CDX-110: Novel EGFRvIII Vaccine For Glioblastoma Multiforme

FDA has granted orphan drug designation for Celldex's CDX-110 for the treatment of EGFRvIII expressing Glioblastoma Multiforme (GBM).

GBM is the most common and aggressive form of brain cancer. CDX-110 is an immunotherapy that targets the tumor-specific growth promoter EGFRvIII. Celldex Therapeutics announced a definitive merger agreement with AVANT Immunotherapeutics, Inc. in October 2007.

In the ACTIVATE phase IIa study, CDX-110 treated GBM patients showed a median survival time of 30 months, more than a 100 percent increase in survival, versus the historical control's median of 14.5 months. The study has demonstrated a median time-to-progression of 13 months (p=0.0001) versus the historical control's median of 6.4 months. An extension study, ACT II, which combines CDX-110 with chemotherapy in a similar patient population, has not yet reached median time-to-progression or survival. However, preliminary progression free survival (PFS) and overall survival (OS) data in ACT II look very similar to the ACTIVATE experience, and the data suggest that chemotherapy and CDX-110 can be administered concurrently while still maintaining strong immune responses.

In September, Celldex randomized its first patient into ACT III, a definitive Phase II/III randomized study of CDX-110 with radiation and temozolomide in patients with newly-diagnosed GBM. The clinical trial is investigating the anticancer activity, impact on survival, and safety of the addition of CDX-110 vaccine to standard of care, versus standard of care alone. Celldex has currently enlisted 18 clinical centers throughout the United States, and also recently received approval from Health Canada to open enrollment in Canada. Furthermore, The National Cancer Institute (NCI) has agreed to collaborate with Celldex in expanded clinical development of CDX-110 under a Clinical Trials Agreement.

"Obtaining orphan designation for CDX-110 is an important milestone for Celldex," said Thomas Davis, M.D., Chief Medical Officer of Celldex Therapeutics. "Approval to expand clinical research into Canada and the scientific and clinical collaboration from the National Cancer Institute all promote our ability to fully explore the promise of CDX-110."

About CDX-110

CDX-110 is an investigational immunotherapy that targets the tumor specific molecule EGFRvIII, a functional variant of the epidermal growth factor receptor (EGFR), which is a protein that has been well validated as a target for cancer therapy. This particular variant, EGFRvIII occurs in about 40 percent of Glioblastoma Multiforme (GBM) patients. It was discovered in a collaborative effort between Dr. Bert Vogelstein and Dr Albert Wong at Johns Hopkins University and Dr. Darell Bigner at Duke University. Unlike EGFR, EGFRvIII is not present in normal tissues, suggesting this target will enable the development of a tumor-specific therapy for cancer patients. Furthermore, EGFRvIII is a transforming oncogene that can directly contribute to cancer cell growth. While originally discovered in GBM, the most common and aggressive form of brain cancer, the expression of EGFRvIII has also been observed in various other cancers such as breast, ovarian, metastatic prostate, colorectal, and head & neck cancers. Celldex has exclusive rights to EGFRvIII vaccines and is pursuing the development of CDX-110 for GBM therapy, as well as in other cancers through additional clinical studies.

About Orphan Drug Designation

Orphan drug designation grants special status to promising new therapies that treat rare diseases or conditions affecting fewer than 200,000 people in the United States and entitles seven years of market exclusivity. Additionally, the sponsor of the product is offered incentives which include eligibility for research grants, certain tax benefits, protocol assistance and possible exemptions or reductions of certain regulatory fees during development or at a time of market approval.