Study to Assess the Safety and Efficacy of Viltolarsen in Ambulant Boys With DMD (RACER53-X)

Study Overview
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Brief Summary
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This is a Phase 3, multi-center, open-label extension study in ambulant boys with DMD who have completed the 48-week treatment period of either viltolarsen or placebo in Study NS-065/NCNP-01-301.

Detailed Description
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This Phase 3 study is a multi-center, open-label extension study in ambulant boys with DMD who have completed the 48-week treatment period of either viltolarsen or placebo in Study NS-065/NCNP-01-301. Patients will receive viltolarsen administered IV at weekly doses of 80 mg/kg. Study NS-065/NCNP-01-302 will be comprised of a 96-week treatment period.

Official Title
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A Phase 3, Multi-center, Open-label Extension Study to Assess the Safety and Efficacy of Viltolarsen in Ambulant Boys With Duchenne Muscular Dystrophy (DMD)

Conditions
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Duchenne Muscular Dystrophy

Intervention / Treatment
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* Drug: Viltolarsen


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patient has completed the NS-065/NCNP-01-301 study; Patient's parent(s) or legal guardian(s) has (have) provided written informed consent and Health Insurance Portability and Accountability Act authorization, where applicable, prior to any study-related procedures; patients will be asked to give written or verbal assent according to local requirements; Patient and parent(s)/guardian(s) are willing and able to comply with scheduled visits, investigational product (IP) administration plan, and study procedures. Exclusion Criteria: Patient had an adverse event in Study NS-065/NCNP-01-301 that, in the opinion of the investigator and/or the sponsor, precludes safe use of viltolarsen for the patient in this study; Patient had a treatment which was made for the purpose of dystrophin or dystrophin-related protein induction after completion of Study NS-065/NCNP-01-301; Patient took any other investigational drug(s) during or after completion of Study NS-065/NCNP-01-301; Patient is judged by the investigator and/or the sponsor not to be appropriate to participate in the extension study for any reason.
Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Viltolarsen<br>Patients amenable to exon 53 skipping will receive viltolarsen intravenous (IV) infusions, weekly, at 80 mg/kg for up to 96 weeks. | Drug: Viltolarsen<br>* Received during weekly intravenous infusions<br>* Other names: NS-065/NCNP-01;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of participants with treatment related Adverse Events as assessed by CTCAE v4.03 |  | baseline to up to 96 weeks of treatment | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to Stand Test (TTSTAND) | Change in Time to Stand | baseline to 96 weeks of treatment | 
| Time to Run/Walk 10 Meters Test (TTRW) | Change in Time to Run/Walk 10 meters | baseline to 96 weeks of treatment | 
| Six-minute Walk Test (6MWT) | Change in Six-minute Walk | baseline to 96 weeks of treatment | 
| North Star Ambulatory Assessment (NSAA) | Change in North Star Ambulatory Assessment | baseline to 96 weeks of treatment | 
| Time to Climb 4 Stairs Test (TTCLIMB) | Change in Time to Climb 4 Stairs | baseline to 96 weeks of treatment | 
| Muscle Strength Measured by Hand-Held Dynamometer | Change in Muscle Strength Measured by Hand-Held Dynamometer | baseline to 96 weeks of treatment |