Based on the activation of this toxic pathway in DM1 patients, AMO Pharma performed a Phase IIb clinical trial targeting GSK3β and, respectively, the toxic GSK3β-cyclin D3-CUGBP1 pathway in adult patients with congenital and childhood-onset DM1 [24] (Table 1). Here, CCND3 is linked to myotonic dystrophy type 1.