The purpose of this study is to evaluate the safety and tolerability of visilizumab in patients with severe ulcerative colitis that has failed to respond to steroid therapy.

What is visilizumab?

Visilizumab is an antibody designed to reduce inflammation. Antibodies are proteins that are normally made by the immune system to help defend the body from infections and other foreign substances. Visilizumab is thought to selectively affect the immune system to decrease inflammation and, in doing so, it may prevent damage to the intestine caused by ulcerative colitis.

Who can participate in this study?

The target population for this study is adults with severe ulcerative colitis that has resisted intravenous (IV) steroids. This study is open to patients with the following characteristics:

• 16-70 year olds
• A diagnosis of ulcerative colitis verified by colonoscopy or barium enema performed within 36 months prior to study entry
• Active disease despite ongoing treatment with steroids

How is this study conducted?

Eligible participants will be administered visilizumab as one daily injection on two consecutive days. All medication and study-related care, except for the costs of in-patient hospitalization, are provided to qualified participants at no cost. This includes all visits, examinations and laboratory work.

How does one get more information?

This study is currently enrolling patients at hospitals and clinics in North America and Europe. For more information on the study or how to participate in it, please call 1-800-772-0482, email InfoCenter@pdl.com or visit www.IBDtrials.com.

PDL BioPharma, Inc. was formerly known as Protein Design Labs, Inc.

Inclusion Criteria:

• 16 -70 year olds
• A diagnosis of ulcerative colitis verified by colonoscopy or barium enema performed within 36 months prior to study entry
• Active disease despite ongoing treatment with IV steroids