According to an article published March 15, 2018 in the Journal of Psychopharmacology, a pilot trial of intranasal ketamine for the treatment of severe depression conducted by researchers from the University of New South Wales (UNSW) and the Black Dog Institute was suspended due to poor tolerability.
The trial was halted after the first 5 patients dosed experienced acute side effects such as “psychotic-like effects,” high blood pressure, and motor coordination problems severe enough that patients lost the ability to operate the spray device well enough to deliver the entire dose. Each patient was meant to self-administer the treatment as a series of 10 sprays at 5 minute intervals, with a total of 8 treatments over a 4-week period.
The researchers placed the blame in part on inconsistent absorption from patient to patient, which led to some patients having high peak levels of ketamine and concluded, “IN ketamine, with the drug formulation and delivery device used, was not a useful treatment approach in this study.”
UNSW Professor Colleen Loo, the study’s lead author said, “It’s clear that the intranasal method of ketamine delivery is not as simple as it first seemed. Many factors are at play when it comes to nasal spray ketamine treatments. Absorption will vary between people and can fluctuate on any given day within an individual based on such things as mucous levels in the nose and the specific application technique used.”
Loo and her team are now recruiting for a trial of ketamine delivered by subcutaneous injection.
In December 2017, Janssen published positive results from a Phase 2 study of intranasal esketamine for the treatment of depression in JAMA Psychiatry, and that product is currently in Phase 3 development.
Read the Journal of Psychopharmacology abstract.
Read the UNSW press release.
