VLS-101 inhibits tumor growth in subcutaneous RS-PDX models. For the RS-PDX models IP867/17 (A), RS1316 (B), RS1050 (C), and RS9737 (D), RS cells were subcutaneously injected into both flanks of NSG mice. After palpable tumors were evident (tumor volume of ∼0.2 cm3), animals were randomly assigned to vehicle, VLS 101 2.5 mg/kg or VLS-101 5 mg/kg. Drugs were administered IV every 4 days as indicated by arrows (Tx) and mice were monitored for tumor growth in a watch-and-wait (W&W) period after the conclusion of therapy. Tumor masses were measured using a digital caliper. Left panels display individual mean and standard deviation values for tumor masses at the end of treatment on days 47 (A), 48 (B), 47 (C), and 28 (D) with data evaluated using Mann-Whitney tests. Center panels display mean and standard error of the mean values for tumor masses with data evaluated using the multiple-sample Student t tests. Right panels display Kaplan-Meier survival curves for mice with tick marks indicating censored values and comparisons analyzed with log-rank Mantel-Cox tests. In all figures, comparisons are to vehicle treatment. *P < .05; **P < .01; ***P < .001; ****P < .0001.