Orphan designation: 2-[3-(2-chloro-4-{[5-cyclopropyl-3-(2,6-dichlorophenyl)-1,2-oxazol-4-yl]methoxy}phenyl)-3-hydroxyazetidin-1-yl]pyridine-4-carboxylic acid-2-amino-2-(hydroxymethyl)propane-1,3-diol (1/1), Treatment of primary sclerosing cholangitis