FOSTER CITY, Calif. — Gilead Sciences Inc. has completed its acquisition of Tubulis GmbH, adding a Germany-based clinical-stage biotechnology company focused on next-generation antibody-drug conjugates to its oncology portfolio.
The deal gives Gilead access to Tubulis’ ADC assets and technology platform, which is designed to deliver diverse cancer-fighting payloads more selectively to tumors. Gilead said the platform is intended to support the development of ADCs with improved biophysical properties and strong on-tumor payload exposure.
Tubulis’ lead asset, TUB-040, is a NaPi2b-directed topoisomerase-I inhibitor ADC that has shown promising activity in platinum-resistant ovarian cancer. The acquisition also adds TUB-030, a 5T4-directed ADC being studied across multiple solid tumor types.
“We look forward to welcoming the Tubulis team to Gilead and building on the significant progress they have made in advancing novel ADC technology for people living with cancer,” said Daniel O’Day, Chairman and Chief Executive Officer, Gilead Sciences. “Our two-year collaboration with Tubulis gave us strong conviction in their team, their programs and their technologies. We will now combine our strengths in service of providing new options for some of the most challenging forms of disease.”
Gilead acquired all outstanding equity of Tubulis for $3.15 billion upfront on a cash-free, debt-free basis, with up to $1.85 billion in potential milestone payments.
Tubulis’ team will remain based in Munich, Germany, where Gilead is establishing the Tubulis ADC Innovation Center. The center will focus on advancing next-generation ADCs by building on Tubulis’ discovery, manufacturing and clinical development capabilities.
TUB-040 targets NaPi2b, a protein expressed at high levels in several tumor types, including ovarian, lung and endometrial cancers. The therapy uses Tubulis’ Tubutecan technology, which is engineered to attach eight topoisomerase-I inhibitor chemotherapy payloads to a stable, cleavable linker system.
Gilead said the design is intended to deliver the drug directly to cancer cells while limiting exposure to healthy tissue, potentially improving tolerability compared with earlier ADC technologies.
In early clinical studies, TUB-040 showed encouraging anti-tumor activity and a manageable safety profile in patients with platinum-resistant ovarian cancer, according to data reported at ESMO 2025. The therapy is currently being evaluated in an ongoing multicenter Phase I/IIa study in patients with platinum-resistant ovarian cancer and relapsed or refractory non-small cell lung cancer.
