XOMA Announces Conference Call and Webcast On July 14 to Review Top Line Multi-dose...

XOMA Announces Conference Call and Webcast On July 14 to Review Top Line
Multi-dose and Other Results of Its Phase 1 Clinical Trial of XOMA 052 in Type 2
Diabetes

BERKELEY, Calif., July 7, 2009 (GLOBE NEWSWIRE) -- XOMA Ltd. (Nasdaq:XOMA), a
leader in the discovery and development of therapeutic antibodies, announced
plans to hold a conference call and webcast on July 14, 2009 at 4:30 pm Eastern
time to discuss top line results from its randomized, placebo-controlled U.S.
Phase 1 trial of XOMA 052 in Type 2 diabetes. Marc Y. Donath, M.D., a pioneer in
anti-inflammatory approaches to Type 2 diabetes, Professor at the University
Hospital of Zurich and XOMA 052 European clinical trial principal investigator,
will participate on the call with XOMA management.

The conference call and webcast will follow the release of the XOMA 052 Phase 1
results shortly after the close of the U.S. financial markets that day. The
webcast can be accessed via XOMA's website at
http://investors.xoma.com/events.cfm and will be available for audio and slide
replay until close of business on October 14, 2009. Telephone numbers for the
live audio cast are 888-523-1245 (U.S./Canada) and 719-457-2734 (international).
A telephonic replay will be available beginning approximately two hours after
the conclusion of the call until close of business on July 21, 2009. Telephone
numbers for the replay are 888-203-1112 (U.S./Canada) and 719-457-0820
(international), passcode # 3435934.

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 IL-1 beta, a pro-inflammatory cytokine involved in the
development of Type 2 diabetes, cardiovascular disease, rheumatoid arthritis,
gout and other diseases. 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 052 has a half-life of 22 days. Based on
its binding properties, specificity to IL-1 beta and half-life, XOMA 052 may
provide convenient dosing of once per month or less frequently.

XOMA developed XOMA 052 using the company's proprietary antibody technologies,
capabilities and expertise. XOMA owns worldwide rights to the antibody and
related intellectual property. The company is actively pursuing a partnership
for the development and commercialization of XOMA 052.

About XOMA

XOMA discovers, develops and manufactures antibody therapeutics designed to
treat inflammatory, autoimmune, infectious and cancerous diseases. The company's
proprietary product pipeline includes XOMA 052, an anti-IL-1 beta antibody, and
XOMA 3AB, a biodefense anti-botulism antibody candidate.

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 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 leading antibody phage display libraries and XOMA's proprietary
Human Engineering(tm) and Bacterial Cell Expression and manufacturing
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 about 200 employees at its Berkeley location. For more
information, please visit http://www.xoma.com.

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

Forward-Looking Statements

Certain statements contained herein concerning 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 XOMA's ability to remain in compliance
with or renegotiate the requirements of its loan agreements; the declining and
generally unstable nature of current economic conditions; the results of
discovery 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 relationships; the
ability of collaborators and other partners 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.

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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