A recent Allergan clinical trial testing their depression drug Rapastinel and placebo both in combination with antidepressant therapy (ADT)in patients with major depressive disorders who evidenced a partial response to ADT. According to Reuters, this news is welcome for activist and billionaire hedge fund manager David Tepper who seeks the sale of the company. The industry sponsor has struggled with disappointing 2019 revenues.
As described in Wikipedia, Rapastinel (INN) (former developmental code names GLYX-13, BV-102) is a novel antidepressant that is under development by Allergan (previously Naurex) as an adjunctive therapy for the treatment of treatment-resistant major depressive disorder. It is a centrally active, intravenously administered (non-orally active) amidated tetrapeptide (Thr-Pro-Pro-Thr-NH2) that acts as a selective, weak partial agonist (mixed antagonist/agonist) of an allosteric site of the glycine site of the NMDA receptor complex (Emax ≈ 25%). The drug is a rapid-acting and long-lasting antidepressant as well as robust cognitive enhancer by virtue of its ability to both inhibit and enhance NMDA receptor-mediated signal transduction.
Back to the failure. After three acute studies titled RAP-MD-01,-02,-03) the investigational drug treatment arms failed to differentiate from placebo on both the primary and key secondary endpoints on patients with a major depressive disorder. David Nicholson, chief R&D for Allergan stated, “we are deeply disappointed with these results, and they are a vivid reminder that drug development is extremely challenging, especially in mental health.” It comes at a problematic point in time as Allergan was planning to reenergize its CNS therapeutic area. Shares are falling and undoubtedly some heads will roll.