Astellas announced it is walking away from a $1.6 billion research and development collaboration with CytomX after six years, while CytomX reported data from its antibody-drug conjugate varsetatug masetecan (Varseta-M) in late-line metastatic colorectal cancer. Astellas’ decision ends a long-term pact exploring T-cell engaging bispecifics; CytomX’s ADC data, disclosed alongside broader oncology updates, show the company continuing clinical exploration of targeted payload delivery. Separately, regulatory news in the roundup included an FDA label expansion for Cosentyx. The twin developments underline shifting alliance dynamics and the capital- and data-driven pressures on oncology partnerships.