DUBLIN – Shares in PTC Therapeutics Inc. dropped as much as 13% during premarket trading Feb. 6 on eagerly awaited 12-month data for its oral spinal muscular atrophy (SMA) drug risdiplam, which is licensed to Genentech. Although patients with type 2 or type 3 SMA demonstrated statistically significant improvements in motor function, the level of that improvement evidently disappointed some investors.
Roche Holding AG and PTC Therapeutics Inc. together with their partner, the SMA Foundation, reported success in part two of the pivotal Sunfish study testing their survival motor neuron-2 splicing modifier risdiplam in patients with type 2 or 3 spinal muscular atrophy (SMA).
