Combining different doses of Doxil and IL-18 for optimized therapy. (A) Kaplan-Meier survival curves show the effects of Doxil therapy at 2.5, 5, or 7.5 mg/Kg when combined with different doses of IL-18 and administered to ID8-Vegf tumor bearing mice (n = 5/dose group). Mice received IL-18 doses of 10 (green), 30 (teal), or 100 (blue) ug/mouse, or no IL-18 as control (red). Mice were treated with i.p. bolus injections of Doxil or 5% dextrose control (black) given weekly for 4 weeks. Chemotherapy treatment started one week after i.p. tumor inoculation; IL-18 treatment began 2 days later. IL-18 or 0.9% saline was given s.c. at 10, 30 or 100 μg/mouse, daily for 50 days. (B) Improved survival was determined in combination therapy groups using the hazard ratios (HR) for each treatment group compared to the control group and their 95% confidence intervals. Combinations of IL-18 and Doxil showing improved survival HR are shaded.