The current analysis compared only the OS outcomes for arms B and C. Results of the primary analysis of investigator-assessed progression-free survival (PFS) – a coprimary endpoint of the trial – were reported in 2018 at the annual meeting of the American Society of Clinical Oncology and showed a statistically significant improvement in median PFS in arm B vs. arm C (6.3 vs. 5.6 months; HR, 0.715). The PFS benefit was seen in all PD-L1-positive subgroups.
“This was a very incredible trial, because it was conducted in a group of patients in which we need additional therapies – patients with squamous histology,” Dr. Cappuzzo said during a press briefing at the conference. “IMpower131 is certainly a positive study; we had PFS, as an independent coprimary endpoint, improve significantly, with a meaningful survival difference in the group of patients with strongly positive PD-L1 tumors.
“So these data clearly suggest that [patients with high PD-L1 expression), specifically, may benefit from the combination of chemotherapy and atezolizumab.”
He further noted in a press statement that “the findings provide additional evidence of the efficacy of immunotherapy in patients with lung cancer, and highlight the relevance of biomarkers for patient selection.”
Dr. Cappuzzo reported having no disclosures.
SOURCE: Cappuzzo F et al. WCLC 2019, .