OP0318 RATIONALE AND STUDY DESIGN FOR A PHASE 2, DOUBLE-BLINDED, RANDOMIZED, DOSE-REPEATING, CROSS-OVER STUDY TO ASSESS SAFETY AND EFFICACY OF ALLOGENEIC UMBILICAL CORD LINING STEM CELLS ON DISEASE SEVERITY AND STEROID TAPERING IN PARTICIPANTS WITH IDIOPATHIC INFLAMMATORY MYOPATHY | Publicación