A Phase 1/2 Study of VX-670 in Adult Participants With Myotonic Dystrophy 1 (DM1) (Galileo)

August 19, 2026 updated by: Vertex Pharmaceuticals Incorporated

A Phase 1/2, Randomized, Double-blind, Placebo-controlled Single- and Multiple-dose Escalation Study Evaluating the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of VX-670 in Adult Subjects With Myotonic Dystrophy Type 1

The purpose of the study is to evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of VX-670 at different single and multiple doses in participants with DM1.

Study Overview

Status

Active, not recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Actual)

47

Phase

  • Phase 2
  • Phase 1

Contacts and Locations

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

Study Locations

  • Australia
      • Auchenflower, Australia
        • Wesley Research Institute
      • Melbourne, Australia
        • Neuroscience Clinical Trials Unit, Alfred Brain
  • Belgium
      • Leuven, Belgium
        • Universitaire Ziekenhuizen Leuven - Campus Gasthuisberg
  • Canada
      • Chicoutimi, Canada
        • Hôpital de Chicoutimi
      • Montreal, Canada
        • McGill University
      • Montreal, Canada
        • Altasciences Montreal
      • Ottawa, Canada
        • University of Ottawa
      • Québec, Canada
        • CHU Research Centre of Quebec
  • France
      • Paris, France
        • Neuromuscular Reference Center Institute of Myology
  • Germany
      • München, Germany
        • Ludwig Maximilians Universitaet Muenchen
  • Italy
      • Milan, Italy
        • Centro Clinico NeMO
  • Netherlands
      • Maastricht, Netherlands
        • Maastricht University Medical Center
  • Spain
      • Valencia, Spain
        • Hospital Universitario Y Politecnico La Fe
  • United Kingdom
      • Glasgow, United Kingdom
        • Clinical Research Facility, Queen Elizabeth University Hospital
      • London, United Kingdom
        • St. George's University Hospital
      • London, United Kingdom
        • Leonard Wolfson Experimental Neurology Centre CRF
      • Salford, United Kingdom
        • Salford Royal Hospital
      • Sheffield, United Kingdom
        • Royal Hallamshire Hospital
  • United States
    • California
      • San Carlos, California, United States, 94070
        • Stanford Neuromuscular Research
    • Florida
      • Gainesville, Florida, United States, 32608
        • University of Florida Clinical Research Center
    • Kansas
      • Fairway, Kansas, United States, 66205
        • University of Kansas Medical Center
    • Massachusetts
      • Boston, Massachusetts, United States, 02115
        • Boston Children's Hospital
    • Missouri
      • St Louis, Missouri, United States, 63110
        • Washington University School of Medicine / St. Louis Children's Hospital
    • North Carolina
      • Winston-Salem, North Carolina, United States, 27104
        • Wake Forest Baptist Health
    • Pennsylvania
      • Philadelphia, Pennsylvania, United States, 19104
        • University of Pennsylvania
    • Virginia
      • Richmond, Virginia, United States, 23298
        • Virginia Commonwealth University (Sanger Hall)

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

  • Adult

Accepts Healthy Volunteers

No

Description

Key Inclusion Criteria:

- Documented clinical diagnosis of DM1 with age of onset greater than (>) 1 year of age and documented positive genetic test for DM1 in the subject with cytosine thymine guanine (CTG) repeat of at least 100

Key Exclusion Criteria:

- History of any illness or any clinical condition as pre-specified in the protocol

Other protocol defined Inclusion/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: Sequential Assignment
  • Masking: Quadruple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Part A: Single Ascending Dose
Participants will be randomized to receive a single dose of different dose levels of VX-670.
Drug: VX-670
Solution for intravenous administration.
Placebo Comparator: Part A: Placebo
Participants will be randomized to receive single dose of placebo matched to VX-670.
Drug: Placebo
Solution for intravenous administration.
Experimental: Part B: Single and Multiple Ascending Dose
Participants will be randomized to receive single and multiple doses of different dose levels of VX-670. The dose levels will be determined based on the data from Part A.
Drug: VX-670
Solution for intravenous administration.
Placebo Comparator: Part B: Placebo
Participants will be randomized to receive single or multiple doses of placebo matched to VX-670.
Drug: Placebo
Solution for intravenous administration.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Parts A and B: Safety and Tolerability as Assessed by Number of Participants With Adverse Events (AEs)
Time Frame: Part A: From Baseline up to Day 42; Part B: From Baseline and up to Day 168
Part A: From Baseline up to Day 42; Part B: From Baseline and up to Day 168

Secondary Outcome Measures

Outcome Measure
Time Frame
Part A: Maximum Observed Concentration (Cmax) of VX-670 and its Active Component in Plasma
Time Frame: From Day 1 up to Day 42
From Day 1 up to Day 42
Part A: Area Under the Concentration Versus Time Curve (AUC) of VX-670 and its Active Component in Plasma
Time Frame: From Day 1 up to Day 42
From Day 1 up to Day 42
Part B: Maximum Observed Concentration (Cmax) of VX-670 and its Active Component in Plasma After Each Dose
Time Frame: From Day 1 up to Day 168
From Day 1 up to Day 168
Part B: Area Under the Concentration Versus Time Curve (AUC) of VX-670 and its Active Component in Plasma After Each Dose
Time Frame: From Day 1 up to Day 168
From Day 1 up to Day 168
Part B: Concentration of VX-670 and its Active Component in Muscle
Time Frame: Baseline, Day 15 and Day 120
Baseline, Day 15 and Day 120
Part B: Change in Splicing Index in Muscle Biopsy
Time Frame: Baseline, Day 15 and Day 120
Baseline, Day 15 and Day 120

Collaborators and Investigators

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

Sponsor

Vertex Pharmaceuticals Incorporated

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)

February 20, 2024

Primary Completion (Estimated)

February 2, 2027

Study Completion (Estimated)

February 2, 2027

Study Registration Dates

First Submitted

December 15, 2023

First Submitted That Met QC Criteria

December 15, 2023

First Posted (Actual)

December 29, 2023

Study Record Updates

Last Update Posted (Actual)

August 20, 2026

Last Update Submitted That Met QC Criteria

August 19, 2026

Last Verified

August 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • VX23-670-001
  • 2023-506028-10-00 (Other Identifier: EUCT Number)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

Details on Vertex data sharing criteria and process for requesting access can be found at: https://www.vrtx.com/our-science/clinical-trials-data-sharing/

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

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.

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