pharmaceuticals Review Micro- and Nano-Based Transdermal Delivery Systems of Photosensitizing Drugs for the Treatment of Cutaneous Malignancies Isabella Portugal 1, Sona Jain 1 , Patrícia Severino 1 and Ronny Priefer 2,* 1 Programa de Pós-Graduação em Biotecnologia Industrial, Universidade Tiradentes, Aracaju 49032-490, Brazil;
[email protected] (I.P.);
[email protected] (S.J.);
[email protected] (P.S.) 2 Massachusetts College of Pharmacy and Health Sciences, University, Boston, MA 02115, USA * Correspondence:
[email protected] Abstract: Photodynamic therapy is one of the more unique cancer treatment options available in today’s arsenal against this devastating disease. It has historically been explored in cutaneous lesions due to the possibility of focal/specific effects and minimization of adverse events. Advances in drug delivery have mostly been based on biomaterials, such as liposomal and hybrid lipoidal vesicles, nanoemulsions, microneedling, and laser-assisted photosensitizer delivery systems. This review summarizes the most promising approaches to enhancing the photosensitizers’ transdermal delivery efficacy for the photodynamic treatment for cutaneous pre-cancerous lesions and skin cancers. Additionally, discussions on strategies and advantages in these approaches, as well as summarized challenges, perspectives, and translational potential for future applications, will be discussed. Citation: Portugal, I.; Jain, S.; Severino, P.; Priefer, R. Micro- and Keywords: photodynamic therapy; drug delivery; transdermal; cutaneous; cancer Nano-Based Transdermal Delivery Systems of Photosensitizing Drugs for the Treatment of Cutaneous Malignancies. Pharmaceuticals 2021, 1. Introduction 14, 772. https://doi.org/10.3390/ ph14080772 In past decades, clinical demands for the utilization of photosensitizers (PSs) have increased with the advent of photodynamic therapy (PDT).