A baby boy has the chance of a "normal" life after a one-off dose of the "most expensive drug in the world" which took one hour to administer and cost £1.8m.

Parents Rosie-Mae Walton and Wes Powell, from Driffield, fought for their son Marley, 16 months, to get the treatment which could transform his future, following his diagnosis of Type 1 spinal muscular atrophy (SMA).

Marley had the "miracle" treatment at Sheffield Children’s Hospital on Tuesday afternoon and is now recovering.

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Ms Walton said it had been a “rollercoaster” since the drug, Zolgensma, was licensed in March, as they waited to find out whether Marley was eligible.

He had to have an antibody test first to ensure he was eligible, while his parents had a tense wait for the results.

She said they just cried when he was finally approved.

The £1.8 million "miracle" drug used to treat Marley
The £1.8 million "miracle" drug used to treat Marley

Speaking to Hull Live after the treatment, Rosie-Mae said: "We feel amazing that Marley has had the treatment.

"Marley is currently doing amazingly after his treatment. We were unsure at first if he was going to be eligible for Zolgensma so when we found out he was and the antibody test came back negative we just cried and cried with happiness all day, because we finally knew he could have it.

"This drug is the most expensive drug in the world and he deserves it."

SMA is a genetic condition which causes a range of life-limiting problems, meaning that most children with the condition die within a couple of years.

Rosie-Mae added: "Zolgensma could give Marley the possibility to sit unaided and even walk. It's such a surreal feeling knowing he's had it because it's just a one-time treatment and you just connect it to a drip over one hour and it's done.

“It was just the happiest moment ev, 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.

“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.

“It’s just crazy considering all we’ve been through and the amount of scares you get put through thinking that your baby won’t reach the age of two or a second birthday.

Parents Rosie-Mae Walton and Wes Powell, from Driffield, with baby Marley
Parents Rosie-Mae Walton and Wes Powell, from Driffield, with baby Marley

“Then you think that he’s had this most expensive drug in the world. It’s just crazy. It’s the best thing ever.”

The couple said money raised for Marley will be used for continuing treatment, including private physiotherapy and equipment.

Rosie-Mae said: “As much as he’s got his treatment, it’s not just going to be an easy ride. So, we just thank every single person that’s helped out for that.”

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.”

He said Zolgensma stops further deterioration but more research is needed to know whether it can repair existing damage.

But he said some children who have had the treatment do appear to have got stronger.

Mr Hart said more than 30 children have now received Zolgensma in the four centres in England and Wales where is it being given – Sheffield, London, Manchester and Bristol.

Asked about handling the “most expensive drug in the world”, the consultant said he leaves that to the nurses, adding: “One of the great things about the NHS is that decisions about costs are taken out of our hands and our priority is giving as many children who need it the drug when we can, and as fast as we can.”

NHS England announced in March that it had struck a “landmark confidential deal” with US-based manufacturer Novartis Gene Therapies which then-chief executive Sir Simon Stevens described as a “life-changer”.

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.

Rosie-Mae added that the family would like tot hank everyone for their support: "We are so overwhelmed by all the love and support we have received from people.

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"We did the fundraising for Marley before we knew he could have Zolgensma treatment and we thank every single person that has donated or shared the fundraiser and that money will now go towards the cost of equipment and private physiotherapy for Marley.

"Even though Marley has had the treatment there is still a long road ahead."

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