EFFICACY AND FREQUENCY OF INTRAVITREAL AFLIBERCEPT VERSUS BEVACIZUMAB FOR MACULAR EDEMA SECONDARY TO CENTRAL RETINAL VEIN OCCLUSION

The role of ATP in sleep-wake regulation: In adenosine-dependent and -independent manner

ATP plays a crucial role as an energy currency in the body's various physiological functions, including the regulation of the sleep-wake cycle. Evidence from genetics and pharmacology demonstrates a strong association between ATP metabolism and sleep. With the advent of new technologies such as optogenetics, genetically encoded biosensors, and novel ATP detection methods, the dynamic changes in ATP levels between different sleep states have been further uncovered. The classic mechanism for regulating sleep by ATP involves its conversion to adenosine, which increases sleep pressure when accumulated extracellularly. However, emerging evidence suggests that ATP can directly bind to P2 receptors and influence sleep-wake regulation through both adenosine-dependent and independent pathways. The outcome depends on the brain region where ATP acts and the expression type of P2 receptors. This review summarizes the experimental evidence on the relationship between ATP levels and changes in sleep states and outlines the mechanisms by which ATP is involved in regulating the sleep-wake cycle through both adenosine-dependent and independent pathways. Hopefully, this review will provide a comprehensive understanding of the current research basis and progress in this field and promote further investigations into the specific mechanisms of ATP in regulating sleep.

Intravitreal Ziv-Aflibercept versus Bevacizumab for Naïve Central Retinal Vein Occlusion with Macular Edema: An Interim Analysis of a Randomized Non-Inferiority Trial

Purpose

To compare the efficacy of intravitreal ziv-aflibercept (IVZ) and bevacizumab (IVB) injections for the treatment of macular edema secondary to central retinal vein occlusion.

Methods

Participants were randomly assigned 1:1 to receive 3 monthly IVZ (1.25 mg/0.05 mL) or IVB (1.25 mg/0.05 mL) followed by the pro-re-nata protocol for persistent or recurrent macular edema. The primary outcomes were best-corrected visual acuity and central subfield thickness. An interim analysis was planned when half of the participants completed the follow-up.

Results

Twenty-four participants were recruited. At 6 months, mean best-corrected visual acuity in the IVB and IVZ groups improved from 1.23 ± 0.64 to 0.76 ± 0.56 logMAR (p = 0.003) and from 1.13 ± 0.59 to 0.53 ± 0.26 logMAR (p = 0.003), respectively. The percentage of visual improvement and reduction in central subfield thickness in the IVZ group were insignificantly better than those in the IVB group (44.41 ± 26.72 vs 39.64 ± 24.22%; p = 0.65) and (51.94 ± 20.35 vs 45.78 ± 24.71%; p = 0.51), respectively. Although the mean number of injections was lower in the IVZ group (4.55 ± 1.29 vs 4.82 ±1.33), the difference was not statistically significant (p = 0.68). No ocular or systemic adverse events were observed.

Conclusion

The interim analysis demonstrated that the visual and anatomical results of IVZ were insignificantly better than those of IVB at 6 months of follow-up. The results also showed that IVZ was non-inferior to IVB for anatomical improvement but inconclusive for visual improvement.

Clinical Trial Registration

(identifier: TCTR20191205008).

[Intravitreal injection at IOTA-teaching hospital about 201 patients]

INTRODUCTION

Intravitreal injections (IVT) of a drug aim to rapidly obtain effective concentrations greater than those that would be obtained by a periocular or intravenous injection. The objective of the present study is to demonstrate the contribution of IVT in the treatment of pathologies of the posterior segment of the eye.

METHODOLOGY

We conducted a 21-month ambidirectional observational study from January 1, 2020, to September 30, 2021. We included by nonprobability sampling all consenting patients admitted for IVT at IOTA Teaching Hospital.

