However, many CRC patients remain resistant to immunotherapy.[3] The response rates to PD‐1/PD‐L1 blockade vary from 13% to 69%, depending on tumor type.[4, 5] In order to enhance the efficacy of immune checkpoint inhibitors (ICIs) and improve patient responses, researchers have proposed improved strategies targeting three reasons for resistance. The gene discussed is PDCD1; the disease is neoplasm.