Spark Therapeutics’ Luxturna nears FDA approval for gene therapy treating inherited blindness

In a significant development in gene therapy, Spark Therapeutics’ Luxturna (voretigene neparvovec) is on the verge of receiving FDA approval for treating blindness caused by inherited retinal diseases (IRD), specifically those mediated by the RPE65 gene mutation. This breakthrough follows a unanimous recommendation from the 16-member Cellular, Tissue, and Gene Therapies Advisory Committee of the US Food and Drug Administration (FDA).

Pioneering Treatment for RPE65-Mediated Inherited Retinal Disease

Luxturna is an adeno-associated viral (AAV) vector gene therapy designed to be administered once, aiming to restore vision in patients suffering from biallelic RPE65-mediated IRD—a condition that often progresses to complete blindness and for which there are currently no pharmacological treatments available. This gene therapy introduces a correct copy of the RPE65 gene directly into retinal cells, enabling them to produce the enzyme necessary for visual function, which is otherwise deficient in affected individuals.

The recommendation for FDA approval of Luxturna is based on the positive results from a phase 3 clinical trial. In this late-stage study, Spark Therapeutics demonstrated that Luxturna was effective in maintaining functional vision and enhancing visual functions in patients, with significant improvements observed just 30 days after administration. Remarkably, 93% of trial participants showed improved navigation abilities in low-light conditions—a critical measure of the therapy’s efficacy.

Expert Insights and Long-term Efficacy

Katherine High, Head of Research and Development at Spark Therapeutics, highlighted the sustained benefits of Luxturna, noting, “The clinical program for LUXTURNA includes patient data that show efficacy for up to four years on endpoints including bilateral multi-luminance mobility test (MLMT) score change and full-field light sensitivity threshold (FST) testing, with observation ongoing.”

Principal Investigator of the Luxturna phase 3 trial, Albert M. Maguire, expressed optimism about the therapy’s potential, stating, “There currently are no pharmacologic treatment options for people living with RPE65-mediated IRD, who in most cases progress to complete blindness. Today’s advisory committee vote is an important step closer to the day that discussion can include potentially treating the blindness caused by their IRD.”

Luxturna’s advancement to the brink of FDA approval marks a pivotal moment in the treatment of genetic disorders through gene therapy. By targeting the genetic root of RPE65-mediated IRD, Luxturna offers not just a treatment but a potential cure for patients who have had little hope until now. This development is poised to set a precedent for future therapies aimed at genetic conditions and underscores the increasing role of genetic engineering in medicine.