VDR and psoriasis: Ointment containing 1,25-dihydroxy-22-oxavitamin D3 (maxacalcitol), a noncalcemic analog of the active form of vitamin D3, is used for the treatment of hyperkeratotic cutaneous conditions such as psoriasis, ichtyosis, and acne vulgaris [18] because it suppresses the proliferation and promotes the differentiation of keratinocytes through interaction with the vitamin D receptor [19, 20].