Study of SRP-1003 in Participants With Type 1 Myotonic Dystrophy

Sarepta Therapeutics

Status and phase: Enrolling; Phase 2; Phase 1

Conditions: Myotonic Dystrophy 1

Treatments: Drug: Placebo SC Injection; Drug: SRP-1003 SC Injection; Drug: Placebo IV Infusion; Drug: SRP-1003 IV Infusion

Study type: Interventional

Funder types: Industry

Identifiers

NCT06138743

SRP-1003-101

2024-513579-42 (EudraCT Number)

Details and patient eligibility

About

This is a phase 1/2a double-blinded, placebo-controlled, dose-escalating study to evaluate the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics of single and multiple ascending doses of SRP-1003 compared to placebo in male and female participants with type 1 myotonic dystrophy (DM1). Participants who have provided written informed consent and met all protocol eligibility requirements will be randomized to receive single (Part 1) or multiple (Part 2) doses of SRP-1003 or placebo.

Enrollment: 78 estimated patients

Sex: All

Ages: 18 to 65 years old

Volunteers: No Healthy Volunteers

Inclusion and exclusion criteria

Key Inclusion Criteria:

• Genetically confirmed diagnosis of DM1
• Clinician-assessed signs of DM1 including clinically apparent myotonia
• Onset of DM1 symptoms occurred after the age of 12 years
• Walk for at least 10 meters independently at screening
• Participants of childbearing potential must agree to use highly effective contraception in addition to a condom during the study and for at least 90 days following the end of study or last dose of study drug, whichever is later. Participants must not donate sperm or eggs during the study and for at least 90 days following the end of study or last dose of study drug whichever is later.

Key Exclusion Criteria:

• Inadequately controlled diabetes
• Confirmed diagnosis of congenital DM1
• Uncontrolled hypertension
• History of tibialis anterior (TA) biopsy within 3 months of Day 1 or planning to undergo TA biopsies during the study period
• Clinically significant cardiac, liver or renal disease
• Human immunodeficiency virus infection (seropositive) at screening
• Seropositive for hepatitis B or hepatitis C at screening
• Untreated or poorly controlled epilepsy
• Treatment with anti-myotonia medication within a period of 5 half-lives of the medication prior to screening.
• Abnormal coagulation parameters at screening including platelet count, international normalized ratio, prothrombin time, and activated partial thromboplastin time

Note: Additional inclusion/exclusion criteria may apply per protocol

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Quadruple Blind

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78 participants in 4 patient groups, including a placebo group

SRP-1003 IV Infusion

Experimental group

Description:

Single or multiple doses of SRP-1003 by intravenous (IV) infusion

Treatment:

Drug: SRP-1003 IV Infusion

Placebo by IV Infusion

Placebo Comparator group

Description:

Single or multiple doses of placebo by IV infusion

Treatment:

Drug: Placebo IV Infusion

SRP-1003 SC Injection

Experimental group

Description:

Single or multiple doses of SRP-1003 by subcutaneous (SC) injection

Treatment:

Drug: SRP-1003 SC Injection

Placebo by SC Injection

Placebo Comparator group

Description:

Single or multiple doses of placebo by SC injection

Treatment:

Drug: Placebo SC Injection