Efficacy and Safety of Anlotinib and PD-1/L1 Inhibitors as Maintenance Therapy for Extensive-Stage Small Cell Lung Cancer Patients who Have Achieved Stable-Disease After First-Line Treatment with Chemotherapy and Immunotherapy: A Retrospective Study.

Objective: To develop personalized treatment strategies for maintenance therapy in patients with extensive-stage small cell lung cancer (ES-SCLC).

Materials and methods: We analyzed data from ES-SCLC patients who achieved stable disease (SD) following initial chemotherapy combined with immunotherapy. These patients subsequently received maintenance therapy (MT) with a combination of anlotinib and PD-1/L1 inhibitors. The primary endpoints included progression-free survival (PFS), overall survival (OS), objective response rate (ORR), disease control rate (DCR), and treatment-related adverse events (AEs).

Results: Preliminary findings suggest that this regimen is highly effective, with a median PFS of 6 months and OS of 13.5 months, alongside a DCR exceeding 60%. Subgroup analysis revealed enhanced efficacy in patients with fewer than three metastatic sites and those who experienced hypertension, proteinuria, or hand-foot syndrome during MT. Mechanistic studies showed a notable increase in the proportion of CD8+ T cells in the peripheral blood post-MT, correlating with improved outcomes. These findings imply that the therapeutic effect of MT may be partly due to the direct activation of CD8+ T cells, producing a synergistic anti-tumor response. Despite the prevalence of AEs, AEs were generally manageable, underscoring anlotinib's potential in this context.

Conclusion: The combination of anlotinib and PD-1/L1 inhibitors offers promising efficacy and manageable AEs in MT, making it a viable option for ES-SCLC patients who achieve SD post-initial therapy. These results justify further prospective studies to validate this approach.