Early murine studies conducted to test the efficacy of anti-PD-1, anti-PD-L1, and anti-CTLA-4 using orthotopic, syngeneic GBM models were very promising, demonstrating long-term tumor eradication using single-agent therapy and a cure rate of 75% when combining anti-CTLA-4 with anti-PD-1 (7). Here, CTLA4 is linked to neoplasm.