Pioneering Trial Offers New Hope for Epileptic Dogs, Says Study
A groundbreaking, first-of-its-kind clinical trial in dogs could offer new hope for pets and their owners impacted by canine epilepsy.
Led by researchers at the University of Glasgow’s Small Animal Hospital in collaboration with the Royal College of Surgeons in Ireland, the METriC (MiRNA-134 -antisense-oligonucleotide Epilepsy Treatment in Canines) trial, hopes to successfully treat dogs with severe epilepsy with a new medication, Ant-134. So far, results from the trial have been encouraging, with some of the dogs experiencing a reduction of symptoms and an improved quality of life.
Canine epilepsy is the most common neurological disorder in dogs, causing debilitating and life-changing symptoms for both dogs and their owners. The condition affects just under 1% of all dogs in the UK, estimated to be around 1 in 130 dogs. In most cases canine epilepsy is a lifelong disease, and while some cases can be managed with medication, other animals respond less well to treatments, or not at all. Sadly, up to one third of epileptic dogs do not respond to anti-seizure medications, impacting their health and quality of life, and causing owners significant levels of anxiety. Dogs with untreatable epilepsy can suffer dozens of seizures in a month, sometimes ending in stays in animal hospital ICUs.
The METriC trial will use a new medication – never used in dogs or humans – to help treat some of the sickest dogs with epilepsy. To do this the clinical trial team are trialling the drug Ant-134 to ‘silence’ a molecule called miRNA-134, known to be implicated in epilepsy. Silencing miRNA-134 is thought to produce neuroprotective effects in the brain, suppressing epileptic seizures and controlling the condition. Initial results in mice have showed long-lasting seizure control with no side effects.
Led by Dr Rodrigo Gutierrez Quintana, senior university clinician in veterinary neurology, METriC is a voluntary, randomised double blinded placebo-controlled study. Half of the dogs on the trial will receive Ant-134 while also receiving their prescribed conventional medications, while the other half will receive a placebo and remaining on their prescribed medications. Dogs that receive a placebo will be offered the Ant-134 in an open-label phase at the end of the study period. Dogs can only be enrolled onto the trial if they meet a set of criteria, including no or poor response to conventional medication, and with a referral from their vet.
Dr Gutierrez Quintana, said: “Some dogs suffering from canine epilepsy can be very difficult to treat, affecting the dog’s quality of life, and causing distress and frustration for owners and veterinarians. For this reason, we decided to organize the METriC trial, to try and find a new way of treating epilepsy that could help these dogs and their owners.
“We are still in an early phase of the trial, but so far we have observed very good responses in some of the dogs treated with Ant-134. Our findings so far support continuation of the trial, and we are keen to continue recruiting dogs to further this important research.”
Rob and Dianne Hewgill, from the Peak District, enrolled their dog Oscar – a 7-year-old golden cavalier (a cross between a golden retriever and a King Charles spaniel) – in the trial last spring after exhausting many normal, conventional medication options to treat the epilepsy that Oscar had suffered from since he was an 18-month-old pup.
So far, Oscar has had two treatments on the trial and is responding extremely well.
After the first treatment Oscar didn’t have seizures for three months; and since the second, slightly stronger dose administered last September, after a two-week period adjusting to the increased dose, Oscar has been back to normal and seizure free. How long that may last is still unknown and is one of the questions the trial aims to answer.
Prior to joining the trial Oscar wasn’t doing well. His epilepsy started gradually, initially only one seizure every month or so, but later the condition progressed and became more frequent and harder to manage, with ever increasing levels of medication being needed. The spells of normality between seizures – maybe six weeks at most – became shorter, and by the time Oscar joined the trial he was on the highest levels of 4 different types of pills that could safely be given to control his focal epilepsy episodes without developing long term toxic complications. Oscar’s quality of life, as well as that of Rob and Dianne, whose work and home life were being extremely affected, had reached crisis point. The focal seizures, once they took hold where they could increase frequency to every 10 minutes over a few hours, were very difficult to stop and required 3 to 4 days sedation in the vets’ ICU to ‘reset’ his brain and stabilise his health.
Looking back, Dianne recalls how the couple felt desperate. She said: “The difference from how Oscar was before treatment to now is amazing. Our local vet suggested the trial and, to be honest, it sounded promising. We had nothing to lose at that point and thought it was worth a try. And it has been incredible to see Oscar – who is otherwise healthy – be back to being a normal and happy dog; it’s been a revelation.”
Rob added: “We weren’t expecting such a significant result and tried more out of hope than anything, but it’s been a huge relief and an improvement in quality of life for Oscar and us. The Glasgow vets provide us with updates on the progress of the trial at each visit, which helps us understand the overall progress and learning this trial is providing, and Oscar receives regular check-ups, which is reassuring to have monitoring of Oscar’s ongoing health.”
Dianne added: “If we hadn’t got Oscar on the trial, he 100% wouldn’t be here, so we are very grateful for the opportunity and all the hard work the Glasgow University team have put in to make the trial a reality – it’s been life changing.”