Novel ALK5 Inhibitor TP0427736 Reduces TGF-β Induced Growth Inhibition in Human Outer Root Sheath Cells and Elongates Anagen Phase in Mouse Hair Follicles

The document presents a study on the ALK5 inhibitor TP0427736, which showed potential as a treatment for androgenetic alopecia (AGA) by reducing TGF-β induced growth inhibition in human outer root sheath cells and elongating the anagen phase in mouse hair follicles. TP0427736 was found to inhibit ALK5 kinase activity with an IC50 of 2.72 nM and decrease Smad2/3 phosphorylation in A549 cells. It also rescued the proliferation of human outer root sheath cells suppressed by TGF-β1 and reduced Smad2 phosphorylation in mouse skin. The application of TP0427736 in mice significantly decreased the shortening of hair follicle length during the transition from the late anagen phase to the catagen phase. The study suggests that TP0427736 could be a promising and safer alternative to current AGA treatments, as it may avoid side effects associated with androgen blockade. The number of subjects involved in the study was not provided.