XOMA Appoints Steve Doberstein to Vice President of Research

BERKELEY, Calif., Oct. 28, 2008 (GLOBE NEWSWIRE) -- XOMA Ltd. (Nasdaq:XOMA), a leader in the discovery and development of therapeutic antibodies, today announced the appointment of Stephen K. Doberstein, Ph.D., to the position of Vice President of Research. In this position, Dr. Doberstein will be responsible for directing XOMA's preclinical drug candidates through the discovery and development process, where he will focus on antibody discovery and cell line development. He will also support the clinical development of XOMA's portfolio of drug candidates through his direction of non-clinical safety, translational medicine and pharmacokinetics or pharmacodynamics experiments.

"Steve brings extensive experience in antibody engineering and a fresh eye for innovation to our world-class research development organization," said Steven Engle, Chairman and CEO of XOMA. "We anticipate that his leadership will contribute to enhancing XOMA's scientific position in academic, business and investor communities. Additionally, his past roles in forming strategic alliances with large pharmaceutical partners give him a wealth of expertise to advance our collaborations and licensing business."

Dr. Doberstein has 15 years of experience in biotechnology research and development. Most recently, he was Vice President of Research at Five Prime Therapeutics, Inc., a protein and antibody discovery and development company. There he led a research and preclinical development organization of more than 70 people, established programs resulting in four strategic alliances with pharmaceutical partners, built a strong proprietary pipeline, and moved multiple product candidates from concept to pre-IND stages in diabetes, oncology, rheumatoid arthritis and osteoarthritis. Prior to his position at FivePrime, he served as Vice President of Research at Xencor, Inc., an antibody engineering and development company, where he was instrumental in advancing its protein platform technologies and preclinical product candidates.

Dr. Doberstein holds a Ph.D. in Biochemistry, Cell and Molecular Biology from Johns Hopkins University School of Medicine and completed his postdoctoral work at UC Berkeley. He began his career as an Engineer at DuPont after earning his B.S.Ch.E. degree in Chemical Engineering from the University of Delaware.

About XOMA

XOMA discovers, develops and manufactures therapeutic antibody and other agents designed to treat inflammatory, autoimmune, infectious and cancerous diseases and is engaged in more than 13 active development projects. The Company's expanding pipeline includes XOMA 052, an anti-IL-1 beta antibody, and XOMA 629, a synthetic antimicrobial 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, LUCENTIS(r) (ranibizumab injection) for wet age-related macular degeneration and CIMZIA(r) (certolizumab pegol) for Crohn's disease.

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 technologies. Bacterial cell expression 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 with 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 approval, and a team of 330 employees at its Berkeley location. For more information, please visit http://www.xoma.com.

Forward Looking Statements

Certain statements contained herein relating to 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.

          Greg Mann

          Porter Novelli Life Sciences
          Media & Investors Contact:
          Carolyn Hawley