Anti-vascular endothelial growth factor (anti-VEGF) nonresponders account for approximately half of patients with diabetic macular edema (DME), according to data from a real world investigation published in Clinical Ophthalmology. Despite receiving numerous injections and requiring frequent changes in therapy, anti-VEGF nonresponders experienced little to no significant improvement in their best visual activity (BVA) and central retinal thickness (CRT), the researchers report.
Researchers conducted a retrospective cohort study using electronic health records to identify adult patients with DME who received their first anti-VEGF injection between October 1, 2015, and September 30, 2016. The study aimed to understand the demographics, clinical characteristics, treatment patterns, and visual and anatomical responses of patients treated with anti-VEGF agents in 4 clinical sites in Ontario, Canada. Participants were followed for 18 months or more. After the first 3 monthly injections, they were classified as “anti-VEGF responders” or “anti-VEGF nonresponders” based on the reduction in central retinal thickness from the index date.
A total of 97 patients were eligible for inclusion in the study, but 11 were later excluded due to receiving less than 3 anti-VEGF injections during the study period. The mean age in the overall population at baseline was 64.8 years and 55.8% were 65 or older, and 61.6% were men. Type 1 diabetes was reported in 20% and type 2 in 80% of the overall population.
At year 1, the mean (SD) change in BVA from baseline was 12.8 (13.0) letters in the responder group compared with 3.2 (16.3) letters in the anti-VEGF nonresponder group. At 12 months, a gain of 15 letters or more was experienced by 36.7% of the responder group compared with 15.7% in the anti-VEGF nonresponder group.
At 18 months, 34.5% of the anti-VEGF responder group and 14.0% of the anti-VEGF nonresponder group had a 15 letter gain or better. Responders had a mean (SD) change in CRT of -160.4 (111.4) μm, whereas nonresponders had a mean (SD) change of -62.2 (98.6) μm. The changes in anti-VEGF therapy were lower for the responders (10.0%) compared with the non-responders (23.2%), but both groups received a similar mean number of injections (8.3).
The study is limited by its descriptive nature and small sample size of responders and nonresponders. There was also a lack of data on the type of anti-VEGF regimen administered.
“Our findings from the real-world sample indicated that more than 50% of the participants are non-responders to anti-VEGF therapy for DME, despite switching between different anti-VEGF agents. This outcome is not surprising given the complex pathophysiology of DME,” the researchers report.
Disclosure: This research was supported by AbbVie. Please see the original reference for a full list of disclosures.
Somani S, Koushan K, Shah-Manek B, et al. Characteristics and treatment patterns of patients with diabetic macular edema non-responsive to anti-vascular endothelial growth factor treatment in Ontario, Canada. Clin Ophthalmol. Published online July 17, 2023. doi:10.2147/OPTH.S399981