Drug hope for young victims of muscular disease

For the first time, research has shown it is possible to counteract the effects of Duchenne muscular dystrophy (DMD) throughout the body.

Seven out of 19 young patients aged five to 15 responded to the injected drug in an early-stage clinical trial.

DMD is an hereditary disease that affects one in 3,500 newborn boys, with around 100 new cases diagnosed in the UK each year.

It is marked by the lack of dystrophin, a vital muscle protein, leading to the progressive breakdown of muscle cells.

By the age of 12, boys with the disease become unable to walk and by the late teens or early 20s the condition may become life threatening as breathing is compromised.

While not providing a cure, the treatment has the potential to reduce the symptoms of DMD enough to prevent severe disability and allow a reasonable quality of life.

Dr Marita Pohlschmidt, director of the Muscular Dystrophy Campaign, said: “We have fought to find a treatment for this devastating condition for the past 50 years.

“Today we can say with real confidence that we’re going to win that battle. Parents of these boys can have real hope for the future.”

The “antisense” drug is a synthetic form of the genetic chemical RNA. It acts as a “molecular patch” covering over a section of garbled instructions in the genetic code and allowing two working sections to be joined together.

“If you cut the Golden Gate bridge in half it will collapse; that’s the kind of problem we’re talking about,” said study leader Prof Francesco Muntoni, from the Institute of Child Health in London. “These molecular patches allow the two sides of the ‘bridge’ to come together.

“This is the first time that a drug or genetic therapy has had a systemic effect in DMD so that every muscle is targeted. Every other study has involved injection treatments that target a single muscle.

“These are very exciting results that prove the case for an even more detailed look at this genetic therapy.”

He said the drug was well-tolerated, with no major side effects detected.

Three of the boys given higher doses of the drug had their dystrophin restored to levels up to 18 per cent that of normal muscle.

The study only monitored the patients for 12 weeks, but a new trial planned by Prof Muntoni’s team will follow the progress of around 20 boys for two years.

Results of the Medical Research Council-funded trial are published online in The Lancet medical journal.