Use of dermograph for improvement of PpIX precursor's delivery in photodynamic therapy: Experimental and clinical pilot studies

Author(s)

Requena, Michelle Barreto ^[1] ; Russignoli, Pedro Ernesto ^[1] ; Vollet-Filho, Jose Dirceu ^[1] ; Salvio, Ana Gabriela ^[2] ; Fortunato, Thereza Cury ^[1] ; Pratavieira, Sebastiao ^[1] ; Bagnato, Vanderlei Salvador ^[1]

Affiliation

^[1] Univ Sao Paulo, Sao Carlos Inst Phys, POB 369, BR-13560970 Sao Carlos, SP - Brazil

^[2] Amaral Carvalho Hosp, Skin Dept, Jau, SP - Brazil

• Document type: Journal article
• Source: Photodiagnosis and Photodynamic Therapy; v. 29, MAR 2020.
• Web of Science Citations: 0

Abstract

Background: Photodynamic Therapy (PDT) is a treatment for non-melanoma skin cancer. One of the main challenges of topical PDT is to increase the precursor penetration when applied on the lesion. Protoporphyrin IX (PpIX) is an endogenous photosensitizer (PS) widely used, obtained by the administration of precursors such as aminolevulinic acid and methyl aminolevulinate. Aiming for the technique improvement by providing greater PS penetration in skin lesions, we tested a new approach for drug delivery with a minimally invasive technique. A dermograph is a device currently used in aesthetic procedures to promote skin rejuvenation or to micropigmentation. The use of dermograph for drug delivery has not been particularly explored for PDT so far, and the present study explores that approach as its main goal. Methods: This study evaluated the PpIX distribution and PDT damage in normal rat skin model; the response of dermograph application in a pilot clinical study was also investigated. Results: The animal tests showed that more homogeneous PpIX distribution and greater penetration in the tissue was observed with dermograph when compared to the topical application. Six nodular basal cell carcinoma lesions were treated with PDT using intradermal delivery by dermograph, and no recurrence was observed after 28 months of follow-up. Conclusions: The precursor's penetration improvement and the consequent increase in PpIX distribution in-depth both favor PDT response, providing upgrades concerning problems that hinder the clinical practice acceptance. (AU)

• FAPESP's process: 09/54035-4 - Facility for advanced studies of biosystems and nanostructured materials
• Grantee: Igor Polikarpov
• Support Opportunities: Multi-user Equipment Program
• FAPESP's process: 13/07276-1 - CEPOF - Optics and Photonic Research Center
• Grantee: Vanderlei Salvador Bagnato
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 14/50857-8 - National Institute in Basic Optics and Applied to Life Sciences
• Grantee: Vanderlei Salvador Bagnato
• Support Opportunities: Research Projects - Thematic Grants