Skip to main content
OpenTrials
Enrolling by Invitation

NCT Number: NCT06926621

A Study of Long-term Safety and Efficacy of VX-670 in Participants With Myotonic Dystrophy Type I

The purpose of the study is to evaluate the long-term safety and tolerability, efficacy and pharmacokinetics of VX-670 in participants with Myotonic Dystrophy Type I (DM1).

Enrolling by Invitation

Interested in participating?

Request Info

Key information

Conditions

Myotonic Dystrophy Type 1 (DM1) Congenital, Hereditary, and Neonatal Diseases and Abnormalities Genetic Diseases, Inborn Heredodegenerative Disorders, Nervous System Muscular Diseases Muscular Disorders, Atrophic Muscular Dystrophies Musculoskeletal Diseases Myotonia Myotonic Disorders Myotonic Dystrophy Nervous System Diseases Neurodegenerative Diseases Neurologic Manifestations Neuromuscular Diseases Neuromuscular Manifestations Pathological Conditions, Signs and Symptoms Signs and Symptoms

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 2

Primary location

Wesley Research Institute, Auchenflower, Australia

Loading trial locations.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Key Inclusion Criteria:

  • Completed study drug treatment in parent study VX23-670-001 (NCT06185764)

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.

Treatment and study plan

VX-670

Drug

Solution for intravenous administration.

Primary outcomes

  1. Safety and Tolerability as Assessed by Number of Participants With Adverse Events (AEs) and Serious Adverse Events (SAEs)

    Time frame: From Day 1 up to Week 108

Secondary outcomes

  1. Maximum Observed Concentration (Cmax) of VX-670 and its Active Component in Plasma

    Time frame: From Day 1 up to Week 96

  2. Area Under the Concentration Versus Time Curve (AUC) of VX-670 and its Active Component in Plasma

    Time frame: From Day 1 up to Week 96

Sponsors and collaborators

Lead sponsor

Vertex Pharmaceuticals Incorporated

Industry

Registry information

Official study title

An Open-label Extension Study Evaluating the Long-term Safety, Tolerability, Efficacy, Pharmacokinetics, and Pharmacodynamics of VX-670 in Adult Subjects With Myotonic Dystrophy Type I

Important dates

Study start
2025
Primary completion
2029
Study completion
2029
First posted
Apr 14, 2025
Registry last updated
Jun 30, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.