AVANT Announces Vaccine Adjuvant Licenses with 3M

Celldex Therapeutics, Inc. (a wholly-owned subsidiary of AVANT Immunotherapeutics, Nasdaq: AVAN) today announced multi-year clinical research collaborations with the 3M to access their proprietary Immune Response Modifier Resiquimod™ (and additional Toll-Like Receptor 7/8 agonists (TLR)) for clinical study with Celldex’s proprietary Antigen Presenting Cell (APC) Targeting Technology™, for use as vaccine adjuvants. "The combination of 3M’s TLR 7/8 agonists with the APC Targeting TechnologyTM products is synergistic in itself, and we believe that they can also be used to create second generation conjugated vaccines that deliver the vaccine and TLR agonists directly to the immune system within a single construct,” said Tibor Keler, Ph.D., Chief Scientific Officer of AVANT Immunotherapeutics. "This collaboration, in addition to our existing agreement with Oncovir, allows us to conduct combination studies with clinically tested TLR agonists. We are now in a position to explore a comprehensive vaccine strategy that targets multiple individual immune activation pathways based on the most recent scientific advances.” The foundation of the APC Targeting TechnologyTM is the ability of the Company’s proprietary monoclonal antibodies to deliver vaccines directly to professional APCs, such as dendritic cells and macrophages. Celldex’s APC Targeting TechnologyTM product candidates can access the immune system far more efficiently than traditional vaccine approaches, and can be readily combined with adjuvants to enhance immunity against cancer or infectious diseases. "We believe that our APC Targeting TechnologyTM and our collaborative relationship with 3M and Oncovir provide us with a unique opportunity to develop combination immunotherapies,” added Thomas Davis, M.D., AVANT’s Chief Medical Officer. "The preclinical data suggest that combinations will be more potent, and the immunotherapy field is eager to see these combination tested. Our ability to license such adjuvants for comprehensive immunotherapy could open a new era.” The 3M and Oncovir products will initially be combined with Celldex’s lead APC Targeting TechnologyTM program, CDX-1307, currently in phase I studies for patients with incurable breast, bladder, pancreatic, or colorectal cancer. Additional clinical programs combining APC Targeting TechnologyTM and TLR agonists are planned in oncology and infectious disease indications. Celldex will have the flexibility to use these TLR agonists, alone or in combination, in conjunction with its novel antibody-targeting platform. This will enable the Company to uniquely advance its broad immunotherapy portfolio across a range of disease indications. About 3M A recognized leader in research and development, 3M produces thousands of innovative products for dozens of diverse markets. 3M’s core strength is applying its more than 40 distinct technology platforms – often in combination – to a wide array of customer needs. With $24 billion in sales, 3M employs 75,000 people worldwide and has operations in more than 60 countries. About Oncovir Oncovir, Inc is a pharmaceutical corporation dedicated to the development of nucleic-acid-based clinical therapies for cancer, infectious, immune, and degenerative disorders. Based in Washington, DC, Oncovir has been investigating the use of Hiltonol (Poly ICLC) in a series of clinical studies toward brain cancer and smallpox virus. About AVANT Immunotherapeutics, Inc. AVANT Immunotherapeutics and Celldex Therapeutics combined during the first quarter of 2008. AVANT Immunotherapeutics, Inc. is a NASDAQ-listed company discovering and developing innovative vaccines and targeted immunotherapeutics for the treatment of cancer, infectious and inflammatory diseases. AVANT focuses on the use of tumor-specific targets and human monoclonal antibodies (mAbs) to precisely deliver therapeutic agents through its novel "targeted immunization” approach. In addition, AVANT is exploiting its access to proprietary human antibody technology for development of therapeutic monoclonal antibodies (mAbs). AVANT’s deep product pipeline consists of products in varying stages of development, with its lead candidate, CDX-110, partnered with Pfizer, Inc., currently undergoing evaluation in a Phase 2b/3 clinical trial in newly diagnosed glioblastoma multiforme, one of the most aggressive forms of brain cancer. AVANT also has five product candidates in its development pipeline including: CDX-1307, a product based on its proprietary APC Targeting Technology™, which is in two Phase 1 clinical trials for patients with advanced pancreatic, bladder, breast and colon cancer; TP10, a complement inhibitor, in development for transplantation and other indications; and Three