Figure 2. Combination therapy with Cy/GVAX and PD-1 or PD-L1 blockade improves clinical outcomes in a PDA mouse model.
(A) Schema of tumor implantation by the hemispleen procedure and treatment with Cy, GVAX and αPD-1/αPD-L1 blockade as indicated. C57Bl/6 mice were challenged on day 0 with 2 x 106 Panc02 tumor cells followed by administration of 100 mg/kg of Cy on day 3 and irradiated whole-cell vaccine on day 4, 7, 14 and 21. Anti-PD-1, anti-PD-L1 or IgG (5 mg/kg IP) were administered IP twice weekly until death starting on day 3. (B) Kaplan-Meier survival curves of mice that were implanted with PDA cells and were treated with different combinations of Cy, GVAX and the αPD-1 antibody. The percentages of mice that remained disease free at day 90 following tumor implantation and therapy with (C) Cy, GVAX and/or αPD-1 or (D) Cy, GVAX and αPD-L1 are shown. All the p values were yielded by comparing GVAX and/or αPD-1/αPD-L1 treatment groups with IgG treated group. (E) Kaplan-Meier survival curves of mice that were implanted with Panc02 cells via hemispleen technique and treated with different combinations of Cy, GVAX and αPD-L1 antibody. Data are represented as results obtained from experiments with 8-10 mice per group that were repeated at least twice. N.S. not significant.