In the phase 2 ECOG-ACRIN EA5161 trial, a significant improvement in both progression-free and overall survival was observed from adding the checkpoint inhibitor nivolumab to chemotherapy (cisplatin/carboplatin with etoposide) as frontline therapy for extensive-stage small cell lung cancer (EC-SLC, researchers reported at the virtual meeting of the American Society of Clinical Oncology.

The ECOG-ACRIN EA5161 trial enrolled 160 patients with measurable (RECIST v1.1) ES-SCLC, who had not received prior systemic treatment for ES-SCL. Patients were randomized 1:1 to nivolumab 360 mg plus  a platinum-based backbone (either cis/carboplatin) with etoposide every 21 days for 4 cycles followed by maintenance nivolumab 240 mg every 2 weeks until progression or up to 2 years, or to cis/carboplatin and etoposide every 21 days for 4 cycles followed by observation. The primary endpoint of this trial was investigator-assessed progression-free survival (PFS). Secondary endpoints included overall survival (OS), objective response rate (ORR), and safety assessments.

“In the nivolumab-plus-chemotherapy arm, the median progression-free survival was 5.5 months versus 4.7 months in the chemotherapy-alone arm. The hazard ratio is 0.68 with a P-value of 0.047.”, reported Prof. Ticiana Leal, University of Wisconsin Carbone Cancer Center, Maddison, USA. In the intention-to-treat population, the PFS in the nivolumab-plus-chemotherapy arm, is 5.5 months versus 4.6 months in the chemotherapy-alone arm (HR: 0.65; 95% CI: 0.46-0.91; P=0.012).

In addition, the median OS was improved by adding nivolumab to chemotherapy: 11.3 months versus 8.5 months (HR: 0.67; 95% CI: 0.46-0.98, P=0.038), as was the ORR (52% versus 47%) and the duration of response (5.6 months versus 3.3 months). The combination of nivolumab and chemotherapy was well tolerated with manageable toxicities.

“In conclusion, this trial confirms the efficacy of the combination of nivolumab and platinum-based chemotherapy in extensive-stage small cell lung cancer”, said Prof. Leal.

 

Leal T, et al. ASCO 2020 virtual meeting, abstract 9000