Biogen Reports Positive Results for Pre-symptomatic Treatment with Spinraza in SMA

Rare Daily Staff

Treating infants with spinal muscular dystrophy with the antisense oligonucleotide Spinraza before they showed any symptoms attained did significantly better than patients captured in a natural history of the disease, according to data was published in Neuromuscular Disorders.

Spinal muscular dystrophy, or SMA, is a rare, genetic, neuromuscular disease that is characterized by a loss of motor neurons in the spinal cord and lower brain stem, resulting in severe, progressive muscle atrophy and weakness. Approximately one in 10,000 live births have a diagnosis of SMA, and it is a leading genetic cause of infant mortality.

Data from the NURTURE study showed that as of March 2019, all participants were alive, without the need for permanent ventilation and experienced continuous improvements with the majority achieving motor milestones in timelines consistent with normal development. The results also demonstrated durability of effect with children making progress throughout the study.

“This pioneering study has far surpassed what we thought was possible and redefined our expectations of how early treatment helps individuals with SMA achieve optimal outcomes,” said Darryl De Vivo, Professor of Neurology and Pediatrics at Columbia University Irving Medical Center in New York. “The extraordinary results achieved in this study underline the critical importance of newborn screening and early treatment of the clinically normal infants with SMA before the onset of any clinical symptoms.”

NURTURE is an ongoing, phase 2, open-label study of 25 infants with the genetic diagnosis of SMA (most likely to develop SMA Type 1 or 2) who received their first dose of Spinraza in the pre-symptomatic stage and before six weeks old. The study, conducted at 15 sites in seven countries, has results up to 45.4 months. When compared with the natural history of the disease, the results are dramatic in their impact on changing the course of SMA.

As of March 2019 all infants in the study were 25 months or older, past the typical age of symptom onset for SMA Type 1 and Type 2, and were alive without the need for permanent ventilation. In comparison to the natural history of SMA, many of these infants would likely have passed away or require permanent ventilation on average by 13.5 months.

Additionally, the majority of study participants achieved motor milestones in timeframes consistent with the World Health Organization (WHO) standards, with 100 percent sitting independently and 88 percent walking independently.

Spinraza is an antisense oligonucleotide that is approved to treat infants, children, and adults with SMA in more than 40 countries. It was developed using Ionis Pharmaceuticals’ proprietary technology that is designed to target a root cause of SMA by increasing the amount of full-length survival motor neuron (SMN) protein, which is critical to maintaining motor neurons.

Photo: Darryl De Vivo, Professor of Neurology and Pediatrics at Columbia University Irving Medical Center in New York