Overview
The primary purpose of the study is to evaluate the safety and tolerability of single intravenous (IV) doses of PGN-EDODM1 administered to participants with Myotonic Dystrophy Type 1 (DM1).
The study consists of 2 periods: A Screening Period (up to 30 days) and a Treatment and Observation Period (16 weeks).
Eligibility
Inclusion Criteria:
- Confirmed diagnosis of DM1, as defined as having a repeat sequence in the DMPK gene with at least 100 CTG repeats
- Medical Research Council (MRC) score of ≥ Grade 4- in bilateral tibialis anterior (TA) muscles (the ability to move through full range of motion and hold against at least moderate pressure from the examiner)
- Presence of myotonia
Exclusion Criteria:
- Congenital DM1
- Known history or presence of any clinically significant conditions that may interfere with study safety assessments
- Abnormal laboratory tests at screening
- Medications specific for the treatment of myotonia within 2 weeks prior to screening
- Percent predicted forced vital capacity (FVC) <40%
Note: Other inclusion and exclusion criteria may apply.
