Y6-pepVIII

Y6-pepVIII is an experimental peptide vaccine designed for the treatment of glioblastoma. It is a modified version of pepVIII, a peptide corresponding to the unique mutation site of the epidermal growth factor receptor variant III (EGFRvIII). The Y6 designation refers to a tyrosine substitution at the sixth position of the peptide, which was identified through in silico and experimental screening to maximize proteasomal cleavage and subsequent antigen presentation. This modification enhances the generation of both linear and spliced peptide fragments (proteasome-catalyzed peptide splicing) that bind to MHC class I molecules, leading to a more robust immune response. In preclinical studies, Y6-pepVIII demonstrated significantly improved survival in intracranial glioma models compared to the original pepVIII vaccine, particularly when combined with PD-1 checkpoint inhibition.