
The US Food and Drug Administration (FDA) has granted orphan drug designation (ODD) to Plus Therapeutics’ injectable radiotherapy, Rhenium (186Re) Obisbemeda, for treating leptomeningeal metastases (LM) in lung cancer sufferers.
The designation is awarded to drugs aimed at rare conditions (affecting fewer than 200,000 individuals in the US) and comes with benefits such as seven years of market exclusivity.
The ODD for the therapy follows the completion of the single-dose Phase I ReSPECT-LM trial, which determined the recommended Phase II dose.
Plus Therapeutics chief development officer Mike Rosol stated: “Receiving ODD for Rhenium (186Re) Obisbemeda marks a significant milestone in our efforts to develop a much-needed therapy for lung cancer patients with leptomeningeal metastases.
“This designation, in combination with our previously granted fast track designation, strengthens our pathway toward delivering an innovative, targeted radiotherapeutic solution for this highly underserved patient population.”
Plus Therapeutics is currently progressing a Phase II single-dose expansion trial and a Phase I multiple-dose trial.
The company is in discussions with the US regulator to establish the optimal pivotal trial strategy.
A rare cancer complication, LM involves the spread of primary cancer to the cerebrospinal fluid and the leptomeninges around the spinal cord and brain.
Designed to deliver targeted high-dose radiation to central nervous system (CNS) tumours, the therapy improves patient outcomes by offering a more potent radiation dose compared to existing therapies.
The therapy is currently under assessment for recurrent glioblastoma and LM in the ReSPECT-GBM and ReSPECT-LM trials.
Plus Therapeutics widened its collaboration with Piramal Pharma Solutions (PPS) in May 2023 to produce additional current good manufacturing practice liposome intermediate drug products.