April 2017 in “Journal of Investigative Dermatology”
Early and late matrix progenitors in hair follicles create different cell layers, with early ones forming the companion layer and later ones forming the inner root sheath and hair shaft.
Hair follicle stem cells remain in bald individuals, but progenitorcells do not, raising questions about hair regrowth claims by Pelage. PP405 is discussed as a potential treatment, with skepticism about its effectiveness compared to existing treatments like Minoxidil and Finasteride.
AMP-303 and AMP-601 are new hair loss treatments targeting dermal papilla cells, with AMP-303 showing early efficacy in transitioning vellus hairs to terminal hairs after one injection. Further clinical trials are planned, and these treatments are seen as promising due to their biologic approach and less frequent application compared to daily treatments.
PP405 is ineffective for miniaturized, fibrosed hair follicles in androgenetic alopecia. AMP303 may activate hair follicle stem cells, but minoxidil and finasteride are still the main treatments.
Hair loss is linked to cellular physiology and the IGF-1 to TGF-B1 ratio, not just androgen sensitivity. The theory lacks evidence, while finasteride and minoxidil are effective treatments.
PP405 is discussed as a potential hair loss treatment, but its effectiveness and safety are uncertain. Some users express skepticism, while others are hopeful, comparing it to existing treatments like Minoxidil and Finasteride.