Dr. Crystal Proud, Pediatric Neurologist at Children’s Hospital of the King’s Daughters, remarked, “Our evolving understanding of gene therapy indicates there may be an opportunity for better outcomes. Improvements in motor function together with decreases in neurofilament levels seen after treatment with SPINRAZA in RESPOND show that we may be able to further maximize benefits for patients.”

Key highlights from the NfL data presented include:

• Among participants with 2 SMN2 copies, all exhibited elevated baseline NfL levels relative to healthy children of similar age. Notably, infants under 9 months experienced a mean decrease of 70% from baseline, while children over 9 months saw a mean decrease of 78%.
• Participants with 3 SMN2 copies demonstrated varied responses, with baseline NfL levels elevated in some cases. Notable reductions were observed in those with elevated levels at baseline, while stability was maintained in others.

Dr. Priya Singhal, Head of Development and interim Chief Medical Officer at Biogen, emphasized, “Biogen is committed to advancing biomarkers to accelerate drug development for neurodegenerative diseases like SMA and ALS. The RESPOND findings underscore the value of neurofilament as an objective marker for assessing remaining unmet needs in SMA patients who have previously received gene therapy.”

Previously reported RESPOND efficacy results highlighted improvements in motor function among most participants, with no new safety concerns identified. Serious adverse events were reported in 34% of participants, with none considered related to SPINRAZA or leading to study withdrawal.

Further data from the RESPOND study will be presented at upcoming conferences, including the 4th International Congress on Spinal Muscular Atrophy hosted by SMA Europe.