Ketamine pill halves depression severity: Study

A new treatment option could be on the way for patients with treatment-resistant depression after a slow-release ketamine tablet was found to significantly improve patient outcomes.
 
The study, which included researchers from the University of New South Wales (UNSW), found the pill was able to reduce depression and relapse incidents, as well as be more affordable and accessible than current alternatives.
 
The slow-release tablet form was designed to be taken safely at home without medical supervision, unlike injectables and nasal sprays which require clinicians to monitor patients after use.
 
For the research, published in Nature Medicine, scientists assigned 168 patients with treatment-resistant depression to one of five groups: four receiving different strengths of ketamine, and one receiving a placebo.
 
Ultimately, the randomised-controlled trial found patients taking the strongest dose of ketamine, 180 mg taken orally twice a week, had the best results when compared to the placebo.
 
Using the Montgomery-Asberg Depression Rating Scale (MADRS), which measures the severity of depressive episodes, they found the 180 mg group had an average score reduction of 14 points from a high of 30.
 
In the placebo group, the average reduction was eight points, and all remaining doses of ketamine – 120 mg, 60 mg and 30 mg – also outperformed the placebo.
 
‘Relapse rates during double-blind treatment showed a dose response from 70.6% for placebo to 42.9% for 180 mg,’ the study also found.
 
‘Tolerability was excellent, with no changes in blood pressure, minimal reports of sedation and minimal dissociation.’
 
UNSW researcher and clinical psychiatrist Professor Colleen Loo labelled the results ‘fascinating’.
 
‘There’s the practical clinical reason that this is a way of administering ketamine to treat depression that’s much easier to give,’ she said.
 
‘Rather than having to come to the clinic and have an injection and have medical monitoring for two hours, once or twice a week, this is much more convenient and allows patients to have their treatment at home.’
 
Dr Cathy Andronis, Chair of RACGP Specific Interests Psychological Medicine, described it as an ‘interesting study’, but said a lot more research is needed to understand how the treatment works.
 
‘We need to know more about its risks and benefits, and the capacity of our health system to manage what is essentially outpatient and unsupervised treatment with a significant risk for misuse and harm,’ she told newsGP.
 
‘It’s important to manage severe depression holistically and to maintain evidence-based practices, it’s also critical to provide high-quality psychological and social support services to these patients.
 
‘They deserve excellent, quality care even more than expedient unsupervised treatment.’
 
Researchers also said dissociative effects have previously been thought of as integral to improve depression with ketamine, but this was not experienced with the slow-release tablet form.
 
‘That’s because only a tiny amount is released into the bloodstream at a time, with ongoing slow release over days, and you don’t experience the dissociation at all, and yet people are improving,’ Professor Loo said.
 
‘So it could be that the theory you must have these altered reality perceptions to improve may not be correct.’
 
The new research follows a study released last year which found a low-cost ketamine injection had a 10-fold treatment advantage for patients compared with placebo medication.
 
Dr Andronis said she would support its introduction into general practice, but only as part of holistic quality care.
 
‘The danger is that commercial imperatives often override safety and quality,’ she said.
 
‘A good GP can supervise and monitor to ensure that a patient receives the best individualised care that they need.’
 
It is now hoped a double-blind trial for the treatment can be carried out in the future, ahead of the drug potentially be approved by the Therapeutic Goods Administration.
 
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depression ketamine mental health