Microneedle-mediated transdermal drug delivery for treating diverse skin diseases

Abstract

Transdermal drug delivery is an attractive route for dermatological disease therapy because it can directly target the lesion site on the skin, reduce adverse reactions associated with systemic administration, and improve patient compliance. However, the stratum corneum, as the main skin barrier, severely limits transdermal drug penetration, with compromised bioavailability. Microneedles (MNs), which are leveraged to markedly improve the penetration of therapeutic agents by piercing the stratum corneum and creating hundreds of reversible microchannels in a minimally invasive manner, have been envisioned as a milestone for effective transdermal drug delivery, especially for superficial disease therapy. Here, the emergence of versatile MNs for the transdermal delivery of various drugs is reviewed, particularly focusing on the application of MNs for the treatment of diverse skin diseases, including superficial tumors, scars, psoriasis, herpes, acne, and alopecia. Additionally, the promises and challenges of the widespread translation of MN-mediated transdermal drug delivery in the dermatology field are summarized. Statement of Significance: Various recent reviews on microneedles have covered needle types, materials, and manufacturing methods, as well as their applications in diabetes and cancer therapy. This review provides a different perspective, focusing on the application of microneedles for treating diverse skin diseases, including skin tumors, scars, psoriasis, herpes, acne, and alopecia. In addition, this review also discusses the concerns about the use of microneedles and the efforts needed for their widespread clinical application in the future, providing a valuable reference to translate microneedles for the treatment of skin diseases from the laboratory to the clinic.