GSK plc (GSK), a commercial-stage biopharmaceutical company, announced that it has received Orphan Drug Designation (ODD) for Ojjaara from the U.S. Food and Drug Administration (FDA) and European Medicines Agency (EMA) for the treatment of Vacuoles, E1 enzyme, X-linked, Autoinflammatory, Somatic (VEXAS) syndrome.
VEXAS syndrome is an auto-inflammatory condition caused by somatic mutations in the UBA1 gene located on chromosome X. It is classified as a clonal myeloid disorder with rheumatologic and hematologic clinical features. It disproportionately affects men with poor prognosis and a five-year mortality rate of 30-40%; there are currently no approved treatments for VEXAS syndrome.
Ojjaara, also known as "Momelotinib," has an inhibitory potential along three key signaling pathways: Janus kinase (JAK)1, JAK2, and activin A receptor type 1 (ACVR1). The candidate's inhibition of JAK1 and JAK2 improves constitutional symptoms and splenomegaly. Additionally, the drugs' inhibition of ACVR1 leads to a decrease in circulating hepcidin levels, improving iron availability for erythropoiesis and thereby alleviating anemia.
The designation was supported by case studies that demonstrated JAK inhibitors as an effective therapeutic option for VEXAS syndrome. Additionally, evidence from a case report indicated clinical benefit of momelotinib in treating patients with VEXAS.
The report showed improvements in VEXAS-related inflammation, hematological manifestations, and symptoms. The company further added the designation provides support for development efforts and regulatory evaluations for new medicines with the potential to treat or prevent rare disorders.
The Phase 2/3 ATLAS trial for VEXAS is underway, advancing momelotinib's broader development program, noted the firm.
Momelotinib is currently approved, under the brand name Ojjaara, for treatment in the U.S. for intermediate- or high-risk myelofibrosis in adults with anemia. It is also approved in the EU and UK for the treatment of myelofibrosis with disease-related splenomegaly or symptoms in adults with moderate-to-severe anemia.
GSK shares closed Thursday at $52.86, up 3.30%. In the overnight market the shares are trading at $53.26, up 0.79%.
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