The most promising NAMPT-IDO1 inhibitor compound, 10e (IC50 = 57.7 nM against recombinant NAMPT and 160 nM against IDO1 in HeLa cells), significantly suppressed the growth of xenografted A549/R cells (an FK866 and taxol-resistant lung cancer cell line) as a single agent and also markedly sensitized the tumors to taxol [188]. This evidence concerns the gene IDO1 and lung cancer.