Tarlatamab Earns Traditional FDA Approval in ES-SCLC

The FDA has granted traditional approval to tarlatamab-dlle (Imdelltra) for adult patients with extensive-stage small cell lung cancer (ES-SCLC) following disease progression on or after prior platinum-containing chemotherapy, according to a press release from the agency.¹

Supporting data for the approval came from the phase 3 DeLLphi-304 trial (NCT05740566), in which 509 patients with previously treated SCLC received tarlatamab or investigator's choice of chemotherapy with topotecan, lurbinectedin, or amrubicin. Topline data revealed a median overall survival (OS) of 13.6 months (95% CI, 11.1-not evaluable [NE]) with tarlatamab vs 8.3 months (95% CI, 7.0-10.2) with standard of care (HR, 0.60; 95% CI, 0.47-0.77; P <.001). Additionally, the median progression-free survival (PFS) was 4.2 months (95% CI, 3.0-4.4) vs 3.2 months (95% CI, 2.9-4.2) in each respective arm (HR, 0.72; 95% CI, 0.59-0.88; P <.001).

Investigators also noted that tarlatamab significantly improved dyspnea at week 18 vs standard therapy.

Prescribing information for tarlatamab includes warning for life-threatening or fatal cytokine release syndrome and neurologic toxicity such as immune effector cell-associated neurotoxicity syndrome. Other toxicities may include infections, cytopenias, hepatotoxicity, hypersensitivity, and embryo-fetal toxicity.

The agency approved the agent at a recommended dose of 1 mg on day 1 of cycle 1 followed by 10 mg on days 8 and 15 and then every 2 weeks until progressive disease or unacceptable toxicity.

The FDA previously granted accelerated approval to tarlatamab for this SCLC population in May 2024.² Supporting data for the accelerated approval came from the phase 2 DELLphi-301 trial (NCT05060016).

References

1. FDA grants traditional approval to tarlatamab-dlle for extensive stage small cell lung cancer. News release. FDA. November 19, 2025. Accessed November 19, 2025. https://tinyurl.com/yc7b96fw
2. FDA grants accelerated approval to tarlatamab-dlle for extensive stage small cell lung cancer. News release. FDA. May 16, 2024. Accessed November 19, 2025. https://tinyurl.com/48k34rw5