#United States #San Diego #Avidity Biosciences #delpacibart #FSHD

Avidity Biosciences Makes Significant Progress in FSHD Treatment

Avidity Biosciences, a biopharmaceutical company noted for developing innovative RNA therapeutics, recently announced a key milestone: the completion of participant enrollment in their biomarker cohort of the Phase 1/2 FORTITUDE™ clinical trial. This trial focuses on delpacibart braxlosiran (del-brax), the world's first investigational therapy aimed at treating Facioscapulohumeral Muscular Dystrophy (FSHD), a rare and debilitating neuromuscular disorder.

FSHD affects an estimated 45,000 to 87,000 individuals within the United States and the European Union, causing progressive muscle weakness and significant physical limitations. Given that there are currently no approved treatments available, the completion of enrollment in the FORTITUDE trial signifies an important step towards meeting a critical medical need.

Dr. Steve Hughes, Chief Medical Officer at Avidity, noted the importance of this milestone, emphasizing the company's commitment to potentially accelerating the drug's approval in the U.S. for FSHD patients. With a total of 51 participants enrolled, the focus now shifts to analyzing the impressive data already obtained with a dosage of 2 mg/kg of del-brax. Initial results have shown unprecedented reductions in DUX4-regulated genes, significant decreases in biomarkers, and positive trends in functional improvements, all while maintaining a favorable safety profile.

Avidity's trials will help inform the design of a potential global Phase 3 study, with initiation expected in the following quarter. In addition, they plan to present topline data from ongoing dose escalation cohorts. The company’s research efforts aim to not only provide novel therapeutic options for FSHD but also potentially deliver the first-ever globally approved drug designed to target the disease.

Understanding Del-brax and the FORTITUDE Trial

Del-brax represents a pioneering approach to treating FSHD by targeting the mRNA transcript of the disease-causing gene DUX4. The abnormal expression of DUX4 leads to the activation of detrimental genes in muscle cells, resulting in muscle weakness and progressive disability. By reducing DUX4 mRNA and protein expression, del-brax aims to halt the progression of this degenerative disease.

The ongoing FORTITUDE trial is a randomized, double-blind clinical investigation enrolling 90 individuals diagnosed with FSHD. This study examines multiple doses to evaluate del-brax's pharmacokinetics, safety, and efficacy. Although it is designed to assess therapeutic activity through various biomarkers, it is not statistically powered to measure functional benefits directly. Avidity's innovative methodologies for assessing muscle health categorize improvements across several measures including mobility and muscle strength.

The trial encompasses three different dose cohorts, with careful assessments of the safety and potential dosage regimens intended for future studies. Guidance from early data has allowed Avidity to pinpoint the optimal del-brax administration as 2 mg/kg every six weeks, so the next phases of the study can proceed with a clear blueprint in mind.

Moreover, participants finishing the FORTITUDE trial will have the opportunity to join an open-label extension study, further exploring the long-term safety and tolerability of del-brax.

The Promise of Avidity Biosciences

Avidity's mission is nothing short of transformative, striving to considerably improve the lives of individuals affected by rare and life-altering diseases through their Antibody Oligonucleotide Conjugates (AOCs™). Their recent progress in the FORTITUDE trial highlights their pioneering contributions in RNA therapeutic development.

As they navigate through regulatory pathways and prepare for upcoming data presentations, Avidity is positioned on the brink of substantial advancements in the treatment of neuromuscular diseases. The continued collaboration of scientific innovation, patient involvement, and rigorous clinical evaluation will hopefully usher in a new era of therapeutic options for those living with FSHD and similar disorders. Avidity’s work exemplifies a promising direction for not only targeted treatments but also for a broader patient community longing for effective therapies in the face of rare diseases.

For more detailed information surrounding the FORTITUDE trial, please visit clinicaltrials.gov and search for NCT05747924.