Amgen reports 58% lower death risk with IMDELLTRA combination in lung-cancer maintenance trial

On October 24, 2026, Amgen announced interim results from its Phase 3 DeLLphi-305 trial: adding IMDELLTRA to AstraZeneca's immunotherapy IMFINZI reduced the relative risk of death during follow-up by 58% compared with IMFINZI alone. Phase 3 is a large, late-stage test of a treatment's effectiveness; the results were presented at the European Society for Medical Oncology congress and simultaneously published in The New England Journal of Medicine.^[1]

The study involved extensive-stage small-cell lung cancer, an aggressive cancer that has spread widely. Patients entered maintenance treatment—continued drug treatment to keep the disease under control—after their cancer had not worsened following initial chemotherapy plus immunotherapy.^[2] Amgen said nearly 80% of patients receiving the combination were alive at one year, compared with 53% receiving IMFINZI alone.^[1]

The results give doctors a stronger efficacy case for adding IMDELLTRA after initial treatment. If regulatory clearance for this use, physician adoption and insurance coverage follow, Amgen could gain additional maintenance-treatment demand. Because IMFINZI remains part of the combination, AstraZeneca could also strengthen its drug's position at this stage of care.^[1][2]

The commercial opportunity still depends on implementation. The supplied coverage gives no regulatory decision, pricing or coverage terms for this use, so it does not support a sales estimate. For competing drug developers, the survival benefit raises the benchmark their treatments must meet to win doctors' and payers' support.^[1][2]

Impact