Shares of Avidity Biosciences Inc. (NASDAQ:RNA) dropped 15% March 30 as the company disclosed details of the serious adverse event (SAE) that prompted a partial clinical hold in September 2023 on the phase I/II trial testing AOC-1001 in adults with myotonic dystrophy type 1 (DM1).

A preliminary assessment of Avidity Biosciences Inc.’s phase I/II study of AOC-1001 in myotonic dystrophy type 1 (DM1) showed the first-ever targeted delivery of RNA into muscle, an area previously untreatable with existing RNA therapeutics. Sarah Boyce, Avidity’s CEO, said in a Dec. 14 call that the antibody oligonucleotide conjugate’s data were unprecedented in the RNA space and in myotonic dystrophy type 1 (DM1), labeling it a “revolutionary advancement.”

Arthex Biotech SA has achieved key regulatory milestones in its program to develop ATX-01 in myotonic dystrophy type 1 (DM1). Having held a pre-IND meeting with the FDA last year and received scientific advice from the EMA, Arthex plans to file an IND application in the U.S. and a clinical trial application (CTA) in Europe next year.

Pepgen Inc. has announced new preclinical data supporting the progression into clinical trials of PGN-EDODM1, its product candidate in development for the treatment of myotonic dystrophy type 1 (DM1).