Intravitreal therapy-success stories and challenges

Intravitreal injections have revolutionized the treatment of various sight-threatening diseases of the posterior segment of the eye. Initially explored for treatment of bacterial endophthalmitis, intravitreal injections rapidly expanded to combat retinal vascular disease in particular. Especially anti-vascular endothelial growth factor agents have emerged as a cornerstone of intravitreal therapy, targeting neovascular age-related macular degeneration and diabetic macular edema as important examples. Advances continue, with novel therapies such as complement inhibitors now available as treatment for geographic atrophy secondary to non-neovascular age-related macular degeneration, offering hope for a previously untreatable condition. Pioneering approaches such as the port delivery system and intravitreal gene therapy aim to improve treatment efficacy while minimizing patient burden. Despite notable successes, challenges for intravitreal therapies persist, including ocular and systemic complications and high treatment burden. Future research endeavors aim to address these challenges and enhance treatment outcomes. This comprehensive review critically evaluates the efficacy, safety, and cost-effectiveness of intravitreal injections, delving into emerging trends and future directions.