Biogen announces topline results from Phase 1 study of salanersen

Biogen (BIIB) announced topline results from the Phase 1 study of salanersen, an antisense oligonucleotide, ASO, being developed for the treatment of spinal muscular atrophy, SMA. Leveraging the same mechanism of action as SPINRAZA but designed to achieve greater potency, salanersen has the potential to achieve high efficacy and enable once yearly dosing. An interim analysis of the Phase 1 study in participants with SMA who were previously treated with gene therapy was conducted to inform the decision on whether to move salanersen forward into registrational studies. Both dose levels tested, 40 mg and 80 mg, given once a year, were generally well-tolerated and led to substantial slowing of neurodegeneration, as shown by reductions in neurofilament. Exploratory clinical outcome data shows clinically meaningful improvements in function and attainment of new World Health Organization, WHO, milestones over 1 year. These data will be presented today at the SMA Research & Clinical Care Meeting hosted by Cure SMA in Anaheim, Calif.