MI131

MI131 is a topical small molecule drug candidate developed by Nanjing Mainoway Pharmaceutical (南京迈诺威医药科技有限公司) for the treatment of androgenetic alopecia (AGA). It functions as a phosphodiesterase type 5 (PDE5) inhibitor. While PDE5 inhibitors are traditionally used for erectile dysfunction and pulmonary arterial hypertension, MI131 is specifically formulated for localized application to the scalp. The mechanism of action involves inhibiting the breakdown of cyclic guanosine monophosphate (cGMP), which promotes vasodilation and enhances microcirculation around hair follicles. This improved blood flow is intended to deliver more nutrients and oxygen to the follicles, potentially reversing miniaturization and stimulating the transition of hair follicles from the telogen (resting) phase to the anagen (growth) phase. The topical formulation is designed to maximize local efficacy while minimizing systemic absorption and the associated risk of systemic side effects.