How Ketamine Could be a New Depression Treatment in Aotearoa

NEWS | DRUGS

Written By Amani Sadique (she/her) | @amani.sadique | Contributing Writer

Researchers at the University of Otago have recently proven ketamine to be successful in reducing depressive and anxiety symptoms in patients with treatment-resistant depression (TRD), and are now recruiting patients in Te Waipounamu to participate in a new trial of the drug.

Medsafe has yet to approve ketamine as a treatment for depression and Pharmac does not subsidise ketamine in any form as a treatment for depression.

Group Manager of Medsafe Chris James said "It is important to note that for Medsafe to consider a medicine for approval for a specific treatment, or 'indication', a pharmaceutical company must make an application. An application would include data demonstrating clinical efficacy and safety, generated through clinical trials.

"No Pharmaceutical company has yet applied for approval for a ketamine-based medicine to be used for TRD."

Pharmac's Manager of Pharmaceutical Funding Adrienne Martin said the company hadn't received a funding application for ketamine for depression.

"Pharmac has received three funding applications for a similar medicine, esketamine for TRD. Based on the clinical advice received, two of these applications have been proposed to be declined.

"We have a third application for esketamine for TRD, post augmentation, where an individual has tried many or all treatment options available. This was reviewed by clinical experts on our Pharmacology and Therapeutics Advisory Committee (PTAC) in February 2024. PTAC recommended this funding application be declined.

"Ketamine is funded in hospitals without restrictions which means it can be prescribed by a clinician for any relevant use. This means it may be used for depression, but Pharmac does not have data on what clinical indication ketamine may be being used for."

Researcher and Senior Lecturer in the Department of Psychological Medicine at the University of Otago Dr Ben Beaglehole said ketamine treatment is offered by some healthcare providers in Aotearoa.

"The Royal Australian and New Zealand College of Psychiatrists has a position statement about ketamine and makes recommendations about how it should be used by mental health services.

"Es-ketamine (Spravato), a close relative of ketamine, is already licensed in Aotearoa but is not funded and is very expensive. There is also a limited amount of ketamine treatment occurring privately in Tauranga and in the public system.

"More widespread use of ketamine is probably dependent on several factors including clinician training/expertise, the results of longer-term studies, and the arrival of tablet formulations as most ketamine studies use injectable ketamine which is not feasible for widespread use."

The Otago researchers’ report published in January said "The rapid-onset activity of ketamine on symptoms of anxiety and depression in patients with TRD has been reported from multiple research groups (Bahji et al., 2022; Johnston et al., 2023), so the positive mood responses in this paper are unsurprising.

"As expected, we have confirmed ketamine's antidepressant and anxiolytic activity in patients with TRD."

Their new study aims to see if adding behavioural activation therapy prolongs the benefits of a course of ketamine treatment, as their findings showed symptoms were only reduced for up to a week after treatment. 

Half of the participants of the trial will take part in an eight-week course of ketamine alone, whilst the other half will receive ketamine in conjunction with behavioural activation therapy.

Behavioural activation therapy is a type of psychotherapy which aims to reduce symptoms of depression by increasing activities that improve mood and overall well-being.

The researchers expect the trial to conclude by mid-2026, or when 60 participants have completed the trial. So far, it has recruited 12 out of 60 participants.

Otago researchers are also interested in the benefits of ketamine for other indications.

"We are in the early stages of applying for grant applications to assess the benefits of ketamine for other health problems such as Alcohol Use Disorder," Beaglehole said.

However, Beaglehole has concerns that using ketamine for medical reasons would increase its use recreationally.

"My impression is that harms associated with ketamine are likely to be less than with amphetamines, much less than with alcohol, it's probably less likely to cause a psychotic illness than cannabis, but I suspect there will be some harms associated with wider use of ketamine as a treatment. When that occurs, the benefits have to outweigh any harms for it to be used clinically."

Beaglehole shared he thinks the social idea of drugs being "nasty" is a "social phenomenon," and that classing drugs as legal or illegal isn't the right way to go.

"I think it's better to think about drugs as having therapeutic and harmful qualities.

"If a substance has therapeutic qualities that need to be researched and explored, I think that should be done. If enough research suggests that it's got benefits as a medicine, I'd prefer it to be available."

The NZ Drug Foundation has said there are no moves to decriminalise ketamine in Aotearoa, but there are moves afoot in several American states to decriminalise possessing or using ketamine as part of a wider move to decriminalise the use of psychedelic drugs. 

A media release published by the foundation in June suggested that significant boosts to funding are needed in Aotearoa if we want a health-based approach to drug use.