Antibody–drug conjugates (ADCs) are rapidly evolving from experimental hybrid molecules into mature, platform-driven therapeutics, with the global market projected to reach $36 billion by 2029. As pipelines expand and molecular designs grow more complex, developers are rethinking how ADCs are designed, characterized, and manufactured. In this episode of Off Script, we spoke with Lonza's Sandro Holzer, PhD, director and head of development bioconjugates, and Anette Sommer, PhD, head of bioconjugates research, about how the ADC field has changed over the last several years and what is driving the next wave of innovation.

The conversation explores the industry’s shift toward standardized linker–payload platforms, site-specific conjugation, higher drug-to-antibody ratios, and emerging dual-payload ADCs aimed at overcoming tumor heterogeneity and drug resistance. Holzer and Sommer discuss how rising molecular complexity is reshaping CMC strategy, analytics, and downstream processing, and why early integration of biology, chemistry, and manufacturability is essential to de-risk development and enable scale-up. The episode also examines how ADC manufacturing paradigms are now informing adjacent bioconjugate modalities signaling a broader move toward integrated, multi-component therapeutics beyond oncology.