Allergan has decided to acquire biopharmaceutical firm Aptinyx ’s drug candidate AGN-241751 and advance it as a treatment for major depressive disorder (MDD) patients.

AGN-241751 is an oral small-molecule modulator of N-methyl-D-aspartate (NMDA) receptor discovered by Aptinyx using its chemistry platform.

Allergan gained option rights to certain small molecules from the Aptinyx discovery platform under a research alliance formed in 2015 when it acquired Aptinyx’s predecessor company Naurex .

The acquisition also provided Allergan with an intravenous NMDA receptor modulating tetrapeptide called rapastinel, which has subsequently secured the US Food and Drug Administration’s (FDA) breakthrough therapy status and is being studied by the company in Phase III clinical trials for MDD.

The research collaboration between Allergan and Aptinyx aims to discover and characterise new small-molecule NMDA receptor modulators using the latter’s chemistry platform.

“Through our productive research collaboration with Aptinyx, we have gained important insights into NMDA receptor modulation as a potential therapeutic approach for depression.”

Under the terms of the collaboration, Allergan funds certain costs and gains the ability to buy a pre-specified number of candidates for development and commercialisation in select indications only.

Allergan chief research and development officer C David Nicholson said: “Through our productive research collaboration with Aptinyx and parallel development of rapastinel, we have gained important insights into NMDA receptor modulation as a potential therapeutic approach for depression.

“We plan to advance AGN-241751 for the treatment of MDD and believe its pharmacological profile will enable it to become an oral complement to rapastinel, further bolstering our pipeline of therapeutics addressing areas of significant unmet medical need.”