A single-arm phase II study of platinum doublet induction chemotherapy combined with toripalimab for driver gene-negative advanced NSCLC.

Abstract

e20565 Background: PD-1/PD-L1 inhibitors combined with platinum doublet chemotherapy have become the standard first-line treatment for driver gene-negative advanced non-small cell lung cancer (NSCLC). However, not all patients can benefit from this treatment. Previous studies have shown that induction chemotherapy can reduce tumor burden, induce tumor immunogenic cell death, and improve the tumor immune microenvironment. Therefore, effective induction chemotherapy may enhance the efficacy of PD-1/PD-L1 immunotherapy. This single-arm, phase II clinical trial aims to evaluate the efficacy and safety of induction chemotherapy followed by immunotherapy (Toripalimab: PD-1 inhibitor) in treatment of driver gene-negative advanced NSCLC. Methods: Eligible patients received platinum doublet chemotherapy for 2-4 cycles (pemetrexed + platinum for adenocarcinoma; paclitaxel or gemcitabine + platinum for squamous cell carcinoma). patients who achieved tumor response (CR/PR/SD) received Toripalimab (240mg Q3W) for 2 years or until disease progression or intolerable toxicity. The primary endpoint was progression-free survival (PFS), which was defined as the duration from the initiation of induced chemotherapy to either tumor progression or death from any cause,and the secondary endpoints were toxicity, overall survival (OS), and clinical tumor response including objective response (defined as complete [CR] or partial response [PR]) and disease control (defined as CR, PR, or stable disease [SD]) during the course of combination treatment with Toripalimab following induction chemotherapy. Results: During the period from February 2020 through October 2023, a total of 19 qualified patients were enrolled in the study. As of December 31. 2023,the median follow-up was 22,9 months (range,15.9 to 30 months).11 patients (57.9%) experienced PFS events and 7 (36.8%) died, mOS were not reached. mPFS was 7.9 mo (95% CI,4.8-15.0months).12-month and 18-month PFS rate were 43% and 35%, respectively. One patient has not received tumor response assessment. Among the remaining 18 pts, 10 patients had a PR,5 patients had SD, and 3 patients had PD. The ORR and DCR were 55.6% and 83.3% respectively.42.1% (8/19) pts experienced immune-related adverse events(irAEs), included immune-related pneumonia (21.1%), rash (10.5%), hypothyroidism (10.5%). 2 pts experienced ≥3 grade irAEs, including grade 3 rash and grade 4 immune-related thrombocytopenia. Conclusions: Induction chemotherapy combined with Toripalimab achieved impressive 12-month and 18-month PFS rates in pts with driver gene-negative advanced NSCLC, along with manageable toxicities. These findings demonstrate the potential of induction chemotherapy could enhance the efficacy of immunotherapy. Clinical trial information: NCT04613804 .