Can Covid drug lead to break-through for depression?
But she is even more excited about the prospect that drugs like Dexamethasone could possibly also lead to new treatments for depression – and open up a wider debate around inflammation and its impact on our body and our mind.
In 2018, medical opinion around inflammation was challenged by Professor Ed Bullmore when he published The Inflamed Mind.
Received wisdom suggested there was no link between the immune system and the brain – and that inflammation was simply the body’s biological reaction to aid recovery from harmful attacks like damaged cells or pathogens.
“When I heard Professor Bullmore speak at a conference in 2018, it blew my mind,” says Leigh, who is committed to developing new therapies for neurological conditions.
“Here was someone suggesting a clear pathway between inflammation and the brain – and saying that inflammation could actually be a physical cause of depression.”
Leigh, who has suffered from mental health challenges herself, says: “For so long, there has been a stigma that people with mental health problems need to think differently and somehow it’s just in their mind. I have long firmly believed that depression and mental illness are physical disorders with physical chemical causes just like any other illness.
"The idea that our body may be programmed to respond to injury and inflammation by purposely causing depression just made it all click into place."
The World Health Organisation has identified depression as a leading cause of disability worldwide and a major contributor to the overall global burden of disease – and Leigh thinks drugs like Dexamethasone could be a game-changer.
“For so long, we thought inflammation was a bodily reaction to disease and stress, which helped recovery – but could it work the other way around? Could it be a cause as well as a reaction?
“If so, drugs like Dexamethasone might not just help treat Covid-19, it could lead to new ways of developing treatments for depression – and offer an alternative to the standard antidepressants we have used for 30 years.
“There aren’t many drug trials going on in this area, but I hope this renewed focus on anti inflammatory drugs could encourage more activity.”
Leigh recognises this is a complex area.
“Many victims of Covid-19 have died as a result of a cytokine storm,” she explains. “Put simply, that’s an over-active immune response by the body to the virus, causing severe inflammation of the lungs and other organs. Dexamethasone can control that immune response and prevent some deaths, though it will probably be part of a combination of drugs, including anti-virals.”
The potential for Dexamethasone was highlighted by the Oxford University research team in a pre-print paper, a study not yet reviewed by medical peers and normally not published until validation in a medical journal. However, as Leigh told The Scotsman in May, Covid-19 has given real urgency to the trials process.
“Using a known drug for a new reason – like Dexamethasone for Covid-19 – would class as a ‘re-purposing’ study,” explains Leigh, who is committed to making Caritas a leader in carrying out trials for drugs targeted at neurological conditions. “However, it still has to go through the normal clinical trials process.
“It doesn’t yet have marketing approval for Covid-19 treatment, so it couldn’t be prescribed in the normal way. However, if they saw positive results, doctors might be able to put more of the right kind of patients through trials and might be able to prescribe it off-licence (if the patient or their representative agreed), although this would be at the doctor’s risk if anything went wrong.”
Although the general public might have been shocked a cheap steroid like Dexamethasone could help save lives in the current pandemic, Leigh was not too surprised.
“The fact it was included in the RECOVERY trial suggests they thought it might have an impact,” she says. “People were talking about Ibuprofen and Covid-19 early on, so there was clearly some thinking that anti-inflammatories might have a part to play.”
In terms of anti-inflammatory drugs’ potential to treat depression, Leigh feels the time is right for this conversation - as many people struggle with poor mental health in the wake of Covid-19.
“The long-lasting neurological impacts of the virus really worry me,” she says. “Many people have suffered bereavement, but not been able to grieve properly due to restrictions. Others have struggled with the isolation of lockdown and there will also be significant impacts from large-scale job losses.
“Mental health is the root cause of many physical illnesses and if we do not prioritise it now, we will have to deal with many more long-term physical problems.
“We have a chance, with the dexamethasone breakthrough, to really put a focus on mental health - and we have to seize that opportunity.”
Find out more at www.caritasneuro.com