Tarlatamab (AMG 757) and durvalumab with durvalumab alone in first-line - (DeLLphi-305)

Sept. 8, 2026: Amgen (NASDAQ: AMGN) reported that the Phase 3 DeLLphi-305 trial met its primary endpoint at a prespecified interim analysis, with IMDELLTRA (tarlatamab-dlle) plus AstraZeneca’s Imfinzi (durvalumab) showing a statistically significant and clinically meaningful overall survival benefit versus durvalumab alone in first-line maintenance extensive-stage small cell lung cancer (ES-SCLC). The study also met secondary endpoints for progression-free survival and objective response rate.

DeLLphi-305 enrolled 563 patients with ES-SCLC whose disease had not progressed after durvalumab, platinum chemotherapy, and etoposide; patients were randomized 1:1 to IMDELLTRA plus durvalumab or durvalumab alone. The trial included patients with treated and untreated asymptomatic brain metastases. Safety for the combination was consistent with known profiles of the individual drugs, with no new or unexpected safety signals.

Amgen said it plans to present detailed DeLLphi-305 data at an upcoming international medical congress and share the results with regulatory authorities.

The release also lists ongoing tarlatamab studies: DeLLphi-304 and -315 in second-line ES-SCLC, DeLLphi-306 in limited-stage SCLC, DeLLphi-308/-309 on alternative formulations/dosing, and DeLLphi-310/-311/-312/-313 in combination regimens.