Bletilla striata polysaccharide-based dissolving microneedle patch integrated with nanoparticles for promoting hair regrowth.

Hair loss (alopecia) has become a condition that plagues billions of people worldwide, which can occur at any age. Alopecia severely reduces the life quality and affects the self-esteem of patients, especially in adolescents. Due to the deficiency of current therapeutic formulations, such as frequent dosing, low bioavailability, significant side effects and high cost, it is urgent to develop a safe and effective strategy for the treatment of hair loss. Herein, we designed a dissolving microneedle patch (TFB@NP-MNs) integrated with tofacitinib-loaded nanoparticles (TFB@NP). Hyaluronic acid and Bletilla striata polysaccharide constituted the main body of microneedles and promoted the sustained release of TFB. MNs patch invasively punctured into the stratum corneum and delivered TFB with sustained release for 48 h. Compared with daily topical administration of commercially available TFB, in vivo results showed that TFB@NP-MNs significantly increased the number of hair follicles and had a similar or superior hair regeneration effect with less drug, which significantly improved drug delivery efficiency and the dual function of mechanical stimulation and the long-term release of TFB. These results suggest that this MN patch may offer a promising strategy for alopecia therapy clinically by reducing dosing frequency and increasing patient compliance.