CpG-gp-E2

**CpG-gp-E2** is an investigational therapeutic cancer vaccine developed at the University of California, Irvine. It is a self-assembling, nonviral pyruvate dehydrogenase E2 protein nanoparticle functionalized with a melanoma-associated glycoprotein 100 epitope and CpG oligodeoxynucleotide 1826. The gp100 antigen component is intended to prime gp100-specific cytotoxic CD8-positive T-cell responses against melanoma cells, while CpG activates Toll-like receptor 9-mediated innate immune signaling and promotes antigen-presenting-cell activation. In mouse B16 melanoma models, prophylactic subcutaneous vaccination increased gp100-specific CD8-positive T-cell responses, delayed tumor growth, and prolonged survival; it was also evaluated preclinically with anti-PD-1 therapy.