Project participation inclusion criteria

1. Parents or legal guardians of project participants must express a written informed consent prior to performing any study related procedures, and if patients are over 13 years old, they also have to do it themselves.

2. Declared readiness to follow all the research procedures and availability for the duration of the project.

3. Boys aged ≥ 8 years and < 19 years at the moment of entering the study (from reaching the age of 8 years until the last day before the 19th birthday).

4. An ability to take pills and willingness to follow the intervention schedule in the study.

5. The patient with confirmed DMD; a clinical picture consistent with typical DMD and:

• A muscle biopsy – dystrophin immunofluorescence and/ or immunoblot analyses showing the complete absence of dystrophin or
• an identifiable mutation within the DMD gene (deletion/duplication of one or more exons), where the reading frame can be predicted as an “out-of-frame” or 
• Complete dystrophin gene sequencing showing an alteration (point mutation, duplication, others) that is expected to preclude the production of dystrophin protein (i.e. nonsense mutation, deletion/duplication leading to a further stop codon).

6. Taking drugs from the ACE inhibitor or ARB group in the minimum required doses for at least 30 days prior to the enrollment in the study.

Project participation exclusion criteria:

1. A current or previous regular use of any drugs from the beta group blockers.

2. Participating in any other clinical trial of new DMD therapies.

3. Clinically significant bradycardia at rest or by Holter ECG, based on age and sex adjusted normal values, the atrioventricular block higher than the first degree at rest and the Wenckebach second degree AV block at night, breaks longer than 2.5 sec.

4. The presence of a pacemaker or an ICD.

5. Heart failure symptoms.

6. Left ventricular ejection fraction (LVEF) < 57% (assessed by echocardiography using Teichholz formula).

7. A failure to obtain the appropriate quality of echocardiography images (necessary for monitoring the primary efficacy endpoint and safety).

8. Known allergic reactions to any of the components of the investigational medicinal product (Investigational Medicinal Product – IMP).

If the patient meets all the inclusion criteria other than taking ACE inhibitors or ARBs, please, contact our center. On the basis of the telephone conversation, the further strategy will be presented to you.

We encourage you to fill out the project application form even if you have doubts. Our doctors will contact you after the preliminary analysis of the information and present the possibilities of the patient’s participation in the project.