-- FDA alignment on accelerated and full approval pathways for delpacibart braxlosiran (del-brax) in facioscapulohumeral muscular dystrophy (FSHD) ---- Jeffrey M. Statland, M.D., Professor of Neurology, University of Kansas Medical Center, and FORTITUDE trial investigator, will present topline del-brax data from dose escalation cohorts in oral presentation ---- Stephen Tapscott, M.D., Ph.D., Professor of Human Biology and Clinical Research, Fred Hutchinson Cancer Center, will highlight results on the charac ...

Core Insights - Avidity Biosciences announced positive topline data from the Phase 1/2 FORTITUDE™ program for delpacibart braxlosiran (del-brax) in treating Facioscapulohumeral Muscular Dystrophy (FSHD), showing improvements in function, strength, and patient-reported outcomes compared to placebo [1][3][6] - The company plans to submit a Biologics License Application (BLA) for accelerated approval in the second half of 2026 [1][3] - Del-brax is the first investigational therapy targeting the underlying cause of FSHD by directly addressing the DUX4 gene, with no approved therapies currently available for this condition [2][13] Group 1: Clinical Data and Results - The FORTITUDE™ trial included a randomized, placebo-controlled, double-blind study evaluating 39 participants on doses of 2 mg/kg or 4 mg/kg of del-brax over 12 months [5][10] - Results indicated consistent improvements in functional mobility and muscle strength, as measured by the 10-Meter Walk-Run test, Timed Up and Go, and quantitative muscle testing [6][9] - Significant reductions in biomarkers such as KHDC1L and creatine kinase were observed, indicating muscle damage [6][7] Group 2: Safety and Regulatory Pathway - Del-brax demonstrated favorable long-term safety and tolerability, with most adverse events being mild or moderate, and no serious adverse events reported [7][9] - The U.S. FDA has opened the accelerated approval regulatory pathway for del-brax, and a global Phase 3 FORWARD™ study has been initiated [3][4] Group 3: Future Developments - The ongoing biomarker cohort of the FORTITUDE trial aims to assess the impact of del-brax on KHDC1L levels, with topline data expected in Q2 2026 [7][11] - Avidity is advancing its clinical development pipeline, focusing on RNA therapeutics through its proprietary Antibody Oligonucleotide Conjugates (AOCs™) platform [16]

Core Insights - Avidity Biosciences has completed enrollment in the FORTITUDE biomarker cohort for delpacibart braxlosiran (del-brax), targeting accelerated approval for treating facioscapulohumeral muscular dystrophy (FSHD) [1][2] - The company plans to present topline data from the FORTITUDE trial in Q2 2025, with regulatory alignment anticipated for a global Phase 3 trial [1][6] - Del-brax aims to be the first approved therapy for FSHD, a rare disease affecting approximately 45,000 to 87,000 individuals in the U.S. and EU [2][10] Company Overview - Avidity Biosciences focuses on RNA therapeutics, specifically Antibody Oligonucleotide Conjugates (AOCs™), to address rare neuromuscular diseases [11] - The company is advancing clinical programs for multiple conditions, including myotonic dystrophy type 1 and Duchenne muscular dystrophy, alongside FSHD [11] Clinical Trial Details - The FORTITUDE trial is a Phase 1/2 randomized, placebo-controlled study evaluating del-brax in 90 participants with FSHD [3] - The trial assesses safety, tolerability, pharmacokinetics, and pharmacodynamics, using biomarkers like DUX4-regulated genes and MRI measures [3][4] - The ongoing biomarker cohort evaluates del-brax at a dose of 2 mg/kg every six weeks for 12 months, focusing on changes in DUX4-regulated gene expression [5] Efficacy and Safety Data - Initial data from the 2 mg/kg dose of del-brax show over 50% reductions in DUX4-regulated genes, alongside trends of functional improvement and favorable safety [2][9] - The trial's design includes three dose cohorts, with the 2 mg/kg every six weeks identified for future studies [4] Future Plans - Avidity aims to share additional data and key milestones from the del-brax program in Q2 2025, including regulatory updates and topline results [2][6]