Syremis Therapeutics made its debut Thursday with $165 million in series A financing in hand, hoping to carve out a foothold in a space reshaped by the FDA approval last year of Bristol Myers Squibb's dual M1/M4 muscarinic agonist Cobenfy (xanomeline / trospium chloride) for schizophrenia.Co-led by Dexcel Pharma and Third Rock Ventures, the round also drew participation from the likes of Bain Capital Life Sciences, GV, QVT and Pictet.The startup's lead asset, ST-905 – which, like Cobenfy, also targets the M1 and M4 muscarinic receptors – is working its way through Phase I, targeting schizophrenia as well as other neuropsychiatric disorders."Schizophrenia and Alzheimer's disease psychosis remain two of the most challenging of all neuropsychiatric disorders," said Steve Paul, Syremis co-founder and former CEO of Karuna Therapeutics, the company BMS shelled out $14 billion for in 2023 to get its hands on Cobenfy, then still in development and known as KarXT.'Balanced' M1/M4 profilePaul, who now sits on the Syremis board, suggested ST-905's "balanced M1/M4 profile and promising pharmaceutical properties" could allow the company to build on the clinical progress made by Cobenfy (see – JPM25: BMS looks to position Cobenfy as a 'pipeline within a product'). Though it hasn't all been smooth sailing for BMS's drug; earlier this year it failed to showed enough benefit in a Phase III trial as an add-on therapy for schizophrenia, and more recently, a review tuned up clinical site "irregularities" in another study, this time for or psychosis associated with Alzheimer's disease.The muscarinic target has also seen disappointing results elsewhere, with AbbVie's emraclidine – a selective M4 muscarinic modulator – failing to live up to expectations in a pair of mid-stage schizophrenia studies late last year.Syremis argues that ST-905's "differentiated" potency and properties could make it a best-in-class therapy across multiple neuropsychiatric indications and symptom domains, while also supporting once-daily oral dosing and the potential for a long-acting injectable version.Meanwhile, the startup's second programme, ST-901, takes a different tack. That asset is an NMDA receptor antagonist currently in IND-enabling studies, with plans to enter Phase I next year for major depressive disorder and bipolar depression.Both ST-905 and ST-901 originated at Clexio Biosciences before being spun out into Syremis, which is led by CEO Elisabeth Kogan.