In advanced non-small cell lung cancer (NSCLC) patients who received first-line anti-PD-1 therapy plus platinum-based combination chemotherapy, pretreatment fibrinogen-albumin ratio (FAR) was identified to be an independent predictor for treatment response and independent prognostic factors.

• A total of 91 advanced NSCLC patients were treated with at least two cycles of systemic first-line anti-PD-1 therapy plus platinum-based combination chemotherapy.

• In multivariate logistic regression analysis, independent predictors for objective response rate included N stage (N2-3) and high FAR (≥ 0.175, optimal cutoff value).

• High FAR (≥ 0.145) was found to be independent prognostic factors in multivariate Cox regression analysis of progression-free survival and overall survival.

• The high FAR (≥ 0.145) group had significantly shorter progression-free survival and overall survival compared with those in the low FAR (< 0.145) group.