8 April 2021 - - US-based pharmaceutical company Bristol Myers Squibb (NYSE: BMY) has released positive topline results from the Phase 3 CheckMate -648 trial evaluating treatment with Opdivo (nivolumab) plus chemotherapy or Opdivo plus Yervoy (ipilimumab) in patients with unresectable advanced or metastatic esophageal squamous cell carcinoma, the company said.

In the study, Opdivo plus chemotherapy demonstrated a statistically significant and clinically meaningful benefit for the primary and secondary endpoints of overall survival in patients whose tumors express PD-L1 and in the all-randomized patient population at the pre-specified interim analysis.

Additionally, Opdivo plus chemotherapy demonstrated a statistically significant and clinically meaningful improvement in the primary endpoint of progression-free survival by blinded independent central review in patients whose tumors express PD-L1.

Opdivo plus Yervoy also met its primary and secondary endpoints by demonstrating statistically significant and clinically meaningful improvement in overall survival in patients whose tumors express PD-L1 and in the all-randomized population. 

Opdivo plus Yervoy did not meet its other primary endpoint of progression-free survival by BICR in patients whose tumors express PD-L1.

The safety profiles of Opdivo and the combination of Opdivo and Yervoy were consistent with those previously reported.

The data from CheckMate -648 build upon those from CheckMate -649, together making Opdivo the first and only PD-1/L1 inhibitor to demonstrate superior first-line survival in upper GI cancers across histologies and tumor locations (stomach, gastroesophageal junction, and esophagus).

They also add to the existing body of data demonstrating the clinical benefit of Opdivo in esophageal cancer, from the late-line metastatic setting to earlier stages of disease.

The company will complete an evaluation of the CheckMate -648 data and looks forward to sharing the results at an upcoming medical conference, as well as with health authorities. Bristol Myers Squibb thanks the patients and investigators who were involved in the CheckMate -648 clinical trial.

CheckMate -648 is a randomized Phase 3 study evaluating Opdivo plus Yervoy or Opdivo plus fluorouracil and cisplatin against fluorouracil plus cisplatin alone in patients with unresectable advanced or metastatic esophageal squamous cell carcinoma.

The primary endpoints of the trial are overall survival and progression-free survival by blinded independent central review in patients whose tumors express PD-L1, for both Opdivo-based combinations versus chemotherapy.

Secondary endpoints of the trial include overall survival and progression-free survival by BICR in the all-randomized population.

In the Opdivo plus Yervoy arm, patients received treatment with Opdivo 3 mg/kg every 2 weeks and Yervoy 1 mg/kg every 6 weeks up to 24 months or until disease progression or unacceptable toxicity.

In the Opdivo plus chemotherapy arm, patients received treatment with Opdivo 240 mg on Day 1 and Day 15, fluorouracil 800 mg/m²/day on Day 1 through Day 5 (for 5 days), and cisplatin 80 mg/m² on Day 1 of four-week cycle.

Patients received Opdivo for up to 24 months or until disease progression or unacceptable toxicity, and chemotherapy until disease progression or unacceptable toxicity.