Zolgensma: Baby with spinal disorder recovering well after receiving dose of 'world's most expensive drug'

A 16-month-old baby with a spinal disorder is doing well in recovery after receiving one of the world's most expensive drugs.

Baby Marley became one of the first 30 to receive the newly licenced US gene therapy drug, Zolgensma, at Sheffield Children's Hospital on Tuesday after being diagnosed with spinal muscular atrophy (SMA).

The treatment has been called the most expensive drug in the world - with a list price of £1.79m per dose.

It was made available on the NHS after the health service struck a deal with manufacturers Novartis Gene Therapies in March.

Until two years ago, no treatment options were available for children with the condition, meaning most would die within two years of diagnosis.

Marley underwent the one-off gene therapy infusion after his parents tirelessly fought for his access to the drug.

Parents Rosie-Mae Walton and Wes Powell - who live in Driffield, East Yorkshire - said they are "overwhelmed" after Marley finally got the treatment.

Ms Walton said: "As soon as we found out that it came to the UK, we just cried our eyes out. Then, when we got the antibody test, and that came back negative, that he was eligible for Zolgensma, I read the email and we just cried again.

"It was just the happiest moment ever... just to know that he's actually getting it, after all the time waiting and how much we've been through and how much Marley's been through."

She said Marley appears to be doing really well since Tuesday's treatment, adding: "It feels so surreal, like it hasn't hit home yet that he's actually had it - that a drip is just so expensive and has worked wonders."

Babies born with Type 1 SMA - the most common form of the condition - experience progressive muscle weakness, loss of movement and difficulty breathing.

But studies have found that a single Zolgensma treatment can help babies with the condition to sit, crawl and walk, and also prevented them from having to be put on a ventilator.

The specialist NHS centres across England that can now administer the treatment are Sheffield, London, Manchester and Bristol.

Tony Hart, consultant paediatric neurologist at Sheffield Children's Hospital, said: "Zolgensma is a breakthrough because it really is a miracle drug.

"Without Zolgensma, most children would have died."

In May, five-month-old Arthur Morgan became the first patient in England to be treated with Zolgensma at Evelina London Children's Hospital in London.