Gilead Sciences has agreed to acquire German biotech Tubulis for $3.15 billion upfront, with total consideration of up to $5 billion, as the company steps up its antibody-drug conjugate (ADC) buildout. The deal adds Tubulis’ conjugation, linker and payload technologies, plus clinical candidates including the NaPi2b-directed topoisomerase-I inhibitor ADC TUB-040 and the 5T4-targeting ADC TUB-030. Tubulis’ lead asset TUB-040 is in the Phase Ib/II NAPISTAR1-01 trial (NCT06303505) for platinum-resistant ovarian cancer and non-small cell lung cancer, and received FDA fast-track designation in June 2024. Gilead said Tubulis will operate as a dedicated ADC research organization after closing, with the Munich site positioned as a hub for innovation, manufacturing and clinical development. The acquisition follows Gilead’s earlier 2026 purchases of Arcellx and Ouro Medicines, extending the company’s pattern of frontloading oncology platform bets. In parallel, industry watchers are looking at how Gilead will integrate Tubulis’ technology stack into a broader ADC pipeline strategy, including potential applications beyond oncology. A second report on the same transaction emphasized the deal’s structure—$3.15 billion cash and up to $1.85 billion in milestones—and highlighted that the platform is designed to reduce off-target toxicity while widening payload diversity.