Neumora Therapeutics’ Schizophrenia Drug NMRA-266 Faces FDA Hold Over Convulsions in Rabbits

- Neumora Therapeutics' Phase 1 trial of NMRA-266, a schizophrenia drug, has been placed on hold by the FDA due to convulsions observed in preclinical rabbit studies.
- None of the 30 healthy adult humans dosed with NMRA-266 in the trial have experienced convulsions.
- Neumora is working with the FDA to resolve the clinical hold and will provide updates.
- The company is also developing other M4 muscarinic receptor-targeting molecules, including NMRA-511, which has faced a partial clinical hold for dose-limiting toxicities.
- NMRA-266 is a positive allosteric modulator (PAM) of the M4 muscarinic receptor.
- Neumora is advancing preclinical safety and toxicology work with backup compounds and expects to submit an Investigational New Drug (IND) application in 2025.
- The company's stock dropped 13% to $11.84 in premarket trading on Monday, April 15, 2024, following the announcement.
- Neumora's lead asset, navacaprant, is in a late-stage trial for major depressive disorder, and the company is also developing NMRA-511, a vasopressin 1a receptor antagonist.
- The FDA clinical hold may set NMRA-266 further behind competitors like KarXT by Bristol Myers Squibb and Neurocrine's M4 agonist NBI-1117568.
- William Blair analysts noted the focus of Neumora investors remains on navacaprant, a kappa opioid receptor antagonist.