Post-Translational Modifications in Protein Therapeutics: Importance and Analytical Tools
Emily E F Fekete1, Huixin Lu1, Xu Zhang2
1Biologic and Radiopharmaceutical Drugs Directorate, Health Products and Food Branch, Health Canada, Ottawa, ON, Canada.
Methods in Molecular Biology (Clifton, N.J.)
|August 1, 2026
Summary
Post-translational modifications (PTMs) are crucial for biologic drug quality. Understanding and analyzing PTMs using various techniques ensures the development of safe and effective protein-based therapeutics.
Area of Science:
- Biochemistry
- Biopharmaceutical Science
- Analytical Chemistry
Background:
- Post-translational modifications (PTMs) significantly impact protein function, stability, and therapeutic efficacy.
- PTMs are critical quality attributes (CQAs) in protein- and cell-based biologic drug development.
- Accurate characterization of PTMs is essential for ensuring the safety and effectiveness of biologic medicines.
Purpose of the Study:
- To provide an overview of PTMs relevant to therapeutic proteins.
- To review common and emerging analytical techniques for PTM characterization in biopharmaceuticals.
- To highlight the importance of PTM analysis in biopharmaceutical product development.
Main Methods:
- Literature review of PTMs in therapeutic proteins.
- Survey of analytical methodologies for PTM detection and characterization.
- Discussion of PTMs as critical quality attributes.
Main Results:
- PTMs encompass a wide range of modifications affecting protein structure and function.
- Diverse analytical techniques, including mass spectrometry and chromatography, are employed for PTM analysis.
- Characterization of PTMs is integral to the quality control of biologic therapeutics.
Conclusions:
- Comprehensive understanding and analysis of PTMs are vital for the successful development of biologic drugs.
- Advancements in analytical technologies enhance the ability to characterize PTMs.
- Effective PTM characterization contributes to the delivery of safe and reliable biologic medicines.
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