Tacrolimus (FK 506)-A New Therapeutic Agent for Severe Recalcitrant Psoriasis

• Background.-Psoriasis, a disease of unknown etiology, is in some patients severe, extremely debilitating, and unre-sponsive to conventional therapies, including UV-B, oral psoralen with long-wave UV radiation in the A range (PUVA), oral retinoids, and methotrexate. We report the results from our study of seven patients with refractory psoriasis who were treated with the new immunosuppressive drug, tacroll-mus (FK 506). Observstions.-AII seven patients showed a dramatic resolution of psoriasis that remained in remission as long as they received full-dose therapy. Serial skin biopsy speci-mens demonstrated a rapid disappearance of the inflamma-tory infiltrate and a slower resolution of the epidermal changes. Tacrolimus was well tolerated during the 5.5 to 14 months of observation. Side effects, including nephrotoxic