This study will evaluate the safety and effectiveness of micellar paclitaxel for treating severe psoriasis. Paclitaxel in another formulation (Taxol) is approved by the Food and Drug Administration for use in patients with cancer. This drug can decrease growth of cancer cells and of new blood vessels.

Because patients with psoriasis have an increase in skin cell and blood vessel growth, paclitaxel may also improve their condition. The dose of drug used in this study is much lower than those used to treat cancer patients and is expected to cause relatively few side effects.

Patients 18 to 70 years of age with psoriasis lesions affecting at least 20% of their skin may be eligible for this study. Candidates will be screened with a history and physical examination, blood and urine tests, electrocardiogram, and possibly an exercise stress test.

Participants will receive six intravenous (through a vein) infusions of paclitaxel over a 6-month period. Each infusion will take about 2 hours.

Patients will stay in the clinic for observation for at least 1 hour before going home and will return to the clinic for follow-up examination and tests one week after each infusion. However, on weeks 0 and 8 visit will last for approximately 8 hours and will require a return to the clinic the following morning. Blood collection will be performed during the week 0 and 8 visits to determine how fast Micellar Paclitaxel is eliminated from your body.

Approximately 2 teaspoons of blood will be taken prior to the infusion, twice during the infusion, and eight times during the 22 hours following the infusion for a total of eleven samples. These return visits will last approximately 1-2 hours. Patients will have the following procedures:

1. A skin biopsy (removal of a small tissue sample for microscopic examination) will be done at the first visit (week 0) and again at weeks 6, 14 and 22. The area of the biopsy will be numbed with an anesthetic, and a small circle of skin about the width of a pencil eraser and half as deep will be cut and lifted away. Stitches will be placed and removed 1 to 2 weeks later.
2. A history and physical examination will be done at every visit. Patients will be interviewed about changes in their skin condition and about treatment side effects and will be examined by a nurse or physician.
3. Blood and urine samples will be collected at frequent intervals (nearly every visit) to test for side effects.
4. Photographs of the skin will be taken at the first visit and at several later visits to document changes in psoriasis.
5. A blood sample will be drawn for genetic testing to look for gene changes in people with psoriasis.
6. An electrocardiogram will be taken at the last visit. This will be done at week 24 and compared to the screening EKG.
7. Gonadal toxicity monitoring will be started with all patients entered into the protocol as of May 2001. Blood will be drawn to measure Inhibit A for females and Inhibit B for males at weeks 0, 6, 14, and 22.