A Clinical Study of PGN-EDODM1 in People With Myotonic Dystrophy Type 1 (FREEDOM2-DM1)

April 23, 2026 updated by: PepGen Inc

A Phase 2 Randomized, Double-Blind, Placebo-Controlled, Multiple Ascending Dose Study of PGN-EDODM1 in Adult Participants With Myotonic Dystrophy Type 1 (FREEDOM2-DM1)

The purpose of this study is to learn about the effects of an investigational medicine, PGN-EDODM1, to see how safe and tolerable multiple administrations of PGN-EDODM1 are for people with myotonic dystrophy type 1 (DM1) compared to placebo.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Estimated)

24

Phase

  • Phase 2

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

  • Canada
    • Alberta
      • Calgary, Alberta, Canada, T2N 4Z6
    • Ontario
      • Ottawa, Ontario, Canada
        • Recruiting
        • Ottawa Hospital Research Institute (OHRI)
        • Contact:
    • Quebec
      • Chicoutimi, Quebec, Canada
      • Montreal, Quebec, Canada, H3A 2B4
        • Recruiting
        • Montreal Neurological Institute
        • Contact:
  • New Zealand
    • Auckland
      • Takapuna, Auckland, New Zealand, 0622
        • Active, not recruiting
        • Pacific Clinical Research Network Auckland
  • United Kingdom
      • Newcastle upon Tyne, United Kingdom, NE7 7DN
        • Recruiting
        • Newcastle Upon Tyne Hospitals
        • Contact:
    • England
      • Salford, England, United Kingdom
    • UK
      • London, UK, United Kingdom
        • Recruiting
        • University College London Hospitals Nhs Foundation Trust
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child
  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Confirmed diagnosis of DM1, as defined as having a repeat sequence in the DMPK gene with at least 100 CTG repeats
  • Presence of myotonia
  • Have sufficient muscle mass in bilateral tibialis anterior (TA) muscles that a needle biopsy can safely be performed
  • Body Mass Index (BMI) of < 35.0 kg/m^2

Exclusion Criteria:

  • Congenital DM1
  • Known history or presence of any clinically significant conditions that may interfere with study safety assessments
  • Abnormal laboratory tests at screening considered clinically significant by the Investigator
  • Medications specific for the treatment of myotonia within 2 weeks prior to screening
  • Percent predicted forced vital capacity (FVC) <40%
  • Use of an investigational drug, device, or product within 30 days of 5 half-lives of the study drug (whichever is longer) prior to Screening

Note: Other inclusion and exclusion criteria may apply.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Quadruple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: PGN-EDODM1
Participants will be randomized to receive ascending doses of PGN-EDODM1, once every 4 weeks (Q4W) for 12 weeks
Drug: PGN-EDODM1
Administered by intravenous (IV) infusion
Placebo Comparator: Placebo
Participants randomized to the placebo arm will receive doses of saline (0.9% NaCl), once every 4 weeks (Q4W) for 12 weeks
Other: Placebo
Administered by intravenous (IV) infusion

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Safety and tolerability as assessed by number of participants with Adverse Events (AEs)
Time Frame: Baseline through Day 112
Baseline through Day 112

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Maximum Observed Plasma Drug Concentration (Cmax) of PGN-EDODM1
Time Frame: Day 1 through Day 84
Day 1 through Day 84
Time to Maximum Observed Plasma Drug Concentration (Tmax) of PGN-EDODM1
Time Frame: Day 1 through Day 84
Day 1 through Day 84
Apparent Terminal Half-Life (t½) of PGN-EDODM1
Time Frame: Day 1 through Day 84
Day 1 through Day 84
Area Under the Concentration-time Curve of PGN-EDODM1
Time Frame: Day 1 through Day 84
Day 1 through Day 84
Change in splicing index in skeletal muscle tissue
Time Frame: Baseline through Day 91
Baseline through Day 91
Change in myotonia as measured by video Hand Opening Time (vHOT)
Time Frame: Baseline through Day 112
Baseline through Day 112
Hand grip strength
Time Frame: Baseline through Day 112
by dynamometer
Baseline through Day 112
Change in mobility as measured by 10 meter walk/run time
Time Frame: Baseline through Day 112
Baseline through Day 112

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

PepGen Inc

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

December 10, 2024

Primary Completion (Estimated)

March 1, 2027

Study Completion (Estimated)

March 1, 2027

Study Registration Dates

First Submitted

October 22, 2024

First Submitted That Met QC Criteria

October 29, 2024

First Posted (Actual)

October 31, 2024

Study Record Updates

Last Update Posted (Actual)

April 28, 2026

Last Update Submitted That Met QC Criteria

April 23, 2026

Last Verified

April 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • PGN-EDODM1-102

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Myotonic Dystrophy 1

Clinical Trials on Placebo

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Algeria

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe