A mid-stage trial of Roche’s MPDL3280A has shown that, compared to the chemotherapy docetaxel, the experimental immunotherapy doubled the likelihood of survival in patients with non-small lung cancer expressing the highest levels of PD-L1.

According to data from the Phase II trial, a survival benefit was also observed for patients with medium and high or any level of PD-L1 expression, as determined by a test being developed by the Swiss drugs giant.

But the study of MPDL3280A clearly showed that “the amount of PD-L1 expressed by a person’s cancer correlated with improvement in survival,” noted Sandra Horning, Roche’s chief medical officer. “The goal of PD-L1 as a biomarker is to identify people most likely to experience improved overall survival with MPDL3280A alone and which people may be appropriate candidates for a combination of medicines,” she added.

On the safety side, the drug was generally well-tolerated, with observations consistent with other NSCLC trials, the firm said, adding that updated results will be presented in an oral session at the 51st Annual Meeting of the American Society of Clinical Oncology (ASCO) later this month.

MPDL3280A was awarded US Breakthrough Therapy Designation earlier this year for the treatment of people whose NSCLC expresses PD-L1 and who progressed during or after standard treatments. Roche is currently testing the drug in three Phase II and six Phase III studies in various kinds of lung cancer.