Royalty Pharma has acquired a royalty interest in Amgen’s immunotherapy Imdelltra, used for extensive-stage small cell lung cancer (ES-SCLC), in a deal worth up to $950 million. Imdelltra, a bispecific T-cell engager activating patients’ immune systems to eliminate cancer cells, received accelerated FDA approval in May 2024 following successful Phase II trials. The therapy addresses a disease affecting 15% of lung cancer patients, with U.S. annual cases exceeding 200,000. Sales surpassed $215 million in the first half of 2025, exceeding expectations and forecasting over $2.8 billion by 2035. Royalty Pharma will pay $885 million upfront to BeOne Medicines, retaining exclusive distribution rights in China.