A Highly Efficient Workflow for Detecting and Identifying Sequence Variants in Therapeutic Proteins with a High
Lance Cadang1, Chi Yan Janet Tam1, Benjamin Nathan Moore1
1Pharma Technical Development, Genentech, South San Francisco, CA 94080, USA.
Molecules (Basel, Switzerland)
|April 28, 2023
Summary
A new mass spectrometry (MS) workflow significantly improves sequence variant analysis (SVA) for protein therapeutics. This method reduces false positives by 93% and turnaround time to two weeks, matching Next-Generation Sequencing (NGS) speed.
Area of Science:
- Biopharmaceutical Manufacturing
- Analytical Chemistry
- Proteomics
Background:
- Large molecule protein therapeutics are crucial in modern medicine, manufactured via cell culture.
- Sequence variants (SVs) are critical impurities arising during biomanufacturing, potentially impacting therapeutic safety and efficacy.
- Current detection methods include genetic screening (e.g., Next-Generation Sequencing - NGS) and mass spectrometry (MS), each with limitations.
Purpose of the Study:
- To develop a highly efficient and rapid Sequence Variant Analysis (SVA) workflow using high-resolution mass spectrometry (MS).
- To optimize MS/MS parameters and software for accurate SV identification and quantitation, reducing time and cost.
- To establish LC-MS/MS as a competitive alternative to NGS for SV detection.
Main Methods:
- Development and optimization of a high-resolution tandem MS and LC-MS/MS SVA workflow.
- Utilized improved software for SV identification and quantitation, including optimization of score cutoffs.
- Investigated and mitigated a specific instrument feature (Fusion Lumos) causing peptide under-quantitation.
Main Results:
- Reduced false positive SVs by up to 93% compared to previous MS workflows.
- Shortened the SVA turnaround time using LC-MS/MS to two weeks, comparable to NGS.
- Demonstrated comparable quantitation values across different Orbitrap platforms.
Conclusions:
- The optimized high-resolution MS/MS workflow provides a rapid, accurate, and cost-effective method for Sequence Variant Analysis.
- This enhanced LC-MS/MS workflow rivals NGS in speed and offers the advantage of detecting non-genetic SVs.
- The developed workflow positions LC-MS/MS as a preferred method for biopharmaceutical sequence variant analysis.
Keywords:
LC-MS/MShigh-resolutionmass spectrometryminor variantspeptide mappingprotein therapeuticssequence variant analysissequence variants

