In particular, by targeting the clonal neoepitope, the mutant IDH1-specific peptide vaccine (IDH1-vac) has yielded, thus far, the best safety and efficacy as a single agent in newly diagnosed glioma in terms of overall response rate, progression-free survival, and overall survival compared to other trials of mutant IDH inhibitors for various types of cancer [42,51,52]. The gene discussed is IDH2; the disease is glioma.