Combined therapy with checkpoint inhibitors is effective

Advances in the treatment of small cell lung cancer have been scarce in recent years. Results of second studies now demonstrate a survival advantage for the combination of chemotherapy with immunotherapy.

For more than 20 years, there was nothing positive to report in small cell lung cancer. That has now changed with the results of two combination trials of chemotherapy with immunotherapy.

The open-label phase III trial randomized 805 therapy-naive patients with large cell small cell lung cancer (ES-SCLC) 1:1. One group received four cycles of etoposide/platinum-based chemotherapy plus 1500 mg durvalumab every 3 weeks, followed by durvalumab every 4 weeks. The second group received up to 6 cycles of etoposide/platinum-based chemotherapy every 3 weeks and prophylactic cranial irradiation at the investigator’s discretion. More than half (56.8%) of patients in the control arm received 6 cycles of therapy. Median overall survival (OS) was 10.3 months in the control arm and increased to 13.0 months with combination therapy. This corresponds to a 27% reduction in the risk of death (HR:0.73; 95% CI, 0.591-0.909; p=0.0047). In addition, numerically fewer patients in the combination group developed new lesions (41.4% vs. 47.2%). PD-L1 expression was low and did not appear to be a predictive biomarker.

The second phase III trial, which was double-blind, randomized, and placebo-controlled, also demonstrated a statistically and clinically significant improvement in OS and progression-free survival with the combination of 1L carboplatin + etoposide plus an additional anti-PD-L1 (Table 1).

Source: European Society for Medical Oncology (ESMO) 2019