UK boy with spinal muscular atrophy walks after gene therapy

A five-year-old boy who was one of the first in the UK to receive gene therapy for spinal muscular atrophy (SMA) is now able to walk.

Edward was diagnosed with SMA at two months old: before the gene therapy Zolgensma was approved for use by the NHS in March 2021 (see BioNews 1087). However, by the time Zolgensma was approved, he was older than six months, above the age cut-off suggested by guidelines. In the meantime, he received Spinraza, another SMA treatment that can slow progression of the disease, and within a few months, he was approved for, and received, the gene therapy.

Edward may still need a wheelchair, but can walk short distances. 'We just didn't think that was possible. We didn't know what quality of life he would have,' his mother told the BBC, who added that he goes to school and 'does everything an ordinary five-year-old boy does.'

SMA is a degenerative genetic condition which causes muscle weakness, affecting movement and breathing. Around one in 40 people in the UK are carriers of a faulty SMN1 gene, but only people with two non-functional copies are affected. In the UK around 65 affected babies are born each year, and without treatment, most would die by age two.

Neither Zolgensma nor Spinraza can reverse muscle damage that has already occurred in children's muscles, which is why treatment should be administered as soon after birth as possible.

Pop singer Jesy Nelson has recently said that her twin daughters have SMA. 'After the most gruelling three, four months, and endless appointments, the girls have now been diagnosed with a severe muscular disease called SMA type 1,' she said in a video posted to social media.

Nelson's daughters were assessed at Great Ormond Street Hospital in London, and have now received gene therapy. However, she explained that neither she nor their doctors were initially concerned that they were not meeting milestones, because of the fact that they had been born prematurely. Consequently, it took several months to get a diagnosis. She has been told that because of the delayed diagnosis, the girls will have some level of disability and may not be able to walk.

Nelson called for SMA to be added to the newborn screening programme, as currently only children with an affected sibling are screened. SMA is one of the conditions that is reported to families who choose to take part in the Generation Study, where newborns receive whole genome sequencing (see BioNews 1210).