Outcomes of switching treatment to aflibercept in patients with macular oedema secondary to central retinal vein occlusion refractory to ranibizumab

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.

Retinal Vascular Resistance Significantly Correlates With Visual Acuity After 1 Year of Anti-VEGF Therapy in Central Retinal Vein Occlusion

Purpose

To investigate whether the resistivity of all retinal vessels, termed total capillary resistance (TCR), after anti-vascular endothelial growth factor (VEGF) treatment was correlated with the outcomes of patients with macular edema secondary to central retinal vein occlusion (CRVO).

Methods

In total, 67 patients with nonischemic CRVO were enrolled in this retrospective observational case series. In each patient, we examined visual acuity; central retinal thickness (CRT); mean blur rate (MBR), which represents retinal blood flow velocity; and TCR. MBR and TCR were measured by laser speckle flowgraphy.

Results

During the 1-year follow-up period, nine of 67 eyes (13.4%) converted to the ischemic type (converted group), whereas 58 eyes (86.6%) remained unchanged (nonischemic group). Mean CRT significantly decreased in all groups; however, the mean visual acuity significantly improved only in the nonischemic group. Mean MBR significantly increased in the nonischemic group but remained unchanged in the converted group. Mean TCR was significantly reduced in the nonischemic group but remained unchanged in the converted group. Multiple linear regression analysis revealed that MBR and TCR were the independent factors with the strongest and second strongest correlations with visual acuity after treatment, respectively.

Conclusions

These findings suggest that measurements of the independent factors MBR and TCR are useful for evaluating anti-VEGF treatments in patients with CRVO.

Translational Relevance

Development of clinically relevant technologies.

Intravitreal ranibizumab versus aflibercept versus bevacizumab for macular oedema due to central retinal vein occlusion: the LEAVO non-inferiority three-arm RCT

BACKGROUND

Licensed ranibizumab (0.5 mg/0.05 ml Lucentis®; Novartis International AG, Basel, Switzerland) and aflibercept (2 mg/0.05 ml Eylea®; Bayer AG, Leverkusen, Germany) and unlicensed bevacizumab (1.25 mg/0.05 ml Avastin®; F. Hoffmann-La Roche AG, Basel, Switzerland) are used to treat macula oedema due to central retinal vein occlusion, but their relative clinical effectiveness, cost-effectiveness and impact on the UK NHS and Personal Social Services have never been directly compared over the typical disease treatment period.

OBJECTIVE

The objective was to compare the clinical effectiveness and cost-effectiveness of three intravitreal antivascular endothelial growth factor agents for the management of macula oedema due to central retinal vein occlusion.

DESIGN

This was a three-arm, double-masked, randomised controlled non-inferiority trial.

SETTING

The trial was set in 44 UK NHS ophthalmology departments, between 2014 and 2018.

PARTICIPANTS

A total of 463 patients with visual impairment due to macula oedema secondary to central retinal vein occlusion were included in the trial.

INTERVENTIONS

The participants were treated with repeated intravitreal injections of ranibizumab (n = 155), aflibercept (n = 154) or bevacizumab (n = 154).

MAIN OUTCOME MEASURES

The primary outcome was an increase in the best corrected visual acuity letter score from baseline to 100 weeks in the trial eye. The null hypothesis that aflibercept and bevacizumab are each inferior to ranibizumab was tested with a non-inferiority margin of -5 visual acuity letters over 100 weeks. Secondary outcomes included additional visual acuity, and imaging outcomes, Visual Function Questionnaire-25, EuroQol-5 Dimensions with and without a vision bolt-on, and drug side effects. Cost-effectiveness was estimated using treatment costs and Visual Function Questionnaire-Utility Index to measure quality-adjusted life-years.

RESULTS

The adjusted mean changes at 100 weeks in the best corrected visual acuity letter scores were as follows - ranibizumab, 12.5 letters (standard deviation 21.1 letters); aflibercept, 15.1 letters (standard deviation 18.7 letters); and bevacizumab, 9.8 letters (standard deviation 21.4 letters). Aflibercept was non-inferior to ranibizumab in the intention-to-treat population (adjusted mean best corrected visual acuity difference 2.23 letters, 95% confidence interval -2.17 to 6.63 letters; p = 0.0006), but not superior. The study was unable to demonstrate that bevacizumab was non-inferior to ranibizumab in the intention-to-treat population (adjusted mean best corrected visual acuity difference -1.73 letters, 95% confidence interval -6.12 to 2.67 letters; p = 0.071). A post hoc analysis was unable to demonstrate that bevacizumab was non-inferior to aflibercept in the intention-to-treat population (adjusted mean best corrected visual acuity difference was -3.96 letters, 95% confidence interval -8.34 to 0.42 letters; p = 0.32). All per-protocol population results were the same. Fewer injections were required with aflibercept (10.0) than with ranibizumab (11.8) (difference in means -1.8, 95% confidence interval -2.9 to -0.8). A post hoc analysis showed that more bevacizumab than aflibercept injections were required (difference in means 1.6, 95% confidence interval 0.5 to 2.7). There were no new safety concerns. The model- and trial-based cost-effectiveness analyses estimated that bevacizumab was the most cost-effective treatment at a threshold of £20,000-30,000 per quality-adjusted life-year.

