Abstract Published on Initial Results From XOMA 052 Clinical Trial in Behcet's Disease

BERKELEY, Calif., May 12, 2010 (GLOBE NEWSWIRE) -- XOMA Ltd. (Nasdaq:XOMA), a leader in the discovery and development of therapeutic antibodies, announced the publication of an abstract titled, "Safe, Rapid-onset and Sustained Biological Activity of IL-1 beta Regulating Antibody XOMA 052 in Resistant Uveitis of Behcet's Disease: Preliminary Results of a Pilot Trial." Uveitis of Behcet's disease is an auto-inflammatory condition that can result in blindness or partial vision loss as described below. The abstract will be presented June 17, 2010 during the annual European Congress of Rheumatology in Rome, Italy by Professor Ahmet Gul, Istanbul Faculty of Medicine, Department of Internal Medicine, Division of Rheumatology, Istanbul University, Turkey, and principal investigator for this XOMA 052 clinical trial.

The abstract is available online at https://b-com.mci-group.com/Abstract/Statistics/AbstractStatisticsViewPage.aspx?AbstractID=19942&ItemsPerPage=20&AppliedFilter=[SubmitterFullName]%20Like%20'Ahmet%20%'&ShowOnlyInFinalAcceptance=true

Behcet's Disease and Uveitis

Behcet's (pronounced beh-CHETS) disease is a chronic auto-inflammatory disease that causes inflammation in blood vessels in the eye and elsewhere, and cankers or aphthous ulcers in the mouth and on the genitals. Symptoms may be acute and resolve in a few weeks or may persist chronically. The cause of the disease, for which there is no known cure, is unknown. Currently, important symptoms are treated with corticosteroids or with one or more immunosuppressive drugs, which can have serious side effects that can limit their effectiveness and duration of use.

Uveitis involves inflammation in the middle or back part of the eye (uvea), and occurs in about half of Behcet's disease patients. In patients who experience repeated eye inflammation, partial vision loss or blindness can result.

Behcet's disease was named after Professor Hulusi Behcet, a Turkish dermatologist who described the classic symptoms of the disease in 1937 as a distinct clinical entity. Behcet's disease is common in the Middle East, Asia and Japan, and rare in the U.S.

About XOMA 052

XOMA 052 is a potent monoclonal antibody with the potential to improve the treatment of patients with a wide variety of inflammatory diseases. XOMA 052 binds strongly to interleukin-1 beta (IL-1 beta), a pro-inflammatory cytokine involved in diseases including Type 2 diabetes, cardiovascular disease, rheumatoid arthritis, gout and auto-inflammatory diseases. IL-1 is a well-validated therapeutic target, with three marketed IL-1 inhibitors that have been used by more than 200,000 patients overall. By binding to IL-1 beta, XOMA 052 inhibits the activation of the IL-1 receptor, thereby preventing the cellular signaling events that produce inflammation.

XOMA is conducting two Phase 2 clinical trials of XOMA 052 in patients with Type 2 diabetes and a Phase 2 trial in Type 1 diabetes. The Phase 2 trials follow a successful 98 patient Phase 1 program in Type 2 diabetes patients in which XOMA 052 was shown to be well-tolerated, demonstrated evidence of biological activity in diabetes measures and cardiovascular biomarkers, and had a half-life that may provide convenient dosing of once per month or less frequently. The company has also demonstrated the potential for XOMA 052 in in vivo models of atherosclerosis and cardiac remodeling and in an in vitro model using human myeloma, or plasma cell cancer, cells.

About XOMA

XOMA discovers, develops and manufactures novel antibody therapeutics for its own proprietary pipeline as well as through license and collaborative agreements with pharmaceutical and biotechnology companies, and under its contracts with the U.S. government. The company's proprietary product pipeline includes:

  --  XOMA 052, an anti-IL-1 beta antibody in Phase 2 clinical development for
      Type 2 diabetes with cardiovascular biomarkers, Type 1 diabetes, and
      with potential for the treatment of a wide range of inflammatory
      conditions.

  --  XOMA 3AB, an antibody candidate in pre-IND studies to neutralize the
      botulinum toxin, among the most deadly potential bioterror threats,
      under development through funding provided by the National Institute of
      Allergy and Infectious Diseases of the National Institutes of Health
      (Contract # HHSN266200600008C).

  --  A preclinical pipeline with candidates in development for several
      diseases.

In addition to its proprietary pipeline, XOMA develops products with premier pharmaceutical companies including Novartis AG, Schering Corporation, a subsidiary of Merck & Co., Inc. and Takeda Pharmaceutical Company Limited.

XOMA's technologies have contributed to the success of marketed antibody products, including LUCENTIS(R) (ranibizumab injection) for wet age-related macular degeneration and CIMZIA(R) (certolizumab pegol) for rheumatoid arthritis and Crohn's disease.

The company has a premier antibody discovery and development platform that incorporates an unmatched collection of antibody phage display libraries and proprietary Human Engineering(TM), affinity maturation, Bacterial Cell Expression (BCE) and manufacturing technologies. BCE is a key breakthrough biotechnology for the discovery and manufacturing of antibodies and other proteins. As a result, more than 50 pharmaceutical and biotechnology companies have signed BCE licenses, and several licensed product candidates are in clinical development.

XOMA has a fully integrated product development infrastructure, extending from pre-clinical science to approval, and a team of about 215 employees at its Berkeley, California location. For more information, please visit http://www.xoma.com.

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Forward-Looking Statements

Certain statements contained herein concerning product development and capabilities of XOMA's technologies or that otherwise relate to future periods are forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. These statements are based on assumptions that may not prove accurate. Actual results could differ materially from those anticipated due to certain risks inherent in the biotechnology industry and for companies engaged in the development of new products in a regulated market.

These risks, including those related to inability to comply with NASDAQ's continued listing requirements; the generally unstable nature of current economic conditions; the results of discovery research and pre-clinical testing; the timing or results of pending and future clinical trials (including the design and progress of clinical trials; safety and efficacy of the products being tested; action, inaction or delay by the FDA, European or other regulators or their advisory bodies; and analysis or interpretation by, or submission to, these entities or others of scientific data); changes in the status of existing collaborative and licensing relationships; the ability of collaborators, licensees and other third parties to meet their obligations; XOMA's ability to meet the demands of the United States government agency with which it has entered into its government contracts; competition; market demands for products; scale-up and marketing capabilities; availability of additional licensing or collaboration opportunities; international operations; share price volatility; XOMA's financing needs and opportunities; uncertainties regarding the status of biotechnology patents; uncertainties as to the costs of protecting intellectual property; and risks associated with XOMA's status as a Bermuda company, are described in more detail in XOMA's most recent filing on Form 10-K and in other SEC filings. Consider such risks carefully when considering XOMA's prospects.

CONTACT:  XOMA Ltd.
          Company and Investor Contact:
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          deguzman@xoma.com

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