XOMA announced that the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, has informed the Company that it is initiating a Phase 1 clinical trial for XOMA 3AB, XOMA’s novel formulation of three antibodies designed to prevent and treat botulism poisoning, among the most deadly bioterror threats

BERKELEY, CA, USA | May 3, 2011 | XOMA Ltd. (Nasdaq:XOMA – News), a leader in the discovery and development of therapeutic antibodies, today announced that the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, has informed the Company that it is initiating a Phase 1 clinical trial for XOMA 3AB, XOMA’s novel formulation of three antibodies designed to prevent and treat botulism poisoning, among the most deadly bioterror threats.

The Phase 1 trial is a double-blind, dose escalation study of a single administration of XOMA 3AB or placebo in approximately 24 healthy volunteers, to be conducted at Johns Hopkins University (Baltimore, MD) under an investigational new drug application filed by NIAID with the Food and Drug Administration. The objectives of the study are to assess safety and tolerability and determine the pharmacokinetic profile of XOMA 3AB.

"Initiation of testing of XOMA 3AB in humans is a very important milestone towards the development of this treatment against serious illness caused by the botulinum neurotoxin. We will be working closely with NIAID and other government agencies, including FDA, to further support its advancement," said Patrick J. Scannon, M.D., Ph.D., XOMA’s Executive Vice President and Chief Scientific Officer. "If successful, XOMA 3AB could ultimately be a candidate for addition to the U.S. government’s Strategic National Stockpile of medical countermeasures available in the event of natural or man-made public health emergencies."

The XOMA 3AB program is based on more than a decade of breakthrough biomedical research conducted in the laboratory of James Marks, M.D., Ph.D., Professor of Anesthesia at the University of California, San Francisco (UCSF), and on XOMA’s extensive antibody development expertise and platform technologies. The UCSF preclinical research program was funded by the National Institutes of Health and Department of Defense and identified lead antibody candidates which when combined led to highly potent toxin neutralization at very low doses. XOMA’s expertise enabled the development of the necessary techniques for ensuring the potency and stability of the three antibodies in XOMA 3AB under various conditions and the uniform pharmacokinetics of each antibody in the formulation. To date, XOMA has entered into nearly $100 million in U.S. government contracts for its botulism-related biodefense program.

Botulinum Neurotoxin

Botulism is a muscle-paralyzing disease caused by one of the most deadly known toxins, a neurotoxin made by the bacterium Clostridium botulinum. Exposure to the botulinum neurotoxin can cause muscle paralysis that can eventually lead to death. Botulism can be acquired through consumption of contaminated foods or through infection of a wound. Due to the risk posed by the botulinum neurotoxin as a biological weapon and the severity of disease, it has been classified by the U.S. government as a Category A bioterrorism agent.

The XOMA 3AB project has been funded in whole or in part with funds from the National Institute of Allergy and Infectious Diseases, National Institutes of Health, Department of Health and Human Services under Contract No. HHSN266200600008C, Contract No. HHSN272200800028C, Contract No. HHSN266200600011C and Contract No. HHSN272200800026C.

About XOMA

XOMA is a leader in the discovery and development of novel antibody therapeutics. The company’s proprietary product pipeline includes:

* XOMA 052, a potentially best-in-class antibody that binds to the inflammatory cytokine interleukin-1 beta, or IL-1 beta. XOMA plans to enter XOMA 052 into Phase 3 clinical development in Behcet’s uveitis, an orphan indication. XOMA 052 is in Phase 2 clinical development for diabetes with cardiovascular disease biomarkers. Les Laboratoires Servier is XOMA’s regional development and commercialization partner for XOMA 052.
* XOMA 3AB, a novel triple-antibody product candidate under development to prevent and treat botulism poisoning caused by exposure to botulinum neurotoxin Type A, among the most deadly bioterror threats. XOMA 3AB is under development through funding provided by the National Institute of Allergy and Infectious Diseases of the National Institutes of Health.
* A preclinical pipeline with candidates in development for autoimmune, cardio-metabolic, inflammatory, ophthalmic and oncologic diseases.

XOMA has a premier antibody discovery and development platform that incorporates an unmatched collection of antibody phage display libraries and proprietary expression and manufacturing technologies that it uses for its own pipeline and in license and collaboration agreements with pharmaceutical and biotechnology companies. XOMA technologies have contributed to the success of marketed antibody products including LUCENTIS(R) for wet age-related macular degeneration and CIMZIA(R) for rheumatoid arthritis and Crohn’s disease. XOMA’s fully integrated product development infrastructure extends from preclinical science to approval and is located in Berkeley, California. For more information, please visit www.xoma.com.

SOURCE: XOMA Ltd.