However, combining PD-1 ICB with [225Ac]Ac-FAPI-46 restored responsiveness to PD-1 ICB and resulted in significant tumor regression and tumor-free survival in 5/9 animals, which was sustained for at least up to 60 days post treatment (p = 0.0015 vs. NT; p = 0.0025 vs. NT; p = 0.029 vs. PD-1 ICB) (Fig. 7C-F). Here, PDCD1 is linked to neoplasm.