Avidity Biosciences has obtained orphan drug designation from the US Food and Drug Administration (FDA) for its AOC 1044 to treat Duchenne muscular dystrophy (DMD) in people with mutations amenable to exon 44 skipping (DMD44).

DMD is a rare, early-onset genetic condition that causes gradual muscle damage and weakness due to the loss of the dystrophin protein.

AOC 1044 provides phosphorodiamidate morpholino oligomers to skeletal muscles and cardiac tissue.

Its purpose is to selectively exclude exon 44 of the dystrophin gene, thereby facilitating the production of dystrophin.

The Phase 1/2 EXPLORE44 clinical trial is currently evaluating AOC 1044 as a treatment for individuals with DMD44. It marks the initial step in assessing a series of AOCs being developed by the company to address DMD.

Avidity intends to disclose findings from the EXPLORE44 trial's segment involving healthy volunteers in the fourth quarter of 2023. It is currently enrolling participants living with DMD44 in the trial.

In April 2023, the company secured fast-track designation from the FDA for AOC 1044 to treat DMD44.

Avidity chief medical officer Steve Hughes stated: “There are currently no treatment options that target the underlying cause of DMD44. AOC 1044 is designed to specifically skip exon 44 of the dystrophin gene to enable the production of functional dystrophin protein.

“We look forward to advancing AOC 1044 in clinical development and bringing this very important treatment to patients as quickly and safely as possible."