Clinical Responses to Tarlatamab Among Patients with Pulmonary Carcinoid.

BACKGROUND: Pulmonary carcinoid (PC) is a rare, well-differentiated neuroendocrine tumor of the lung. In patients with metastatic disease, systemic therapies typically have low response rates, and long-term survival is poor. PC frequently expresses DLL3, but whether it responds to the DLL3-targeted bispecific T-cell engager tarlatamab is unknown. METHODS: We analyzed 11 patients with DLL3-high PC treated with tarlatamab at Memorial Sloan Kettering. Tumor response was assessed using RECIST v 1.1. RESULTS: Response rate was 8/11 (73%), including one patient with central nervous system-only disease, and disease control rate was 11/11 (100%). All patients experienced reduction of their measurable disease. One patient had progressed at time of data cutoff and median progression-free survival was not reached. Cytokine release syndrome (CRS) occurred in cycle 1 in 9/11 (82%) patients including 2 with grade 3 CRS. CONCLUSIONS: Tarlatamab demonstrated a high response rate in PC. Cytokine release syndrome was common. Tarlatamab is a promising treatment option for patients with PC.