In the Medical Letter article on ustekinumab (Stelara) for psoriasis (2010; 52:7), footnote 2 in table 2 should have included a second sentence: $5595.60 is the cost of one 45-mg syringe.

The FDA has approved the use of ustekinumab (Stelara - Centocor Ortho Biotech), an interleukin antagonist given by subcutaneous (SC) injection for treatment of adults with moderate to severe plaque psoriasis. It is the first agent in its class for this indication; the other biologic agents for psoriasis are Tcell or tumor necrosis factor (TNF) inhibitors.

The pathogenesis of acne is multifactorial: follicular hyperkeratinization, Propionibacterium acnes bacteria, sebum production, androgens and inflammation have all been implicated. P. acnes, a gram-positive microaerophilic bacterium, plays an important role in the development of acne lesions by secreting chemotactic factors that attract leukocytes to the follicle, causing inflammation.

Efalizumab (Raptiva - Genentech/XOMA), a humanized monoclonal antibody that inhibits T-cell activation, has been approved by the FDA for treatment of adults with moderate to severe chronic plaque psoriasis.

Alefacept (a le' fa sept; Amevive - Biogen) has been approved by the FDA for parenteral treatment of adults with moderate to severe chronic plaque psoriasis.