Inclusion Criteria: * Confirmed diagnosis of LGMDR5 before age of 10, based on clinical presentation and genotyping * Ambulant male or female patients aged 6 to less than 12 years of age at screening * Able to perform the 10-meter walk test (10MWT) in less than 15 sec and to rise from chair with or without arm support Exclusion Criteria: * Detectable neutralizing antibodies against AAV8 * Cardiomyopathy with left ventricular ejection fraction (LVEF) \< 50% * Respiratory assistance * Concomitant medical condition that might interfere with LGMDR5 evolution * Acute illness within 4 weeks of anticipated IMP administration * Current participation in another clinical trial with investigational medicinal product * Previous participation in gene and cell therapy trials * Any condition that would contraindicate immunosuppressant treatment * Presence of any permanent items (e.g., metal braces) precluding undergoing MRI * Any vaccination 1 month prior to planned IMP administration * Serology consistent with HIV exposure or active hepatitis B or C infection * Grade 2 or higher lab abnormalities for liver function tests, creatinine, hemogram and coagulation