Avidity Biosciences Announces Completion of Enrollment for HARBOR™, the First Global Phase 3 Trial of Delpacibart Etedesiran (del-desiran) for Treatment of DM1 and Provides Guidance on Regulatory Submission
Avidity Biosciences (NASDAQ:RNA) has completed enrollment for HARBOR™, the first global Phase 3 trial of delpacibart etedesiran (del-desiran) for treating myotonic dystrophy type 1 (DM1). The company expects topline data in Q2 2026 and plans to submit marketing applications in the U.S., EU, and Japan starting in H2 2026.
Del-desiran, designed to address DM1's underlying genetic cause, has received multiple regulatory designations including Breakthrough Therapy, Orphan Drug, and Fast Track from the FDA. The HARBOR trial involves approximately 150 patients across 40 global sites, evaluating the drug's efficacy through various endpoints including video hand opening time (vHOT) and muscle strength measurements.
Avidity Biosciences (NASDAQ:RNA) ha completato il reclutamento per HARBOR™, il primo studio globale di Fase 3 su delpacibart etedesiran (del-desiran) per il trattamento della distrofia miotonica di tipo 1 (DM1). L'azienda prevede di ottenere i dati principali nel secondo trimestre del 2026 e intende presentare le domande di autorizzazione al commercio negli Stati Uniti, nell'UE e in Giappone a partire dalla seconda metà del 2026.
Del-desiran, progettato per agire sulla causa genetica alla base della DM1, ha ricevuto diverse designazioni regolatorie tra cui Breakthrough Therapy, Orphan Drug e Fast Track dalla FDA. Lo studio HARBOR coinvolge circa 150 pazienti in 40 sedi a livello globale, valutando l'efficacia del farmaco attraverso vari parametri, tra cui il tempo di apertura della mano video (vHOT) e le misurazioni della forza muscolare.
Avidity Biosciences (NASDAQ:RNA) ha completado la inscripción para HARBOR™, el primer ensayo global de Fase 3 de delpacibart etedesiran (del-desiran) para el tratamiento de la distrofia miotónica tipo 1 (DM1). La compañía espera obtener datos principales en el segundo trimestre de 2026 y planea presentar solicitudes de comercialización en EE. UU., UE y Japón a partir del segundo semestre de 2026.
Del-desiran, diseñado para abordar la causa genética subyacente de la DM1, ha recibido múltiples designaciones regulatorias, incluyendo Breakthrough Therapy, Orphan Drug y Fast Track por parte de la FDA. El ensayo HARBOR involucra a aproximadamente 150 pacientes en 40 sitios globales, evaluando la eficacia del medicamento mediante varios puntos finales, incluyendo el tiempo de apertura de mano en video (vHOT) y mediciones de la fuerza muscular.
Avidity Biosciences (NASDAQ:RNA)가 근이영양증 1형(DM1) 치료를 위한 delpacibart etedesiran (del-desiran)의 최초 글로벌 3상 시험인 HARBOR™의 환자 등록을 완료했습니다. 회사는 2026년 2분기 주요 데이터를 기대하며 2026년 하반기부터 미국, 유럽연합, 일본에서 마케팅 신청을 계획하고 있습니다.
del-desiran은 DM1의 근본적인 유전적 원인을 겨냥해 설계되었으며, FDA로부터 Breakthrough Therapy, Orphan Drug, Fast Track 등 여러 규제 지정도 받았습니다. HARBOR 시험은 전 세계 40개 사이트에서 약 150명의 환자를 대상으로 하며, 비디오 손 열림 시간(vHOT)과 근력 측정 등 다양한 평가 지표를 통해 약물의 효능을 평가합니다.
Avidity Biosciences (NASDAQ:RNA) a terminé le recrutement pour HARBOR™, le premier essai mondial de phase 3 de delpacibart etedesiran (del-desiran) pour le traitement de la dystrophie myotonique de type 1 (DM1). La société prévoit de disposer des données principales au deuxième trimestre 2026 et envisage de déposer des demandes d'autorisation de mise sur le marché aux États-Unis, dans l'UE et au Japon à partir du second semestre 2026.
Del-desiran, conçu pour cibler la cause génétique sous-jacente de la DM1, a reçu plusieurs désignations réglementaires, notamment Breakthrough Therapy, Orphan Drug et Fast Track de la FDA. L'essai HARBOR implique environ 150 patients répartis sur 40 sites mondiaux, évaluant l'efficacité du médicament à travers divers critères, dont le temps d'ouverture de la main en vidéo (vHOT) et les mesures de la force musculaire.
Avidity Biosciences (NASDAQ:RNA) hat die Einschreibung für HARBOR™, die erste globale Phase-3-Studie von delpacibart etedesiran (del-desiran) zur Behandlung der Myotonischen Dystrophie Typ 1 (DM1), abgeschlossen. Das Unternehmen erwartet Erstdaten im zweiten Quartal 2026 und plant, ab der zweiten Hälfte 2026 Zulassungsanträge in den USA, der EU und Japan einzureichen.
