XOMA Appoints Mary L. Anderson as Vice President of Business Development

BERKELEY, Calif., March 10, 2008 (PRIME NEWSWIRE) -- XOMA Ltd. (Nasdaq:XOMA), a leader in the discovery and development of antibody therapeutics, today appointed Mary L. Anderson as Vice President of Business Development. Ms. Anderson will oversee XOMA's business development initiatives, including licensing activities related to XOMA's therapeutic pipeline, support of the antibody collaborations business, the licensing of the company's antibody technologies, and the advancement of biodefense programs.

"For over a decade, Mary has successfully driven multiple product and licensing deals from initiation through negotiation and completion," said Steven Engle, XOMA's Chairman and Chief Executive Officer. "During her recent experience at a large pharmaceutical company, she gained in-depth knowledge of the opportunities and deal-making environment that drive today's market. With her experience at a rapidly growing antibody discovery company, she is prepared to hit the ground running at XOMA as we work to expand our business development activities. We look forward to her contributions."

Ms. Anderson brings 20 years of experience in the pharmaceutical and biotechnology industry. Most recently, she served as the Executive Director, Global Licensing and Business Development for Oncology at Merck-Serono, a global biopharmaceuticals company with annual revenues of approximately $6 billion. At Merck-Serono she led the in-licensing of multiple clinical stage oncology products and was a key member of the team responsible for the approximately $15 billion acquisition of Serono SA.

Prior to joining Merck-Serono, Ms. Anderson was Senior Director, Corporate Development at MorphoSys, where she was charged with growing the antibody discovery business. She also held business development positions at Agensys and Bayer. Trained in biochemistry, Ms. Anderson spent her early years in research at Chiron and Gen-Probe. She received a Masters degree in business administration from St. Mary's College of California and a Bachelor of Science degree in biochemistry from California Polytechnic State University at San Luis Obispo.

About XOMA -- XOMA is a leader in the discovery, development and manufacture of therapeutic antibodies. The Company's expanding pipeline includes XOMA 052, an anti-IL-1 beta antibody, and XOMA 629, a synthetic peptide compound derived from bactericidal/permeability-increasing protein.

XOMA's proprietary development pipeline is primarily funded by multiple revenue streams resulting from the licensing of its antibody technologies, product royalties, development collaborations, and biodefense contracts. XOMA's technologies and experienced team have contributed to the success of marketed antibody products, including RAPTIVA(r) (efalizumab) for chronic moderate to severe plaque psoriasis and LUCENTIS(r) (ranibizumab injection) for wet age-related macular degeneration.

The Company has a premier antibody discovery and development platform that incorporates leading antibody phage display libraries and XOMA's proprietary Human Engineering(tm) and bacterial cell expression (BCE) 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.

In addition to developing its own products, XOMA develops products for premier pharmaceutical companies including Novartis AG, Schering-Plough Research Institute and Takeda Pharmaceutical Company Limited. XOMA has a fully integrated product development infrastructure, extending from pre-clinical science to product launch, and a team of 300 employees at its Berkeley location. For more information, please visit http://www.xoma.com.

Certain statements contained herein relating to product development and shareholder value, 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
          Company Contact:
          Greg Mann
          510-204-7270
          mann@xoma.com

          Porter Novelli Life Sciences
          Media & Investors Contact:
          Rachel Lipsitz
          619-849-5378
          rlipsitz@pnlifesciences.com

Released March 10, 2008