GNOS-PV01 personalized neoantigen DNA vaccine drives T-cell expansion and ~16.3-mo mOS in MGMT-unmethylated GBM

GNOS-PV01 is a personalized, multivalent neoantigen DNA therapeutic cancer vaccine (up to 40 neoantigens/patient) given adjuvantly after surgical resection and radiotherapy in the open-label, single-arm Phase 1 GT-20 trial (NCT04015700) in newly diagnosed MGMT-unmethylated glioblastoma (n=9). No serious AEs, unexpected toxicities, or DLTs were reported; vaccine-induced peripheral T-cell activation/expansion was seen in all evaluated patients except one receiving dexamethasone. 6-month PFS and 12-month OS were each 66.7%; median PFS was 8.5 months and median OS was 16.3 months with 24-month survival 33% (including one patient alive at 4 years)—numerically above historical MGMT-unmethylated outcomes with standard chemoradiation where median OS is often ~11–13 months, but cross-trial comparisons are fragile given the very small, selected cohort and single-arm design.