Addition of durvalumab to chemotherapy in extensive stage small cell lung cancer improved overall survival compared to chemotherapy alone.
Small cell lung cancer (SCLC) has a high metastatic potential and is associated with poor clinical outcomes. In those where the disease has spread, i.e., extensive-stage small cell lung cancer (ES-SCLC), standard treatment involves combination chemotherapy with carboplatin or cisplatin plus etoposide.
However, in 2019, results of the CASPIAN study demonstrated that addition of durvalumab to combination chemotherapy, with etoposide + cisplatin/carboplatin (EP), in treatment-naive patients with ES-SCLC, led to a 27% reduction in the risk of death (Hazard ratio, HR = 0.73, 95% CI 0.59-0.91; p=0.0047) compared to chemotherapy alone.
This benefit was maintained as reported in a 2020 study update from the manufacturer, AstraZeneca, showing that after two years of follow-up, durvalumab (brand name Imfinzi), maintained a 25% reduction in the risk of death versus chemotherapy alone (HR of 0.75; 95% CI 0.62, 0.91; nominal p=0.0032).
At the ESMO 2021 conference, the latest results for the CASPIAN trial were presented. The data showed that after a median follow-up of 39.4 months, durvalumab and EP continued to maintain a 29% survival benefit (HR = 0.71, 95% CI 0.60–0.86; nominal p=0.0003) over chemotherapy. In terms of survival, there was a huge benefit from durvalumab plus chemotherapy, with 17.6% vs 5.8% (D + EP vs EP) of patients still alive at 36 months.
The incidence of serious adverse events was broadly similar at 32.5%, and 36.5% for durvalumab and EP and EP alone respectively. Adverse events leading to death occurred 5.3%, and 6.0% (D +EP vs ES alone).
Given the overall survival benefit, the authors of the abstract concluded that their data further established D + EP as standard of care for the first-line treatment of ES-SCLC.