I have some post-inflammatory hyperpigmentation and keep seeing peptide brighteners like Melanostatine-5 (nonapeptide-1) marketed as gentler alternatives to the heavier hitters, working upstream by blocking alpha-MSH signaling rather than inhibiting tyrosinase directly.
Question for the science-minded here: is the human evidence for peptide brighteners anywhere near that of the more established actives, or is this another 'plausible mechanism, thin outcome data' situation? And practically, for PIH specifically, does the mechanism even target the right pathway?