RESULTS

During our study, 201 patients were collected out of 30 739 patients seen in consultation. The hospital frequency of IVT was 0.65%. There were 111 women and 90 men. The M/F ratio was 0.82. The number of patients who received IVT antibiotics was 135. Anti-VEGF was injected in 64 patients. Two patients received IVT corticosteroids. Complications frequently encountered were pain at upon injection (94.03%), IOP spike (11.94%) and cataract (7.46%). In our sample, we observed an improvement in visual acuity in 56.21% of cases and a reduction in macular edema in 45.16% of cases.

DISCUSSION

The contribution of IVT in the treatment of vitreoretinal diseases is extraordinary. Rigorous observation of aseptic technique and good practices protects against infectious complications.

CONCLUSION

IVT has allowed us to effectively treat various diseases of the vitreous and retina. IVT is a simple procedure, but it must be performed with the same aseptic technique as surgical procedures.

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.

Real-world treatment intensities and pathways of macular edema following retinal vein occlusion in Korea from Common Data Model in ophthalmology

Despite many studies, optimal treatment sequences or intervals are still questionable in retinal vein occlusion (RVO) macular edema. The aim of this study was to examine the real-world treatment patterns of RVO macular edema. A retrospective analysis of the Observational Medical Outcomes Partnership Common Data Model, a distributed research network, of four large tertiary referral centers (n = 9,202,032) identified 3286 eligible. We visualized treatment pathways (prescription volume and treatment sequence) with sunburst and Sankey diagrams. We calculated the average number of intravitreal injections per patient in the first and second years to evaluate the treatment intensities. Bevacizumab was the most popular first-line drug (80.9%), followed by triamcinolone (15.1%) and dexamethasone (2.28%). Triamcinolone was the most popular drug (8.88%), followed by dexamethasone (6.08%) in patients who began treatment with anti-vascular endothelial growth factor (VEGF) agents. The average number of all intravitreal injections per person decreased in the second year compared with the first year. The average number of injections per person in the first year increased throughout the study. Bevacizumab was the most popular first-line drug and steroids were considered the most common as second-line drugs in patients first treated with anti-VEGF agents. Intensive treatment patterns may cause an increase in intravitreal injections.

Comparison of Intravitreal Bevacizumab and Aflibercept Injections for Central Serous Chorioretinopathy

Purpose: We examined differences in the treatment effects of intravitreal bevacizumab injections and intravitreal aflibercept injections in patients with central serous chorioretinopathy. Methods: This retrospective analysis included 51 eyes of 49 patients who received intravitreal anti-vascular endothelial growth factor agent injections after initial diagnosis with central serous chorioretinopathy. The patients were divided into two groups: one received an intravitreal bevacizumab injection, and another one received an intravitreal aflibercept injection. Patients with no reaction to treatment or a worsened condition, received repeat treatment with the same therapy. After treatment, patients were monitored for >3 months. Data were collected regarding best- corrected visual acuity (BCVA), subfoveal choroidal thickness, injection number, and treatment duration. Results: Both intravitreal bevacizumab injections and intravitreal aflibercept injections led to significant differences in BCVA (p < 0.0001, p = 0.001) and subfoveal choroidal thickness (p < 0.0001, p = 0.011), compared between before and after treatment. However, no differences between groups were observed in mean change of BCVA or subfoveal choroidal thickness. In addition, there were no differences between groups in injection number and treatment duration. Conclusions: In patients with central serous chorioretinopathy, both intravitreal bevacizumab injections and intravitreal aflibercept injections are effective treatment methods. There were no differences between the two medicines in terms of functional and anatomical recovery, or the injection number and treatment duration.

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.

Use of Anti-VEGF Drugs in Retinal Vein Occlusions

Retinal vein occlusion (RVO) is one of the most prevalent causes of visual loss in the Western World. Its pathogenesis is still not completely known. Chronic macular edema and ischemia compromise the functional and anatomical status of the retina. Antivascular endothelial growth factor (anti-VEGF) injections have demonstrated better results than other previous options, including observation or laser therapy. This narrative review aims to analyze the current aspects related to these drugs.

