Raman Spectroscopy for Characterizing Monoclonal Antibody Reduction: A Process Analytical Technology Approach for...

Area of Science:

• Biopharmaceutical Manufacturing
• Process Analytical Technology (PAT)
• Spectroscopy

Background:

• Controlled disulfide bond reduction is crucial for antibody-drug conjugate (ADC) manufacturing, impacting conjugation and drug-to-antibody ratios.
• Current characterization methods like capillary electrophoresis are time-consuming, hindering rapid process development and optimization.
• Raman spectroscopy is explored as a PAT tool to analyze reduction kinetics for faster ADC development.

Purpose of the Study:

• To evaluate Raman spectroscopy for elucidating disulfide bond reduction kinetics in ADC manufacturing.
• To assess the potential of Raman spectroscopy as a PAT tool for accelerating ADC process optimization.
• To compare Raman spectroscopy with traditional offline methods for characterizing reduction processes.

Main Methods:

• Design of Experiments (DoE) approach to study TCEP-mediated reduction of IgG1 antibody.
• Varying TCEP/mAb ratios (5-15) and pH conditions (5.5-7.5) during Raman spectral data collection.
• Utilized Principal Component Analysis (PCA) for kinetic analysis and Partial Least Squares (PLS) regression for quantification against nrCE-SDS.

Main Results:

• PCA effectively captured reduction kinetics, correlating with heavy chain (HC) formation.
• Identified pH-dependent TCEP saturation effects influencing reaction kinetics.
• PLS models successfully predicted HC formation, demonstrating potential for endpoint detection.

Conclusions:

• Raman spectroscopy with chemometric analysis offers valuable insights for ADC process development.
• PCA allows rapid screening of reduction conditions, reducing analytical burden.
• Raman spectroscopy presents potential for real-time online PAT implementation, unlike offline methods.