Gilead Sciences agreed to acquire German biotech Tubulis in a deal valued at up to $5 billion, expanding Gilead’s antibody–drug conjugate (ADC) pipeline with new linker and payload technologies. The purchase is structured with $3.15 billion upfront and up to $1.85 billion in milestones, and is expected to close in the second quarter of 2026. Tubulis’ lead asset, TUB-040, is a NaPi2b-directed topoisomerase I inhibitor ADC in Phase Ib/II NAPISTAR1-01 (NCT06303505) for platinum-resistant ovarian cancer and non-small cell lung cancer. Tubulis also brings TUB-030, a 5T4-targeted ADC with early clinical signals across multiple solid tumors. The acquisition follows recent Gilead dealmaking and positions Tubulis to operate as a dedicated ADC research organization within Gilead, centered on its Munich site. Investors and analysts will watch whether the platform’s differentiation in selectivity and durability translates into clinical efficacy across tumor types.