Pirfenidone Clinical Study 3

An experimental, longitudinal, prospective, and comparative study to evaluate the efficacy of topical pirfenidone in accelerating the epithelialization process in split-thickness skin grafts (STSGs) donor sites.

• 24 patients requiring STSGs with donor sites of at least 7.5×10cm were included in this study,
• After harvesting, the donor sites were randomly treated with either non-adherent gauze or topical pirfenidone and covered with non-adherent gauze.
• Topical pirfenidone was applied every 8 h (q-8 h) for 6 days.
• To assess epithelialization, biopsies were taken at day 7 and 10 in the pirfenidone group, and at day 10 in the control group.
• The percentage of epithelialization was assessed on days 7 and 10 through clinical photographs.
• Pain was evaluated with a visual analog scale.
• Adverse events related to the administration of pirfenidone were investigated.

• The application of pirfenidone significantly accelerated epithelialization.
• The thickness of epithelium was 75.10±59.35μ at day 10 for the control group; and (98.21±5.78μm at day 7, and 108±21.67μm at day 10 for the pirfenidone group (p=0.03 at day 7 vs control and p=0.01 at day 10 vs control). (Figure 7A)
• Epithelization rate was 88.58% at day 10 for the control group, 98.74% at day 7, and 99.52% at day 10 for the pirfenidone group (p<0.05). (Figure 7B)
• An epithelial layer was present in all biopsies, confirming that the areas deemed as “epithelialized” were indeed covered with epithelium.
• The pirfenidone group reported chronic perivascular inflammatory infiltrate associated with signs of epithelialization, epidermis thickness of 9.4mm, Normal granular layer, mild hyperkeratosis, and presence of blood vessels in the superior dermis. Presence of elastic and collagen fibers.
• The control group, pathology reported epidermal thickness of 4.9mm, hypogranulosis, mild hyperkeratosis, presence of blood vessels in superficial dermis, perivascular swelling in superior dermis, and presence of collagen and elastic fibers.
• The application of pirfenidone was moderately painful during the first few days, after which it was better tolerated.
• None of the patients in the pirfenidone group developed any side effects at the wound site.
• There were no hepatic or renal alterations throughout the study.

Pirfenidone was effective in accelerating the epithelialization of STSG donor sites.