Recruiting
Phase 1
Phase 2

SAR446268

Sponsor:

Sanofi

Code:

NCT06844214

Conditions

Myotonic Dystrophy

Eligibility Criteria

Sex: All

Age: 10 - 55

Healthy Volunteers: Not accepted

Interventions

SAR446268

Study Details

Brief summary:

This is a Phase 1/Phase 2 open-label single arm, multicenter, and multinational study with SAR446268 for treatment of male and female participants 10 to 55 years old with non-congenital myotonic dystrophy (DM) type 1 (DM1).

The purpose of this study is to evaluate the safety and efficacy of SAR446268 in knocking down dystrophia myotonica protein kinase (DMPK) messenger ribonucleic acid (mRNA) levels and improving neuromuscular function in DM1 participants receiving a single intravenous (IV) administration of SAR446268. The study consists of a dose escalation part (Part A) during which single ascending doses of SAR446268 will be evaluated in 3 distinct cohorts and an optional fourth dose cohort. Once a safe and effective dose is identified, additional participants will be treated in Part B, the dose expansion phase of the study.

The study duration will be 112 weeks (approximately 2 years) for each participant in Parts A and B respectively and includes an optional pre-screening period, approximately 8-week screening phase and a 104-week follow-up period post-SAR446268 administration.

Conditions

Myotonic Dystrophy

Study ID

NCT06844214

Start date

Jul 23, 2025

Status verified date

Sep, 2026

Completion date

Apr 27, 2032

Anticipated

Primary completion date

Feb 28, 2029

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 10 - 55

Healthy Volunteers: Not accepted

Inclusion Criteria:

Participants are eligible to be included in the study only if all of the following criteria apply:

  • For Part A, participants must be 18 to 55 years of age inclusive, at the time of signing the informed consent.
  • For Part B, participants must be as follows:

  • 10 to 17 years of age inclusive, at the time of signing the informed consent or,
  • 18 to 55 years of age inclusive, at the time of signing the informed consent.
  • Participants with non-congenital onset DM1
  • Participants presenting with signs of DM1 including myotonia and muscle weakness, as diagnosed previously by a clinician based on medical history.
  • Participants with genetic diagnosis of DM1 \[cytosine-thymine-guanine (CTG) repeat length ≥50 in one allele from medical history\]
  • Participants who can walk independently for at least 10 meters at screening (orthoses and ankle braces allowed).

Exclusion Criteria:

Participants are excluded from the study if any of the following criteria apply:

  • Participants with neutralizing antibodies against the AAV.SAN011 capsid
  • Participants with left ventricular ejection fraction <50%
  • Participants with liver or biliary disease defined as having at least one of the following:

  • ALT >3 x ULN and AST >3 x ULN
  • Alkaline phosphatase >3 x ULN
  • Total bilirubin >1.5 x ULN (unless has a genetically confirmed diagnosis of Gilbert's syndrome)
  • Direct bilirubin ≥1.5 x ULN
  • Participants with International normalized ratio >1.5
  • Participants with renal disease defined as:

• Serum creatinine >1.5 x ULN and/or estimated glomerular filtration rate <60 mL/min/1.73 m2 as determined by Chronic Kidney Disease Epidemiology Collaboration (2021) for those age ≥18 years and Bedside Schwartz Equation for those <18 years
  • Participants with chronic respiratory insufficiency and on long term/hull-time ventilatory assistance requiring at least 6 hours per day for at least 21 consecutive days.
  • Participants with contraindication to corticosteroid or with conditions that could worsen in the presence of corticosteroids, as determined by the Investigator.
  • Participants with active hepatitis B or C infection; HBsAg (+), or HCV RNA (+), or current antiviral therapy for either.
  • Participants with HBcAb (+) who are not amenable for prophylactic anti-HBV therapy or pre-emptive therapy guided by serial HBV DNA monitoring during the corticosteroids therapy.
  • Participants at high risk for tuberculosis reactivation during the corticosteroids therapy as determined by the Investigator.
  • Participants with a known HIV infection
  • Participants with serious intercurrent illness that, in the opinion of the Investigator, would preclude participation in the study or potentially decrease survival.
  • Participants with recent history of or current drug or alcohol abuse in the past 12 months prior to screening.
  • Participants with history of tibialis anterior biopsy within 12 weeks from Day 1 or planning to undergo tibialis anterior biopsies during the duration of this clinical trial.
  • Participants with significant developmental delay, intellectual disability, or behavioral neuropsychiatric manifestations as determined by the Investigator.
  • Participants with previous systemic corticosteroids treatment at doses of >5 mg/day within 15 days of Day 1
  • Participants with previous treatment with anti-myotonic medication within 15 days of Day 1
  • Participants not suitable for participation, whatever the reason, as judged by the Investigator, including medical or clinical conditions, or participants potentially at risk of noncompliance to study procedures.
  • Participants who have been classified as severe cardiac risk by the Investigator.

The above information is not intended to contain all considerations relevant to a participant's potential participation in a clinical trial.

Study Design

Enrollment

32 participants

Anticipated

Intervention Model

Single group

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: SAR446268

Participants will receive a single dose of SAR446268 on Day 1

Interventions

SAR446268

Pharmaceutical form: Solution for infusion; Route of administration: IV infusion

Primary outcome measure

  • Part A and Part B: Incidence of treatment-emergent adverse events (TEAEs) following SAR446268 administration [ Time Frame: Baseline to Week 52 ]
  • Part B: Proportion of participants with at least 40% DMPK mRNA knockdown in muscle biopsy at Weeks 12 and 52 following SAR446268 administration [ Time Frame: Weeks 12 and 52 ]

Central Contacts and Locations

Central contacts

Trial Transparency email recommended (Toll free for US & Canada)

800-633-1610contact-us@sanofi.com

Locations

University of Florida, 2004 Mowry Road - Site Number: 8400005

Recruiting

Gainesville, Florida, United States, 32601

Contacts

Melissa Lewis

352-273-8219melissa.lewis@peds.ufl.edu

Principal Investigator:

Dr. Subramony

University of South Florida - Neuromuscular Research, 13330 USF Laurel Drive - Site Number: 8400001

Recruiting

Tampa, Florida, United States, 33612

Contacts

Sruthi Kommi Reddy

SKommiReddy@usf.edu

Principal Investigator:

Dr. Tuan Vu

Columbia University Medical Center - Neurological Institute, 710 W. 168th, 2nd floor, suite 204 - Site Number : 8400003

Recruiting

New York, New York, United States, 10032

Contacts

Jorge Cabrera

212-305-7462jec2273@cumc.columbia.edu

Principal Investigator:

Dr. Christina Ulane

Penn Medicine: University of Pennsylvania Health System- Site Number : 8400009

Recruiting

Philadelphia, Pennsylvania, United States, 19104

Virginia Commonwealth University Medical Center- Site Number : 8400006

Recruiting

Richmond, Virginia, United States, 23298

The Montreal Neurological Institute and Hospital, 3801 rue University - Site Number: 1240001

Recruiting

Montreal, Quebec, Canada, H3A 2B4

Contacts

514-398-5500nm.neurocru@mcgill.ca

Principal Investigator:

Dr. Erin O'Ferrall

More Information

Sponsor

Sanofi

Last update posted

Sep 21, 2026

Last verified

Sep, 2026

Trial information was received from ClinicalTrials.gov and was last updated on 2026-10-24. This information was provided to ClinicalTrials.gov by Sanofi on 2026-09-21. Recruitment status is synced daily from ClinicalTrials.gov and may not reflect the sponsor's current status. Confirm during your call.