Efficacy and Safety of an Aflibercept Treat-and-Extend Regimen in Treatment-Naïve Patients with Macular Oedema Secondary to Central Retinal Vein Occlusion (CRVO): A Prospective 12-Month, Single-Arm, Multicentre Trial

CHANGE IN RETINAL PERFUSION WITH AFLIBERCEPT FOR CENTRAL RETINAL VEIN OCCLUSION: The Two-Year Prospective Observational HERMES Study

PURPOSE

To analyze retinal perfusion using ultrawide-field fluorescein angiography and optical coherence tomography angiography, in patients with central retinal vein occlusion treated by intravitreal injection of aflibercept.

METHODS

Single-arm, multicenter, prospective, observational study. Treatment-naive eyes with central retinal vein occlusion initiated therapy with aflibercept. Ultrawide-field fluorescein angiography with correction of projection distortion and optical coherence tomography angiography were performed at baseline (M0), M3, M12, and M24.

RESULTS

Fifty-six eyes were included. Visual acuity improved by 16 ETDRS letters at M12 ( P < 0.001), while mean central subfield thickness decreased from 801 µ m at M0 to 352 µ m at M12 ( P < 0.001). The ischemic index on ultrawide-field fluorescein angiography increased from 17% at M0 to 23% at M3, and to 36% at M24. Ischemic central retinal vein occlusion accounted for 18% at M0, 25% at M3, and 39% at M24 ( P < 0.05). Vascular leakage was only present in 21% of eyes at M12. The density of the superficial and deep capillary plexus remained stable, but the foveal avascular zone enlarged from 0.37 mm 2 at M0 to 0.61 mm 2 at M24 ( P = 0.02). No cases of reperfusion were observed. The mean number of injections at M12 was 7.0 ± 3.6.

CONCLUSION

Changes in retinal perfusion were characterized by worsening perfusion in the periphery, while macular capillaries maintained a generally stable density at M24, even in ischemic central retinal vein occlusion. These findings support the need for regular monitoring of peripheral retinal perfusion in treated patients to detect silent progression of nonperfusion, which may lead to neovascular complications, while visual acuity is maintained over the long term, likely due to the preserved macular capillary density.

Risk Factors and Treatment Strategy for Retinal Vascular Occlusive Diseases

Retinal occlusive diseases are common diseases that can lead to visual impairment. Retinal artery occlusion and retinal vein occlusion are included in the clinical entity, but they have quite different pathophysiologies. Retinal artery occlusion is an emergent eye disorder. Retinal artery occlusion is mainly caused by thromboembolism, which frequently occurs in conjunction with life-threatening stroke and cardiovascular diseases. Therefore, prompt examinations and interventions for systemic vascular diseases are often necessary for these patients. Retinal vein occlusion is characterized by retinal hemorrhage and ischemia, which may impair visual function via several complications such as macular edema, macular ischemia, vitreous hemorrhage, and neovascular glaucoma. Even though anti-vascular endothelial growth factor therapy is the current established first-line of treatment for retinal vein occlusion, several clinical studies have been performed to identify better treatment protocols and new therapeutic options. In this review, we summarize the current findings and advances in knowledge regarding retinal occlusive diseases, particularly focusing on recent studies, in order to provide an update for a better understanding of its pathogenesis.

Real-Life Efficacy of Bevacizumab Treatment for Macular Edema Secondary to Central Retinal Vein Occlusion according to Pro Re Nata or Treat-and-Extend Regimen in Eyes with or without Epiretinal Membrane

