An 11-year-old girl from North Acton, west London, has made history as the first British individual to undergo groundbreaking gene therapy for a rare condition that typically results in blindness by early adulthood.
Catherine L’Estrange was diagnosed with Bardet-Biedl syndrome (BBS) as an infant, a condition caused by a gene mutation leading to progressive vision loss. To preserve Catherine’s eyesight, surgeons administered healthy copies of the gene directly into her eye, a procedure previously performed on only one other person globally.
Expressing her hopes for the treatment’s success, Catherine shared, “If this treatment works, it will enable me to continue experiencing the world around me, particularly allowing me to read books, which I deeply enjoy.”
BBS, affecting approximately one in 100,000 births in the UK, not only causes vision impairment but also poses risks of kidney issues, learning challenges, obesity, and sometimes extra digits on hands or feet.
The gene therapy, developed by MeiraGTx, involved injecting healthy copies of the BBS10 gene into Catherine’s retina, the light-sensitive tissue at the back of the eye, during an hour-long procedure at St Helier Hospital in March.
Consultant eye surgeon Neruban Kumaran emphasized the significance of the treatment in potentially preserving or enhancing vision for individuals with BBS, underscoring the emotional impact on families striving to maintain their children’s independence amid vision loss.
Collaborating with experts from Great Ormond Street and Moorfields Eye Hospital, the medical team at St Helier identified young patients with the specific BBS10 gene mutation, with Catherine being diagnosed at a remarkably early age compared to most children with BBS.
While the full outcomes of the gene therapy remain to be seen, initial feedback from patients and families has been positive, suggesting potential improvements in vision, particularly in dim light. However, it will take time to ascertain the therapy’s long-term effects.
St George’s, Epsom and St Helier Hospitals Group’s chief executive, Mat Shaw, expressed pride in the hospital’s efforts to offer hope to children and families grappling with the devastating impact of childhood blindness, striving to redefine possibilities for those affected by such conditions.