CD274 and neoplasm: A similar comparison can be made with [89Zr]Zr-atezolizumab from reported in vitro and in vivo studies with H1975 tumor cells and xenografts, respectively.37,38 Using the Kd (2 nmol/L) and the Bmax of 6 nmol/L for the PD-L1 concentration in H1975 tumor cells (in vitro), the predicted T: NT ratio is 3:1 which is comparable to the in vivo H1975 T: M ratios ranging from 5:1 and 3:1 (at 48 hours and 72 hours, respectively, associated mass of the dose:∼ 20 μg).