Evaluation of a new oil adjuvant for use in peptide-based cancer vaccination

Vaccine therapies are increasingly being used for the treatment of various diseases, and the antigen molecules themselves are being expanded from whole microorganisms to fine molecules such as peptides. Accordingly, there is a need for new adjuvants to support these new applications. In this paper, we used pharmaceutical grade mineral oil and sorbitan monooleate to develop a new oil adjuvant formula, NH(2) , and investigated its effects on peptide vaccination at both the pre-clinical and clinical levels. The adjuvant effect of NH(2) on peptide-induced cellular immunity in mice was superior to that of Montanide ISA51VG, a commercially available incomplete Freund's adjuvant for clinical use, although no significant difference was observed between the two adjuvants on peptide-induced humoral immunity. The adjuvant effects of NH(2) were also confirmed in a Phase-I clinical trial of peptide vaccines for patients with advanced cancers. These results suggest that NH(2) is a suitable adjuvant for peptide vaccination, particularly for cancer vaccines (Phase-I clinical trial of pan-HLA type personalized peptide vaccine for advanced cancer patients, UMIN clinical trial registry number: UMIN 000000619).