Risk Evaluation of N‑Nitrosamines in Drug-Linker Intermediates Used To Generate Antibody–Drug Conjugates

This position study provides a science-based, holistic approach to evaluating the risks of nitrosamine presence in drug-linkers as intermediates toward antibody–drug conjugate (ADC) drug substances. The evaluation of 47 different ADC drug substances, which have a recommended dose available in the public domain, supports the conclusion that the chemically synthesized fragments of ADCs are unlikely to lead to nitrosamine presence in the final drug product. Hence, it can be concluded that for most ADCs there are few nitrosamine risks introduced by the drug-linkers and their impurities. An abbreviated workflow for quality risk management of nitrosamine in drug-linkers is therefore proposed.