XOMA to Announce 2010 First Quarter Financial Results and Host Webcast Conference Call on May 6

BERKELEY, Calif., April 29, 2010 (GLOBE NEWSWIRE) -- XOMA Ltd. (Nasdaq:XOMA), a leader in the discovery and development of antibody therapeutics, announced that the company will host a webcast conference call on Thursday, May 6, 2010 at 4:30 pm Eastern time to discuss 2010 first quarter financial results and provide a general business update.

The webcast conference call will follow the release of the company's first quarter 2010 financial results earlier that day. The webcast can be accessed via the Investors section of XOMA's website at http://investors.xoma.com/events.cfm and will be available for replay until close of business on July 6, 2010.

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, Type 1 diabetes and cardiovascular disease, 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, 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 200 employees at its Berkeley, California location. For more information, please visit http://www.xoma.com.

The XOMA Ltd. logo is available at https://www.globenewswire.com/newsroom/prs/?pkgid=5960

Safe Harbor Statement

Certain statements contained herein relating to the anticipated closing of the offering or product development, 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 the results of discovery research and preclinical 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); uncertainties regarding the status of biotechnology patents; uncertainties as to the cost of protecting intellectual property; changes in the status of the existing collaborative and licensing relationships; the ability of collaborators, licensees and other third parties to meet their obligations; market demand for products; scale up and marketing capabilities; competition; international operations; share price volatility; XOMA's financing needs and opportunities; and risks associated with XOMA's status as a Bermuda company, are described in more detail in XOMA's most recent annual report on Form 10-K and in other SEC filings. Consider such risks carefully in considering XOMA's prospects.

CONTACT:  XOMA Ltd.
          Company and Investor Contact:
          Carol DeGuzman
          510-204-7270
          deguzman@xoma.com

          Porter Novelli Life Sciences
          Media Contact:
          Carolyn Hawley
          619-849-5375
          chawley@pnlifesciences.com

Released April 29, 2010