LDE225 is a novel and specific, orally bioavailable Smo inhibitor with an IC50 of 11 nM. It has been shown to potentially inhibit Hh-and Smo-dependent proliferation in vivo. It also induced the regression of preformed basaloid lesions with an IC50 of <150 nM and almost complete regression at 1.5 μM. Topical application of a 1% LDE225 solution to depilated skin of C57/BL6 mice completely inhibited hair growth during anagen phase as well as the expression of the Hh-pathway target genes (Gli1, Gli2, Sox9, and N-Myc) and partial inhibition was obtained when applying a 0.3% solution.