Safety and Activity of Tarlatamab Combined with PD-L1 Inhibitors as First-Line Maintenance Therapy in Extensive-Stage Small-Cell Lung Cancer: Insights from the DeLLphi-303 Phase 1b Study

Highlights

• Tarlatamab, a DLL3-targeted bispecific T-cell engager, combined with PD-L1 inhibitors (atezolizumab or durvalumab), shows a manageable safety profile as maintenance therapy post chemo-immunotherapy in extensive-stage SCLC.
• The phase 1b DeLLphi-303 study demonstrated promising median overall survival of 25.3 months, surpassing historical benchmarks for extensive-stage SCLC maintenance therapy.
• Adverse events such as cytokine release syndrome and immune effector cell-associated neurotoxicity were notable but manageable without treatment-related mortality.
• The findings support ongoing phase 3 evaluation and highlight translational potential of targeting DLL3 alongside PD-L1 pathways in SCLC.

Background