AVANT to Develop an Oral Anthrax and Plague Vaccine for U.S. Department of Defense.

Business Editors & Health/Medical Writers

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NEEDHAM, Mass.--(BUSINESS WIRE)--Jan. 22, 2003

AVANT Immunotherapeutics, Inc. (Nasdaq: AVAN) today announced it has been awarded a subcontract to develop for the U.S. Department of Defense an oral combination vaccine against anthrax and plague using AVANT's proprietary vaccine technologies. Under the agreement, AVANT may receive in excess of $8 million over a two-year period, covering vaccine development through preclinical testing. AVANT executed the subcontract with DynPort Vaccine Company LLC ("DVC"), the prime contractor for the Defense Department's Joint Vaccine Acquisition Program (JVAP). Headquartered in Fort Detrick, MD, JVAP is the lead Defense Department organization for the development and purchase of vaccines for the U.S. military.

"This contract represents one of the first awards from a major U.S. Department of Defense (DoD) initiative to apply modern biotechnological innovations to the development of vaccines that can offer rapid, effective protection from multiple biological agents," said Una S. Ryan, Ph.D., President and Chief Executive Officer of AVANT Immunotherapeutics, Inc. "Current vaccines against bacterial bioweapons like anthrax (Bacillus anthracis) and plague (Yersinia pestis) require a protracted dosing regimen or provide only limited protection, and each vaccine protects against only a single agent. The Defense Department is looking for new, improved generation vaccines that are effective, single-dose, and can protect against multiple agents. The choice of AVANT to conduct this development program is an important recognition of the strength of AVANT's vaccine and vector technologies for accomplishing these aims."

"This contract is very important to AVANT since it provides non-dilutive funding to the company and it means that AVANT now has over two years of cash and cash equivalents on hand," Dr. Ryan concluded.

Senator Edward M. Kennedy (D-MA), Ranking Democrat of the Senate Committee on Health and a senior member of the Senate Armed Services Committee, stated, "I am very pleased that the Defense Department has chosen AVANT, a leading Massachusetts biotechnology firm, to conduct this pioneering effort in the development of a next-generation biodefense vaccine. The anthrax attacks of 2001 were a tragic reminder of the need for modern vaccines to protect our men and women in uniform as well as the public at large. I commend DoD's efforts in this area, and I look forward to yet another successful application of AVANT's vaccine technology to meeting this vital national security and healthcare challenge."

Senator John Kerry (D-MA), Ranking Member of the Senate Committee on Small Business, stated, "AVANT's success in this area is proof that America's small businesses can play a vital role in protecting our fighting men and women from biological weapons. Small business offers the innovation and flexibility our forces need to defeat novel threats that are constantly changing. As we contemplate sending our forces into battle where they could face biological weapons, it is reassuring to see that the Defense Department is moving ahead to acquire the most effective means of safeguarding them."

Dr. Ryan commended Senator Kennedy and Senator Kerry for their support of the JVAP program funding biodefense vaccine development: "Without support from enlightened legislators like Senator Kennedy and Senator Kerry, the development of required advanced-technology vaccines would continue to lag behind the threats our nation faces.

We are grateful for their leadership in making this program possible."

DVC is currently developing seven vaccines for the Department of Defense Joint Vaccine Acquisition Program and is the first company to initiate clinical trials on the new smallpox vaccine for the Department of Defense. They are also expected to be the first to complete the trials for vaccinia immune globulin (VIG), an antiserum needed for the smallpox vaccination program. DVC's mission is to develop vaccines that meet the highest standards and requirements for today's soldiers. "Vaccination of a large number of individuals would be facilitated if an orally administered vaccine were available," said Terry Irgens, RPh, President of DVC. "AVANT's concept that several vaccines could be delivered simultaneously would be state-of-the-art. We look forward to investigating this technology as an alternative to an injectable vaccine."

Under the subcontract, AVANT will develop a rapid-acting oral anthrax and plague vaccine based on the company's modified live vaccine technology. This technology will use genetically modified bacteria as vectors, or "buses," to deliver plague and anthrax antigens to the immune system in a way that quickly stimulates protective immunity against these microbes - both of which have potential for use as bioweapons. AVANT expects to conduct the vaccine research at both its Needham, Massachusetts and St. Louis, Missouri laboratories.

