CTLA4 and colorectal carcinoma: However, a recent randomised phase II study showed a modest survival benefit from the combination of durvalumab (anti‐PD‐L1) and tremelimumab (anti‐CTLA‐4) in patients with advanced treatment‐refractory CRC compared to best supportive care, suggesting that a subset of patients with MSS mCRC may benefit from treatment with ICB.14