Gilead agreed to acquire German ADC specialist Tubulis to expand its antibody-drug conjugate capabilities, with deal terms reaching up to $5 billion. The acquisition includes $3.15 billion upfront and up to $1.85 billion in milestone payments and is expected to close in the second quarter of 2026. Tubulis’ lead candidate, TUB-040, is a NaPi2b-directed topoisomerase I inhibitor ADC in Phase Ib/II (NAPISTAR1-01) for platinum-resistant ovarian cancer and non-small cell lung cancer. Analysts and company statements framed the platform as enabling less toxic payload delivery and broader payload diversity; Tubulis is also expected to operate as a dedicated ADC research organization within Gilead once closed.