Del-desiran, entwickelt zur Behandlung der zugrunde liegenden genetischen Ursache von DM1, erhielt mehrere regulatorische Designationen, darunter Breakthrough Therapy, Orphan Drug und Fast Track von der FDA. Die HARBOR-Studie umfasst etwa 150 Patienten an 40 Standorten weltweit und bewertet die Wirksamkeit des Medikaments anhand verschiedener Endpunkte, darunter die Video-Handöffnungszeit (vHOT) und Muskelkraftmessungen.
- First potential globally approved drug for DM1, addressing an unmet medical need
- Multiple regulatory designations secured (Breakthrough Therapy, Orphan Drug, Fast Track)
- Strong clinical data showing durable improvements in multiple endpoints
- Global regulatory alignment achieved prior to Phase 3 trial initiation
- Long timeline to potential approval with marketing applications not starting until H2 2026
- Results from Phase 3 HARBOR trial still pending until Q2 2026
Insights
Avidity's Phase 3 DM1 trial reaches full enrollment with potential for first-ever approved therapy by 2027.
Avidity Biosciences has achieved a critical milestone by completing enrollment in their HARBOR Phase 3 trial for delpacibart etedesiran (del-desiran) in myotonic dystrophy type 1 (DM1). This represents the first global Phase 3 trial for this rare neuromuscular disease which currently has no approved treatments. The significance cannot be overstated—this positions del-desiran to potentially become the first approved therapy worldwide for DM1 patients.
The company has established a clear regulatory timeline with topline data expected in Q2 2026 followed by marketing application submissions in multiple regions (US, EU, Japan) starting in H2 2026. Prior regulatory groundwork is evident through their receipt of Breakthrough Therapy, Orphan Drug, and Fast Track designations from the FDA, plus Orphan designations in Europe and Japan.
The study design demonstrates scientific rigor with approximately 150 patients randomized 1:1 to receive either del-desiran or placebo every eight weeks. The primary endpoint focuses on video hand opening time (vHOT), directly measuring myotonia—a hallmark symptom of DM1. Secondary endpoints comprehensively assess muscle strength and activities of daily living, providing a holistic evaluation of treatment benefit.
Most promising are references to existing clinical data showing "durable improvements in multiple clinical endpoints" compared to natural history data and evidence that del-desiran addresses the underlying genetic cause of disease progression. The company's Antibody Oligonucleotide Conjugate (AOC) platform represents an innovative approach to RNA therapeutics, with del-desiran serving as a potential validation of this novel technology.
-- Topline data readout from HARBOR study anticipated in Q2 2026 --
-- Marketing application submissions for del-desiran including in
anticipated to start in H2 2026; on track to potentially be the first globally approved drug for DM1--
-- On track to share updates from ongoing MARINA-OLE™ trial of del-desiran including long-term 4 mg/kg efficacy and safety data in Q4 2025 --
Prior to initiation of the HARBOR trial, Avidity aligned with global regulators, including FDA, on the registrational path for del-desiran. The Company plans to submit marketing applications beginning in the second half of 2026 including in
"Completing enrollment in our Phase 3 HARBOR study for del-desiran marks a significant step toward bringing the first potentially approved drug for DM1 to people around the world who are living with this devastating rare neuromuscular disease," said Steve Hughes, M.D., chief medical officer at Avidity. "The growing body of data from clinical studies to date support the promise of del-desiran, including durable improvements in multiple clinical endpoints compared to natural history data and evidence that del-desiran is addressing the underlying genetic cause of disease progression. These encouraging results suggest that this potential therapy may be transformational for patients who urgently need treatment options. We extend our deepest appreciation to the DM1 community for their ongoing support of our research and development program, especially the patients, families, global advocacy groups, healthcare providers and staff who are part of the HARBOR and MARINA-OLE™ studies."
Del-desiran is an investigational treatment designed to address the underlying genetic cause of DM1, a rare, hereditary, progressive neuromuscular disease that shortens life expectancy and requires life-long care. DM1 is characterized by multisystemic manifestations including myotonia and progressive muscle weakening and may be underrecognized because it presents heterogeneously across skeletal, cardiac, and smooth muscles, leading to impairment of the cardiovascular, gastrointestinal, respiratory, ocular, and/or endocrine systems. Currently, there are no approved drugs for people living with DM1.
