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

Status

Indicates the current recruitment status or the expanded access status.
Active, not recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
47

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • 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 Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

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 Politécnico 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

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

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

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
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

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
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

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
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

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
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)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
February 20, 2024

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
February 2, 2027

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
February 2, 2027

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
December 15, 2023

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
December 15, 2023

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
December 29, 2023

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
August 20, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
August 19, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
August 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant 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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