OSE Immunotherapeutics: FDA Grants Orphan Drug Designation to Anti-Rejection Treatment
OSE Immunotherapeutics announces that its partner Veloxis Pharmaceuticals has received orphan drug designation from the FDA for pegrizeprument (VEL-101) in the prevention of cardiac graft rejection. This recognition comes a few months after a similar designation was granted for liver transplantations.
Second Orphan Designation in Less than Four Months
Pegrizeprument, a monovalent monoclonal antibody fragment discovered and developed by OSE Immunotherapeutics, has received FDA orphan drug designation for the prophylaxis of cardiac allograft rejection. This designation follows the one granted in January 2026 for the prevention of organ rejection in patients undergoing liver transplantation. The drug has been licensed to Veloxis Pharmaceuticals since April 2021, which is responsible for global development, manufacturing, and future commercialization of the product for all transplantation-related indications.
Specific Immunomodulatory Mechanism of Action
Pegrizeprument is a pegylated antibody fragment that binds to CD28 and blocks the co-stimulation of effector T cells by CD28, without blocking CTLA-4. This approach is intended to produce a dual mechanism of action: direct blocking of CD28-mediated T cell activation, combined with preserved immunosuppressive functions mediated by CTLA-4. The product is currently in development to prevent rejection following solid organ transplantation.
