FDA grants rare pediatric disease designation to Duchenne muscular dystrophy drug

Key takeaways:

• AOC 1044 demonstrated increased exon 44 skipping compared with placebo in an ongoing phase 1/2 trial.
• Avidity plans to share further study data in the second half of 2024.

The FDA has granted rare pediatric disease designation to an investigational therapy for the treatment of Duchenne muscular dystrophy in those with mutations amenable to exon 44 skipping, according to the manufacturer.

According to a release from Avidity Biosciences, AOC 1044 is being assessed in EXPLORE44, a randomized, placebo-controlled, double-blind, phase 1/2 clinical trial in approximately 40 healthy volunteers and 24 individuals aged 7 to 27 years with Duchenne muscular dystrophy (DMD) mutations amenable to exon 44 skipping (DMD44). The ongoing study aims to evaluate the safety, tolerability, pharmacokinetics and pharmacodynamic effects of single and multiple ascending doses of AOC 1044 administered intravenously.

The FDA had previously granted fast track designation to AOC 1044 in April 2023, before granting orphan drug designation in August 2023. The therapeutic was also granted  orphan designation by the European Medicines Agency.

The rare pediatric disease designation was granted by the FDA based on positive data reported from EXPLORE44 in December 2023, in which the novel therapeutic was found to be well tolerated, demonstrated statistically significant exon 44 skipping compared with placebo of up to 1.5% in healthy volunteers after a single dose of 10 mg/kg, as well as increased exon skipping in all participants.

Avidity stated plans to provide a first look at AOC 1044 data during the second half of 2024.

“Currently, there are no therapies approved targeting exon 44, and FDA rare pediatric disease designation reinforces the potential of AOC 1044 in treatment of DMD in people living with mutations amenable to exon 44 skipping," Steve Hughes, MD, chief medical officer at Avidity Biosciences, told Healio in an email. "We recently announced healthy volunteer data from our phase 1/2 study, demonstrating AOC 1044 was well tolerated, with statistically significant exon 44 skipping compared to placebo of up to 1.5% after a single dose of 10 mg/kg, and increased exon skipping in all participants."