Novartis said its Phase III HARBOR study of del-desiran in myotonic dystrophy type 1 (DM1) failed to meet the primary endpoint; video hand-opening time (vHOT) showed no statistically significant improvement versus placebo. The company reported signals of clinical activity in secondary and exploratory analyses and said safety was overall consistent with prior data. Novartis will analyze the full dataset and consult regulators to determine next steps.

2026-09-08

Novartis said its Phase III HARBOR study of del-desiran in myotonic dystrophy type 1 (DM1) failed to meet the primary endpoint; video hand-opening time (vHOT) showed no statistically significant improvement versus placebo. The company reported signals of clinical activity in secondary and exploratory analyses and said safety was overall consistent with prior data. Novartis will analyze the full dataset and consult regulators to determine next steps.