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Celldex Therapeutics Presents Positive Clinical Data from Phase 1 Studies of Antibody-Based Cancer Vaccine Candidate, CDX-1307

--Data presented at iSBTc meeting; Phase 2 initiation in first quarter 2010--

NEEDHAM, Mass.--(BUSINESS WIRE)--Oct 29, 2009 - Celldex Therapeutics, Inc. (NASDAQ: CLDX) today announced positive results from Phase 1 studies of CDX-1307 in patients with advanced epithelial cancers, including breast, colon, bladder and pancreatic cancer. CDX-1307, the first candidate from the Company's Precision Targeted Immunotherapy Platform, utilizes monoclonal antibodies to deliver vaccine directly to the patient's immune system and focuses the immune system against hCG beta (hCG-β), a cancer-associated target believed to play a role in more aggressive forms of the disease. The data, presented at the 24th Annual Meeting of the International Society for Biological Therapy of Cancer (iSBTc) in Washington, D.C., demonstrated enhanced immunological and biological responses and support the planned initiation of Phase 2 clinical trials in hCG-β expressing cancers.

The Phase 1 studies investigated the safety and immunogenicity of CDX-1307 alone and in combination with adjuvants, including GM-CSF and Toll-like Receptor (TLR) agonists (poly-ICLC or Hiltonol™ and R848 or resiquimod). The studies enrolled more than 80 patients with heavily pretreated, advanced-stage breast, colon, bladder and pancreatic cancer, with an average of 4.6 prior therapies across the treatment population. All patient cohorts demonstrated a favorable safety profile with no dose limiting toxicity to date. The combination of CDX-1307 with TLR agonists significantly enhanced immune responses against hCG-β, providing strong humoral responses in 88% of patients and cellular immune responses in 57% of patients analyzed to date. Immune responses occurred even in the presence of high circulating levels of hCG-β, suggesting that the CDX-1307 can overcome antigen tolerance in advanced and heavily pretreated cancers. Nine patients in the studies experienced disease stabilization from 2.3 months to 11.4 months following the initiation of CDX-1307 vaccination. Two of these patients have received multiple courses of CDX-1307 and continue treatment with stable disease at 6.4 and 11.4 months. These data provide the basis for advancing CDX-1307 into a front-line patient population selected for hCG-β expressing cancers. Celldex is planning the initiation of a Phase 2 study in patients with newly diagnosed bladder cancer in the first quarter of 2010.

“We have developed a CDX-1307 combination regimen that has shown promising results eliciting immunogenic and biologic responses in patients with advanced, difficult to treat and heavily pretreated cancers,” said Thomas Davis, M.D., Senior Vice President and Chief Medical Officer of Celldex Therapeutics. “Based on these findings, we will focus our efforts on CDX-1307 in earlier stage cancers where hCG-β appears to play an important role and where immunotherapy is likely to be even more effective, beginning with the initiation of a Phase 2 study in early-stage bladder cancer. Bladder cancer frequently expresses hCG-β and represents a clear unmet medical need—which we believe provides an excellent opportunity for CDX-1307.”


About CDX-1307


CDX-1307 is in early-stage development for the treatment of epithelial cancers that express the beta chain of human chorionic gonadotropin, known as hCG-β. hCG-β is a tumor associated antigen that is often linked to more aggressive disease and poor patient outcome. CDX-1307 is a fusion protein composed of a mannose receptor-specific human monoclonal antibody genetically fused with the hCG-β antigen. This antibody-vaccine is designed to deliver hCG-β directly to the patient's immune system via the antibody which attaches to dendritic cells and induce strong hCG-β specific immune responses. This antibody delivery approach contrasts with earlier generation vaccines that required dendritic cells to find and ingest vaccines.


About Celldex Therapeutics, Inc.


Celldex Therapeutics is an integrated biopharmaceutical company that applies its comprehensive Precision Targeted Immunotherapy Platform to generate a pipeline of candidates to treat cancer and other difficult-to-treat diseases. Celldex's immunotherapy platform includes a complementary portfolio of monoclonal antibodies, antibody-targeted vaccines and immunomodulators to create novel disease-specific drug candidates. For more information, please visit


Safe Harbor Statement Under the Private Securities Litigation Reform Act of 1995: This release containsforward-looking statements” made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995, including those related to the Company's strategic focus and the future development and commercialization of CDX-1307 and our other programs. Forward-looking statements reflect management's current knowledge, assumptions, judgment and expectations regarding future performance or events. Although management believes that the expectations reflected in such statements are reasonable, they give no assurance that such expectations will prove to be correct and you should be aware that actual results could differ materially from those contained in the forward-looking statements. Forward-looking statements are subject to a number of risks and uncertainties, including, but not limited to, the successful integration of the businesses, multiple technologies and programs of CuraGen and Celldex; our ability to adapt APC Targeting TechnologyTM to develop new, safe and effective vaccines against oncology and infectious disease indications; our ability to successfully complete product research and further development of our programs; the uncertainties inherent in clinical testing; our ability to manage research and development efforts for multiple products at varying stages of development; Pfizer's and our strategy and business plans concerning the continued development and commercialization of CDX-110; the timing, cost and uncertainty of obtaining regulatory approvals; the failure of the market for the Company's programs to continue to develop; the inability to obtain additional capital; the inability to protect the Company's intellectual property; the loss of any executive officers or key personnel or consultants; competition; changes in the regulatory landscape or the imposition of regulations that affect the Company's products; and other risks detailed from time to time in the Company's filings with the Securities and Exchange Commission, including the Company's Form 10-K for the fiscal year ended December 31, 2008, and its Forms 10-Q and 8-K.




Contact: Celldex Therapeutics, Inc.

Anthony S. Marucci, 781-433-0771

President and CEO


Celldex Therapeutics, Inc.

Avery W. Catlin, 781-433-0771

Chief Financial Officer


For Media:

BMC Communications Group

Matthew Driscoll, 212-477-9007 x20



Posted: October 2009