Amgen Inc (AMGN): Meaningful Imdelltra Oppty In 1L Maintenance SCLC

At ESMO, Amgen presented Phase 3 DeLLphi-305 data for Imdelltra in first-line maintenance ES-SCLC, showing a meaningful OS benefit (HR 0.42), with median OS of 21.1 months for Imdelltra plus Imfinzi versus 12.7 months for Imfinzi alone, and median PFS improving to 7.4 months from 1.9 months. Amgen plans to file the data with the FDA shortly. J.P. Morgan sees Imdelltra as a potential $5bn+ product as it moves into earlier lines, citing a larger target population (~23k US 1L patients vs ~14k in 2L), significantly longer treatment duration (~2.5x the 2L duration), reduced monitoring requirements and lower adverse-event rates. The broker maintains a Neutral rating.