FDA grants fast track designation for facioscapulohumeral muscular dystrophy treatment

The FDA has granted fast track designation to Avidity Biosciences Inc. for its novel RNA therapeutic AOC 1020, an antibody oligonucleotide conjugate being studied for the treatment of facioscapulohumeral muscular dystrophy.

According to a release from Avidity, AOC 1020 combines a proprietary monoclonal antibody with a muscle-targeting small interfering RNA designed to reduce expression of double homeobox 4 (DUX4) mRNA. In those with facioscapulohumeral muscular dystrophy (FSHD), abnormal expression of the DUX4 protein results in alterations in muscle cell gene expression which may lead to steady loss of muscle function.

AOC 1020 is currently being evaluated in the phase 1/2 FORTITUDE clinical trial, a randomized, placebo-controlled, double-blind study that has enrolled approximately 70 adults diagnosed with FSHD. The study will examine the safety, tolerability and pharmacokinetics of IV administration of the drug. Currently, there are no FDA-approved treatments for those living with the disease, the company stated.

“The FDA fast track designation for AOC 1020 reinforces the importance of finding an effective treatment to help people living with FSHD, a devastating and debilitating muscular dystrophy disorder with no treatment options,” Steve Hughes, MD, chief medical officer at Avidity, stated in the release. “AOC 1020 is designed to directly target the disease-causing gene, DUX4, to address the underlying cause of FSHD.”

Avidity additionally stated in the release that it intends to share results from an early assessment of AOC 1020 in approximately half of study participants from the FORTITUDE trial in the first half of 2024.