CHICAGO – Adding the immune checkpoint inhibitor atezolizumab (Tecentriq) to first-line chemotherapy for squamous non–small cell lung cancer (NSCLC) improves outcomes, according to results of the IMpower131 trial reported at the annual meeting of the American Society of Clinical Oncology.
“Squamous NSCLC remains a very difficult to treat disease, and there have been very limited new treatment options presented to us over the last few decades,” lead study author Robert M. Jotte, MD, PhD, medical director and co-chair, USON Thoracic Committee, Rocky Mountain Cancer Centers in Denver, said in a press briefing. Chemotherapy is still considered standard of care in the first-line setting.
Main results showed that compared with chemotherapy (carboplatin and nab-paclitaxel) alone, the combination of atezolizumab and chemotherapy reduced the risk of progression-free survival events by 29%, prolonging median time to an event by about a month. Findings were similar regardless of the level of PD-L1 positivity, although reduction in events was greatest for patients whose tumors were highly positive.
Median overall survival was about 14 months in each arm, with no significant difference, although results are not yet mature.
“IMpower131 data show that patients with advanced squamous NSCLC benefit more from initial treatment with atezolizumab plus chemotherapy than from chemotherapy alone,” Dr. Jotte summarized. The combination “has a manageable safety profile consistent with known safety risks of the individual therapies, with no new safety signals identified.”
The investigators are continuing to follow overall survival, with the next interim analysis expected to occur later this year. “In the IMpower131 study, patients were not allowed to cross over. However, among patients who were monitored and followed for subsequent therapy, nearly half went on to receive immuno-oncologic therapies beyond the study, so that will likely taint the overall survival curves,” he noted.