IDO1 and non-small cell lung carcinoma: Furthermore, a different study in 67 patients with NSCLC showed that high PD-L1 and high IDO1 correlated independently in multivariate analysis with higher response rates (objective response rate was 87.5% if both positive, 60% if one of them was positive, 22.7% if both negative; only IDO1 correlated with PFS, at least in the front-line ICI setting).42