Epacadostat and Pembrolizumab Combo Active in Relapsed NSCLC

Updated efficacy and safety data from the ECHO-202/KEYNOTE-037 study of pembrolizumab plus the IDO1 inhibitor epacadostat showed that the combination therapy had antitumor activity with a tolerable safety profile in patients with relapsed/refractory non-small cell lung cancer (NSCLC), according to data presented at the IASLC’s 19th World Conference on Lung Cancer in Toronto, Canada.¹

The NSCLC cohort of the open-label, single-arm, phase 1/2 ECHO-202/KEYNOTE-037 trial included 70 patients with NSCLC previously treated with platinum-based chemotherapy who had no prior exposure to immune checkpoint inhibitors. Patients with EGFR mutations and those who were intolerant to EGFR inhibitors were included in the cohort.

Patients received 25 mg, 50 mg, 100 mg, or 300 mg twice daily of epacadostat plus 200 mg of pembrolizumab every 3 weeks during phase 1; patients received 100 mg of epacadostat twice daily plus 200 mg of pembrolizumab every 3 weeks during phase 2. The maximum tolerated dose was not reached.

At baseline, the median age was 63; 57% of participants were female; and 76% had a history of smoking. EGFR and KRAS mutations were present in 10% and 19% of patients, respectively. Adenocarcinoma was present in 70% of patients.

The objective response rate was 29%, and remained similar regardless of high PD-L1 or IDO1 expression. The disease control rate was 50% and 10 out of 20 responses were ongoing at data cutoff on January 8, 2018.

The median progression-free survival (PFS) was 4 months (95% CI, 2.1-6.2 months) with 6-, 12-, and 18-month PFS rates of 43%, 31%, and 17%, respectively. Overall survival was not reported.

During the study, 27% of patients experienced grade 3 or higher treatment-related adverse events, which resulted in treatment discontinuation by 3 patients. There were no treatment-related deaths.

According to the investigators, the pembrolizumab and epacadostat combination was “generally well tolerated and associated with promising responses in patients with NSCLC.”

Read more of Cancer Therapy Advisor‘s coverage of the IASLC 2018 meeting by visiting the conference page.

Reference

1. Villaruz L, Schneider B, Bauer T, et al. Epacadostat plus pembrolizumab in patients with non-small cell lung cancer: phase 1/2 results from ECHO202/KEYNOTE-037. Presented at: International Association for the Study of Lung Cancer 19th World Conference on Lung Cancer; September 23-26, 2018; Toronto, Canada. Abstract OA05.02.