US-based biopharmaceutical company Gilead Sciences has made amendments to its existing collaboration agreement with oncology-focused biotech company Arcus Biosciences.

Gilead has also made a $320m equity investment in Arcus common stock at $21 per share.

In addition, Gilead Sciences has appointed its chief commercial officer Johanna Mercier to the Arcus Board, which brings Gilead’s total director designees to three.

The amended collaboration also includes governance enhancements that enable simplified decision-making and continued growth of the collaboration.

The equity investment and collaboration amendment are expected to advance the growth of the two companies’ joint development programs across multiple indications.

Gilead Sciences chief medical officer Merdad Parsey said: “This amendment allows Gilead to accelerate the domvanalimab program and enables Arcus to focus on progressing multiple pipeline assets, including both Gilead-optioned and non-optioned programs.

“We look forward to strengthening our collaboration as we explore the collective power of our cross-portfolio combinations to help transform how cancer is treated.”

Gilead and Arcus have restructured their joint development programme for domvanalimab, to focus on advancing the Phase 3 studies in lung cancer and gastrointestinal cancer.

The studies STAR-121 (lung cancer) and STAR-221 (gastrointestinal cancer), are expected to be fully enrolled by year-end.

The companies are also planning to initiate a new registrational Phase 3 lung cancer study, dubbed STAR-131, to evaluate a regimen containing domvanalimab plus zimberelimab.

In addition, the collaboration will discontinue further enrolment in Phase 3 ARC-10 study of domvanalimab plus zimberelimab compared to pembrolizumab monotherapy.

Also, the planned Phase 3 study in pancreatic cancer, evaluating the investigational small molecule CD73 inhibitor quemliclustat, will become an independent study under Arcus.

Domvanalimab, zimberelimab and quemliclustat are investigational molecules, which have not been approved by any regulatory authority for use in any indications.

Arcus CEO Terry Rosen said: “Since the inception of our partnership with Gilead in 2020, the companies have moved increasingly closer in all aspects of our research and development efforts.

“This investment and prioritization enable both companies to leverage their respective strengths and focus on efficiently advancing novel combinations that have the potential to change the landscape of cancer treatment.

“The additional investment by Gilead, which extends our cash runway into 2027, will enable us to fund our Phase 3 studies of quemliclustat in pancreatic cancer and AB521 in kidney cancer, as well as to begin preparation for our first potential product approvals.”