The common immunotherapy agents used in combination treatment for GBM clinical trials mainly include durvalumab (anti-PD-L1), atezolizumab (anti-PD-L1), avelumab (anti-PD-L1), pembrolizumab (anti-PD-1), nivolumab (anti-PD-1), and ipilimumab (anti-CTLA-4). Here, CTLA4 is linked to glioblastoma.