CAS Number 1421866-48-9 ChemSpider 52085607 | PubChem CID 71249967 UNII TTT1F11FZB | |
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Legal status US: Investigational New Drug Synonyms NRX-1074, AGN-241660, Threonyl-prolyl-2R-(2-benzyl)-prolyl-threonine amide | ||
Apimostinel is a novel antidepressant, acting as a selective partial agonist of an allosteric site of the glycine site of the NMDA receptor complex, which is under investigation by Naurex (recently acquired by Allergan for $560 million in late 2015) for the treatment of major depressive disorder. As of 2015, an intravenous formulation of apimostinel is in a phase II clinical trial for MDD, and an oral formulation is concurrently in phase I trials for MDD.
Its mechanism of action and effects are similar to those of rapastinel (GLYX-13), which is under development as an adjunctive therapy for treatment-resistant depression also by Naurex. However, apimostinel is 100-fold more potent by weight and, whereas rapastinel must be administered via intravenous injection, is orally-active. Apimostinel is intended by Naurex as an improved, follow-up drug to rapastinel. Similarly to rapastinel, apimostinel is an amidated tetrapeptide, and has almost an identical chemical structure to rapastinel, but has been structurally modified via the addition of a benzyl group. The drug has shown rapid antidepressant effects in pre-clinical models of depression. In addition, similarly to rapastinel, it is well-tolerated and lacks the schizophrenia-like psychotomimetic effects of other NMDA receptor antagonists such as ketamine.
Commercial competitors of apimostinel include AV-101 from VistaGen Therapeutics and Cerecor's CERC-301.[8]
Naurex
Naruex, the original company responsible for apimostinel, was a pharmaceutical company that developed drug candidates as NMDA receptor modulators. The company was acquired by Allergan in later 2015, who continued the clinical trials for Naurex's NMDA receptor modulator drugs. Allergan went public in 1993 as Watson Pharmaceuticals, Inc and was rebranded as Allergan in 2015 after the acquisition of several pharmaceutical companies. Allergan trades on the New York Stock Exchange under the ticker AGN.
In mid-2016, the acquired Naurenx, now rebranded as Aptinyx, announced a $65 million start up round with venture capital companies including New Leaf Venture Partenrs aimed towards NMDA modulation for the treatment of Parkinson's disease and PTSD.