Micellar paclitaxel improves severe psoriasis in a prospective phase II pilot study

Background: Taxanes (eg, paclitaxel) are chemotherapeutic agents that have antiproliferative, antiangiogenic, and antiinflammatory properties. Objective: We sought to explore the safety and efficacy of paclitaxel in individuals with severe psoriasis. Methods: An open-label, prospective, phase II pilot study was conducted at the National Institutes of Health Clinical Center, a federal government medical research facility, in Bethesda, Maryland. Twelve patients with severe psoriasis, as defined by a baseline Psoriasis Area and Severity Index (PASI) score of ≥ 20), were studied. Initially, patients received 6 intravenous infusions of micellar paclitaxel, 75 mg/m², at 4-week intervals (stage I). Later patients received 9 intravenous infusions of micellar paclitaxel at 2-week intervals (37.5 mg/m² for 3 doses followed by 50 mg/m² for six additional doses) (stage II). The primary end point was the percent change in the PASI from week 0 to week 24 in stage I and from week 0 to week 20 in stage II. Results: In stage I, all 5 patients improved (mean = 59.7% decrease in PASI, median = 59.6%, range: 40.3%-79.2%). Four of the 7 patients completed stage II and all of these patients improved (mean = 45.9% decrease in PASI, median = 45.0%, range: 14.6%-79.1%). Micellar paclitaxel was well tolerated by most patients. Conclusions: Micellar paclitaxel demonstrates therapeutic activity in patients with severe psoriasis.