Background Vafidemstat (ORY-2001) is a clinical stage inhibitor of the Lysine Specific Demethylase KDM1A in development for treatment of neurodegenerative and psychiatric diseases. KDM1A demethylates H3K4me1/2 and together with the histone deacetylases HDAC1/2, it forms part of co-repressor complexes recruited by zinc finger factors to control transcription. The exact role of KDM1A in neuroinflammation remained to be explored.
Methods Compounds were administered p.o. gavage to mice with MOG35-55 induced experimental autoimmune encephalomyelitis or mice infected with Theiler’s murine encephalomyelitis virus. Immune cell infiltration was analyzed by immunohistochemistry. Cytokine and chemokine levels were analyzed by ELISA. Genome wide gene expression in spinal cord and brain were analyzed by two-color microarray analysis and qRT-PCR.
Results ORY-2001 improved the clinical score in mouse experimental autoimmune encephalomyelitis and in mice infected with the Theiler’s murine encephalomyelitis virus. The compound reduced lymphocyte egress and infiltration of immune cells in the spinal cord and prevented demyelination. ORY-2001 was more effective and/or faster acting than a sphingosine 1-phosphate receptor antagonist in the effector phase of the disease and reduced the induction of the inflammatory gene expression signature in the central nervous system more potently. Gene expression changes and axonal protection in animals, and protection against glutamate excitoxicity in spinal cord explants support that ORY-2001 has neuroprotective qualities.
Conclusions ORY-2001 exerts therapeutic activity in two mouse models of multiple sclerosis. The anti-inflammatory properties of ORY-2001 are being tested in a Phase IIa clinical trial in patients with relapse remitting and secondary progressive multiple sclerosis, and in severely ill COVID-19 patients at risk for acute respiratory distress syndrome.