Intravitreal Anti-Vascular Endothelial Growth Factor Therapy for Diabetic Macular Edema in Clinical Practice of Single Center: Three-Year Outcomes

Real-World Outcomes of Anti-VEGF Therapy in Diabetic Macular Oedema: Barriers to Treatment Success and Implications for Low/Lower-Middle-Income Countries

Diabetic macular oedema (DMO) is the leading cause of vision loss associated with diabetic eye disease. The exponential increase in the diabetic population and thus, of DMO is an impetus for optimizing the management of DMO. One major challenge in DMO management is the discrepancy between treatment outcomes seen in clinical trials and the real world. Contrary to the homogeneity, better patient motivation and shorter study durations seen in randomised control trials, routine clinical practice is fraught with more diverse populations, undertreatment and variable compliance with long-term therapy. Under both circumstances, this review aims to compare efficacy outcomes and adverse events of DMO therapies within the scope of anti-vascular endothelial growth factor (anti-VEGF) medications, specifically the commonly used ones-bevacizumab, ranibizumab and aflibercept. Impediments and methods to achieve better treatment outcomes in the real world will be addressed to achieve better outcomes. Low- to lower-middle-income countries are faced with even more barriers which range from paucity of data on epidemiology and treatment response to scarce human and financial resources to poorer national level attention and then basic issues like transportation. Additionally, to address the lack of a global consensus in DMO treatment, this review generates and recommends, for clinical and research purposes, an up-to-date consensus algorithm for DMO management universally. Underpinned by results from clinical trials and recent guidelines, this therapeutic flowchart can be utilised in various resource settings including low- and lower-middle-income countries where affordability is a major deterrent to treatment access.

Real-World Evidence in the Management of Diabetic Macular Edema with Intravitreal Anti-VEGFs in Asia: A Systematic Literature Review

Purpose

To evaluate the visual outcomes and safety profile of intravitreal anti-vascular endothelial growth factor (anti-VEGF) therapy in the treatment of diabetic macular edema (DME) in real-world studies in Asian countries.

Methods

A systematic review of electronic literature databases (Embase, Medline, and the Cochrane Library from January 1, 2010, to March 16, 2021) was conducted to identify observational studies that reported clinical and safety outcomes of anti-VEGF treatments for DME in Asia. We analyzed baseline patient characteristics, treatment patterns, mean number of injections, best-corrected visual acuity (BCVA), retinal thickness, and safety outcomes.

Results

Seventy-one studies were included in this review. Most studies reported treatment of DME with ranibizumab (n = 33), followed by aflibercept (n = 13), bevacizumab (n = 28), and conbercept (n = 9). At 12 months, the cumulative mean number of injections for ranibizumab, aflibercept, and conbercept was 5.2, 4.6, and 6, respectively. At the 12-month follow-up, the cumulative mean BCVA gain was 6.8 letters (ranibizumab), 4.6 letters (aflibercept), 4.9 letters (bevacizumab), and 8.3 letters (conbercept). The cumulative mean reduction in retinal thickness at 12 months was 116.9 μm (ranibizumab), 105.9 μm (aflibercept), 81.7 μm (bevacizumab), and 135.2 μm (conbercept). A strong positive correlation (r = 0.78) was observed between mean number of injections and change in BCVA at 12 months. A moderate positive correlation (r = 0.54) was observed between mean number of injections and mean reduction in retinal thickness at 12 months. A weak positive correlation was observed between baseline retinal thickness and visual acuity at 12 months. Baseline BCVA and mean number of injections were predictors of BCVA at 12 months.

Conclusion

All anti-VEGFs were effective in the treatment of DME in Asia. The data suggest that a greater number of anti-VEGF injections was associated with better improvement in BCVA and moderate reduction in retinal thickness at the 1-year follow-up.

Anti-vascular endothelial growth factor therapy in diabetic macular edema: real-life outcomes from a multicenter study in Turkey over 36 months

PURPOSE

This study aimed to report the visual and anatomical outcomes of intravitreal anti-VEGF treatment for diabetic macular edema (DME) in a real-world clinical setting from Turkey over 36 months.

METHODS

This is a retrospective, multicenter (7 sites) study. The medical records of 1072 eyes (both previously treated and naive eyes) of 706 consecutive patients with visual impairment due to center-involving DME treated with intravitreal anti-VEGF injections between April 2007 and February 2017 were reviewed. The eyes were divided into mutually exclusive three groups based on the duration of follow-up (12, 24, or 36 months). Primary outcome measures were changes in visual acuity (VA) and central macular thickness (CMT) from baseline to final visit in each cohort, frequency of visits and intravitreal anti-VEGF injections. As secondary endpoints, VA outcomes were assessed in subgroups stratified by baseline VA [<70 ETDRS letters and ≥70 ETDRS letters] and loading dose status of anti-VEGF injections.

