WHI-P180 is also an active inhibitor of IgE-mediated mast cell responses. The elimination half-life of WHI-P180 in CD-1 mice (BALB/c mice) following i.v., i.p., or p.o. administration is less than 10 min. Systemic clearance of WHI-P180 is 6742 mL/h/kg in CD-I mice and 8188 mL/h/kg in BALB/c mice. Notably, WHI-P180, when administered in two consecutive nontoxic i.p. bolus doses of 25 mg/kg, inhibits IgE/antigen-induced vascular hyperpermeability in a well-characterized murine model of passive cutaneous anaphylaxis [3].