Addex Therapeutics (SIX: ADXN and Nasdaq: ADXN), a clinical-stage biopharmaceutical company focused on developing a portfolio of novel small molecule allosteric modulators for neurological disorders, announced that its spin-out company, Neurosterix, in which Addex holds a 20% equity interest, has completed its Phase 1 clinical studies evaluating NTX-253 and plans to advance NTX-253 into Phase 2 clinical development. NTX-253 is a positive allosteric modulator (PAM) of the muscarinic M4 receptor being developed for the treatment of schizophrenia.

“Completing Phase 1 and the decision by Neurosterix to progress NTX-253 into Phase 2 studies in schizophrenia patients is a significant achievement,” said Tim Dyer, CEO of Addex. “The well-designed study combining healthy volunteers and schizophrenia patients within a single study has provided important safety and pharmacokinetic data.”

The clinical study includes a multi-part, ascending-dose design intended to efficiently characterize NTX-253’s clinical profile and support subsequent patient-focused development. The study includes both single ascending dose (SAD) and multiple ascending dose (MAD) components, incorporating key translational elements such as food-effect and cerebrospinal fluid (CSF) assessments. The studies included both healthy volunteers and stable schizophrenia patients, and has provided important safety and pharmacokinetic data.

Neurosterix was spun-out of Addex in April 2024, raising $65 million in a Series A financing led by funds affiliated with Perceptive Advisors. Addex retains a 20% equity interest in Neurosterix.