To assess the impact of NMD-escape mutations on anti-tumor immune response, we assessed the association between NMD-escape mutation count and CPI clinical benefit in four independent melanoma cohorts with matched DNA and RNA sequencing data: Van Allen et al.8 (n = 33, anti-CTLA-4 treated), Snyder et al.7 (n = 21, anti-CTLA-4 treated), Hugo et al.4 (n = 25, anti-PD-1 treated) and Riaz et al.20 (n = 24, anti-PD-1). The gene discussed is CTLA4; the disease is melanoma.