Apafant (WEB 2086), a chemical probe, is a potent platelet-activating factor (PAF) antagonist, inhibits PAF binding to human PAF receptors with a Ki of 9.9 nM. Apafant increases the gene expression of PAF-r, α-globin, β-globin, decreases the c-myb gene expression. Apafant shows a protective effect on alkyl-PAF-mediated lethalit[1][2][3].