A treat and extend protocol with Aflibercept for cystoid macular oedema secondary to central retinal vein occlusion - an 18-month prospective cohort study

Background

To evaluate the safety and efficacy of a treat-and-extend protocol of aflibercept for cystoid macular oedema (CMO) secondary to central retinal vein occlusion (CRVO).

Methods

Twenty patients with CMO secondary to CRVO were included in this prospective cohort study. After 3 loading 4-weekly injections, treatment intervals were increased by 2 weeks if there was no clinical activity, to a maximum of 12 weeks. If clinical activity recurred or persisted, the interval between injections was shortened by 2 weeks, to a minimum of 4 weeks. Main outcome measures were change in visual acuity and the proportion of patients gaining 15 or more Early Treatment of Diabetic Retinopathy Study (ETDRS) letters from baseline at 6, 12 and 18 months.

Results

Mean BCVA gain from baseline was 19.7 ± 13.8, 22.2 ± 13.9 and 21.9 ± 15.8 ETDRS letters at 6, 12 and 18 months, respectively. Sixty-five percent of patients gained 15 or more ETDRS letters at 6 months, increasing to 70.6% at 12 and 18 months. Patients received 5.0 [4.0 to 6.0], 8.5 [8.0 to 10.3] and 11.0 [9.0 to 12.5] injections by 6, 12 and 18 months, respectively.

Conclusions

The visual outcomes achieved with a treat-and-extend protocol in this study were similar to the pivotal trials of aflibercept for CMO secondary to CRVO, which used monthly and then as-needed protocols.

Trial registration

Australian and New Zealand Clinical Trials Registry, registration number ACTRN12615000417583, 01/05/2015.

A treat and extend protocol with Aflibercept for cystoid macular oedema secondary to central retinal vein occlusion - an 18-month prospective cohort study

BACKGROUND

To evaluate the safety and efficacy of a treat-and-extend protocol of aflibercept for cystoid macular oedema (CMO) secondary to central retinal vein occlusion (CRVO).

METHODS

Twenty patients with CMO secondary to CRVO were included in this prospective cohort study. After 3 loading 4-weekly injections, treatment intervals were increased by 2 weeks if there was no clinical activity, to a maximum of 12 weeks. If clinical activity recurred or persisted, the interval between injections was shortened by 2 weeks, to a minimum of 4 weeks. Main outcome measures were change in visual acuity and the proportion of patients gaining 15 or more Early Treatment of Diabetic Retinopathy Study (ETDRS) letters from baseline at 6, 12 and 18 months.

RESULTS

Mean BCVA gain from baseline was 19.7 ± 13.8, 22.2 ± 13.9 and 21.9 ± 15.8 ETDRS letters at 6, 12 and 18 months, respectively. Sixty-five percent of patients gained 15 or more ETDRS letters at 6 months, increasing to 70.6% at 12 and 18 months. Patients received 5.0 [4.0 to 6.0], 8.5 [8.0 to 10.3] and 11.0 [9.0 to 12.5] injections by 6, 12 and 18 months, respectively.

CONCLUSIONS

The visual outcomes achieved with a treat-and-extend protocol in this study were similar to the pivotal trials of aflibercept for CMO secondary to CRVO, which used monthly and then as-needed protocols.

TRIAL REGISTRATION

Australian and New Zealand Clinical Trials Registry, registration number ACTRN12615000417583, 01/05/2015.

Simultaneous intravitreal dexamethasone and aflibercept for refractory macular edema secondary to retinal vein occlusion

PURPOSE

To assess the functional and anatomical outcomes of concurrent administration of aflibercept injection and dexamethasone (DEX) implant in patients with macular edema (ME) secondary to retinal vein occlusion (RVO), refractory to each of the two drugs previously administered as monotherapy. Secondary outcomes included the number of retreatments required in a 12-month follow-up and safety.

