A method which comprises identifying the presence, absence or amount of a biomarker in a subject having an inflammatory myopathy to whom an immunosuppressive drug has been administered, wherein the biomarker is a microRNA-133 selected from one or more of the group consisting of microRNA-133a-1, microRNA-133a-2 and mircroRNA-133b and maintaining a subsequent dosage of the drug or adjusting a subsequent dosage of the drug administered to the subject based on the presence, absence or amount of the biomarker identified in the subject.
