Fig. 4.

GMCI/anti–PD-1 combination therapy improves outcome in the syngeneic GL261Luc2 mouse glioblastoma tumor model. (A) Treatment scheme and Kaplan–Meier survival curves following intratumoral delivery of AdV-tk at day 7 after GL261Luc2 injection (1 × 10⁵ cells) in the right hemisphere of the brain. Twenty milligrams per kilogram GCV/twice daily for 10 days and 4 doses of 200 μg anti–PD-1 were systemically administered. (B) BLI data for 3 tumor-bearing mice from each treatment group at day 21. (C) Long-term tumor-free survivors (LTS, >100 days) initially treated with the GMCI, anti–PD-1, and combination, or treatment-naïve controls following intracranial inoculation of 1 × 10⁵ GL261Luc2 cells. No treatment was given after tumor rechallenge in the left hemisphere. (D) BLI data for 3 rechallenged mice from each treatment group at day 15 post tumor implantation. All the LTS-mice show no residual tumor. (E) Kaplan–Meier survival curves following intratumoral delivery of AdV-tk at day 4 after CT-2ALuc injection (4 × 10⁵ cells). The Mantel–Cox test was used to determine statistical significance (***P ≤ 0.0001, ***P ≤ 0.001, **P ≤ 0.01, *P ≤ 0.05).