ADVANCES IN TRANSDERMAL PATCH FORMULATION FOR CONTROLLED DELIVERY OF PIOGLITAZONE

Diabetes mellitus remains a global health challenge that demands long-term, safe, and patient-centric therapeutic strategies. Pioglitazone, a potent insulin sensitizer belonging to the thiazolidinedione class, plays a significant role in the management of type 2 diabetes mellitus; however, its clinical utility is often compromised by limitations associated with oral administration. Extensive first-pass hepatic metabolism, variable bioavailability, gastrointestinal disturbances, dose-dependent adverse effects, and the requirement for prolonged daily dosing contribute to suboptimal therapeutic outcomes and poor patient compliance. In this context, transdermal drug delivery systems have gained increasing attention as an innovative platform for the controlled and sustained delivery of antidiabetic agents. Transdermal patches offer distinct advantages, including bypassing first-pass metabolism, maintaining steady plasma drug concentrations, minimizing systemic side effects, and enhancing patient adherence during chronic therapy. This review critically examines recent advances in the development of transdermal patch formulations for pioglitazone, emphasizing formulation design strategies that enable controlled drug release and improved skin permeation. Various polymeric matrices, plasticizers, adhesives, and chemical penetration enhancers employed in pioglitazone transdermal patches are discussed, highlighting their influence on mechanical integrity, drug release kinetics, and permeation behavior. In addition, key evaluation parameters such as physicochemical characterization, mechanical strength, in-vitro release, ex-vivo skin permeation, stability, and skin irritation studies are systematically summarized. The review also addresses current formulation challenges and regulatory considerations while exploring future perspectives, including advanced polymer systems and clinically translatable designs. Overall, transdermal patch-based delivery of pioglitazone represents a promising, non-invasive, and patient-friendly approach for improving long-term diabetes management.