Avidity Biosciences announces data from MARINA clinical trial of AOC 1001

Avidity Biosciences announced topline data from the Phase 1/2 MARINA clinical trial of AOC 1001 for the treatment of myotonic dystrophy type 1, or DM1, demonstrating functional improvement, DMPK reduction, splicing improvements and a favorable safety and tolerability profile. The AOC 1001 topline data were highlighted in an oral presentation at the 75th American Academy of Neurology, or AAN, annual meeting in Boston. AOC 1001, Avidity’s lead clinical program utilizing its AOC platform, is designed to address the root cause of DM1, an underrecognized, progressive and often fatal neuromuscular disease with no approved therapies. The Phase 1/2 MARINA trial is a randomized, double-blind, placebo-controlled study designed to evaluate the safety and tolerability of single and multiple ascending doses of AOC 1001 administered intravenously in adults with DM1. Topline data were assessed from a 3:1 randomized study with 38 participants, who were administered one dose of 1 mg/kg AOC 1001, three doses of either 2 mg/kg AOC 1001 or 4 mg/kg of AOC 1001, or placebo. AOC 1001 Phase 1/2 topline data demonstrated: Directional improvement in multiple functional assessments including measures of myotonia, strength and mobility: Myotonia was measured by video hand opening time and is a hallmark of DM1 where relaxation of key muscle groups is impaired. Measures of strength included the Quantitative Muscle Testing (QMT) total score which is based on six muscle groups from both the upper and lower body. Mobility was assessed by the 10-meter walk run test (10mWRT) and the Timed Up and Go test The endpoints used in MARINA measure important aspects of the disease and correspond to those utilized in the ongoing END-DM1 natural history study. Meaningful DMPK reduction and splicing changes in participants treated with AOC 1001. Splicing changes followed by directional improvements in functional measures at 2 mg/kg and 4mg/kg doses of AOC 1001. AOC 1001 demonstrated broad splicing improvements in more than a thousand genes impacted by DM1, confirming activity in the nucleus. Favorable safety and tolerability profile of AOC 1001 with most adverse events mild or moderate. Avidity continues to work with the U.S. Food and Drug Administration (FDA) regarding the partial clinical hold on new participant enrollment in the AOC 1001 program. The company continues to dose the participants at both 2 mg/kg and 4 mg/kg of AOC 1001 in the MARINA open-label extension (MARINA-OLE(TM)) study to evaluate the long-term safety and tolerability of AOC 1001 in participants with DM1 who were previously enrolled in the Phase 1/2 MARINA trial. Avidity remains on track to share a first look at the data from the MARINA-OLE study at the end of 2023.