Plus Therapeutics Receives FDA Orphan Drug Designation for REYOBIQ™ in Pediatric Malignant Gliomas

On April 8, 2026, Plus Therapeutics announced that the U.S. Food and Drug Administration (FDA) has granted Orphan Drug Designation (ODD) to its lead radiotherapeutic candidate, REYOBIQ™ (rhenium Re186 obisbemeda), for the treatment of pediatric malignant gliomas. Notably, the FDA expanded the scope of the designation beyond the company's original request to include pediatric ependymoma. REYOBIQ is an injectable radiotherapy designed to deliver targeted high-dose radiation directly to central nervous system (CNS) tumors while minimizing exposure to healthy tissue. The Orphan Drug Designation provides Plus Therapeutics with several incentives, including seven years of market exclusivity upon potential regulatory approval, tax credits for clinical trial expenses, and exemptions from certain FDA fees. This milestone follows the FDA's recent clearance of the company's Investigational New Drug (IND) application to evaluate REYOBIQ in pediatric patients. The therapy is currently being studied across multiple CNS indications, including recurrent glioblastoma and leptomeningeal metastases, through the ReSPECT clinical trial programs.