Submitted and Edited by Clark Pinyan, MD
Nusinersen in Type 1 Spinal Muscular Atrophy: Twelve-Month Real-World Data.
Pane M et al. Ann Neurol 2019;86:443-451.
Nusinersen is an antisense oligonucleotide therapy for spinal muscular atrophy (SMA), which targets the SMN2 pre-messenger RNA to increase production of SMN2. Although initially indicated for use in all ages, initial trials showed improvement was greater in younger patients with milder disease. This Italian study followed 85 patients 12 months from nusinersen therapy, with severity ranging from severe to mild, and age at treatment from 2 months to 15 years, 11 months. Although less than 15% of patients experienced some functional decline, over 60% improved at least 2 points on the CHOP INTEND scale, with continued improvements in the second six months. Gains were greatest for children under 24 months, but smaller gains still seen for older patients. No significant gains were noted in the most severe phenotypes. Caregiver questionnaires obtained from 72 families reported subjective overall stability (11) or increased function (61).
For a revolutionary therapy in a rare disease, it takes time to fairly assess the impact, as well as clearly define the population that would benefit. This article demonstrates some benefit for populations at an expanded age range, though magnitude and duration still remain to be seen.
Several of our members are already administering nusinersen in specialty clinics. We need clearer data to help set patient and family expectations and plan for future therapy.