Dissolving microneedles for inflammatory diseases: Advances in formulation strategies and therapeutic applications

Inflammatory diseases affecting various organs, such as arthritis in the joints, psoriasis of the skin, and keratitis in the eyes, often require long-term anti-inflammatory therapy, necessitating the development of innovative treatment strategies. Dissolving microneedles (DMNs) have emerged as promising transdermal, transmucosal, and transocular drug delivery systems for treating inflammatory diseases. DMNs are composed of biocompatible polymers that completely dissolve upon administration, thereby eliminating the risk of sharp waste. As a minimally invasive therapeutic approach, DMNs allow for direct application to the site of inflammation, enhancing drug bioavailability and reducing systemic toxicity compared with conventional oral administration routes. This review summarizes recent advances in DMN formulations for inflammatory disease therapy, including production methods and innovative DMN designs, such as hybrid, bilayer, core-shell, and stimuli-responsive systems. The integration of additional technologies, including drug polymer-based encapsulation, nanoparticles, nanocarriers, and mesoporous silica, has been shown to enhance the therapeutic potential of active compounds in in vivo studies using inflammatory disease models, with superior outcomes reported in clinical evaluations. Nevertheless, further research is required to analyze application-related factors, such as the location and condition of the administration area, drug release kinetics, and dosage loading, to fully elucidate the underlying mechanisms. Moreover, a more in-depth investigation of the regulatory challenges and clinical monitoring is necessary to optimize the clinical potential of DMNs. Despite these challenges, DMNs remain a highly promising platform for targeted and effective drug delivery in the management of inflammatory diseases.