Sosei Heptares’ partner Neurocrine Biosciences Initiates Phase 1 Clinical Study Evaluating Effects of NBI-1117570 in Healthy Adults

• NBI-1117570 is an investigational, oral, muscarinic M1/M4 selective dual agonist discovered by Sosei Heptares that may have the potential to treat neurological and neuropsychiatric conditions
• NBI-1117570 is the second compound to advance into clinical development from a portfolio of selective muscarinic receptor agonists licensed by Sosei Heptares to Neurocrine following NBI-1117568, an oral, selective muscarinic M4 receptor agonist, which is in Phase 2 clinical trials as an investigational treatment for schizophrenia

Tokyo, Japan and Cambridge, UK, 12 September 2023 – Sosei Group Corporation (“the Company”; TSE: 4565), has been notified by its partner Neurocrine Biosciences Inc. (“Neurocrine”; Nasdaq: NBIX), a leading neuroscience-focused biopharmaceutical company, that it has initiated its Phase 1 first-in-human clinical study to evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of investigational compound NBI-1117570 in healthy adult participants. NBI-1117570 is an investigational, oral, muscarinic M1/M4 selective dual agonist that may have the potential to treat neurological and neuropsychiatric conditions and was developed utilising Sosei Heptares' structure-based drug design platform.

“Initiation of this Phase 1 study represents an important step forward for NBI-1117570, a potentially first-in-class, orally active, selective investigational dual M1/M4 agonist,” said Eiry W. Roberts, M.D., Chief Medical Officer at Neurocrine Biosciences. "The selectivity profile of NBI-1117570 in targeting M1 and M4 receptors may provide an opportunity to treat symptoms of both psychosis and cognition across a broad range of neurological and neuropsychiatric conditions.”

Matt Barnes, President of Heptares Therapeutics and Head of UK R&D, said: “We are delighted that Neurocrine is progressing this unique M1/M4 selective agonist into clinical development to target important unmet medical needs in neurological and neuropsychiatric disorders. NBI-1117570 is the second candidate to advance into clinical trials from the portfolio of selective muscarinic receptor agonists discovered and licensed by Sosei Heptares to Neurocrine in 2021.  We look forward to reporting further progress from these and potentially other candidates under this highly productive partnership.”

The clinical development milestone achieved with NBI-1117570 as announced does not trigger a milestone payment from Neurocrine to Sosei Heptares under the terms of the 2021 agreement between the companies. Milestone payments, under the agreement, are payable upon the achievement of multiple, defined development events for each program. Sosei Heptares will announce the receipt of any milestone payments in accordance with TSE reporting requirements.