NASDAQ Grants XOMA's Request for Continued Listing

BERKELEY, Calif., June 15, 2010 (GLOBE NEWSWIRE) -- XOMA Ltd. (Nasdaq:XOMA), a leader in the discovery and development of therapeutic antibodies, today announced that a NASDAQ Listing Qualifications Panel (the "Panel") has granted the company's request for an extension of time, as permitted under NASDAQ's Listing Rules, to comply with the $1.00 per share minimum bid price requirement for continued listing. In accordance with the Panel's decision, on or before September 13, 2010, the company must evidence a closing bid price of $1.00 or more for a minimum of ten consecutive trading days or its common shares will be subject to delisting from The NASDAQ Global Market. Under NASDAQ's rules, this date represents the maximum length of time that a Panel may grant to regain compliance.

The determination follows the company's hearing before the Panel on May 6, 2010, at which the Panel considered the company's plan to regain compliance with the minimum bid price requirement, including seeking shareholder approval of a potential reverse stock split at its 2010 annual general meeting of shareholders on July 21, 2010. The company is working diligently to satisfy the terms of the Panel's decision.

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 un-matched 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.

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

Forward-Looking Statements

Certain statements contained herein concerning the company's continued listing on NASDAQ 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:
          Carol DeGuzman
          510-204-7270
          deguzman@xoma.com

          Canale Communications
          Media Contact:
          Carolyn Hawley
          619-849-5375
          carolyn@canalecomm.com

Released June 15, 2010