Effect of anfibatide on shigatoxin-induced TTP in Adamts13^−/−mice. Platelet counts in Adamts13^−/− (CAST/Ei) mice treated with (A) PBS, (B) 30 ng/g body weight, (C) 60 ng/g body weight, and (D) 90 ng/g body weight, respectively, after being challenged with Stx-2 (250 pg/g body weight). (E) The thrombocytopenia-free survival over time. Here, thrombocytopenia was defined by 30% drop in platelet counts from the baseline. Statistical analysis was determined using analysis of variance (ANOVA) by Prism 7. **, ***, and **** indicate that P values are <.05, <.01, and <.001, respectively, when comparing with the platelet counts on day 0 (D0). ns, No statistical significance (P >.05).