NPC-1C is a chimeric immunoglobulin molecule comprised from the variable region of the heavy chain and light chain of murine NPC-1, genetically engineered in-frame with the constant regions of a human IgG1 isotype. NPC-1, the predecessor of NPC-1C, was derived from a Tumor Associated Antigen (TAA) based vaccine that was previously tested in a Phase 1-2 clinical trial performed in the United States in the 1980's that explored the use of TAA therapy in patients with adenocarcinoma of the colon. These early studies demonstrated safety as well as preliminary evidence of activity in these patients treated with the vaccine.