Recruiting
Phase 1
Phase 2

ATX-01

Sponsor:

ARTHEx Biotech S.L.

Code:

NCT06300307

Conditions

Myotonic Dystrophy 1

Eligibility Criteria

Sex: All

Age: 18 - 64

Healthy Volunteers: Not accepted

Interventions

ATX-01

Placebo

Study Details

Brief summary:

The goal of this clinical trial is to test ATX-01 in participants with myotonic dystrophy type 1 (DM1). The main question it aims to answer is if ATX-01 is safe and well tolerated. The trial will compare the safety and tolerability of ATX-01 and a matching placebo.

There will be a single-ascending dose part of the trial and a multiple-ascending dose part. In the single-ascending dose, participants will receive one dose of ATX-01 or placebo. In the multiple-ascending dose part, participants will receive three doses of ATX-01 or placebo.

ATX-01 is a novel anti-miR (synthetic single stranded oligonucleotide) that inhibits a microRNA called miR-23b.

Conditions

Myotonic Dystrophy 1

Study ID

NCT06300307

Start date

Oct 15, 2024

Status verified date

Feb, 2026

Completion date

Jul, 2027

Anticipated

Primary completion date

Jul, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 64

Healthy Volunteers: Not accepted

Key Inclusion Criteria:

  • Participants with a documented clinical diagnosis of DM1 (CTG expansion of >150 repeats in DMPK gene measured in peripheral blood mononuclear cells)
  • Ambulatory, defined as able to complete a 10-meter walk/run test at screening without the use of assistive devices such as canes, walkers, or orthoses, except for ankle-foot orthoses
  • Presence for >3 seconds of grip myotonia as confirmed by a central reader

Key Exclusion Criteria:

  • Participants with congenital DM1
  • Medical Research Council Muscle Scale score of less than 4 on ankle dorsiflexion or significant tibialis anterior atrophy that prevents a muscle biopsy
  • Use of mexiletine or other agent for myotonia within 21 days or 5 half-lives, whichever is longer, prior to screening

Study Design

Enrollment

56 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: ATX-01

ATX-01 is a formulation of the anti-microRNA 23b (anti-miR-23b), known as X82108, a novel type of antisense oligonucleotide

placebo comparator: Placebo

Placebo to ATX-01

Interventions

ATX-01

Solution for infusion

Placebo

Solution for infusion

Primary outcome measure

  • Incidence of adverse events [ Time Frame: Up to 120 days ]

Central Contacts and Locations

Central contacts

Project Manager

+34676229821clinical@arthexbiotech.com

Locations

UCLA

Recruiting

Los Angeles, California, United States, 90095

Contacts

Michael Yan

310-825-3264MYan@mednet.ucla.edu

Principal Investigator:

Perry Shieh, MD, PhD

University of Florida

Recruiting

Gainesville, Florida, United States, 32610

Contacts

Brandy Donahue-Quails

Brandy.Donahue-Quails@neurology.ufl.edu

University of Iowa Health Care - Department of Neurology

Recruiting

Iowa City, Iowa, United States, 52242

Contacts

Heena Olalde

319-356-8326heena-olalde@uiowa.edu

Principal Investigator:

Andrea Swenson

University of Kansas Medical Center, Department of Neurology

Recruiting

Fairway, Kansas, United States, 66205

Contacts

Cassidy Nelson

913-588-3653cnelson15@kumc.edu

Virginia Commonwealth University

Recruiting

Richmond, Virginia, United States, 23298

Contacts

Jodie Howell

804-828-6110jodie.howell@vcuhealth.org

Principal Investigator:

Nicholas Johnson, MD

Centre Intégré Universitaire de Santé et Services Sociaux du Saguenay-Lac-St-Jean

Recruiting

Chicoutimi, Quebec, Canada, G7H 5H6

Contacts

Sabrina Côté

418-541-1000sabrina.cote.inf@ssss.gouv.qc.ca

More Information

Sponsor

ARTHEx Biotech S.L.

Last update posted

Feb 10, 2026

Last verified

Feb, 2026

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-09. This information was provided to ClinicalTrials.gov by ARTHEx Biotech S.L. on 2026-02-10.