Antioxidant Therapy in RYR1-Related Congenital Myopathy
Status:
Completed
Trial end date:
2018-05-30
Target enrollment:
Participant gender:
Summary
Background:
- Ryanodine receptor type 1-related myopathies (RYR1-RM) are the most common non-dystrophic
muscle diseases that people are born with in the U.S. They affect development, muscles, and
walking. Researchers want to test a new drug to help people with these diseases.
Objectives:
- To see if the drug N-acetylcysteine decreases muscle damage in people with RYR1-RM. To see
if it improves their exercise tolerance.
Eligibility:
- People age 7 and older with a confirmed genetic diagnosis of RYR1 or a clinical diagnosis
of RYR1 and a family member with a confirmed genetic diagnosis.
Design:
- Participants will be screened with a checklist of criteria. Adult participants may have
a muscle biopsy. A needle will remove a tiny piece of muscle in the lower leg.
- Study visits will take several days.
- Visit 1:
- Medical history
- Physical exam
- Blood, urine, and saliva tests
- Questions about symptoms and quality of life
- Heart, lung, and walking tests
- Muscle Oxygenation Capacity Test. A blood pressure cuff around the thigh will be
tightened for up to 10 minutes.
- Biodex testing, stretching the leg against resistance
- Muscle ultrasounds. A probe will be moved over the skin.
- Participants may be photographed or videotaped during procedures.
- They may have a muscle biopsy.
- Six months later, visit 2 will repeat visit 1. Participants will start taking the study
drug dissolved in water or placebo three times a day for 6 months.
- Participants will stay at NIH for 2 days after starting the study drug.
- Participants will be contacted by phone during the study to monitor side effects
- Six months after starting the study drug, study visit 3 will repeat some or all of visit
1.