Addex Spin-Out Neurosterix Commences Phase 1 Clinical Study of NTX-253 for Schizophrenia
Geneva, Switzerland, January 7, 2026 - Addex Therapeutics (SIX: ADXN and Nasdaq: ADXN), a clinical-stage biopharmaceutical company specializing in small molecule allosteric modulators for neurological disorders, has announced the initiation of a Phase 1 clinical study of NTX-253 by its spin-out company, Neurosterix.
Overview of the Phase 1 Study
The Phase 1 study aims to evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of NTX-253, a potent, selective, orally available positive allosteric modulator (PAM) of the muscarinic M4 receptor. This receptor is being developed to treat schizophrenia, representing a promising new direction in medication.
Significance of NTX-253 Development
Tim Dyer, CEO of Addex Therapeutics, remarked, “The progression of NTX-253 into clinical studies represents an important milestone for both Neurosterix and Addex. Selective modulation of the M4 receptor through a PAM offers a novel therapeutic approach that could provide patients with schizophrenia a significant improvement in efficacy and safety.”
Background on Neurosterix
Neurosterix was created as a spin-out from Addex in April 2024, raising $65 million in a Series A financing round led by Perceptive Advisors. Addex Therapeutics retains a 20% equity interest in Neurosterix, indicating its ongoing commitment and involvement in this innovative venture.
The Role of M4 PAMs in Treating Schizophrenia
The M4 muscarinic receptor is a validated target for schizophrenia treatment due to its ability to indirectly modulate dopamine signaling. NTX-253 fine-tunes muscarinic signaling, potentially reducing psychotic symptoms while avoiding the adverse movement disorders and metabolic complications typical of traditional dopamine antagonists.
Key advantages of M4 PAMs include:
- Potential for robust antipsychotic-like activity
- A favorable safety profile based on preclinical studies
- A reduced risk of peripheral muscarinic side effects found in direct agonists
About Addex Therapeutics
Addex Therapeutics is a pioneering clinical-stage biopharmaceutical company focused on the development of allosteric modulators for neurological disorders. Its lead candidate, dipraglurant, is under consideration for further development in brain injury recovery, and the company is progressing various candidates across multiple indications.
The company’s shares trade under the stock symbol ADXN on both the SIX Swiss Exchange and NASDAQ Capital Market. For more details, visit www.addextherapeutics.com.
Forward-Looking Statements
This press release contains forward-looking statements that are subject to risks and uncertainties, which may cause actual results to differ materially. Addex disclaims any obligation to update any forward-looking statements.