The U.S. Food and Drug Administration (FDA) has accepted Genentech’s Biologics License Application (BLA) and granted Priority Review for the company’s product atezolizumab for the treatment of locally advanced or metastatic non-small cell lung cancer (NSCLC) that expresses the protein PD-L1 in patients who have progressed after platinum-containing chemotherapy.

Atezolizumab is a fully humanized monoclonal antibody designed to bind to programmed death ligand-1 (PD-L1) protein expressed on tumor cells and tumor-infiltrating immune cells, blocking its interactions with PD-1 and B7.1 receptors. Inhibition of PD-L1 possibly leads to an improved activation of immune T-cells and enhancement of the immune response.

The drug, under investigation by Genentech/Roche, is being tested in a series of clinical trials being conducted in several types of cancers, including some currently recruiting for clinical studies in lung cancer.

In February 2015, atezolizumab was granted Breakthrough Therapy designation by the FDA, which is aimed at expediting the development and review of certain medicines to make it accessible as quickly as possible to patients in need. The FDA designation was for the treatment of people whose NSCLC expresses PD-L1 and whose disease progressed during or after standard treatments, such as platinum-based chemotherapy and targeted therapy for EGFR mutation-positive or ALK-positive disease.

The recently announced BLA submission was based on the results from the Phase 2 BIRCH clinical trial (NCT02031458), which evaluated the safety and efficacy of atezolizumab in 667 people with locally advanced or metastatic PD-L1-positive NSCLC.

“In a study of atezolizumab in people with previously treated advanced lung cancer, PD-L1 expression correlated with how well they responded to the medicine,” said Sandra Horning, M.D., chief medical officer and head of Global Product Development at Genentech, in a press release. “The goal of PD-L1 as a biomarker is to identify people most likely to benefit from atezolizumab alone.”

Last month, the FDA also accepted Genentech’s BLA and granted Priority Review for atezolizumab for the treatment of people with locally advanced or metastatic urothelial carcinoma.