 - Used any of the following treatments within the indicated washout period before the baseline visit: 1 12 weeks or 5 half-lives whichever is longer - biologic agents eg, 24 weeks for alefacept, 12 weeks for etanercept, 15 weeks for ustekinumab; 2 12 weeks - oral retinoids eg, acitretin or isotretinoin; 3 8 weeks - cyclosporin, interferon, methotrexate, other systemic immunosuppressive or immunomodulating agents, or psoralen plus UVA light treatment; 4 4 weeks - systemic corticosteroids or adrenocorticotropic hormone analogs; 5 2 weeks - immunizations; drugs known to possibly worsen psoriasis, such as beta-blockers eg, propranolol, lithium, iodides, angiotensin-converting enzyme inhibitors, and indomethacin, unless on a stable dose for 12 weeks; 6 2 weeks - topical treatments: corticosteroids, immunomodulators, anthralin dithranol, Vitamin D derivatives, retinoids, or coal tar used on the body. 