Durvalumab and chemotherapy in extensive stage small cell lung cancer showed an improved overall survival compared to chemotherapy alone.
Small cell lung cancer (SCLC) is an aggressive high-grade neuroendocrine malignancy with a high metastatic potential and is associated with poor clinical outcomes. Patients with extensive-stage small cell lung cancer (ES-SCLC) are normally treated with combination chemotherapy which includes carboplatin or cisplatin plus etoposide.
In 2019 the CASPIAN study was published which compared combination chemotherapy, consisting of etoposide + cisplatin/carboplatin (EP), in treatment-naive patients with ES-SCLC with the addition of either durvalumab or tremelimumab.
The results showed that addition of durvalumab (D + EP) 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.
In a 2020 study update, the manufacturer, AstraZeneca, announced 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).
The latest results for the CASPIAN trial were presented at the ESMO 2021 conference. These show 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, 22.9% vs 13.9% of patients given durvalumab plus chemotherapy were alive at 24 months and 17.6% vs 5.8% of patients were alive at 36 months with D + EP vs EP.
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.