e20150 Background: Tarlatamab is a standard second-line treatment for extensive-stage small cell lung cancer (ES-SCLC); however, real-world outcome data remain limited. Methods: We conducted a single-center retrospective study at Ellis Fischel Cancer Center, University of Missouri. Adults with ES-SCLC who received prior platinum-based therapy and ≥1 full dose of tarlatamab between May 1, 2024, and December 1, 2025, were included. Efficacy endpoints included objective response rate (ORR), disease control rate (DCR), real-world progression-free survival (rwPFS), overall survival (OS), and intracranial PFS (IC-PFS). Safety endpoints included cytokine release syndrome (CRS), immune effector cell–associated neurotoxicity syndrome (ICANS), and other treatment-related adverse events (TRAEs). Exploratory analyses included subgroup DCRs and post-tarlatamab treatment patterns. Results: Twenty patients were included. Median follow-up was 193 days, and median age was 63 years. At baseline, 70% had brain metastases, 35% had liver metastases, and 30% had received ≥3 prior lines; 30% were platinum-sensitive, and 35% had prior lurbinectedin. The ORR was 30%, and DCR was 40%. Median rwPFS was 90 days (95% CI, 66–NE); median OS was 396 days (95% CI, 113–NE); and median IC-PFS was 71 days (95% CI, 62–NE). Median IC-PFS was 86 days (95% CI, 53–NE) in patients without baseline brain metastases and 71 days (95% CI, 62–NE) in those with baseline brain metastases. CRS occurred in 20% (all grade 1–2), and ICANS in 10% (one grade 1, one grade 3), with median onset times of 12 and 9.5 hours. Steroids, tocilizumab, and ICU admission were required in 25%, 10%, and 10%, respectively. Median cycle 1 hospital stay was 2 days. Other TRAEs included anemia (5%), lymphopenia (10%), hypoalbuminemia (10%), dysgeusia (20%), and one grade ≥3 transaminitis. Subgroup DCRs were 42.9% vs 38.5% (platinum-sensitive vs -resistant), 20.0% vs 46.7% (bulky vs non-bulky), 42.9% vs 33.3% (brain metastases vs none), 28.6% vs 46.2% (liver metastases vs none), and 20.0% vs 46.7% (CRS/ICANS vs none). Of 11 patients who progressed on tarlatamab, only 3 received subsequent systemic therapy (lurbinectedin, n = 2; platinum, n = 1), with treatment durations of 43–104 days. Conclusions: In this single-center real-world cohort, tarlatamab demonstrated safety and efficacy generally consistent with the DeLLphi-304 trial, with lower CRS rates. Few patients received subsequent systemic therapy, highlighting limited post-tarlatamab options. Exploratory subgroup findings suggest potential heterogeneity in treatment response by metastatic pattern and treatment-related toxicity, warranting further investigation. Lastly, most of our patients are suburban and rural patients, emphasizing collaboration with local community oncologists to provide access to tarlatamab in rural settings.
Tang et al. (Thu,) studied this question.