One Standard, Multiple Platforms: ICH Q2(R2) Qualification of Host Cell Protein Analysis by LC–MS/MS

Two labs can analyze the same sample and report different Host Cell Protein (HCP) levels. With ELISA, the total number of HCP (ng/mg) is tied to the antibody reagent. With LC-MS, it is tied to whichever MS quantitation method the lab used. Neither result travels beyond the lab that generated it. 

USP General Chapter <1132.1> Residual Host Cell Protein Measurement in Biopharmaceuticals by Mass Spectrometry helped address the MS quantitation gap by defining HCP quantitation relative to a spiked-in intact protein standard. What the industry lacked was the protein itself: a single, consistently sourced material characterized well enough to serve as a common anchor across expression systems, biopharmaceutical modalities, and MS instrument platforms. 

In this GEN webinar, USP and Alphalyse present the work qualifying beta-lactoglobulin (LACB) as a cross-platform standard for LC-MS/MS HCP analysis. LACB was characterized by intact mass, quantitative peptide mapping, and amino acid analysis, confirming a defined composition, an accurately assigned concentration, and greater than 99% purity. It was then qualified as a spike-in standard per ICH Q2(R2) across three host cell systems—CHO (monoclonal antibodies and recombinant fusion proteins), E. coli (recombinant proteins and vaccine antigens), and HEK293 (viral vectors and gene therapies)—meeting linearity, accuracy, precision, and specificity criteria across more than three orders of magnitude. Key takeaways from the webinar include:

• Why the choice of spike-in standard drives your HCP number as much as your acquisition method does 
• What “well characterized” should mean for a material serving as an anchor across expression systems, modalities, and instrument platforms 
• How to implement <1132.1> quantitation relative to spiked-in protein in your own workflow 
• Where a common standard can change the conversation with regulators on impurity clearance 

A live Q&A session will follow the presentations, offering you a chance to pose questions to our expert panelists.

Produced with support from: