Phase 3 DeLLphi-304 Trial: Tarlatamab Shows Significant OS Improvement in SCLC

The phase 3 DeLLphi-304 trial has met its primary end point, demonstrating a “statistically significant and clinically meaningful improvement” in overall survival (OS) with tarlatamab-dlle (Imdelltra, Amgen) compared with local standard-of-care chemotherapy, according to an announcement from Amgen.

The global trial is evaluating the safety and efficacy of the first-in-class immunotherapy in patients with patients with small cell lung cancer (SCLC) that progressed during or after a single line of platinum-based chemotherapy. Investigators randomized patients to receive tarlatamab or local standard-of-care chemotherapy. The chemotherapy was topotecan in all countries except Japan; lurbinectedin in the US, Canada, Australia, Singapore, Korea; and amrubicin in Japan. The primary outcome measure of the trial is OS.

Jay Bradner, MD, executive vice president of research and development at Amgen, weighed in on the results of the preplanned interim analysis in a statement.

“Small cell lung cancer is one of the most aggressive malignancies, with a high unmet need for more effective therapies. The topline results from DeLLphi-304 demonstrate overwhelming clinical benefit for people living with this devastating disease and affirm IMDELLTRA as standard of care,” Dr. Bradner said. “We look forward to sharing these results with the scientific community and health authorities as we continue our efforts to bring IMDELLTRA to patients worldwide.”

Officials explained that the safety profile of tarlatamab “was consistent with its known profile” and that “detailed data from DeLLphi-304 will be presented at an upcoming medical congress.”

Tarlatamab-dlle is currently indicated for the treatment of adults with extensive-stage SCLC who have disease progression during or after platinum-based chemotherapy.

“This indication is approved under accelerated approval based on overall response rate and duration of response,” officials said in the announcement. “Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial(s).”

Source:

Imdelltra® demonstrated superior overall survival in small cell lung cancer. News release. Amgen. April 11, 2025. Accessed April 13, 2025. https://wwwext.amgen.com/newsroom/press-releases/2025/04/imdelltra-demonstrated-superior-overall-survival-in-small-cell-lung-cancer?linkId=100000357149894