Celldex has transferred the IND for CDX-110 to Pfizer and the two companies are collaborating on the design of a randomized, controlled study for CDX-110 in the treatment of GBM.

Last December, Celldex announced an amendment that converted ACT III from a randomized Phase 2b/3 study to a single-arm Phase 2 trial in which all of the patients will receive CDX-110 in combination with Temodar (temozolomide). The decision to amend the study design was based on the observation that the majority of patients receiving the standard of care (SOC) treatment in the control arm withdrew from the study following randomization.

Celldex entered the pact with Pfizer in April 2008, which granted the latter an exclusive worldwide license to CDX-110 (being evaluated for the treatment of GBM) as well as the rights to EGFRvIII therapeutic cancer vaccines for other indications. Celldex received an upfront payment of $40 million (recognized at $1 million per quarter for 9.5 years), in addition to a $10 million equity investment (781,250 shares of CLDX at fair value of $13.91 or $10.9 million at the time) from Pfizer. Pfizer agreed to fund all development costs while Celldex is eligible to receive milestone payments exceeding $390 million and ongoing sales royalties upon successful commercialization.

Medarex, which was since acquired by Bristol-Myers (NYSE: BMY) is also a major shareholder of Celldex with approximately 2.96 million shares (since selling 2 million shares in late June) as part of previous agreements that include: (1) assignment of certain patent / IP rights and a license to Medarex technology; (2) a research and commercialization agreement for certain rights to obtain exclusive commercial licenses to proprietary monoclonal antibodies; and (3) a master services agreement related to agreed upon services to be provided by Medarex such as assistance with clinical / regulatory matters.

On 9/14/09, CLDX announced that the first patient has been dosed in a Phase 1/2 study of its vaccine candidate, CDX-1401, in patients with malignant solid tumors that express NY-ESO-1. CDX-1401 is a fully human monoclonal antibody designed to selectively deliver the NY-ESO-1 antigen to dendritic cells to generate a robust immune response against cancer cells expressing NY-ESO-1.

NY-ESO-1 is a tumor-associated antigen (TAA) expressed by several different types of cancers including lung, ovarian, prostate, bladder, melanoma, liver and esophageal cancers as well as multiple myeloma. The Phase 1/2 study is a dose-escalating clinical trial aimed at determining the optimal dose for further development based on the safety, tolerability, and immunogenicity of the CDX-1401 vaccine. The trial will evaluate three different doses of the vaccine in combination with resiquimod, an activator of toll-like receptors 7 and 8.

The study will accrue approximately 36 patients with solid tumor cancers expressing the NY-ESO-1 antigen and will follow each subject for six months post-treatment AND is being conducted at multiple clinical sites in the U.S., including Yale University, Henry Ford Health System and Cornell University. According to the ClinicalTrials.gov entry for this study (NCT00948961) (last updated 9/8/09), September 2011 is the estimated date for the primary outcome measure in the trial.

CLDX is developing CDX-1307 for the treatment of metastatic or locally advanced breast, colorectal, pancreatic, ovarian, or bladder cancers that express the beta chain of human chorionic gonadotropin, known as hCG-ß, an antigen often found in tumors of these types of cancer, but not in most normal tissues. hCG-ß is an established tumor-associated antigen, and elevated hCG-ß serum levels and/or tissue expansion have also been shown to be an independent predictor of disease outcome and are associated with a more aggressive disease course in renal, colorectal, bladder and pancreatic cancers. CDX-1307 is a fusion protein composed of a mannose receptor (MR)-specific immunoglobulin human monoclonal antibody and the hCG-ß antigen.

This antibody-vaccine is designed to deliver the antigen hCG-ß to dendritic cells (DCs) and induce hCG-ß specific cellular and humoral immune responses to activate the patient's immune system against cancers that express hCG-ß.