Arcus Biosciences has revealed positive Phase II results for its Gilead-partnered anti-TIGIT drug candidate domvanalimab as a first-line treatment for metastatic, PD-L1-high non-small cell lung cancer (NSCLC).

The three-arm ARC-7 study is evaluating the safety and efficacy of domvanalimab plus anti-PD1 antibody zimberelimab versus zimberelimab alone versus domvanalimab plus zimberelimab and etrumadenant.

According to Arcus, both arms with domvanalimab-based combinations showed encouraging clinical activity – as measured by overall response rate (ORR).

The zimberelimab monotherapy arm showed activity similar to that of marketed anti-PD-1 antibodies studied by other companies in this setting, Arcus said in a statement.

No unexpected safety signals were observed at the time of data cut off, with the current safety profile for each arm appearing to be consistent with known immune checkpoint inhibitors in this setting.

Gilead has an exclusive option to co-develop and co-commercialise domvanalimab and is expected to make a decision regarding opting into the anti-TIGIT programme later this year.

The two companies will continue to prepare for additional Phase III studies of domvanalimab-based combinations and also explore development plans for combinations including the anti-TIGIT candidate and etrumadenant, a dual A2a/A2b adenosine receptor antagonist.

The three arms of the ARC-7 trial and the ongoing ARC-10 Phase III registrational studies are continuing to enrol ‘as planned’, with data from ARC-7 to be submitted later this year for presentation at a medical conference.

“This analysis of the dataset for the ongoing ARC-7 study revealed encouraging clinical activity for the anti-TIGIT domvanalimab-based combinations, and furthermore, that the anti-PD-1 zimberelimab monotherapy arm showed activity similar to that of marketed anti-PD-1 antibodies studied in this setting,” said Bill Grossman, chief medical officer of Arcus.

“Next steps are to complete enrolment in all our open domvanalimab studies, execute on our broader plans for Phase III studies for domvanalimab across multiple cancer types, and further explore combinations with domvanalimab and etrumadenant,” he added.