A five-month-old baby is the first patient in the UK to be treated with a life-saving drug on the NHS which could potentially prolong the lives of children with spinal muscular atrophy.
Arthur Morgan received the one-off gene therapy at Evelina London Children's Hospital on May 25, making him the first patient in England treated with the drug.
Spinal muscular atrophy (SMA) is the leading genetic cause of death for children and until two years ago, there were no treatment options available, according to Wales Online.
US gene therapy Zolgensma is described as being the most expensive drug in the world with a list price of £1.79 million per dose.
The treatment could potentially allow babies to sit, crawl and walk after being treated with the drug.
The NHS made a deal with manufacturers Novartis Gene Therapies in March.
Baby Arthur, who was born six weeks premature in December, underwent the gene therapy infusion last week after being diagnosed with SMA less than three weeks earlier.
His father Reece Morgan, 31, who works as a self-employed plasterer, said: "When we found out that Arthur would get the treatment, and be the first patient, I just broke down.
"It had been such a whirlwind few weeks, filled with lots of anxiety and adjustment, as we learnt about his condition and what it might mean for him and our family.
"We still don't know what the future will hold, but this gives Arthur the best possible chance to give him the best possible future."
Babies born with Type 1 SMA, which is the most common form of the condition, experience progressive muscle weakness, loss of movement, difficulty breathing, and have a life expectancy of just two years.
Studies found that a single treatment with Zolgensma has helped babies with SMA to sit, crawl and walk, and also prevented them from having to be put on a ventilator.
Four specialist NHS centres have now been commissioned across the country to administer the treatment, including Evelina London Children's Hospital, where Arthur was treated.
The other sites are Manchester University NHS Foundation Trust, Sheffield Children's NHS Foundation Trust and University Hospitals Bristol and Weston NHS Foundation Trust.
Dr Elizabeth Wraige, consultant paediatric neurologist at Evelina London Children's Hospital, said: "This treatment will bring hope to families affected by SMA who have fought so courageously against it."
NHS chief executive Sir Simon Stevens added: "It is fantastic news that this revolutionary treatment is now available for babies and children like Arthur on the NHS.
"The NHS Long Term Plan committed to securing cutting edge treatments for patients at a price that is fair to taxpayers.
"Zolgensma is the latest example of the life-changing therapies that the NHS is now routinely using to transform the lives of patients and their families."
Health Secretary Matt Hancock said: "I am so glad young Arthur can access this potentially life-changing treatment on the NHS. I hope it grants his family and many others renewed hope that more children's lives can be transformed."
