Avidity Biosciences' Del-zota Demonstrated Reversal of Disease Progression Across Key Functional Endpoints in EXPLORE44® and EXPLORE44-OLE™ Phase 1/2 Trial in People Living with DMD44

Core Insights - Avidity Biosciences announced positive data from the EXPLORE44 and EXPLORE44-OLE trials, showing unprecedented improvements in multiple functional measures for Duchenne muscular dystrophy (DMD) patients treated with del-zota [1][3][4] - The company is on track to submit a Biologics License Application (BLA) to the FDA by the end of 2025 for accelerated approval of del-zota [1][6] Clinical Trial Results - Participants treated with del-zota showed a 25% increase in normal dystrophin production and a reduction of creatine kinase (CK) levels by over 80% compared to baseline, maintained near normal levels for up to 16 months [3][4] - Functional improvements included: - 4-Stair Climb (4SC): Improved by 2.1 seconds compared to a decline of 2.7 seconds in the natural history group [4] - 10-Meter Walk/Run Test (10mWRT): Improved by 0.7 seconds compared to a decline of 1.5 seconds in the natural history group [4] - Time to Rise from Floor (TTR): Improved by 3.2 seconds compared to a decline of 1.6 seconds in the natural history group [4] - Performance of Upper Limb (PUL): Improved by 1.5 points compared to a decline of 0.7 points in the natural history group [12] Safety Profile - Del-zota demonstrated a favorable long-term safety and tolerability profile, with most treatment-emergent adverse events being mild or moderate [5] - Common adverse events included upper respiratory tract symptoms, diarrhea, falls, back pain, and headaches [5] Future Plans - Avidity is preparing for a confirmatory study to support full global approval of del-zota [6] - The company plans to present additional data from the EXPLORE44 program at upcoming scientific congresses [1]