In a significant development for prostate cancer treatment, CellBion has partnered with MSD (known as Merck & Co. in North America) to investigate a novel combination of radioligand therapy and immunotherapy. The collaboration will evaluate CellBion's PSMA-targeting radioligand, Lutetium (177Lu) DGUL, alongside MSD's established anti-PD-1 therapy, Keytruda (pembrolizumab), in patients with advanced prostate cancer.
First-of-its-Kind Trial in Korea
The groundbreaking study represents the first evaluation of radioligand therapy combined with an immune checkpoint inhibitor in Korea. CellBion CEO Kim Kweon emphasized the historical significance of this collaboration, noting its potential to expand treatment options for patients with limited alternatives.
The partnership emerged following promising interim results from CellBion's ongoing Phase 2 trial of Lu-177-DGUL. A company official revealed that MSD initiated discussions after reviewing these encouraging data, leading to the joint clinical trial agreement. "Both companies share the belief that combining radioligand therapy and immune checkpoint inhibitors could provide a novel approach to treating refractory cancer," the official stated.
Trial Design and Objectives
The Phase 1 study will involve approximately 30 patients with Taxane-naïve, treatment-resistant prostate cancer. The trial design includes:
- A monotherapy arm receiving Lu-177-DGUL alone
- A combination arm receiving both Lu-177-DGUL and Keytruda
- Primary endpoint focused on safety assessment
- Secondary endpoints including progression-free survival (PFS) and overall survival (OS)
Parallel Development Programs
CellBion is maintaining momentum on multiple fronts. Their independent Phase 2 trial of Lu-177-DGUL is expected to complete patient enrollment in the first half of 2024, with final results anticipated in the second half of the year. These findings will support a regulatory approval application.
The new combination trial with MSD will proceed on a separate track, beginning with Phase 1 studies for a new indication. CellBion plans to submit an investigational new drug (IND) application to Korea's Ministry of Food and Drug Safety (MFDS) in the first half of 2024, with first patient dosing targeted for the second half of the year.
Future Expansion Plans
Looking beyond the initial Phase 1 trial in Korea, the companies have already outlined plans for expansion. Pending positive results, they intend to accelerate development efforts and broaden their collaboration, including a planned Phase 2 combination study in the United States.
