Bristol-Myers Squibb Co. said an analysis of the phase 1/2 CheckMate -032 trial in patients with a certain type of lung cancer showed that Opdivo alone, or combined with Yervoy, exhibited encouraging response and survival rates.

While the company had already announced objective response rates from the study — 11% for Opdivo alone and 22% for the combination — it conducted a follow-up analysis of 211 patients, or a little over half of the pooled intent-to-treat patient population, with a so-called evaluable tumor mutation burden, or TMB.

This patient population was then divided into subgroups of high, medium and low levels.

Tumor mutation burden is a measurement of mutations carried by tumor cells and is one type of biomarker that may help predict the likelihood a patient responds to immuno-oncology therapies.

Based on the analysis, 21% of the patients with high TMB had an objective response that measures the percentage of patients whose tumors shrank; for those with medium and low-level TMB, the objective response rate was 7% and 5%, respectively.

Furthermore, 46% of those in the Opdivo plus Yervoy arm with high TMB had an objective response, while 16% of those with medium and 22% of those with low levels of TMB had an objective response.

In patients with high TMB who received Opdivo, 35% were alive after one year, while 26% and 22% of patients with medium and low levels of TMB were alive after one year, respectively.

In the combination arm, 62% of the patients with high TMB were alive after one year, while 20% and 23% of patients with medium and low levels of TMB were alive after one year, respectively.