Del-desiran has received Breakthrough Therapy, Orphan Drug and Fast Track designations by the
About the Phase 3 HARBOR™ Trial
The global Phase 3 HARBOR™ trial is a randomized, placebo-controlled, double blind pivotal study designed to evaluate del-desiran in approximately 150 people (age 16 and older) living with DM1. The trial is being conducted at approximately 40 sites globally. Patients are administered either del-desiran or placebo (1:1) every eight weeks. HARBOR is designed to assess multiple key functional aspects of DM1. The primary endpoint is video hand opening time (vHOT), a measurement of myotonia, which is a hallmark symptom of DM1. Key secondary endpoints include muscle strength as measured by hand grip strength and quantitative muscle testing (QMT) total score, and activities of daily living as measured by DM1-Activ. All study participants, regardless of whether they receive active treatment or placebo, have the option to enroll into an open-label extension trial that is expected to begin in Q3 2025. For more information about the HARBOR trial, visit the HARBOR study website or visit http://www.clinicaltrials.gov and search for NCT06411288.
About Myotonic Dystrophy Type 1
Myotonic dystrophy type 1 (DM1) is a rare, hereditary (autosomal dominant), progressive neuromuscular disease that shortens life expectancy and requires life-long care caused by a triplet-repeat in the DMPK gene, resulting in a toxic gain of function mRNA. The disease is highly variable with respect to severity, presentation and age of onset, however, all forms of DM1 are associated with high levels of disease burden. DM1 is characterized by multisystemic manifestations including myotonia and progressive muscle weakening and may be underrecognized because it presents heterogeneously across skeletal, cardiac, and smooth muscles, leading to impairment of the cardiovascular, gastrointestinal, respiratory, ocular, and/or endocrine systems. Currently, there are no approved drugs for people living with DM1.
About del-desiran
Del-desiran, utilizing Avidity's AOC platform technology, is designed to address the genetic cause of DM1 by reducing levels of toxic DMPK mRNA. Del-desiran consists of a proprietary monoclonal antibody that binds to transferrin receptor 1 (TfR1) and is conjugated to a siRNA that targets DMPK mRNA. Del-desiran is currently being assessed in the global Phase 3 HARBOR™ trial and in the ongoing MARINA-OLE™ trial in people with DM1. Long-term data from the MARINA-OLE trial showed reversal of disease progression in people living with DM1 across multiple endpoints including video hand opening time (vHOT) as a measure of hand function and myotonia, muscle strength and activities of daily living when compared to END-DM1 natural history data. Del-desiran has received Breakthrough Therapy, Orphan Drug and Fast Track designations by the
About Avidity
Avidity Biosciences, Inc.'s mission is to profoundly improve people's lives by delivering a new class of RNA therapeutics - Antibody Oligonucleotide Conjugates (AOCs™). Avidity is revolutionizing the field of RNA with its proprietary AOCs, which are designed to combine the specificity of monoclonal antibodies with the precision of oligonucleotide therapies to address targets and diseases previously unreachable with existing RNA therapies. Utilizing its proprietary AOC platform, Avidity demonstrated the first-ever successful targeted delivery of RNA into muscle and is leading the field with clinical development programs for three rare muscle diseases: myotonic dystrophy type 1 (DM1), Duchenne muscular dystrophy (DMD) and facioscapulohumeral muscular dystrophy (FSHD). Avidity is also advancing two wholly-owned precision cardiology development candidates addressing rare genetic cardiomyopathies. In addition, Avidity is broadening the reach of AOCs with its advancing and expanding pipeline including programs in cardiology and immunology through key partnerships. Avidity is headquartered in San Diego, CA. For more information about our AOC platform, clinical development pipeline and people, please visit www.aviditybiosciences.com and engage with us on LinkedIn and X.
Forward-Looking Statements
Avidity cautions readers that statements contained in this press release regarding matters that are not historical facts are forward-looking statements. These statements are based on the company's current beliefs and expectations. Such forward-looking statements include, but are not limited to, statements regarding: the characterization of data associated with del-desiran, and the impact of such data on the advancement of the del-desiran; the status of the global Phase 3 HARBOR™ trial, including but not limited to enrollment, design and goals; the regulatory status of a registrational path for del-desiran; Avidity's plans to release topline data from the HARBOR trial and the timing thereof; and Avidity's plans to submit marketing applications for del-desiran and the timing thereof.
The inclusion of forward-looking statements should not be regarded as a representation by Avidity that any of these plans will be achieved. Actual results may differ from those set forth in this press release due to the risks and uncertainties inherent in Avidity's business and beyond its control, including, without limitation: preliminary results of a clinical trial are not necessarily indicative of final results; further analysis of existing clinical data and analysis of new data may lead to conclusions different from those established as of the respective data cutoff dates in Avidity's clinical study of del-desiran, and such data may not meet Avidity's expectations; unexpected adverse side effects to, or inadequate efficacy of, del-desiran that may delay or limit its development, regulatory approval and/or commercialization; later developments with the FDA and other global regulators that could be inconsistent with the feedback received to date regarding del-desiran and could affect the timing or likelihood of its potential approval; Avidity's approach to the discovery and development of product candidates based on its AOC™ platform is unproven; potential delays in the data readouts and completion of the HARBOR trial; Avidity's dependence on third parties in connection with clinical testing and product manufacturing; legislative, judicial and regulatory developments in
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FAQ
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