The proposed vaccine will offer dramatic advances over current-generation biodefense vaccines. For example, the current generation anthrax vaccine administered to U.S. troops requires individuals to undergo a series of six injections over an 18-month period. This vaccine confers immunity to anthrax gradually, over a number of weeks. Recipients of this vaccine have complained of considerable muscular soreness in reaction to the injections. By contrast, the proposed anthrax-plague vaccine to be developed by AVANT is designed to have the attributes of AVANT's travelers' vaccines against cholera and typhoid fever--require a single oral dose, confer immunity within days, and cause minimal side effects.

Scientists at AVANT created the vectoring technology as part of the company's development of orally administered bacterial vaccine candidates against cholera (Vibrio cholerae, Peru-15) and typhoid fever (Salmonella typhi, Ty800). Peru-15 and Ty800 were created using genetic techniques to delete genes known to be essential to the virulence of the parent microorganism. As a result of these alterations, AVANT's vaccine candidates have been shown in the clinic to be well tolerated by humans. Moreover, results of a Phase IIb challenge study with AVANT's Peru-15 cholera vaccine candidate demonstrated the ability of a single dose of that vaccine to protect subjects against moderate or severe diarrhea following administration of live Vibrio cholerae bacteria. This study was conducted under the sponsorship of the National Institute of Allergy and Infectious Disease (NIAID) of the National Institutes of Health (NIH) in collaboration with the Walter Reed Army Institute of Research (WRAIR)

About DVC

DVC, a joint venture between DynCorp of Reston, Virginia and Porton International, Inc., is chartered with providing an integrated approach for the advanced development of specific vaccines and other products to protect against the threat of biological warfare agents. In 1997, the U.S. Department of Defense initiated the Joint Vaccine Acquisition Program, which includes a 10-year contract with DVC for the development of vaccines against certain acute infectious diseases and contagious diseases.

About AVANT

AVANT Immunotherapeutics, Inc. is engaged in the discovery, development and commercialization of products that harness the human immune system to prevent and treat disease. The company is developing a broad portfolio of vaccines against viral and bacterial diseases, including single-dose oral vaccines aimed at protecting travelers from cholera, typhoid fever and other illnesses. In addition, the company is conducting clinical studies of a proprietary vaccine candidate for cholesterol management. AVANT further leverages the value of its technology portfolio through corporate partnerships. Current collaborations encompass the development of an oral human rotavirus vaccine, vaccines to combat threats of biological warfare, and vaccines addressed to human food safety and animal health.

Additional information on AVANT Immunotherapeutics, Inc. can be obtained through our site on the World Wide Web: http://www.avantimmune.com.

Safe Harbor Statement Under the Private Securities Litigation Reform Act of 1995: This release includes forward-looking statements which reflect AVANT's current views with respect to future events and financial performance. These forward-looking statements are based on management's beliefs and assumptions and information currently available. The words "believe," "expect," "anticipate," "intend," "estimate," "project" and similar expressions which do not relate solely to historical matters identify forward-looking statements. Investors should be cautious in relying on forward-looking statements because they are subject to a variety of risks, uncertainties, and other factors that could cause actual results to differ materially from those expressed in any such forward-looking statements. These factors include, but are not limited to: (1) the proposed acquisition of UPT and related transactions may not be consummated on the terms currently anticipated or at all; (2) the ability to adapt AVANT's vectoring systems to develop new, safe and effective orally administered vaccines against anthrax and plague or any other microbes used as bioweapons; (3) the ability to successfully complete development and commercialization of CholeraGarde(TM) (Peru-15), Ty800 and of other products; (4) the cost, timing, scope and results of ongoing safety and efficacy trials of CholeraGarde(TM) (Peru-15), Ty800 and other preclinical and clinical testing; (5) the ability to successfully complete product research and further development, including animal, pre-clinical and clinical studies of CholeraGarde(TM) (Peru-15), Ty800 and other products; (6) the ability of the Company to manage multiple late stage clinical trials for a variety of product candidates; (7) the volume and profitability of product sales of Megan(R)Vac 1 and other future products; (8) changes in existing and potential relationships with corporate collaborators; (9) the cost, delivery and quality of clinical and commercial grade materials supplied by contract manufacturers (10) the timing, cost and uncertainty of obtaining regulatory approvals to use CholeraGarde(TM) (Peru-15) and Ty800, among other purposes, to protect travelers and people in endemic regions from diarrhea causing diseases and for other products; (11) the ability to obtain substantial additional funding; (12) the ability to develop and commercialize products before competitors; (13) the ability to retain certain members of management; and (14) other factors detailed from time to time in filings with the Securities and Exchange Commission. We expressly disclaim any responsibility to update forward-looking statements.