Tamoxifen in Duchenne Muscular Dystrophy

Exclusion Criteria

• •Known individual hypersensitivity or allergy to tamoxifen or other ingredients/excipients of IMP
• •Female gender
• •Use of tamoxifen or testosterone within the last 3 months
• •Known or suspected malignancy
• •Other chronic disease or clinically relevant limitation of renal, liver or heart function
• •Known or suspected non-compliance
• •Any injury which may impact functional testing, e.g. upper or lower limb fracture
• •Planned or expected spinal fusion surgery during the study period (as judged by the Investigator; i.e. due to rapid progressing scoliosis), previous spinal fusion surgery is allowed if it took place more than 6 months prior to screening.
• •Inability to follow the procedures of the study, e.g. due to language problems, psychological disorders of the participant/parents (as judged by the investigator)
• •Concomitant participation in any other interventional trial (and up to 3 months prior to screening)
• •Use of CYP2D6 inhibitors or of CYP3A4 inducers (apart from glucocorticoids), platelet aggregation inhibitors and coumarin-type anti-coagulants
• •Use of drugs metabolized by CYP2C9, such as phenprocoumon, phenytoin, warfarin, celecoxib, fluvastatin, ginko biloba, St. John's wort and sulfamethoxazol
• •Galactosemia (lack of galactose-1-phosphat-uridylyltransferase or UDP-galactose-4-epimerase or galactokinase; Fanconi-Bickel-syndrome); congenital lack of lactase; glucose-galactose malabsorption
• •Presence of one or more of the following eye disorders: cataract, retinopathia, optic neuropathy, alteration of the cornea
• •Presence of one or more of the following laboratory abnormalities: anaemia, thrombocytopenia, leukopenia, neutropenia or agranulocytosis
• •Group A:
• •Glucocorticoid naïve patients
• •Start of glucocorticoid treatment or change in dosage \<6 month prior to screening (dosing adaptations according to weight change are allowed)
• •Group B:
• •Glucocorticoid treated patients or patients that stopped glucocorticoid treatment \<6 month prior to screening
• •Assisted ventilation of any kind necessary