Pirfenidone inhibits post-traumatic proliferative vitreoretinopathy

Area of Science:

• Ophthalmology
• Regenerative Medicine
• Pharmacology

Background:

• Proliferative vitreoretinopathy (PVR) is a severe complication of penetrating ocular injury.
• Current treatments for PVR have limitations, necessitating novel therapeutic approaches.

Purpose of the Study:

• To evaluate the efficacy and safety of intravitreal pirfenidone for inhibiting PVR.
• To assess pirfenidone's impact on fibrotic markers and cytokine expression in a rabbit penetrating ocular injury model.

Main Methods:

• Penetrating ocular trauma was induced in rabbit eyes.
• Eyes were treated with either phosphate-buffered saline (PBS) or 0.5% pirfenidone intravitreally.
• PVR development was assessed clinically and histopathologically.
• Immunohistochemistry and RT-PCR were used to analyze fibrotic changes and cytokine expression.
• Pirfenidone's vitreous availability and ocular safety were evaluated.

Main Results:

• Pirfenidone treatment significantly prevented PVR formation compared to PBS controls.
• Histopathology confirmed reduced fibrotic changes, with decreased expression of collagen-I, alpha smooth muscle actin (αSMA), and transforming growth factor beta (TGFβ).
• Pirfenidone inhibited elevated cytokine gene expression and demonstrated no adverse effects on ocular tissues, intraocular pressure, or electroretinography.

Conclusions:

• Intravitreal pirfenidone demonstrates significant potential as a therapeutic agent for preventing PVR.
• The safety profile and efficacy in this animal model support further clinical trials for PVR treatment.