Gilead Sciences (GILD.US) partners with Tubulis to develop antibody-drug conjugates targeting solid tumors

Gilead Sciences (GILD.US) and Tubulis today announced that they have entered into an exclusive option and license agreement to collaborate on the discovery and development of antibody drug conjugates (ADCs) targeting solid tumor targets. Under the agreement, Gilead will gain access to Tubulis' proprietary technology platforms, Tubutecan and Alco5.

Tubulis will lead the candidate drug discovery and development efforts, designing an ADC candidate based on a topoisomerase I inhibitor. The drug will have superior biophysical properties and stability, aiming to address current treatment challenges such as insufficient efficacy duration and non-targeted toxicity.

Tubulis aims to address the major bottlenecks in ADC development by innovating in all aspects of ADC development to maximize overall ADC performance. The company's platform allows for the use of payload classes beyond traditional ones, and through novel chemical linkers, expands the conjugation options between antibodies and payloads to achieve stable high drug-to-antibody ratios (DARs).

In March this year, the company completed a B2 round of financing of nearly $140 million, which will primarily be used to support Tubulis' next-generation ADC clinical development and help achieve clinical proof-of-concept for its lead candidates TUB-040 and TUB-030. TUB-040 targets Napi2b, a target that has been extensively characterized in ovarian and lung cancers, while TUB-030 targets 5T4, an antigen that is frequently overexpressed in solid tumors. The preclinical proof-of-concept data for both candidates were presented at the AACR annual meeting in April.

The agreement terms include a $20 million upfront payment to Tubulis; an additional $30 million option fee if Gilead exercises its option; and potential development and commercialization milestone payments of up to $415 million. Tubulis will be responsible for the early research and development of the ADC project. If Gilead exercises its exclusive license, it will be responsible for the subsequent development and commercialization of all products resulting from the collaboration.