CClinicalTrials.gg
CompletedNCT06411288HARBORUpdated Sep 1, 2026

Global Study of Del-desiran for the Treatment of DM1

A Phase 3 interventional study of AOC 1001 (del-desiran) and Placebo in DM1, Myotonic Dystrophy and Myotonic Dystrophy 1, sponsored by Avidity Biosciences, Inc.. Completed at 34 sites in 10 countries. Open to participants aged 16 Years to 65 Years. Per ClinicalTrials.gov, last updated 2026-09-01.

Sponsored by Avidity Biosciences, Inc. · Phase 3, Interventional, and Treatment

Phase
Phase 3
Study type
Interventional
Enrollment
159
Allocation
Randomized
Ages
16 Years to 65 Years
Sex
All
01

Study summary

A Phase 3 Randomized, Double-Blind, Placebo-Controlled, Global Study to Evaluate the Efficacy and Safety of Intravenous Delpacibart Etedesiran (abbreviated del-desiran, formerly AOC 1001) for the Treatment of Myotonic Dystrophy Type 1

Read the detailed description

The study consists of a Screening Period of up to 6 weeks and 54-week Treatment Period. The anticipated duration is approximately 60 weeks.

Participants will be randomized to receive an intravenous infusion of either del-desiran or placebo at the clinical study site every 8 weeks for a total of 7 doses. The final dose will occur at Week 48, followed by a final assessment at Week 54.

After completion of Week 54 assessments, eligible participants will have the option to enroll into an open label extension (OLE) study, pending regulatory approval.

An Independent Data Monitoring Committee (IDMC) comprised of members independent and external to the Sponsor will review safety, tolerability, and efficacy (as needed) data of this study at regular intervals.

02

Conditions studied

  • DM1
  • Myotonic Dystrophy
  • Myotonic Dystrophy 1
  • Myotonia
  • Myotonic Dystrophy Type 1 (DM1)
  • Dystrophy Myotonic
  • Myotonic Disorders
  • Steinert Disease
  • Steinert
  • Myotonic Muscular Dystrophy

Keywords

  • DM1
  • Myotonic Dystrophy
  • Myotonic Dystrophy 1
  • Myotonia
  • Myotonic Dystrophy Type 1 (DM1)
  • Dystrophy Myotonic
  • Myotonic Disorders
  • Steinert Disease
  • Steinert
  • Myotonic Muscular Dystrophy
  • HARBOR
  • Avidity Biosciences
  • Avidity
  • AOC 1001
  • Del-desiran
  • Delpacibart etedesiran
03

Who can participate

Ages eligible
16 Years to 65 Years
Sexes eligible
All
Accepts healthy volunteers
No

Eligibility criteria

Key Inclusion Criteria:

  • Clinical and genetic diagnosis (CTG repeat ≥ 100) of DM1
  • Ability to walk independently (orthoses and ankle braces allowed) for at least 10 meters at screening

Key Exclusion Criteria:

  • Breastfeeding, pregnancy, or intent to become pregnant during the study
  • Unwilling or unable to comply with contraceptive requirements
  • Abnormal lab values, conditions or diseases that would make the participant unsuitable for the study
  • Diabetes that is not adequately controlled
  • History of decompensated heart failure within 3 months of screening. Participants with preexisting pacemaker/ICD are not excluded.
  • Body Mass Index > 35 kg/m2 at Screening
  • Recently treated with an investigational drug or biological agent
  • Treatment with anti-myotonic medication within 5 half-lives or 14 days of baseline, whichever is longer, prior to baseline.

Note: Additional protocol defined Inclusion and Exclusion criteria apply

04

Study design

Phase
Phase 3
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Quadruple (Participant, Care provider, Investigator, Outcomes assessor)
Enrollment
159 participants (actual)

Study arms

  • Experimental
    Del-desiran

    Del-desiran (AOC 1001) will be administered seven times

    Drug: AOC 1001 (del-desiran)

  • Placebo comparator
    Placebo

    Saline will be administered seven times

    Drug: Placebo

Interventions

  • DrugAOC 1001 (del-desiran)

    Del-desiran will be administered by intravenous (IV) infusion.

