Girl, 11, with Rare Childhood Blindness Condition Becomes Second Person in World to Have ‘Revolutionary’ Treatment

An eleven-year-old girl from North Acton, London, has marked a significant milestone in medical history by becoming the second recipient worldwide of an innovative retinal gene therapy designed for patients suffering from Bardet-Biedl syndrome (BBS). Catherine L’Estrange, who has dealt with the full brunt of this rare genetic disorder since infancy, received the treatment in March at St Helier Hospital in Sutton, south London.

Bardet-Biedl syndrome affects approximately one in 150,000 infants and can lead to almost complete vision loss by the time individuals reach their late teens. The condition is a result of genetic mutations that lead to various complications, including visual impairment, weight gain, kidney issues, and physical anomalies, such as polydactylism—having additional fingers or toes. The deteriorating effects on the retina can render those with BBS profoundly visually impaired as they grow older.

Catherine’s challenging journey began when she was diagnosed with BBS as an infant. Over the years, she experienced increasing visual challenges, first becoming night-blind and colour-blind, before ultimately losing much of her peripheral vision. The recent gene therapy aims to introduce healthy copies of the BBS10 gene directly into her retina, which is crucial for the survival of retinal cells, thereby potentially slowing or halting her vision decline.

Reports suggest that the retinal gene therapy is particularly tailored for patients with mutations in the BBS10 gene, which is one of over twenty genes involved in BBS. The groundbreaking procedure performed on Catherine involved removing a gel-like substance from her eye before injecting the healthy gene copies to restore cellular function in her retina. Consultant eye surgeon Neruban Kumaran, who was involved in the procedure, stated that the primary goal is to stabilise vision, and while some patients have reported improved night vision, results may vary for each individual.

Kumaran expressed his cautious optimism regarding the therapy’s potential. He noted that, while perfect vision cannot be guaranteed, the aim is to improve the quality of life for patients in a substantial way. Initial feedback from other recipients of the treatment has been encouraging, giving families newfound hope in dealing with the complexities of BBS.

Catherine herself holds high hopes for the outcome of the treatment, expressing her desire to continue reading the books she loves as well as to retain her vision of the world around her. Her father, the Reverend Timothy L’Estrange, shared his cautious enthusiasm about the therapy, noting that they had not anticipated such advanced gene therapies would be available during Catherine’s childhood, especially since most children with BBS are not diagnosed until later in life. Thanks to Catherine’s early diagnosis, the family felt fortunate to explore this treatment option.

Timothy further commented on the family’s efforts to foster Catherine’s independence and resilience in light of her vision challenges. The development and availability of this revolutionary treatment have been a pleasant surprise for them, presenting an opportunity to change Catherine’s life profoundly and enable her to maintain sight for as long as possible.

The success of this pioneering therapy, designed to combat the typically progressive nature of Bardet-Biedl syndrome, represents not just a medical breakthrough but also shines a light on the importance of early diagnosis and intervention in childhood genetic conditions. As the healthcare community observes the outcomes of this treatment in Catherine and other young patients, the hope is that this will lead to further innovations and therapies for BBS and similar conditions.

This moment underscores the relentless pursuit of medical science to provide advancements that safeguard and improve the quality of life for those affected by rare genetic disorders. As researchers and clinical teams continue to investigate and refine treatments of this nature, families around the world remain hopeful for further advancements that can harness the power of gene therapy to combat inherited diseases.