Neurosterix has raised $105 million in series B financing, with the company and parent Addex Therapeutics positioning the cash primarily behind a planned phase 2 trial of NTX-253 in schizophrenia.
The Switzerland-based company was launched by Addex in April 2024 with a $65 million series A led by funds affiliated with Perceptive Advisors. Addex said the latest round came from a “syndicate of leading life science investors,” but it did not identify the backers. Addex did not participate in the financing and now holds an 8.5% equity interest in Neurosterix, down from the 20% stake it retained when the spinout was created.
For investors, the signal is less the headline size than the target use of proceeds: Neurosterix is concentrating fresh capital on a single mid-stage schizophrenia program while still keeping room for earlier neuropsychiatric assets. In a CNS market where development risk has repeatedly cut off funding, that kind of earmarked raise suggests continued appetite for mechanism-specific bets rather than broad platform stories.
The Pipeline Focus
The top spending priority is NTX-253, which Neurosterix describes as a highly selective muscarinic M4 positive allosteric modulator, or PAM. The oral drug is designed to fine-tune muscarinic signaling in the brain to reduce psychosis symptoms.
Neurosterix has already completed phase 1 single- and multiple-ascending-dose clinical studies of NTX-253. The company’s investment case appears to rest on the idea that a selective M4 approach could separate antipsychotic benefit from some of the tolerability burdens associated with older dopamine antagonists. Addex said the hope is to avoid the movement disorders and metabolic complications that can be associated with approved traditional dopamine antagonists for schizophrenia.
A portion of the financing will also support the broader pipeline, including NTX-819, an mGlu7 negative allosteric modulator for mood and anxiety disorders, and NTX-529, another M4 PAM aimed at additional psychosis- and mood-related disorders.
The Corporate Structure
Neurosterix is helmed by CEO Fred Callori, who is also a managing director at Perceptive. That link matters because the company was built from the start as a vehicle to move Addex’s allosteric neuropsychiatry assets into a separately financed structure.
That strategy has a practical backdrop. When Addex launched Neurosterix in 2024, part of the stated goal was to reduce the parent company’s operating costs and extend its cash runway into this year. The new round advances that model again: outside capital is carrying the next phase of development while Addex remains an equity holder rather than the direct funder.
The financing also arrives after uneven partnership history for Addex’s PAM work. In 2024, Johnson & Johnson discontinued development of an Addex-partnered mGlu2 receptor PAM after poor phase 2 epilepsy data, and two months ago Indivior Pharmaceuticals ended its PAM collaboration with Addex ahead of Indivior’s merger with Supernus. Against that record, a $105 million private round is a more useful validation of investor willingness to keep backing the allosteric thesis than management rhetoric alone.