Purpose. To present real-life data of patients with macular edema (ME) secondary to central retinal vein occlusion (CRVO) treated with bevacizumab (BVZ); determine the possible influence of epiretinal membrane (ERM) on treatment efficacy; and compare treatment outcomes in a treat-and-extend regimen (TER) versus pro re nata (PRN). Methods. We carried out a retrospective analysis of 58 eyes (56 patients) with new-onset CRVO treated only with intravitreal bevacizumab according to TER or PRN. Outcome measures were best-corrected visual acuity (BCVA) and central retinal thickness (CRT) at baseline and 12 months after the first treatment, number of visits and injections, and presence of ERM confirmed by optical coherence tomography in the first 6 months. Results. At 12 months, the mean number of injections was 6.3 across all eyes, with significantly more injections given in TER ( $p<0.001$ ). Mean CRT improved from 627 μm to 359 μm ( $p<0.001$ ) in all eyes, with improvement noted in TER ( $p<0.001$ ), PRN ( $p<0.001$ ), ERM ( $p=0.003$ ), and non-ERM ( $p<0.001$ ) subgroups. The mean BCVA gain was +13.6 letters, and the mean BCVA improved from 0.81 to 0.54 LogMAR ( $p<0.001$ ) in all eyes. BCVA improvement from baseline was significant in TER ( $p<0.001$ ) and non-ERM ( $p<0.001$ ) but not in PRN ( $p=0.08$ ) or ERM ( $p=0.2$ ) subgroups. Seven eyes, all receiving PRN treatment, developed neovascularization. Conclusions. Intravitreal bevacizumab according to either PRN or TER resolved edema and stabilized vision in the first 12 months, with TER yielding significant visual improvement and avoiding neovascular complications. ERM had no influence on bevacizumab efficacy in reducing ME in CRVO during 12 months of treatment.

Treat-and-extend regimens of anti-vascular endothelial growth factor therapy for retinal vein occlusions: a systematic review and meta-analysis

OBJECTIVE

To investigate treat-and-extend (T&E) regimens of anti-vascular endothelial growth factor (anti-VEGF) therapy for the treatment of macular oedema secondary to retinal vein occlusions (RVOs).

METHODS

Ovid MEDLINE, Ovid EMBASE and CENTRAL were searched on 25 February 2021. Randomized controlled trials, cohort studies, case-control studies and case series were included. The primary outcome was the change in Early Treatment Diabetic Retinopathy Score (ETDRS) letters from baseline. Conversions from Snellen to ETDRS letters were performed utilizing a published protocol. Secondary outcomes included improvement in retinal thickness from baseline, number of anti-VEGF injections and frequency of adverse events. Outcomes were examined at 12 and 24 months. Certainty of evidence was assessed utilizing GRADE (Grading of Recommendations Assessments, Development and Evaluations) guidelines.

RESULTS

Seven hundred eighty-six eyes from 16 studies were included. Meta-analysis demonstrated a mean improvement of 15.7 (95% CI: 13.3-18.0) ETDRS letters at 12 months. Central retinal thickness improved 269.7 μm (95% CI: 233.64-305.90) at 12 months. Injections were performed 8.1 (95% CI: 7.4-8.7) and 13.1 (95% CI: 9.4-16.8) times at 12 and 24 months respectively. Adverse events were infrequent across all studies. Grading of Recommendations Assessments, Development and Evaluations (GRADE) certainty of evidence was very low across all outcomes.

CONCLUSIONS

The results support the viability of T&E regimens for the treatment of macular oedema secondary to RVOs.

A Review of Aflibercept Treatment for Macular Disease

Aflibercept is a fully human recombinant fusion protein that includes the second domain of human VEGF receptor 1 and the third domain of human VEGF receptor 2. Despite the important role played by VEGF in maintaining the physiological condition of the retina under normal conditions, dysregulation of VEGF can result in pathological alterations including hyperpermeability of the retinal capillaries and migration and proliferation of retinal endothelial cells. Over the years, a number of studies have evaluated the use of intravitreal aflibercept in different retinal diseases. In this review, we aim to summarize the scientific evidence and recommendations for use of intravitreal aflibercept in neovascular age-related macular degeneration, diabetic macular oedema, macular oedema associated with retinal vein occlusion, and myopic choroidal neovascularization.

Current Best Clinical Practices-Management of Retinal Vein Occlusion

Retinal vein occlusion (RVO) is the second most common cause of vision loss from retinal vascular diseases in adults in the United States. Visual loss arises as a result of a host of factors, including macular ischemia and macular edema. Primary antivascular endothelial growth factor therapy is the current standard of care, with level I evidence demonstrating sustained visual gains up to 2 years after treatment in both branch and central RVO. Prompt antivascular endothelial growth factor therapy is important because delays in treatment yield lesser visual gains. Steroid therapy also improves visual outcomes in RVO but with higher rates of adverse effects, including cataract formation and ocular hypertension. Although the treatment burden can be high, these drugs have collectively revolutionized treatment outcomes in this disease state, providing improved visual outcomes over previous laser therapies.