FDA Grants Orphan Drug Designation to Mocravimod to Improve Outcomes Following Stem Cell Transplantation
KRP203 (mocravimod) is intended to improve outcomes after hematopoietic stem cell transplantation for the treatment of hematologic malignancies.
Priothera Ltd. has announced that the FDA awarded Orphan Drug Designation to KRP203 (mocravimod) to improve outcomes after hematopoietic stem cell transplantation for the treatment of hematologic malignancies. The sphingosine-1-phosphate (S1P) receptor modulator is designed to improve leukemia-free survival by increasing graft-versus-leukemia (GvL) response.
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“We are very pleased that the US FDA granted mocravimod this Orphan Drug designation. This designation emphasizes the importance of developing novel therapeutic options to improve the outcome and success of maintenance therapy following allo-HSCT in blood cancer patients. This is an important milestone as this ODD complements the first ODD granted for prevention of graft-versus-host disease,” said Priothera co-founder and CEO Florent Gros, in a press release. “The two ODDs highlight mocravimod’s dual mode of action which for the first time is being leveraged to improve the allo-HSCT treatment outcomes in hematological malignancies to potentially increase the leukemia free survival—graft-versus-leukemia response—while reducing tissue damage resulting from the graft-versus-host disease.”
Mocravimod is currently being evaluated in the Phase 3 MO-TRANS (NCT05429632) trial, a pivotal global study of the efficacy and safety of the drug as an adjunctive and maintenance treatment to allo-HSCT in 250 adults with acute myeloid leukemia.
The intended dual mode of action for mocravimod seeks to maintain beneficial GvL activity while also decreasing damage to tissue associated with GvHD, which are consequences of allo-HSCT. This represents a high unmet need among patients, with mocravimod potentially improving their quality of life.
Prior testing in a Phase 1b/2a study of multiple autoimmune indications suggest mocravimod may improve the curative potential of allo-HSCT based on a clinically meaningful outcome in patients with hematologic malignancies undergoing allo-HSCT. Mocravimod was previously granted an ODD to prevent graft-versus-host disease.
Reference
BioSpace. Priothera – US FDA grants Orphan Drug Designation to mocravimod to improve the outcome of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with hematologic malignancies. News release. November 27, 2023. Accessed November 28, 2023. https://www.biospace.com/article/releases/priothera-us-fda-grants-orphan-drug-designation-to-mocravimod-to-improve-the-outcome-of-allogeneic-hematopoietic-stem-cell-transplantation-allo-hsct-in-patients-with-hematologic-malignancies
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