurities that might be present in protein biopharmaceuticals even after extensive purification. HCPs could produce unwanted immunogenic responses in patients, they can reduce the efficacy or the stability of the drug, or they can be responsible for drug degradation. For these reasons, the regulatory agencies required that HCPs are identified and quantified prior to drug approval. The biopharmaceutical industry relies on ELISA assays for measuring the total HCP concentration expressed in ppm (or ng HCPs/mg biopharmaceutical). Mass spectrometry based HCP analysis has emerged in recent years as a powerful alternative to ELISA because it provides more extensive (proteomewide) HCP coverage and is able to measure individual HCP levels.1-3