CTLA4 and neoplasm: As neoantigen‐specific CD8+ T‐cell responses paralleled tumor regression, it was verified that anti‐PD‐1 therapy could enhance neoantigen‐specific T‐cell reactivity.22 Furthermore, a signature defined by mutation‐derived neoepitopes could potentially be used to predict durable clinical benefit from the CTLA‐4 blockade in melanoma.23 However, this neoepitope signature was subsequently proven to be not predictive using the same dataset24 and in another study of anti‐CTLA‐4 dataset,25 indicating the defects of neoantigen peptide as prognostic biomarkers.