[An oral high dose formulation of calcitriol, the biologically active form of Vitamin D. Acting as a ligand for the Vitamin D receptor (VDR), DN-101 binds to the VDR inhibiting VDR-regulated gene transcription involved in cell proliferation, differentiation and apoptosis. (NCI) ( NCI )] (UMLS (NCI) C1328169) Ro 21-5535 =Organic Chemical; Pharmacologic Substance; Vitamin