The patients received an arginase-1 peptide vaccine comprising three 20-mer peptides from the ARG1 immunological "hot spot" region in combination with the adjuvant Montanide ISA-51...Nine (90%) of ten patients had measurable peptide-specific responses in the periphery blood, and two (20%) of ten patients attained stable disease on protocol treatment. https://clinicaltrials.gov/ct2/show/NCT03689192, identifier NCT03689192.
Our study provides evidence that IO112 immune therapy against arginase-1 is an attractive way of modulating the immune suppressive tumor microenvironment for therapeutic benefit. With this rationale, we are currently undertaking IND enabling studies to explore this approach in a clinical setting.