ASCO 2019: Interim Results With Neoadjuvant Atezolizumab in Resectable Lung Cancer
Posted: Thursday, June 20, 2019
Although surgery has been the primary therapy for early-stage lung cancer for more than 50 years, new study data showed that some patients with early-stage non–small cell lung cancer (NSCLC) may benefit from the immune checkpoint inhibitor atezolizumab in the neoadjuvant setting. These interim results from an ongoing clinical trial were presented at the 2019 American Society for Clinical Oncology (ASCO) Annual Meeting (Abstract 8503) by David J. Kwiatkowski, MD, PhD, of the Dana Farber Cancer Institute, Boston, and colleagues.
“Atezolizumab in the neoadjuvant setting was well tolerated, and pathological complete response and major pathological response rates are encouraging,” the authors wrote.
The multicenter trial included patients with stages IB to stage IIIB resectable NSCLC. At the cutoff for the interim analysis (September 2018), 101 patients were included; 47 were male and 54 were female, with a median age of 64. After receiving atezolizumab on days 1 and 22, patients underwent resection between days 30 and 50. The primary endpoint was major pathologic response, defined as no more than 10% viable tumor cells in the resection specimen. Secondary endpoints included safety, whether response was correlated with PD-L1 expression, and tumor mutation burden.
A total of 90 patients underwent surgery, and 8 of them were excluded from analysis because they had driver mutations. Of the remaining 82 patients, 19% had a major pathologic response, and 4 (5%) had a pathologic complete response.
Thirty-five patients had PD-L1–positive disease and 26 had PD-L1–negative disease. A greater percentage of PD-L1–positive patients experienced a major pathologic response (29%) than PD-L1–negative patients (8%). The median tumor mutation burden did not differ between patients who had a major pathologic response and those who did not.
Two patients died, but the cause was considered unrelated to treatment. There were 29 grade 3 or 4 adverse events, but just 6% of them were treatment-related. The researchers continue to enroll patients and will further analyze tumor mutation burden and gene-expression signatures.
Disclosure: The study authors’ disclosure information may be found at coi.asco.org.