candidates based on its oral, rapidly-protecting, single-dose and temperature-stable vaccine technology, including combination vaccines for travelers, the military and global health needs. AVANT has three commercialized products, including Rotarix® for the prevention of rotavirus infection and two human food safety vaccines for reducing salmonella infection in chickens and eggs. Additional information on AVANT Immunotherapeutics, Inc. can be obtained through its 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 that are subject to a variety of risks and uncertainties and reflect AVANT’s current views with respect to future events and financial performance. There are a number of important factors that could cause the actual results to differ materially from those expressed in any forward-looking statement made by AVANT. These factors include, but are not limited to: (1) the successful integration of the businesses, multiple technologies and programs of AVANT and Celldex; (2) the ability to adopt AVANT’s APC Targeting TechnologyTM to develop new, safe and effective vaccines against oncology and infectious disease indications, as well as our ability to develop combination immunotherapies; (3) the ability to adapt AVANT’s vectoring systems to develop new, safe and effective orally administered vaccines against disease causing agents; (4) the ability to successfully complete product research and further development, including animal, pre-clinical and clinical studies, and commercialization of CDX-110, CDX-1307, CholeraGarde® (Peru-15), Ty800, ETEC E. coli vaccine, and other products and AVANT’s expectations regarding market growth; (5) the cost, timing, scope and results of ongoing safety and efficacy trials of CDX-110, CDX-1307, CholeraGarde® (Peru-15), Ty800, ETEC E. coli vaccine and other preclinical and clinical testing; (6) the ability to negotiate strategic partnerships or other disposition transactions for AVANT’s cardiovascular programs, including TP10 and CETi; (7) the ability of AVANT to manage multiple clinical trials for a variety of product candidates; (8) the volume and profitability of product sales of Megan®Vac 1, Megan®Egg and other future products; (9) the process of obtaining regulatory approval for the sale of Rotarix® in major commercial markets, as well as the timing and success of worldwide commercialization of Rotarix® by our partner, GlaxoSmithKline or Glaxo; (10) Glaxo’s strategy and business plans to launch and supply Rotarix® worldwide, including in the U.S. and other major markets and its payment of royalties to AVANT; (11) Pfizer’s and our strategy and business plans concerning the continued development and commercialization of CDX-110; (12) AVANT’s expectations regarding its technological capabilities and expanding its focus to broader markets for vaccines; (13) changes in existing and potential relationships with corporate collaborators; (14) the availability, cost, delivery and quality of clinical and commercial grade materials produced at AVANT’s own manufacturing facility or supplied by contract manufacturers and partners; (15) the timing, cost and uncertainty of obtaining regulatory approvals; (16) AVANT’s ability to develop and commercialize products before competitors that are superior to the alternatives developed by such competitors; (17) AVANT’s ability to retain certain members of management;(18) AVANT’s expectations regarding research and development expenses and general and administrative expenses; (19) AVANT’s expectations regarding cash balances, capital requirements, anticipated royalty payments (including those from Paul Royalty Fund), revenues and expenses, including infrastructure expenses; (20) the ability to obtain substantial additional funding; (21) AVANT’s belief regarding the validity of our patents and potential litigation; and (22) certain other factors that might cause AVANT’s actual results to differ materially from those in the forward-looking statements including those set forth under the headings "Business,” "Risk Factors” and Management’s Discussion and Analysis of Financial Condition and Results of Operations” in each of AVANT’s Annual Report on Form 10-K, its current Reports on Form 8-K, as well as those described in AVANT’s other press releases and filings with the Securities and Exchange Commission, from time to time. You should carefully review all of these factors, and you should be aware that there may be other factors that could cause these differences. These forward-looking statements were based on information, plans and estimates at the date of this press release, and AVANT does not promise to update any forward-looking statements to reflect changes in underlying assumptions or factors, new information, future events or other changes.