Announcement • Feb 28
Avidity Biosciences, Inc.(NasdaqGM:RNAM) dropped from NASDAQ Biotechnology Index Avidity Biosciences, Inc. has been removed from NASDAQ Biotechnology Index . Announcement • Feb 20
Avidity Biosciences, Inc. Announces Final Results from the Completed Phase 1/2 Marine Trial of Delpacibart Etedesiran (Del-Desiran) for Treatment of Myotonic Dystrophy Type 1 Avidity Biosciences, Inc. announced that the final results from the completed Phase 1/2 MARINA® trial of delpacibart etedesiran (del-desiran) in people living with myotonic dystrophy type 1 (DM1) will be published in the February 19 issue of The New England Journal of Medicine (NEJM). The manuscript is titled ‘An Antibody Oligonucleotide Conjugate for Myotonic Dystrophy Type 1.’DM1 is an underrecognized, progressive and often fatal neuromuscular disease with no disease modifying therapies. Del-desiran is an investigational treatment designed to address the underlying genetic root cause of DM1 by reducing total levels of the toxic, DMPK (myotonic dystrophy protein kinase) mRNA. The accumulation of these toxic mRNA sequester key RNA-regulatory proteins that subsequently lead to missplicing of several downstream genes, resulting in the diverse clinical manifestations of disease. The Phase 1/2 MARINA trial was a randomized, double-blind, placebo-controlled study designed to evaluate the safety and tolerability of single and multiple ascending doses of del-desiran administered intravenously in adults with DM1 for six months. Data were assessed from 38 participants who were randomized 3:1 to receive one dose of 1 mg/kg del-desiran, three doses of either 2 mg/kg del-desiran or 4 mg/kg del-desiran (reflected as siRNA dose), or placebo. The primary endpoint of the study was to evaluate the safety and tolerability of del-desiran. Exploratory endpoints were to evaluate the clinical activity of del-desiran across multiple efficacy measures. Results from the Phase 1/2 MARINA study of del-desiran published in NEJM demonstrated: Effective delivery of del-desiran (siRNA) to muscle, with a mean ~ 40% reduction in DMPK mRNA across all treated participants. Splicing improvements in a key set of muscle-specific genes following treatment with del-desiran 2 mg/kg and 4 mg/kg. Improvements in exploratory functional measures including: Hand function/myotonia (video hand opening time, or vHOT); Muscle strength (Quantitative Muscle Testing, or QMT total score); Mobility (10-Meter Walk/Run Test, or 10mWRT, and Timed Up and Go test, or TUG); DM1-Activ, a patient-reported outcome that measures activities of daily living (e.g., taking a shower, visiting family or friends, and walking up stairs). Acceptable safety and tolerability with most treatment emergent adverse events (TEAEs) mild or moderate in participants with DM1 and did not result in discontinuation. Two severe, serious AEs occurred in two participants in the 2 mg/kg and 4 mg/kg dose cohorts, with one participant discontinuing the study in the 4 mg/kg cohort. One of these SAEs was deemed drug-related. Del-desiran (4 mg/kg) is currently being assessed in the global Phase 3 HARBOR™ study in people living with DM1 who are age 16 and older and in the ongoing HARBOR open-label extension (HARBOR-OLE™) trial with all the participants who completed the Phase 1/2 MARINA trial. The global Phase 3 HARBOR study completed enrollment in July 2025 and a 54-week topline data readout is expected in the second half of 2026. Announcement • Nov 19
Avidity Biosciences, Inc. Announces U.S. Managed Access Program for Investigational Therapy Del-Zota in DMD44 Avidity Biosciences, Inc. announced its Managed Access Program (MAP) for investigational therapy delpacibart zotadirsen (del-zota) for eligible people with Duchenne muscular dystrophy mutations amenable to exon 44 skipping (DMD44) in the United States. Under an FDA-authorized treatment protocol, Avidity will provide del-zota to eligible boys and men with DMD44 through participating healthcare providers. Enrollment is anticipated to begin by year end, and participants in EXPLORE44-OLE will have the option to transition to the MAP as they complete 2 years of treatment. Avidity aligned with FDA on a path forward for a BLA submission for del-zota following an October 2025 pre-BLA meeting, with the submission planned for 2026 for accelerated approval. Participants will transition to commercial drug supply upon future potential FDA approval and product availability. One participant discontinued from EXPLORE44-Ole following an event of hypersensitivity. Del-zota has received Rare Pediatric Disease, Orphan Drug, Fast Track and Breakthrough Therapy designations by the U.S. Food and Drug Administration (FDA) and Orphan designation by the European Medicines Agency (EMA). 
