A phase II study of carboplatin and etoposide plus durvalumab for previously untreated extensive-stage small-cell lung cancer (ES-SCLC) patients with a poor performance status (PS): NEJ045A study protocol.

<bold>Background: </bold>Small-cell lung cancer (SCLC) accounts for 12-15% of lung cancers and has a limited prognosis, with approximately one-third of SCLC patients having a poor performance status (PS). Patients with extensive-stage (ES) SCLC and a poor PS have a poor prognosis. For this population, overall survival from carboplatin and etoposide treatment is 7-8 months, and treatment development is an unmet medical need. Recently, the combination of an anti-PD-L1 (a ligand for programmed cell death 1) antibody and platinum-based chemotherapy has become the standard of care for ES-SCLC patients with a good PS (PS 0-1). We hypothesized that the combination of the anti-PD-L1 antibody durvalumab with carboplatin and etoposide would be feasible and effective for such patients.<bold>Methods: </bold>We initiated a multicenter phase II study of durvalumab combined with carboplatin and etoposide in previously untreated ES-SCLC patients with a poor PS (PS 2-3). Eligible patients will receive durvalumab plus carboplatin and etoposide every 3 to 4 weeks for up to 4 cycles, followed by durvalumab every 4 weeks until progression or unacceptable toxicity. The dosages of carboplatin and etoposide for the second and subsequent cycles will be adaptively determined based on the adverse events of the first cycle. A total of 56 patients (43 patients with a PS of 2 and 13 patients with a PS of 3) will be enrolled in this study, with a 24-month enrollment period and a 12-month follow-up. The primary endpoint is the tolerability of carboplatin and etoposide plus durvalumab in previously untreated ES-SCLC patients with a poor PS. The secondary endpoints are the 1-year survival rate, objective response rate, progression-free survival, overall survival, ratio of PS improvement, and safety.<bold>Discussion: </bold>The results of this study are intended to establish the safety and efficacy of carboplatin and etoposide plus durvalumab in patients with ES-SCLC and a poor PS.<bold>Trial Registration: </bold>Japan Registry of Clinical Trials (jRCT), jRCTs031200319. Registered 21 January 2021, https://jrct.niph.go.jp/en-latest-detail/jRCTs031200319. [ABSTRACT FROM AUTHOR]