Background: Recent investigations in treatment of Spinal Muscular Atrophy have focused upon children, who comprise the bulk of patients in clinical practice. The extent to which the identified dramatic benefits are related solely to young age with associated potential gains attributable to further development is unknown. An associated unknown is the extent to which treatments targeted to increasing SMN expression will translate to benefit amongst adults with SMA.
Objective: To determine the clinical changes noted in an adult cohort with SMA receiving Spinraza intrathecally.
Design/Methods: Adults with SMA were prospectively studied prior to and after initiation of Spinraza at a single center. Baseline and post treatment motor function was assessed using HFMSE, RULM, modified 9-hole peg, 6MWT, TUG, and quality of life measure, SF-36.
Results: Pre-dose functional testing started in July 2017, and post-testing occurred after injection at 6 months (mo.), 12 mo., and 18 mo. Currently, 15 patients (9 women, 6 men, mean age 36 ±14; range, 18-69) have performed pre-testing, 14 at 6 mo., 11 at 12 mo and 4 at 18 mo post-testing. 4 patients were type II and 11 were type III. Currently, 5 are ambulatory and 10 are non-ambulatory. HFMSE increased by >3 points and RULM maintained without clinically significant decline at 6, 12 and 18 mo. 6MWT average distance at pre-testing was 352 meters (n=5), and showed no clinically meaningful change (+/-) overtime. Modified 9-hole peg showed increased speed when performed dominant right hand at 6, 12 and 18 mo. SF-36 scores improved from pre-testing at 6 and 12 mo. Anecdotally, patients report decreased fatigue, and increased activity levels throughout the day.
Conclusions: Improvement and maintenance of functional status was observed in all 15 adults with SMA, types II and III, receiving treatment with Spinraza. Continued monitoring of functional as well as self-reported outcome measures is necessary to identify longer term benefit of treatment in the adult population.