Please login to the form below

Could ketamine be the next big thing in depression?

Account Executive Will Frostick discusses the established treatment model for depression and its limitations, as well as a new entrant poised to revolutionise the field – ketamine.
Depression is a leading cause of disability worldwide and with more than 1 in 10 suffering from symptoms, it is likely to affect many of us in some way over our lifetimes.However, despite the large public health burden of depression, therapeutic discovery in this field has lagged significantly behind other areas of medicine and our ability to combat depression and relieve its symptoms is limited.

Antidepressant treatment: a history

For the last 50 years, antidepressant research and medicine has been dominated by the monoamine hypothesis. This theory links depression to the depletion or perturbation of signals from certain neurotransmitters, such as serotonin and norepinephrine, whose chemical structures belong to a class of molecules known as monoamines.The theory suggests we can reduce depression by stn ever since.Like many scientific breakthroughs, the monoamine hypothesis was found by chance. Doctors noticed that tuberculosis patients treated with isoniazid showed signs of improved mood.Isoniazid is antituberclular but it also interferes with monoamine metabolism, slowing neurotransmitter breakdown once it is released. As a result, more monoamines are left active in the brain for longer periods of time. It was also observed that reduced monoamine levels could predict suicidality.Based on this evidence, the monoamine hypothesis has risen to the forefront of depression science.

Stagnation, stagnation, stagnation

Since the isoniazid discovery, an abundance of antidepressants based on the monoamine hypothesis have entered the market.While there is some variance in the molecular mechanism, these drugs still work on the same general principle. For example, Prozac (fluoxetine) is a selective serotonin reuptake inhibitor, or SSRI.SSRIs inhibit brain cells’ natural process of ‘vacuuming-up’ (reuptake) a specific monoamine (serotonin). Much like isoniazid, this has the overall effect of increasing the amount of monoamine left hanging around (see figure above).This general model has been used to treat millions of patients and was the first major breakthrough in depression medicine. However, there has been little to revolutionise the field in the half century since.Nearly all the treatments entering the market have been ‘me too’ drugs, and while second generation therapies have demonstrated improved tolerability and more specific biological actions, the approach has failed to generate notably more effective therapies.Response rates have stagnated over the years and tricyclic clomipramine, one of the oldest antidepressant drugs, remains one of the most effective.

What are we missing?

There is more to be concerned about than inertia. Although antidepressants reliably increase neurotransmitter levels in the brains of patients, this does not always translate into symptom relief.Response rates are often only marginally greater than placebo, and much of the symptom relief can be linked to an active placebo effect. Even though neurotransmitter levels rise within hours, it can take 4-6 weeks to see any therapeutic benefit (although not to see the side effects). Further still, pharmacological depletion of monoamines in healthy volunteers does not cause depression either. These criticisms call into question the presumption that depression is caused by an impairment of monoaminergic neurotransmitter function. This clearly suggests the monoamine model is insufficient. Limited efficacy combined with painstakingly long onset times are letting down vulnerable patients. Fortunately, a new approach is emerging and excitement is building about “the most important breakthrough in antidepressant treatment in decades”. Ketamine as a depression treatment may seem unorthodox to some but the early results are remarkable.



Download the full article from Blue Latitude Health

3rd August 2017

Share

Tags

Company Details

Blue Latitude Health

+44 203 328 1840

Contact Website

Address:
Blue Latitude Health (UK)
140 Aldersgate Street
London
EC1A 4HY
United Kingdom

Latest content on this profile

Precision medicine from concept to clinic
In our latest edition of ‘Perspective’ magazine, we examine the challenges and opportunities for several stakeholders impacted by the dawn of precision medicine
Blue Latitude Health
The problem with the ‘recovery’ conversation in mental health
Account Executive Loredana Gogoescu discusses the impact our language can have on people experiencing mental illness, and asks if terms such as 'recovery' are appropriate.
Blue Latitude Health
'Fake news': battling misinformation in healthcare
Blue Latitude Account Executive Ford Stewart explores inaccurate reporting of healthcare innovations and the consequences of fake news for patients, healthcare professionals and the public.
Blue Latitude Health
50 questions for delivering an exceptional healthcare brand experience
Our 50-question brand planning checklist for healthcare ensures you deliver an exceptional experience, based on what your stakeholders want and need
Blue Latitude Health
The brand strategy revolution
Introducing a new tool for developing a stakeholder-centric brand, based on the experience your patients and their HCPs want and need.
Blue Latitude Health
How Medisafe is using AI to improve patient adherence
Dina Patel speaks to Omri Shor, Co-Founder and CEO of Medisafe, to find out how his medication management app is tackling the problem of poor adherence.
Blue Latitude Health