FDA Puts Investigational DM1 Therapy AOC 1001 on Fast Track
The U.S. Food and Drug Administration (FDA) has granted fast track designation to AOC 1001, an investigational treatment for myotonic dystrophy type 1, known as DM1, a late-developing muscle disorder.
The designation will enable AOC 1001’s developer, Avidity Biosciences, to have more frequent interactions with the FDA throughout the development process. The overall goal of the FDA’s fast track program is to expedite the review of therapies that have the potential to improve care for serious conditions.
“DM1 is an underrecognized, progressive and often fatal disease with no therapeutic options,” Sarah Boyce, president and CEO of Avidity, said in a press release.
“Fast Track designation for AOC 1001 underscores this unmet need and allows us to expeditiously work with FDA to potentially deliver this first-in-class therapy to people living with DM1 as quickly as possible,” Boyce said.
Mutations in the gene DMPK cause DM1, which usually presents itself in adults in their 20s and 30s.
Specifically, when cells “read” the mutated DMPK gene, they produce an abnormally long messenger RNA (mRNA) — the intermediary molecule made when a cell “reads” a gene to make a protein. This abnormally long mRNA is what ultimately drives disease progression, forming atypical clumps that are toxic to cells.
AOC 1001 was designed to reduce the levels of this toxic DMPK mRNA in cells.
The therapy contains a short interfering RNA (siRNA) — a specialized kind of RNA molecule that can bind to mRNA and target it for destruction — that is attached to an antibody that helps the siRNA to get inside of muscle cells.
Preclinical experiments in cell models and in non-human primates have shown that the medicine can reduce the levels of toxic DMPK mRNA. Preclinical studies also suggested that AOC 1001 has a generally good safety profile, according to Avidity.
Earlier this year, the FDA cleared Avidity to start clinical testing of AOC 1001. The company is planning a Phase 1/2 clinical trial called MARINA (NCT05027269), which is expected to enroll 44 adults with DM1, who will randomly be given either AOC 1001 or a placebo over the course of the study.
The main goal of MARINA is to assess the treatment’s safety and tolerability. AOC 1001’s activity also will be assessed through specific biomarkers, such as the levels of DMPK mRNA. The study is not designed to assess functional benefit, though measures of muscle strength, mobility, and patient-reported quality of life will be assessed.
In both the U.S. and the EU, AOC 1001 has been designated an orphan drug, recognizing its potential to treat a rare, life-threatening diseases.