Baricitinib-Loaded Separable Microneedle Array Patch (S-Map) Based on Hyaluronic Acid for Alopecia Areata Therapy

Separable and dissolvable microneedle array patch mainly based on hyaluronic acid was designed for the topical delivery of baricitinib aiming at the therapy of alopecia areata (AA). Locoregional injection of separable microneedle array patch (S-MAP) may avoid the systemic side effects of oral administration and it can be injected without pain compared to typical intradermal injection. Baricitinib (which has poor aqueous solubility) was homogeneously suspended with sodium carboxymethylcellulose and that mixture was blended with other pharmaceutical excipients, such as hyaluronic acid, sucrose, and Tween 80, for fabricating S-MAP structure. Crystalline property of baricitinib was transformed into an amorphous state during drying processes and it may contribute to the immediate drug dissolution within 30 min. Proper insertion of baricitinib-loaded S-MAP in porcine skin tissue and mouse skin was demonstrated by optical coherence tomography and near-infrared fluorescence imaging, respectively. Topical injection of baricitinib-loaded S-MAP system to the AA lesion of mouse models exhibited significantly higher hair growth portion compared to control group (S-MAP: 68% vs control: 33%, p < 0.05). All these findings support that designed baricitinib S-MAP system can be used efficiently and safely with pain-free and self-medication properties for the therapy of AA.