It is hoped a treatment for disabling tremor, commonly seen in Parkinson’s disease but also many other conditions, using botulinum toxin injections (Botox™, Dysport™, or Xeomin™) will help people across Australia who live with the condition.
A study is underway at Westmead Hospital to assess how well Botulinum Toxin injections, ease the symptoms of tremor in the muscles around the shoulder and elbow.
The study is being led by Dr Victor Fung, who is Clinical Associate Professor at Sydney Medical School, The University of Sydney and the Director of the Movement Disorders Unit at the Department of Neurology, Westmead Hospital.
“Tremor is a very common neurological problem, it affects five to six per cent of people over the age of 70 but it can actually appear at any age and there is a large unmet clinical need in terms of treatment for tremor,” Dr Fung said.
“Over 75 per cent of people with tremor will experience some sort of disability from that tremor and the disability affects day-to-day life … things such as eating, drinking, the ability to put on make-up, do up buttons, activities such as playing golf, or writing.”
The study, a Research and Education Network (REN) clinical trial, commenced in July 2017 and involves 15 people who receive injections.
There have been a number of attempts at using botulinum toxin to treat tremor, most of which have involved treating muscles in the forearm, however the results have been disappointing, failing to translate into improved function and increased quality of life.
“So what we’re doing differently with this tremor is we’re really focusing on disabling tremor that is generated from muscles around the shoulder and elbow and those muscles can basically be injected more successfully, finding a balance between making those muscles weak enough to dampen tremor without making them so weak to cause disability,” Dr Fung said.
Tremor is very difficult to treat effectively with medications and the only other options open to people are surgical treatments.
However, the use of botulinum toxin has opened up a new range of possibilities.
“Before we commenced this randomised controlled study we were one of the first centres to actually use this treatment open label to have a look-see, to see whether it might be helpful or not,” Dr Fung said.
“So this study is to try to give some definitive proof, then it can be used hopefully to advocate for funding of this treatment on a wider scale for people not just in our institution but in the wider community as well.”
Former school teacher Philip Webster, 74, was diagnosed with Parkinson’s disease three years ago.
“I noticed my hand trembling, my fingers particularly trembling and my arms starting to shake,” he said.
Philip, who had taught writing, found he could no longer put pen to paper.
“Now I’ve been part of this trial I’ve noticed an improvement since the injections,” he said.
“I’ve now been able to take notes, been able to write a sentence – slowly – it’s not as fluent as it used to be, but it’s much better and that has been one of the major improvements.”
Botulinum Toxin is a neurotoxin, which disables the engine nerve that talks to the muscle.
By injecting botulinum toxin into a muscle it stops the nerve communicating with the muscle effectively and that makes the muscle weak.
“So what we’re doing with some of the tremor, is we’re trying to identify what are the main muscles that are actually driving that tremor,” Dr Fung said.
“We inject those muscles to weaken them whilst leaving the good muscles alone.
“Many people actually have shoulder or elbow tremor as being the main problem, so there is a significant group of people that stand to benefit from this treatment,” he said.
The study period for each person is six months, with the last three people to be injected in the next few months.
“There are people within the study that are reporting that they did experience benefit,” Dr Fung said.
“People will report that, for example, they are able to feed themselves more easily, they are able to cut their food more easily, they are able to drink from a full or near-full cup as opposed to not being able to drink from a cup at all.
“And from our previous experience we are hoping that two out of three people at least will experience some sort of benefit.”
Philip said he felt lucky to be part of the study and that it had been a life-changing experience.
“I can still putt, which is the most important part of the whole issue,” he added.
Botulinum toxin started out as a treatment for muscle spasms in the face and the neck.
It has since become a treatment for disorders involving migraine, excessive sweating, urinary incontinence and swallowing.
“In people that we’ve injected in the past we’ve certainly had people be able to, for example, go from not being able to eat breakfast themselves for years to being able to eat breakfast themselves again,” Dr Fung said.
The study includes personalised goals and functional benefits as the main outcome measure rather than simply measuring whether a tremor reduces.
“At the end of the day what’s really important is whether that reduction in tremor translates into a reduction in disability,” Dr Fung said.