Royalty Pharma has acquired BeOne Medicines' royalty rights to IMDELLTRA (tarlatamab-dlle) for up to $950 million, marking a significant transaction in the oncology space for the first-in-class bispecific T-cell engager approved for small cell lung cancer treatment.
Transaction Details
Under the agreement, Royalty Pharma will pay BeOne Medicines $885 million upfront for approximately 7% royalty rights on worldwide net sales of IMDELLTRA, excluding China. BeOne retains an option to sell additional royalty portions for up to $65 million within the next 12 months. The companies will share royalties on annual net sales exceeding $1.5 billion, with royalty duration expected to extend through 2038-2041.
"We are excited to acquire this royalty stream from BeOne Medicines, a global oncology company advancing innovative treatments," said Pablo Legorreta, Royalty Pharma's founder and Chief Executive Officer. "IMDELLTRA is reshaping the treatment paradigm for patients with small cell lung cancer, a highly aggressive disease with few treatment options."
IMDELLTRA's Clinical Profile
IMDELLTRA represents a breakthrough immunotherapy that binds to both DLL3 on tumor cells and CD3 on T cells, activating T cells to kill DLL3-expressing cells. This mechanism results in cytolytic synapse formation with cancer cell lysis. DLL3 protein is expressed on SCLC cells in the vast majority of patients but minimally expressed on healthy cells, making it an attractive therapeutic target.
The drug received accelerated approval from the U.S. Food and Drug Administration in May 2024 for treating extensive-stage small cell lung cancer (ES-SCLC) in patients who have progressed on or after receiving platinum-based chemotherapy.
Market Impact and Disease Burden
Small cell lung cancer affects approximately 360,000 patients worldwide annually and carries a poor prognosis with overall survival of approximately 12 months following initial therapy and a five-year survival rate of 7% for patients with invasive disease. IMDELLTRA sales reached $215 million in the first half of 2025 and are projected to exceed $2.8 billion by 2035 based on analyst consensus.
Ongoing Development Program
Amgen is currently conducting multiple Phase 3 studies for IMDELLTRA in front-line small cell lung cancer settings. The development program includes DeLLphi-303, a Phase 1b study evaluating tarlatamab in combination with standard of care therapies in first-line ES-SCLC, and DeLLphi-304, a randomized Phase 3 trial comparing tarlatamab monotherapy with standard of care chemotherapy in second-line treatment.
Additional studies include DeLLphi-306, a randomized placebo-controlled Phase 3 trial following concurrent chemoradiotherapy in limited-stage SCLC, DeLLphi-308 evaluating subcutaneous administration, and DeLLphi-309 examining alternative intravenous dosing regimens.
Strategic Implications
"By monetizing a significant portion of our royalty interest in IMDELLTRA, we are able to strengthen our balance sheet and unlock substantial value," said John V. Oyler, Co-Founder, Chairman and CEO of BeOne. The transaction provides BeOne with increased operational and strategic flexibility while maintaining participation in IMDELLTRA's long-term potential.
BeOne will retain China commercial rights to IMDELLTRA and maintain royalty and other rights to additional assets under its collaboration with Amgen, including xaluritamig, a first-in-class STEAP1 x CD3 XmAb currently being studied in patients with metastatic castration-resistant prostate cancer.
