CTLA4 and head and neck squamous cell carcinoma: Promisingly, in late 2020, the biotechnology company ImmunoGenesis announced that a Phase 2 study supported by these data will investigate evofosfamide in combination with both anti-CTLA-4 and anti-PD-1 in patients with castration-resistant prostate cancer, pancreatic ductal adenocarcinoma, and HPV-negative HNSCC [157].