Jenna Lammers, MSR/PT, CNT, PCS a, b, c, Stephanie Salabarria, BHSc a, b, c, Carla D. Zingariello, DOc, e, Carmen Leon-Astudillo, MD a, c, d, Julie A. Berthy, ARNP, DNP a, b, c, Kara Godwin Wild, MSN, ARNP, PNP-BC a, b, c, Samantha Norman, MPH a, b, c, Jennifer Shifflet, PA-C a, b, c, Barry J. Byrne, MD, PhD a, b, c
a.Powell Gene Therapy Center, University of Florida, Gainesville FL
b.Child Health Research Institute, University of Florida, Gainesville FL
c.Department of Pediatrics, College of Medicine, University of Florida, Gainesville, FL ‘
d.Division of Pulmonary Medicine, University of Florida, Gainesville, FL
e.Division of Pediatric Neurology, University of Florida, Gainesville, FL
Background: Validated functional outcome measures used in clinical trials for Spinal Muscular Atrophy (SMA) have reliably followed disease natural history models, captured change post- intervention, and have been instrumental in the FDA approval of three life-saving treatments. In 2020 a new validated lifespan outcome, the Neuromuscular Gross Motor Outcome (GRO) emerged as a reliable measure to detect changes in motor function across all ages and types of treated SMA. As newborn screening went live in Florida in 2020, our clinical research team hypothesized that the GRO may be a clinically relevant tool to monitor change in this newborn screen identified- early treated (NBSI-ET) population.
Methods: Prospective birth cohort study with 10 NBSI-ET infants receiving care at the Center for Neuromuscular and Rare Diseases at the University of Florida. Children completed simultaneous functional testing on the Test of Infant Motor Performance (TIMP), Children’s Hospital of Philadelphia Test of Neuromuscular Disorders (CHOP-Intend), and GRO by a single reliability-trained clinical evaluator over a two-year period.
Results: All subjects achieved their lowest GRO score at birth and demonstrated steady improvement over two years without aging out or reaching functional or full ceilings.
Conclusion: The Neuromuscular GRO effectively monitored motor function changes in this NBSI-ET SMA cohort, overcoming the age and ability limitations of the TIMP and CHOP-Intend.