Amgen’s Imdelltra lands major new lung cancer victory

Amgen’s lung cancer drug Imdelltra notched a major new win in a late-stage trial:
the Phase 3 DeLLphi-305 study showed a statistically significant overall survival benefit when Imdelltra was combined with AstraZeneca’s Imfinzi versus Imfinzi alone in first-line maintenance treatment for extensive-stage small cell lung cancer.

The Sept. 8, 2026 results also showed improvements in progression-free survival and objective response rate, with no new or unexpected safety signals reported.

This matters because it could move Imdelltra earlier in the treatment journey for small cell lung cancer, an aggressive and hard-to-treat disease.

Imdelltra had already secured U.S. traditional FDA approval in November 2025 for ES-SCLC after progression on platinum-based chemotherapy, following earlier accelerated approval in 2024.

The new result builds on prior evidence that Imdelltra reduced the risk of death by 40% and extended median overall survival to 13.6 months versus 8.3 months in a previous Phase 3 setting.