After Disappointing Bladder Cancer Data, Gilead Announces Encouraging Data From Gastric, Colorectal Cancer Studies

On Saturday, Gilead Sciences Inc GILD and Arcus Biosciences Inc RCUS released longer-term efficacy and safety results from Arm A1 of the Phase 2 EDGE-Gastric study.

The updated data show consistent objective response rate (ORR) and provide mature progression-free survival (PFS) in patients with a locally advanced unresectable or metastatic gastric, gastroesophageal junction or esophageal adenocarcinoma (upper GI cancers).

Related: Gilead’s Trodelvy Fails To Hit Primary Goal In Late-Stage Study With Most Common Type Of Bladder Cancer.

The ongoing, multi-arm, global Phase 2 EDGE-Gastric study is evaluating the safety and efficacy of various combinations of the Fc-silent anti-TIGIT antibody domvanalimab plus the anti-PD-1 monoclonal antibody zimberelimab and chemotherapy in this patient population.

At the data cutoff (March 12, 2024), safety and efficacy were evaluated in all patients enrolled and treated (n=41).

With a median treatment time of 49.4 weeks, the domvanalimab plus zimberelimab and chemotherapy regimen demonstrated sustained improvement across efficacy measures, including in patients with low PD-L1 expression.

The median progression-free survival (PFS) was 12.9 months for the overall population in the trial, with 13.8 months in patients with high PD-L1 expression and 11.3 months in patients with low PD-L1 expression.

12-month PFS rates were 57.6% vs. 68.8% vs. 46.8%.

The confirmed Objective Response Rate (ORR) was 58.5% for overall trial patients, with 68.8% and 50.0% in high and low PD-L1 expression, respectively.

No unexpected safety signals were observed. The domvanalimab plus zimberelimab and chemotherapy regimen was generally well tolerated.

The updated data from Arm A1 of the Phase 2 EDGE-Gastric study support the ongoing Phase 3 STAR-221 study, in unresectable or metastatic upper GI cancers, which is expected to complete enrollment mid-year 2024.

Concurrently, Gilead Sciences and Arcus Biosciences announced new data from Cohort B of ARC-9 Phase 1b/2 study of etrumadenant plus zimberelimab, FOLFOX chemotherapy and bevacizumab (EZFB) in third-line metastatic colorectal cancer (mCRC).

The etrumadenant combo regime significantly reduced the risk of death by 63% and the risk of disease progression by 73% compared to regorafenib.

The median overall survival was 19.7 months in the EZFB regime arm and 9.5 months in the regorafenib arm. The median PFS was 6.2 months vs. 2.1 months.

The confirmed ORR was observed as 17.3% vs. 2.7%.

The EZFB regimen had a safety profile consistent with the known safety profiles of each individual molecule to date, without unexpected toxicities.

Price Action: At last check on Monday, GILD shares were down 1.24% at $63.47, and RCUS shares were up 7.90% at $16.26.