Phase II Study of Maintenance Pembrolizumab in Patients with Extensive-Stage Small Cell Lung Cancer (SCLC)

摘要: Abstract Objective The aim of this study was to assess the efficacy maintenance pembrolizumab in patients with extensive-stage SCLC after treatment platinum and etoposide. Methods Patients a response or stable disease induction chemotherapy were eligible. Pembrolizumab at dose 200 mg administered intravenously every 3 weeks initiated within 8 last cycle chemotherapy. primary end point progression-free survival (PFS) from registration, overall (OS) as key secondary point. Available tumor tissue assessed for expression programmed death ligand 1 (PD-L1) both cells surrounding stroma. Blood circulating collected before first, second, third cycles pembrolizumab. Results Of 45 enrolled, 56% male 22% had treated brain metastases. median PFS 1.4 months (95% confidence interval [CI]: 1.3–2.8), 1-year 13%. OS 9.6 CI: 7.0–12), 37%. 30 tumors that could be assessed, three PD-L1 (≥1%) cells. A total 20 eight positive stromal interface 6.5 1.1–12.8) compared 1.3 0.6–2.5) 12 negative marker. No unexpected toxicities observed. Conclusion Maintenance did not appear to improve historical data. However, rate 13% 37% suggest subset benefit