A 2-Part, Randomized, Double-Blind, Placebo-Controlled Study in Participants with Duchenne Muscular Dystrophy Amenable to Exon 45 Skipping to Evaluate the Safety and Efficacy of ENTR-601-45 (ELEVATE-45)

Prior treatment

• Any significant concomitant medical condition that interfere with the ability to comply with protocol requirements
• Has an acute illness within 4 weeks prior to the first dose of study drug which may interfere with study measurements or jeopardize participant’s safety
• Received any experimental or investigational drug, etc. within 3 months prior to first dose or within 5 half-lives (whichever is longer).
• Use of any pharmacologic treatment, other than stable corticosteroids, that might have had an effect on muscle strength or function during the study (eg, growth hormone, testosterone).

Lab values

• Use of the following medications: a. Prior or current treatment with any exon skipping therapy within the previous 12 months b. Prior or current treatment with any gene therapy c. Use of anti-coagulants, anti-thrombotics, or anti-platelet agents d. Use of immunosuppressants (other than systemic or oral corticosteroids for chronic non-DMD conditions) e. Treatment with a histone deacetylase (HDAC) inhibitor, including (but not limited to) givinostat
• Laboratory abnormalities
• Has an abnormal electrocardiogram (ECG) reading assessed as clinically significant by the investigator, and/or a QT interval with Fridericia correction method (QTcF) >450 msec at Screening or prior to the first dose of study drug on Day 1.

Other

• Daytime ventilator dependence, or any use of invasive mechanical ventilation via tracheostomy.
• Other protocol-defined criteria apply.

• Genetic diagnosis of DMD and confirmed pathologic variant in the dystrophin gene that is amenable to exon 45 skipping as reviewed by a central genetic counselor.
• Assigned male at birth with clinical signs compatible with Duchenne muscular dystrophy as determined by the investigator.
• Part A: 4-20 years of age
• Ambulatory Status Part A: ambulatory with a specific Performance of the Upper Limb v2.0 (PUL 2.0) Entry item at Screening
• Adequate muscle for obtaining tissue biopsy as assessed by the investigator.
• Other protocol-defined criteria apply