Figure A1.

Re-calculation of the EC₅₀ value for BMS-1166 according to the optimized method. Initial calculations for the biphenyl BMS molecules were carried out without any restrictions to the fitting parameters [5]. With time, we learned that this may lead to depreciated EC₅₀ values, since the upper plateau of the experimental points, and thus the upper asymptote of the fitted curve may be lowered by unspecific effects such as cell toxicity. Therefore, in subsequent analyses, we fixed the upper asymptote of curve fittings at a value observed for therapeutic anti-PD-L1 antibody, either atezolizumab or durvalumab. These values were considered maximal effector Jurkat T cells activation levels achievable in the assay. As shown in this figure, such an analysis leads to determining higher EC₅₀ values, which in our opinion are more relevant and better reflect the real bioactivity in the ICB assay.