Relationship Between Macular Thickness and Visual Acuity in the Treatment of Diabetic Macular Edema With Anti-VEGF Therapy: Systematic Review

Anatomic biomarkers as potential endpoints in diabetic macular edema: A systematic literature review with identification of macular volume as a key surrogate for visual acuity

Optimization of diabetic macular edema (DME) treatment pathways can aid in the efficient introduction of new therapies that provide value to patients and healthcare systems. We performed a systematic literature review and multicorrelation analysis to identify and evaluate anatomic biomarkers as potential surrogate endpoints (SEs) for visual acuity (VA) in patients with DME. We performed EMBASE and MEDLINE searches to identify studies reporting on 4 priority biomarkers previously identified by clinical experts: hyperreflective foci, intraretinal cyst, macular volume (MV), and subretinal fluid. Endpoint and treatment effect correlation analyses were performed to establish correlation coefficients between MV and VA using Pearson's correlation. A total of 105 studies reported change from baseline data for VA, and at least 1 biomarker, with MV investigated most often (n = 70 studies). Data extracted from 55 studies focusing on the 6-mm zone for MV were used in statistical analyses. A moderate correlation was observed between MV and VA at the endpoint level (r = 0.58; p < 0.01); however, a corresponding treatment effect was not found (r = 0.32; p = 0.19). Our findings suggest MV's potential as an SE for VA in future clinical practice; however, the lack of a significant treatment effect warrants that these findings be interpreted cautiously. Further evidence and improvements in reporting the methods for collecting biomarker data are needed. Analysis of outliers and subanalyses by other optical coherence tomography measures could establish the most meaningful MV values correlating with VA.

Efficacy & safety of brolucizumab 6.0 mg versus 3.6 mg in diabetic macular edema

BACKGROUND

Management of Diabetic Macular edema (DME) requires repeated injections. Therefore newer Anti-VEGFs like Brolucizumab with longer durability have been introduced. We compared two different dosages of Brolucizumab, 6.0 mg and 3.6 mg, for their safety & efficacy in treatment of DME, in treatment naïve patients over 52 weeks.

METHOD

A prospective, pilot randomised controlled, single centre, double blinded, two arm comparative study was conducted between Dec 2022 to Apr 2024. The study recruited 82 patients of DME who were randomised into two groups of 41 patients each, one group to be treated with Brolucizumab 6.0 mg in 50 μL and the other to receive 3.6 mg in 30 μL. All patients received the first dose of Brolucizumab at 0 week and were then followed up at every 4 weeks for detailed ophthalmic and OCT macula examination. Those who met the pre-defined re-treatment criteria were re-injected with Brolucizumab, the dose being fixed for each group throughout the study. All patient receiving an injection were further followed up on Day 1, Day 7 and Day 28 to look for any adverse reactions. The efficacy parameters included change in best corrected visusal acuity (BCVA), contrast and central macular thickness (CMT) on Optical Coherence Tomography. The average number of injections recd in each group were also calculated.

RESULTS

The change in BCVA from baseline in 6.0 mg group was 0.54 LogMAR units and 3.6 mg group was 0.59 LogMAR units, which was not statistically significant. The reduction in CMT from baseline in 6.0 mg group was 133.2 µm (μ) and 3.6 mg group was 110.6 μ, which was not statistically significant. The improvement in contrast from baseline in 6.0 mg group was 0.74 and 3.6 mg group was 0.95, with p value of 0.0002. The re-injection interval was 14.21 weeks in 6.0 mg group and 15.56 weeks for 3.6 mg subgroup. The total number of adverse events in both groups were similar at 70 in 6.0 mg group and 47 in 3.6 mg group with only one grade 4 adverse event occurring in each group.

CONCLUSION

The results of present study show that the safety and efficacy of both doses of Brolucizumab, i.e. 6.0 mg and 3.6 mg, for treating diabetic macular edema is similar. Trial registration Study was registered with Clinical trials registry of India (CTRI ref no. CTRI/2023/06/054105), registered on 14 Nov 2022.

Diabetic Disease of the Eye in Canada: Consensus Statements from a Retina Specialist Working Group

Despite advances in systemic care, diabetic disease of the eye (DDE) remains the leading cause of blindness worldwide. There is a critical gap of up-to-date, evidence-based guidance for ophthalmologists in Canada that includes evidence from recent randomized controlled trials. Previous guidance has not always given special consideration to applying treatments and managing DDE in the context of the healthcare system. This consensus statement aims to assist practitioners in the field by providing a spectrum of acceptable opinions on DDE treatment and management from recognized experts in the field. In compiling evidence and generating consensus, a working group of retinal specialists in Canada addressed clinical questions surrounding the four themes of disease, patient, management, and collaboration. The working group reviewed literature representing the highest level of evidence on DDE and shared their opinions on topics surrounding the epidemiology and pathophysiology of diabetic retinopathy and diabetic macular edema; diagnosis and monitoring; considerations around diabetes medication use; strategic considerations for management given systemic comorbidities, ocular comorbidities, and pregnancy; treatment goals and modalities for diabetic macular edema, non-proliferative and proliferative diabetic retinopathy, and retinal detachment; and interdisciplinary collaboration. Ultimately, this work highlighted that the retinal examination in DDE not only informs the treating ophthalmologist but can serve as a global index for disease progression across many tissues of the body. It highlighted further that DDE can be treated regardless of diabetic control, that a systemic approach to patient care will result in the best health outcomes, and prevention of visual complications requires a multidisciplinary management approach. Ophthalmologists must tailor their clinical approach to the needs and circumstances of individual patients and work within the realities of their healthcare setting.