XOMA announced the presentation of new preclinical results with XOMA 052 in the diet-induced obesity mouse model

BERKELEY, CA, USA | June 8, 2009 | XOMA Ltd. (Nasdaq:XOMA), a leader in the discovery and development of therapeutic antibodies, announced the presentation of new preclinical results with XOMA 052 in the diet-induced obesity mouse model. XOMA 052 addresses the inflammatory cause of Type 2 diabetes by targeting interleukin 1 beta (IL-1 beta), a master signaling protein which triggers inflammatory pathways. The results were presented at the American Diabetes Association (ADA) 69th Scientific Sessions in New Orleans, Louisiana.

"The diet-induced obesity model is a validated tool for evaluating the role of IL-1 in Type 2 diabetes that mimics the development of the disease in humans more closely than genetic or chemically-induced models," said Stephen K. Doberstein, Ph.D., XOMA’s Vice President of Research. "The data reported today clearly show the potential for XOMA 052 to improve glucose control, beta cell function and survival, and insulin resistance without contributing to weight gain. XOMA 052 also corrected the dyslipidemia associated this diabetes model, suggesting the potential for cardiovascular benefit."

Groups of mice received either a normal diet or a high fat/high sucrose diet and twice-weekly doses of XOMA 052 or an isotype control for 12 to 14 weeks. This study design enabled evaluation of XOMA 052 in both normal and simulated diabetic conditions. At the end of the study period, mice that received XOMA 052 and the high fat/high sucrose diet showed, as compared to control (mice receiving isotype control and on high fat/high sucrose diet), statistically significant:

* Reduction in glycosylated hemoglobin (HbA1c) levels
* Reduction in fasting blood glucose without causing hypoglycemia
* Improvement in glucose control
* Improvement in insulin secretion and beta cell function
* Protection from diet-induced beta cell apoptosis
* Increase in beta cell proliferation
* Reduction in total cholesterol without reduction in high
density lipoprotein
* Reduction in triglycerides and free fatty acids

The mice on the normal diet treated with XOMA 052 showed no significant changes as compared to control mice on the normal diet, including lack of additional weight gain.

The studies were conducted at University of Bremen (Germany) and at XOMA. The full ADA presentation (ADA abstract # 310-OR) will be available on the XOMA website, www.xoma.com.

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 interleukin-1 beta (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, the drug 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 has completed enrollment in Phase 1 trials for XOMA 052 in nearly 100 Type 2 diabetes patients and anticipates announcing top-line data from its U.S. trial in July. The trials were designed to evaluate a wide range of XOMA 052 doses, single and multiple dose regimens, and intravenous and subcutaneous routes of administration.

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 the Interleukin-1 Pathway

The central role of the IL-1 pathway in multiple diseases has been clinically validated by two FDA-approved therapies and several inhibitors of the inflammatory IL-1 pathway in clinical development. These disease indications include rheumatoid arthritis, systemic juvenile idiopathic arthritis, gout, Muckle-Wells syndrome, and others.

About XOMA

XOMA discovers, develops and manufactures therapeutic 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.

SOURCE: XOMA