IDH1-vac (IDH1R132H peptide vaccine) links immune response to long OS in IDH1-mutant astrocytoma

IDH1-vac is a mutation-specific long-peptide vaccine targeting the shared clonal driver neoepitope IDH1R132H (MHC class II–restricted) and was integrated with standard-of-care chemoradiation in the multicenter, single-arm, open-label, first-in-human Phase 1 NOA16 trial (n=33) in newly diagnosed WHO 2007 grade III–IV IDH1R132H+ astrocytoma (NCT02454634). At long-term follow-up, 8-year PFS and OS rates were 0.42 (CI 0.24–0.59) and 0.66 (CI 0.46–0.79), respectively; in grade IV astrocytoma, median OS was 106.1 months (CI 39.6–NE), exceeding published grade IV IDH-mutant astrocytoma benchmarks (~31.6–56.4 months) cited by the authors. Sustained anti-IDH1R132H antibody responses tracked with favorable clinical course, and vaccine-induced T cells were detected within an inflamed lesion during vaccine-associated pseudoprogression but not in early progressors; no new late safety signals were emphasized in the abstract (primary endpoints previously met for safety/immunogenicity).