  • DrugPlacebo

    Placebo will be administered by intravenous (IV) infusion.

05

What researchers measure

Primary outcomes

  1. Hand function

    video Hand Opening Time (vHOT)

    Time frame: Through Week 54

Secondary outcomes

  1. Hand grip strength

    by dynamometer

    Time frame: Through Week 54

  2. Quantitative Muscle Testing composite score

    by dynamometer

    Time frame: Through Week 54

  3. Myotonic Dystrophy Type 1 activity and participation scale c

    Time frame: Through Week 54

  4. 10-Meter Walk/Run Test

    Time (in seconds) to walk or run 10 meters

    Time frame: Through Week 54

06

Study locations

34 sites
  • Stanford University
    Stanford, California 94305, United States
  • University of Colorado
    Denver, Colorado 80045, United States
  • University of Florida
    Gainesville, Florida 32608, United States
  • University Research Center of South Florida
    Tampa, Florida 33612, United States
  • Indiana University (IU)
    Indianapolis, Indiana 46202, United States
  • Kansas University Medical Center
    Kansas City, Kansas 66205, United States
  • Kennedy Krieger Institute
    Baltimore, Maryland 21205, United States
  • Beth Israel Deaconess Medical Center
    Boston, Massachusetts 02215, United States
  • University of Minnesota
    Minneapolis, Minnesota 55455, United States
  • University of Rochester Medical Center
    Rochester, New York 14642, United States
  • Duke University Medical Center
    Durham, North Carolina 27708, United States
  • Wake Forest
    Winston-Salem, North Carolina 27157, United States
  • University of Cincinnati Gardner Neuroscience Institute
    Cincinnati, Ohio 45219, United States
  • Ohio State University
    Columbus, Ohio 43221, United States
  • University of Pennsylvania
    Philadelphia, Pennsylvania 19104, United States
  • Houston Methodist Neurological Institute
    Houston, Texas 77030, United States
  • Virginia Commonwealth University
    Richmond, Virginia 23298, United States
  • University of Washington
    Seattle, Washington 98104, United States
  • The Ottawa Hospital
    Ottawa, Ontario K1Y 4E9, Canada
  • Montreal Neurological Institute
    Montreal, Quebec H3A 2B4, Canada
  • Aarhus University Hospital
    Aarhus N, 8200, Denmark
  • Rigshospitalet
    Copenhagen, 2100, Denmark
  • AP-HP Hopital Pitie-Salpetriere
    Paris, 75013, France
  • Klinikum der Ludwig-Maximilians-Universitaet Muenchen
    Munich, 80336, Germany
  • Fondazione Serena Onlus - Centro Clinico NeMO Milano
    Milan, 20162, Italy
  • Aomori Hospital
    Aomori, Aomori 038-1331, Japan
  • National Hospital Organization Osaka Toneyama Medical Center
    Osaka, 560-8552, Japan
  • Osaka University Hospital
    Osaka, 565-0871, Japan
  • National Center of Neurology and Psychiatry
    Tokyo, 187-8551, Japan
  • Maastricht University Medical Center
    Maastricht, 6229 HX, Netherlands
  • Stichting Radboud Universitair Medisch Centrum
    Nijmegen, 6525 GA, Netherlands
  • Hospital Universitario Donostia
    Donostia / San Sebastian, 20014, Spain
  • University College London Hospital
    London, NW1 2BU, United Kingdom
  • St. Georges University Hospitals NHS Foundation Trust
    London, SW17 0QT, United Kingdom
07

References and documents

Individual participant data

Plan to share: Undecided

No publications or documents are linked to this record.

08

Registry details

Key details

Study ID
NCT06411288
Lead sponsor
Avidity Biosciences, Inc.
Responsible party
Sponsor
First posted
May 13, 2024
Start date
May 30, 2024
Primary completion
Jul 23, 2026
Completion
Jul 29, 2026
Last update
Sep 1, 2026

Oversight

Data monitoring committee
Yes
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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