METHODS

This is a prospective, interventional case series of consecutive patients with refractory ME secondary to RVO, followed over a year. One injection of aflibercept was followed by a DEX implant on the same day; retreatment was driven by the persistence of ME on SD-OCT at least 4 months after the previous combined therapy. Central retinal thickness (CRT), best-corrected visual acuity (BCVA), and intraocular pressure (IOP) were collected at 1 month and then every 2 months until the end of follow-up.

RESULTS

Thirty eyes of 30 Caucasian patients were enrolled; mean duration of RVO before the first combined treatment was 25 ± 5 months (range 11 ± 30). Baseline BCVA was 0.73 ± 0.5 LogMAR, with no significant changes at 12 months (0.77 ± 0.51 μm, p = 0.2). Baseline CRT was 578.3 ± 161 μm, reducing to 352.5 ± 81 μm at 12 months (p = 0.003). Thirteen eyes (43.3%) required a second treatment. Twenty eyes (66.6%) showed no ME at the end of follow-up. One patient (3.3%) required topical IOP-lowering therapy during the study.

CONCLUSION

In eyes with ME secondary to RVO unresponsive to either aflibercept or DEX administered singularly, a combination therapy with simultaneous administration of aflibercept and DEX was effective in resolving ME, despite the absence of visual improvement. Earlier combined treatment in the course of the disease might lead to better functional outcomes.

Effect of funding source on reporting bias in studies of intravitreal anti-vascular endothelial growth factor therapy for retinal vein occlusion

PURPOSE

To examine the relationship between industry funding and outcome reporting bias in high-quality studies investigating the use of intravitreal anti-vascular endothelial growth factor (VEGF) agents for patients with macular oedema secondary to branch or central retinal vein occlusion (RVO).

METHODS

This systematic review in PubMed and Ovid MEDLINE examined all randomized clinical trials and meta-analyses published in journals with impact factor of ≥2 that investigated effectiveness of intravitreal anti-VEGF therapy in patients with RVO. The main outcome measure was correspondence between statistical outcome and abstract conclusion wording.

RESULTS

Forty-five studies met inclusion criteria; 38 (84%) showed correspondence between outcome and abstract conclusion without difference between industry-funded and nonindustry-funded publications (p = 0.39) or between publications in journals with impact factor ≥3 versus <3 (p = 0.96).

CONCLUSION

In high-quality studies of intravitreal anti-VEGF therapy for RVO, neither industry funding nor journal impact factor affected the rate of outcome reporting bias.

Comparative efficacy of bevacizumab, ranibizumab, and aflibercept for treatment of macular edema secondary to retinal vein occlusion: a systematic review and network meta-analysis

INTRODUCTION

Anti-vascular endothelial growth factor (VEGF) therapy has become the most commonly used treatment for macular edema secondary to retinal vein occlusion (RVO). Although its superior efficacy as compared to other interventions has been proven, there is a lack of evidence for relative efficacy among anti-VEGF drugs. Areas covered: This work systematically reviewed and compared the efficacy of intravitreal bevacizumab, ranibizumab, and aflibercept for treating macular edema due to RVO. PubMed, EMBASE, and the Cochrane Library were searched from their inception until October 2017. Eleven randomized controlled trials (18 articles; 1830 adult patients) were identified. The proportion of patients who gained at least 15 letters in best-corrected visual acuity (BCVA), mean change from baseline in BCVA, and mean change from baseline in central macular thickness (CMT) were reported and these efficacy outcomes at 6 months were analyzed in network meta-analysis. Expert commentary: Apparently, bevacizumab, ranibizumab, and aflibercept were significantly superior to sham injection in terms of BCVA improvement and CMT reduction and had good safety profiles. However, there were no statistically significant differences in any outcomes among anti-VEGF drugs. In selecting an anti-VEGF drug for individual patients, other factors including affordability, drug availability, and patient characteristics should be considered.