The T-cell inhibitor efalizumab (Raptiva) has demonstrated efficacy in the treatment of moderate to severe plaque psoriasis. However, it has not demonstrated efficacy for the treatment of psoriatic arthritis and, in one study, was associated with worsening of arthritis symptoms.

Excerpt from:
New Onset Psoriatic Arthritis Reported in Psoriasis Patients Treated with Efalizumab