An Antibody–Oligonucleotide Conjugate for Myotonic Dystrophy Type 1

mRNA.

In this phase 1-2, multicenter, double-blind, randomized, placebo-controlled trial, we assigned participants with myotonic dystrophy type 1 to receive del-desiran intravenously in a single dose (1 mg per kilogram of body weight) or three doses (2 mg or 4 mg per kilogram) or placebo. The primary end point was safety, and secondary end points were the pharmacokinetic and pharmacodynamic profiles of del-desiran and changes in downstream aberrant splicing patterns at 43 days in the 1-mg group and at 92 days (49 days after the second dose) in the 2-mg and 4-mg groups.