PDCD1 and neoplasm: While a three 2-fold dose curve is limited in dose numbers, by comparing percent inhibition of tumor growth, it appeared that combining Alphataxin with anti-PD-1 antibody had an additive effect, as opposed to synergistic effect, which was expected because the two drugs target separate biological pathways; more sophisticated methods would be informative using a larger set of dose curves (Table 1) (36).