Allergan plc announced new pharmacology research for its investigational compound rapastinel, which is currently being studied in Phase 3 trials for the treatment of major depressive disorder (MDD). Published in the International Journal of Neuropsychopharmacology, the preclinical research supports that rapastinel exhibited rapid and sustained antidepressant effects through positive modulation of the NMDA (N-methyl-D-aspartate) receptor and suggests that it may work differently from NMDA receptor antagonists like ketamine and S-ketamine (esketamine).