The study showed that using tumor mutation burden (TMB) can be beneficial for predicting patient response to the combination of 2 immuno-oncology therapies.
Bristol Myers-Squibb has announced results that show patients with early-stage lung cancer had a more favorable treatment response to nivolumab (Opdivo) and ipilumumab (Yervoy) in combination than nivolumab alone. The announcement also includes the first report of tumor mutation burden (TMB) being used as a potential predictive biomarker for 2 immuno-oncology (I-O) agents in combination.
The company announced that data from the CheckMate -32 trial showed patients with previously treated small cell lung cancer that had tumors evaluable for TMB responded positively to both nivolumab and to the nivolumab=ipilumumab combination..
“These exploratory TMB data from CheckMate -032 are the first to show the potentional of using mutation burden to predict response in some patients with the combination of 2 I-O agents,” said Matthew D. Hellmann, MD, study investigator, Memorial Sloan Kettering Cancer Center, in a statement.
As cancer progresses, mutations that are not seen in normal cells of the body accumulate. TMB is the measurement of the quantity of mutations carried by tumor cells. Nivolumab is a programmed death-1 immune checkpoint inhibitor designed to work with the body’s immune system to stop the spread and growth of cancer cells.
Phase 1 and 2 of the CheckMate -32 trial showed that the overall response rate with nivolumab was 21%, while the overall response rate to the I-O combination was more than double that (46%) in patients with high TMB.
For patients with high TMB the overall survival rate of those treated with nivolumab at one year was 35%, and the overall survival rate of patients treated with the I-O combination was 62%.
Patients with medium TMB who were treated with nivolumab had an objective response rate of 7% and patients with low TMB had an objective response rate of 5%.
Patients with medium TMB who were treated with nivolumab plus ipilumumab had an objective response rate of 16% and patients with low TMB had an objective rate of 22%.
At 1 year, 26% of patients with medium TMB being treated with nivolumab were alive, and 22% with low TMB were alive.
For patients who received the I-O combination, 20% of those with medium TMB were alive at one year, and 23% of those with low TMB were alive at 1 year.
“Assessing the effect of TMB on treatment outcomes has been an important part of our ongoing translational medicine research,” said Nick Botwood, MD, development lead, thoracic cancers, Bristol-Myers Squibb, in a statement. “We are committed to our ongoing thoracic cancer development program, focused on identifying patients most likely to benefit from immunotherapy.”