shares of avidity biosciences inc rna soared 39 in premarket trading on wednesday after the company said its experimental rna therapy when injected into the muscle has potential as a treatment for myotonic dystrophy type 1 a sometimes fatal neuromuscular disease the phase 12 clinical trial is the first time that rna has been delivered into the muscle in humans avidity said we are highly encouraged by 1001s early clinical profile and see positive readthrough to rnas antibody oligonucleotide conjugates platform broadly svb securities analyst joseph schwartz told investors on wednesday aviditys stock has declined 538 since the start of the year while the broader sp 500 spx is down 156