Allergan has reported negative top-line results from three pivotal Phase III clinical trials of its depression drug rapastinel.
The company said that the drug failed to meet the primary and key secondary endpoints in all of the studies.
Rapastinel is being developed as a NMDA receptor modulator. Preclinical testing showed direct enhancement in NMDAR activity via a new site independent of the glycine co-agonist site.
The Phase III RAP-MD-01,-02,-03 trials compared the safety, efficacy, and tolerability of rapastinel to placebo, both in combination with antidepressant therapy (ADT), in patients with major depressive disorder (MDD).
Data showed that the rapastinel treatment group did not differentiate from placebo on the primary and key secondary endpoints.
However, the drug was well tolerated and exhibited a safety and tolerability profile similar to placebo.
The company also performed interim analysis of the rapastinel relapse prevention study (RAP-MD-04), which indicated that the primary and key secondary endpoints will not be met.
Rapastinel's efficacy, safe, y and tolerability are also being studied in a Phase II proof of concept suicidality compared to placebo in addition to standard of care (SOC) of patients with MDD at imminent risk of suicide.
Allergan chief research and development officer David Nicholson said: “We are deeply disappointed with these results, and they are a vivid reminder that drug development is extremely challenging, especially in mental health.
“We will evaluate the impact of these data on the ongoing monotherapy MDD program and suicidality in MDD study. We expect to make a decision on these programmes during the course of 2019.”
This announcement comes a day after the US Food and Drug Administration (FDA) approved Janssen’s Spravato (esketamine) nasal spray as an adjuvant treatment in MDD patients.