Respiratory Muscle Training in L-Onset Pompe Disease (LOPD)

Study Overview
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Brief Summary
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This study is being done to test the effects of respiratory muscle training (RMT) in patients with late-onset Pompe Disease (LOPD) who have weakness of their breathing muscles. The results of this study will help design future research studies about RMT in LOPD. The goals of this study are to decide if sham-RMT is a useful control condition for RMT and to choose the best ways to measure the health benefits of RMT in LOPD.

Official Title
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Respiratory Muscle Training in Late-Onset Pompe Disease

Conditions
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Glycogen Storage Disease Type II

Intervention / Treatment
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* Device: RMT therapy using modified RMT device
* Device: Sham-RMT therapy using modified RMT device


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥ 18 years Diagnosis of LOPD On enzyme replacement therapy for ≥ 26 weeks at pretest Able to follow directions for study participation Able to complete a home-based RMT regimen Exclusion Criteria: Neurodegenerative conditions (e.g. stroke, dementia) or other serious neurologic condition that would prevent meaningful study participation as determined at the discretion of the principle investigator Inability to give legally effective consent Inability to read and understand English

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

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: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Respiratory muscle training (RMT)<br>Subjects in the experimental arm will be given an inspiratory and expiratory RMT device to use during Duke-based and home-based RMT therapy. | Device: RMT therapy using modified RMT device<br>* The exercises provided by the RMT device is intended to strengthen breathing muscles.<br>|
| Sham Comparator: Sham-RMT<br>Subjects in control arm will be given an inspiratory and expiratory sham-device and will complete Duke-based and home-based sham-RMT therapy. | Device: Sham-RMT therapy using modified RMT device<br>* The exercises provided by the Sham-RMT modified device is not intended to strengthen breathing muscles.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in respiratory strength | RMT to sham-RMT comparison of maximum inspiratory pressures (MIP). Change pretest to posttest is primary measure (baseline to 12 weeks). | baseline, 12 weeks, 6 months, 9 months | 
| Feasibility of sham-RMT, as measured by program adherence | As measured by program adherence (good is considered greater than or equal to 80%). Helps determines if a future efficacy trial is warranted and if sham-RMT may be a good control condition for a future trial. | 12 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in maximum expiratory pressures (MEP) | Change pretest to posttest | baseline, 12 weeks, 6 months, 9 months | 
| Change in 6-minute walk test (6MWT) | Change pretest to posttest | baseline, 12 weeks, 6 months, 9 months | 
| Change in Gait, Stairs, Gower, and Chair (GSGC) scale | Change pretest to posttest | baseline, 12 weeks, 6 months, 9 months | 
| Change in peak cough flow (PCF) | Change pretest to posttest | baseline, 12 weeks, 6 months, 9 months | 
| Change in Rasch-built Pompe-specific Activity Score (R-PAct) | Change pretest to posttest | baseline, 12 weeks, 6 months, 9 months | 
| Change in diaphragm thickness | change pretest to posttest | baseline, 12 weeks, 6 months, 9 months |