Systematic literature Review for the Association of Biomarkers with Efficacy of Anti-PD-1 Inhibitors in Advanced Melanoma

Aim: Summarize the literature assessing biomarkers in predicting efficacy of anti-PD-1 therapy for patients with high-risk unresectable or metastatic melanoma. Materials & methods: Relevant studies were identified via a systematic literature review. Results: About 334 unique biomarkers or biomarker combinations were identified from 121 citations. Neutrophil-to-lymphocyte ratio was the most frequently studied biomarker, followed by C-reactive protein. Fifty-nine biomarkers were significantly associated with overall survival (OS), 51 with progression-free survival (PFS) and 44 with response. Twenty biomarkers were associated with both OS and PFS; two were associated with OS, PFS and response (MHC-II and tumor mutational burden). Conclusion: Numerous biomarkers could potentially predict the efficacy of anti-PD-1-based therapy for melanoma patients. However, confirmatory studies are needed as well as determination of implications for clinical decision-making.