Bristol-Myers Squibb (BMS) has reported mixed results from the Phase III CheckMate -227 study of Opdivo (nivolumab) in combination with chemotherapy or its other drug, Yervoy (ipilimumab).

CheckMate -227 is a multi-part, open-label clinical trial that compared Opdivo combination to chemotherapy alone in first-line advanced non-small cell lung cancer (NSCLC) patients.

The study’s co-primary endpoints are overall survival (OS) and progression-free survival (PFS).

In Part Ia of the trial, a combination of Opdivo and low-dose Yervoy met the OS endpoint with a superior benefit, compared to chemotherapy, in subjects whose tumours express PD-L1 >1%.

Exploratory analysis of Part Ib, involving patients without PD-L1-expressing tumours, also revealed a survival benefit with the combination.

Findings also showed a safety profile consistent with previous data from first-line NSCLC patients who received a combination of 3mg/kg Opdivo every two weeks and 1mg/kg Yervoy every six weeks.

However, Part II of the CheckMate -227 trial failed to meet the OS endpoint when treated with Opdivo plus chemotherapy, compared to chemotherapy alone, irrespective of the patients’ PD-L1 status.

The median OS was 18.83 months with the combination and 15.57 months in the chemotherapy group. The landmark one-year OS was 67.3% versus 59.2%, respectively.

Exploratory analysis observed the median OS to be 18.27 months for Opdivo plus chemotherapy and 11.96 months for chemotherapy alone.

Investigators did not report any new safety signals.

Bristol-Myers Squibb Oncology Development head Fouad Namouni said: “While this is not the outcome we had hoped for, the Opdivo plus chemotherapy one-year landmark overall survival in the non-squamous population was consistent with the experimental arms in previously-reported trials of IO/chemotherapy combination regimens.”

Merck last month announced positive five-year results from a Phase Ib study of its Keytruda as a single agent in advanced NSCLC.

Over five years, Keytruda demonstrated a 23.2% overall survival (OS) rate in treatment-naïve patients and 15.5% in previously treated subjects.