A recent study found that patients with diabetic macular edema (DME) undergoing treatment in the clinical setting receive fewer anti-vascular endothelial growth factor (VEGF) injections when compared to individuals enrolled in clinical trials.

This retrospective analysis of the American Academy of Ophthalmology’s Intelligent Research in Sight (IRIS) Registry examined anti-VEGF intravitreal therapy patterns and long-term visual outcomes among treatment-naïve patients with diabetic macular edema (n=190,345). The key study outcomes included the annualized number of injections, change in VA and anti-VEGF agents.

The DME treatment landscape is changing with the advent of novel treatment options. Photo: Carolyn Macher, OD. Click image to enlarge.

Data showed that, after one year of anti-VEGF intravitreal therapy, eyes received a mean of 3.9 injections and gained +3.2 letters of vision. Among the 1,236 eyes with six years of follow-up data, the study authors reported that eyes received a mean of 2.9 injections in year six and gained +0.5 letters from baseline.

The investigators found that the number of injections decreased, and injection intervals increased year over year up to six years regardless of baseline VA initiation. In year one, the average injection interval was 10-weeks. This increased to 13.2 weeks in year two and then plateaued in years three to six at 12.6, 12.3, 12.2, and 12.3 weeks, respectively.

The greatest improvement in VA from baseline was observed in eyes that received five or more injections each year. At the end of follow-up, researchers reported that eyes with good baseline vision (> 20/25) lost vision, while eyes with worse baseline vision (< 20/25) gained vision. Additionally, the research revealed that worse visual acuity outcomes were correlated with patients of Hispanic ethnicity, Medicaid insurance and older age.

“This study provides valuable insight into understanding factors that affect routine treatment of DME and associated clinical outcomes. Real-world patients with DME receive much fewer anti-VEGF injections in clinical practice than those in clinical trials that established the efficacy of anti-VEGF agents for DME,” the study authors noted in their Ophthalmology Retina paper.

“This is a potential concern as maximum visual outcomes may not be achieved with suboptimal dosing. Furthermore, this study highlights the importance of considering individual patient characteristics in the managing and treating eyes with DME,” they concluded. “Future studies are warranted to understand how the DME treatment landscape is changing with the advent of novel treatment options.”