LIMITATIONS

The comparison of aflibercept and bevacizumab was a post hoc analysis.

CONCLUSION

The study showed aflibercept to be non-inferior to ranibizumab. However, the possibility that bevacizumab is worse than ranibizumab and aflibercept by 5 visual acuity letters cannot be ruled out. Bevacizumab is an economically attractive treatment alternative and would lead to substantial cost savings to the NHS and other health-care systems. However, uncertainty about its relative effectiveness should be discussed comprehensively with patients, their representatives and funders before treatment is considered.

FUTURE WORK

To obtain extensive patient feedback and discuss with all stakeholders future bevacizumab NHS use.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN13623634.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 38. See the NIHR Journals Library website for further project information.

Real-World Results of Switching Treatment from Ranibizumab to Aflibercept in Macular Oedema Secondary to Branch Retinal Vein Occlusion

Introduction

To investigate treatment outcomes after switching from ranibizumab to aflibercept intravitreal injections in patients with macular oedema (MO) secondary to branch retinal vein occlusion (BRVO).

Methods

Eligible patients with refractory MO secondary to BRVO, post treatment with a minimum of three intravitreal injections of ranibizumab at 4-weekly intervals were recruited. Suboptimal or non-responders were defined as patients who had persistent intraretinal fluid (< 75% decrease from baseline) despite a minimum of three consecutive injections. These patients were switched to aflibercept injections on an as-needed basis. The primary study outcomes assessed trends in best-corrected distance visual acuity (BCVA) and central retinal thickness (CRT). To compare means of BCVA and CRT, a paired t test two-tailed with a level of significance set at 0.05 was used. Pearson correlation coefficient was also applied to demonstrate correlation. Participants were followed up for a period of 24 weeks after switching.

Results

Thirty-eight eyes of 38 patients were included in the study. Patients had an average of 8.37 ranibizumab intravitreal injections over a mean period of 12 months presenting suboptimal or no response. A significant decrease of mean CRT from 388.63 ± 93.4 μm to 290.29 ± 93.5 μm (p < 0.001) and an improvement in mean BCVA from logMAR 0.66 ± 0.38 to logMAR 0.57 ± 0.27 (p = 0.025) was achieved after an average of 2.27 aflibercept injections.

Conclusions

Given the spectrum of therapies available to date for the management of MO secondary to BRVO, aflibercept appears to be an effective treatment option in cases refractory to ranibizumab. This study based on a small cohort of patients indicates that satisfactory results on retinal anatomy and visual outcomes can be accomplished with a smaller number of injections. Larger-scale studies are needed to extrapolate these promising results.

Anti-VEGF treatment of macular edema associated with retinal vein occlusion: patterns of use and effectiveness in clinical practice (ECHO study report 2)

Purpose

To evaluate the efficacy, safety, and injection frequency of vascular endothelial growth factor (VEGF) antagonists in the treatment of macular edema secondary to retinal vein occlusion (RVO) in clinical practice.

Patients and methods

A multicenter retrospective study of the medical records of 165 patients (95 branch RVO, 70 central RVO) treated with at least three anti-VEGF injections in the study eye was conducted. Available data collected for at least 6 months after the first injection included Snellen best-corrected visual acuity (BCVA), central retinal thickness (CRT) by time-domain optical coherence tomography (TD-OCT) or spectral-domain optical coherence tomography (SD-OCT), anti-VEGF injections, other treatments/procedures for RVO, and adverse events.

Results

At baseline prior to anti-VEGF treatment, mean BCVA was 20/80 Snellen equivalent and mean CRT was 499 μm. Mean number of anti-VEGF injections received was 7.1 during the first year, 5.4 during the second year, and 5.9 during the third year; 51.3% (842/1,641) of injections were ranibizumab, 44.1% (724/1,641) were bevacizumab, and 4.6% (75/1,641) were aflibercept. One in five patients received concomitant focal laser treatment. The percentage of patients achieving both BCVA of 20/40 or better and CRT ≤250 μm on TD-OCT or ≤300 μm on SD-OCT at the same visit (primary endpoint) was 26.1% (30/115) after the first anti-VEGF injection and ranged from 20.0% (7/35) to 36.7% (11/30) after the first 16 injections. After each anti-VEGF injection from the 1st to the 16th, <60% of patients achieved 20/40 or better BCVA and ≤70% of patients achieved CRT ≤250 μm on TD-OCT or ≤300 μm on SD-OCT. The most common treatment-related adverse event was blurry or cloudy vision.

Conclusion

In this real-world study, a mean of five to seven anti-VEGF injections was administered yearly, and the response to anti-VEGF therapy was suboptimal in many patients. Anti-VEGF therapy was well tolerated.