Hope for Duchenne sufferers around the world

16-year-old Billy Ellsworth is still walking thanks to Western Australian researchers who developed the first drug to address the underlying genetic defect of Duchenne, and the first of its type to be approved by the US Food and Drug Administration (FDA).

In September 2016, the FDA granted accelerated approval of Exondys 51, which was developed by Perron Institute Director Professor Steve Wilton and his long time collaborator Professor Sue Fletcher and their team based at Murdoch University. The drug has drastically improved the health and wellbeing of Duchenne muscular dystrophy (DMD) sufferers during clinical trials.

Billy was born with DMD; a fatal childhood condition that typically leads sufferers, usually boys, confined to a wheelchair before 12 years. Billy and his mother Terri have travelled from Pittsburgh (USA) to Australia for the first time to spend time with the researchers bringing new hope to Duchenne suffers around the world.

“We never thought Billy would still be walking at 16 or be as self-sufficient and independent as he is today. His treatment has been life altering and gives hope to the future,” said Terri Ellsworth, Billy’s mother.

Professor Wilton, Director of the Perron Institute and Foundation Chair in Molecular Therapies at Murdoch University, said Billy is a remarkable young man whose courage and determination is inspiring.

“At the age of 11, Billy was unable to walk down a small bush incline in his hometown in Pittsburg without someone either side to stabilise him. Two years after starting the treatment, not only was Billy able to walk independently down the same path at a time when he should be in a wheelchair, his breathing has been stabilised and he can whistle as he walks up hill,” said Professor Wilton.

“In fact, his mobility and breathing improvement enabled Billy to complete the 2015 Pittsburg Children’s Marathon.”

Professor Fletcher, Deputy Director of the Centre for Comparative Genomics at Murdoch and Director of Research at the Perron Institute, said Exondys 51 is not a cure; it rescues some dystrophin expression and reduces the severity of the disease.

“Loss of the ability to walk is a significant milestone in the progression of the disease, so keeping boys on their feet is crucial,” Professor Fletcher said.

“If we can keep boys moving, keep them upright, this reduces contractures, improves breathing and maintains independence and the health and wellbeing of these kids.”

Professor Wilton said the reason he and Professor Fletcher got into medical research is to try to make a difference.

“For more than two decades, we have tried to look at ways to give the body the ability to minimise the muscle wasting caused by DMD,” he added.

“Exondys 51 is the first dystrophin restoring drug that has shown a modest but unequivocal increase in the missing protein, dystrophin, after treatment. The fact that our work has enabled boys like Billy to have a better quality of life, fuels our fire to forge ahead and make a positive difference to other suffers around the world.

“We hope Exondys 51 is going to be the first of a new type of genetic drug. With more than 7,000 inherited diseases, there is the potential for this type of therapy to be applied to many other genetic conditions.”

Ongoing Murdoch University and Perron Institute research is applying the ‘genetic patch’ technology developed for Duchenne to other diseases such as spinal muscular atrophy, the most common genetic cause of death in children under the age of two years, Pompe’s disease and other types of muscular dystrophy.

Steve Arnott, CEO of the Perron Institute said: “We are thrilled to meet Billy and his mother Terri in WA where the process began. We are also proud to see decades of dedicated effort create positive outcomes in translational research and benefit young people like Billy.”

Image courtesy of Murdoch University.