RESULTS

VA increased by a mean of 8.2 letters (12-month cohort, p < 0.001), 5.3 letters (24-month cohort, p < 0.001), and 4.4 letters (36-month cohort, p = 0.017) at final visits. The eyes with <70 VA letters achieved more significant VA improvement at final visits in all cohorts compared with eyes with >70 VA letters (p < 0.001). The mean decreases in CMT from baseline to last visits at 12-, 24-, and 36- month cohorts were -100.5 µm, -107.7 µm, and -114.3 µm, respectively (p < 0.001). The mean number of injections given were 4.6, 2.3, and 1.8 during years 1 to 3, respectively. Patients who received loading dose showed greater VA gains than those who did not in all follow-up cohorts.

CONCLUSION

Our study revealed that anti-VEGF treatment improved VA and CMT over a follow-up of 36 months. Although these real-life VA outcomes following anti-VEGF therapy for DME were similar to other real-life studies, they were inferior to those noted in randomized controlled trials, mainly due to undertreatment.

TITLE: THREE-YEAR TREATMENT OUTCOMES OF AFLIBERCEPT VERSUS RANIBIZUMAB FOR DIABETIC MACULAR EDEMA: DATA FROM THE FIGHT RETINAL BLINDNESS! REGISTRY

PURPOSE

Compare the three-year outcomes of ranibizumab versus aflibercept in eyes with DME in daily practice.

METHODS

This was a retrospective analysis of naive DME eyes starting intravitreal injections of ranibizumab (0.5mg) or aflibercept (2mg) from 1 January 2013 to 31 December 2017 that were collected in the Fight Retinal Blindness! registry.

RESULTS

We identified 534 eyes (ranibizumab - 267, aflibercept - 267) of 402 patients. The adjusted mean (95% CI) VA change of +1.3 (-0.1, 4.2) letters in the ranibizumab group and +2.4 (-0.2, 5.1) letters (P = 0.001) in the aflibercept group at 3 years was not clinically different. However, the adjusted mean CST change appeared to remain significantly different throughout the three-year period with higher reductions in favor of aflibercept (-87.8 [-108.3, -67.4] µm for ranibizumab vs. -114.4 [-134.4, -94.3] for aflibercept; P < 0.01). When baseline visual impairment was moderate (VA ≤68 ETDRS letters), we found a faster improvement in VA in eyes treated with aflibercept up until 18 months of treatment than eyes treated with ranibizumab, which then stayed similar until 36 months of treatment, while there was no apparent difference when baseline visual impairment was mild (VA ≥69 ETDRS letters). The rate of serious adverse events was low.

CONCLUSIONS

Aflibercept and ranibizumab were both effective and safe for DME over 3 years.

Ellipsoid Zone Integrity and Visual Acuity Changes during Diabetic Macular Edema Therapy: A Longitudinal Study

PURPOSE

Ellipsoid zone (EZ) integrity is identified as a potential biomarker for therapy surveillance and outcome prediction of visual acuity (VA). However, only a few studies report long-term results of over 1 year of clinical and anatomical changes in patients with diabetic macular edema (DME). This study is aimed at describing the long-term VA and anatomical outcomes in spectral domain optical coherence tomography (OCT) (relative ellipsoid zone reflectivity ratio, central macular thickness, and volume) in patients with DME treated with antivascular endothelial growth factor (anti-VEGF) therapy. Furthermore, we studied the correlation between EZ integrity and changes in visual acuity.

METHODS

71 eyes of 71 patients were included in this retrospective study. Clinical characteristics were reviewed yearly. OCT data were assessed at baseline and after 1, 3, and 5 years. EZ parameters were quantified automatically. OCT parameters and visual outcome were correlated and analyzed in multivariable regression models.

RESULTS

EZ reflectivity ratio correlated with functional outcome in DME patients from baseline to fifth year at all time points (for all p < 0.05). EZ reflectivity improved the most in the first year of treatment (0.68 to 0.75; p < 0.05) and declined gradually until year 5 of therapy (0.71; compared to baseline p > 0.05). Similarly, best VA was achieved after 1 year (0.40 logarithm of the minimum angle of resolution (logMAR) to 0.28 logMAR; p < 0.001) and declined gradually until year 5. Final VA in year 5 was comparable to baseline (0.45 logMAR, compared to baseline p > 0.05). Together with baseline VA, baseline EZ parameters did predict VA outcome after 1 year (p < 0.05). Concordantly, VA and EZ parameters from year 1 were associated with VA outcome in year 2.

CONCLUSION

This study described the long-term course of EZ changes during anti-VEGF treatment in DME patients. In addition, our results underlined the potential of EZ parameters as novel OCT biomarkers for prediction of VA outcomes during therapy.