Allergan highlights preclinical evidence of cognitive safety for fast-acting depression drug

Ketamine has long been a topic of considerable fascination in academic and industry research circles. The powerful anesthetic has a well known ability to trigger a rapid, though short-lived, response for patients suffering from severe depression and suicidal thinking. It also is known for an alarming safety profile, spurring problems with cognition as well as dissociative behavior and hallucinations.

So when Allergan ($AGN) bought out Naurex, it continued to study whether its next-gen take on ketamine--an NMDA drug called GLYX-13, or rapastinel--had the same problems. And comparing the impact of rapastinel compared to ketamine in mice, investigators for the company say that their drug was able to work rapidly without the same impact on cognitive function.

"This work demonstrates that rapastinel, unlike ketamine, did not induce transient or persistent cognitive deficits in normal mice. Further, rapastinel, but not ketamine, as administered here, demonstrated pro-cognitive benefits in a well-studied animal model of cognitive impairment. This difference merits further study in patients who are candidates for rapidly acting antidepressant treatment," said Dr. Herbert Meltzer, a professor of psychiatry at Northwestern Feinberg School of Medicine.

Animal data can help establish safety, but regulators are certain to want to see clear human data before this drug can be marketed. A slate of Phase III studies are being planned for 2016 as Allergan is expected to complete its big merger with Pfizer ($PFE).

Ketamine has inspired quite a bit of R&D work. J&J ($JNJ) is well along with its intranasal version of the drug. On the other end of the scale is Turing, Martin Shkreli's little biotech, which just launched the first clinical study of its own version. And there are clinics around the U.S. which also administer ketamine to patients.

The study was published in the peer-reviewed journal Behavioural Brain Research.

- here's the release