Allergan plc exercised its option to acquire AGN-241751, an oral small-molecule N-methyl-D-aspartate (NMDA) receptor modulator that was discovered by Aptinyx Inc. and advanced under an ongoing research collaboration between the companies. Allergan gained option rights to certain small molecules from the Aptinyx discovery platform under a research collaboration initiated in conjunction with its 2015 acquisition of Naurex Inc., which simultaneously spun out Aptinyx and its platform. As part of that transaction, Allergan also acquired rapastinel, an intravenously administered NMDA receptor modulating tetrapeptide that subsequently received breakthrough therapy designation from the FDA and has advanced to phase III development in major depressive disorder (MDD). (See BioWorld Today, Sept. 16, 2015.)