New measurement tool for clinical trials to help children with Charcot-Marie-Tooth disease

An international study led by the University of Sydney and published in the Annals of Neurology has the potential to improve the design of clinical trials for the treatment of Charcot-Marie-Tooth disease, a disorder which affects the peripheral nervous system.

Charcot-Marie Tooth disease (CMT) is among the most common inherited neurological disorders, affecting one in 2,500 people. Symptoms such as leg weakness, foot pain, trips and falls develop in the first two decades of life, with some patients wheelchair bound by 21 years. Currently there is no treatment for any form of this disease, but clinical trials are increasingly occurring.

“While it is very positive that clinical trials are taking place in this area, it is vital that trials are based on appropriately selected patients and carefully chosen outcome measures,” says Associate Professor Joshua Burns, Chief Investigator from the University of Sydney and The Children’s Hospital at Westmead. “This relies on being able to measure disease severity accurately, and in turn the patient’s response to treatment, which we were previously unable to do in children.”

In response, Associate Professor Burns and colleagues from the USA, UK and Italy designed the CMT Pediatric Scale (CMTPedS), a patient-centred multi-item rating scale of disability for children with CMT.

“Rating scales used for adult patients are inappropriate for children and since most forms of CMT affect children there was an obvious need for a new clinical tool.”

“Furthermore, it is during childhood that we anticipate that treatments for CMT may be most effective – before the disease progresses and makes repair more difficult.”

During a 14-month test period the CMTPedS was administered to more than 170 children aged three to 20 with varying types of CMT in Australia and internationally via the Inherited Neuropathies Consortium. Analysis of these data supported the viability of CMTPedS as a reliable, valid and sensitive global measure of disability for children with CMT from the age of three years.

The CMTPedS can be completed in 25 minutes and will have broad application in clinical trials of rehabilitative, pharmacological and surgical interventions.

“There is growing international support for the rating scale to be implemented as the primary outcome measure in studies of children with CMT because the quality of the measure has the potential to influence the outcome of clinical trials and patient care,” says Associate Professor Burns.

This research was supported by grants from the National Health and Medical Research Council of Australia, the National Institutes of Neurological Disorders and Stroke’s Office of Rare Diseases, the Charcot Marie Tooth Association, the Muscular Dystrophy Association and the CMT Association of Australia.