Carrier Polymer-Free Dissolvable Microneedles Enable Superhigh Drug Payload for Percutaneous Protein Delivery

Abstract

Microneedle (MN) patches present a painless alternative for transdermal delivery of monoclonal antibodies (mAbs), yet existing dissolvable MNs are hindered by a low drug-loading capacity (DLC). This study introduces a carrier-free approach for fabricating mAb MNs by a solution-casting method, providing a superhigh drug-payload MN platform (DLC around 70%). Additionally, the use of concentrated proteins prevents interpenetration between the backing layer and the tip, assuring the dosage accuracy of the therapeutic antibodies. Physicochemical characteristics, including mechanical strength, dissolvability, and skin permeability, were evaluated and compared with conventional PVP K17 (poly(vinylpyrrolidone), K17) microneedles. Finally, the transdermal performance of protein dMNs was assessed using IL-17A (Iinterleukin-17A) antibody as a model protein drug, with in vivo therapeutic efficacy evaluated in a psoriatic mouse model. The results demonstrate the feasibility and effectiveness of excipient-free dMNs for mAb delivery, significantly improving the drug-loading capacity, while mitigating safety concerns associated with carrier polymers.