An Integrated NMR Approach for Evaluating Linker-Payload Conjugation with Monoclonal Antibodies

Area of Science:

• Biopharmaceutical analysis
• Structural biology
• Nuclear Magnetic Resonance (NMR) spectroscopy

Background:

• Antibody-drug conjugates (ADCs) integrate monoclonal antibodies (mAbs) with small-molecule drugs for targeted therapy.
• Current ADC characterization often uses disruptive methods like mass spectrometry, limiting analysis in physiological conditions.
• Understanding ADC structure and drug-payload properties is crucial for therapeutic development.

Purpose of the Study:

• To introduce a non-disruptive NMR approach for comprehensive ADC characterization.
• To assess the higher-ordered structure (HOS) of mAbs and ADCs.
• To determine the properties of the linker-payload fragment in ADCs.

Main Methods:

• Utilized a combination of ¹H-¹³C ALSOFAST-HMQC and T₂-edited ¹H CPMG NMR experiments.
• Applied the NMR approach to Trastuzumab (a mAb) and a Remdesivir-derived linker-payload model.
• Focused on obtaining structural fingerprints and higher-ordered structure (HOS) information.

Main Results:

• The NMR method successfully provided a structural fingerprint for both the mAb and the ADC.
• Information regarding the higher-ordered structure (HOS) of the antibody component was obtained.
• Properties of the bound linker-payload fragment were elucidated using the NMR technique.

Conclusions:

• The presented NMR approach offers a non-disruptive method for characterizing ADCs.
• This technique provides valuable insights into both the antibody and the drug-payload components of ADCs.
• The method advances the analytical toolkit for biopharmaceutical research and development.