Intravitreal Bevacizumab in Central Retinal Vein Occlusion: 18-month Results of a Prospective Clinical Trial

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.

Patient-reported outcomes from a phase IV study of aflibercept in patients with refractory retinal vein occlusions

PURPOSE

To determine the patient-centered effectiveness of switching patients with persistent macular edema due to retinal vein occlusion (RVO) to aflibercept using the National Eye Institute Visual Function Questionnaire 25 (NEI-VFQ-25).

MATERIALS AND METHODS

Prospective study of eyes with persistent cystoid macular edema due to RVO despite regular treatment with bevacizumab or ranibizumab switched to aflibercept. Three loading doses of intravitreal aflibercept were administered every 4 weeks and thereafter every 8 weeks until week 48. Vision-related quality of life (VRQoL) using NEI-VFQ-25 was measured at baseline, 24 weeks, and 48 weeks following the switch. Baseline scores were compared to week 24 and 48 using paired t-test. Relationship between best-corrected visual acuity (BCVA) in the study eye and the NEI-VFQ-25 composite and subscale scores was investigated.

RESULTS

Eighteen patients with RVO were enrolled in the study with a mean age of 70.3 ± 8.6 years. The mean change in BCVA and central macular thickness (CMT) from baseline to 48 weeks was +20.6 ± 5.2 Early Treatment of Diabetic Retinopathy Score letters and -109.2 ± 82.8 µm, respectively. VRQoL improved significantly, with an increase of mean NEI-VFQ composite score of 11.5 ± 9.5; the corresponding improvements in near and distant activities were 13.3 ± 19.4 and 8.4 ± 10.4, respectively (P < 0.001 for both). Logistic regression analysis demonstrated that BCVA gain of >15 letters and CMT < 300 µm at the end of the study predicted a higher change in VFQ-25.

CONCLUSION

Switching eyes with persistent macular edema due to RVO to aflibercept resulted in significant improvement in visual function and patient satisfaction.

Intravitreal Injection of Anti-vascular Endothelial Growth Factor Agents for Ocular Vascular Diseases: Clinical Practice Guideline

PURPOSE

To provide the clinical recommendations for the administration of intravitreal anti-vascular endothelial growth factor (VEGF) drugs especially bavacizumab for ocular vascular diseases including diabetic macular edema, neovascular age-related macular degeneration, myopic choroidal neovascularization, retinal vein occlusion and central serous chorioretinopathy.

METHODS

Twenty clinical questions were developed by the guideline technical committee. Relevant websites and databases were searched to find out the pertinent clinical practice guidelines to answer the questions. The technical committee provided possible answers (scenarios) according to the available evidences for each question. All scenarios along with their levels of evidence and the supported articles were sent to the experts for external review. If the experts did not agree on any of the scenarios for one particular clinical question, the technical committee reviewed all scenarios and their pertinent evidences and made the necessary decision. After that, the experts were asked to score them again. All confirmed scenarios were gathered as the final recommendations.

RESULTS

All the experts agreed on at least one of the scenarios. The technical committee extracted the agreed scenario for each clinical question as the final recommendation. Finally, 56 recommendations were developed for the procedure of intravitreal anti-VEGF injection and their applications in the management of ocular vascular diseases.

CONCLUSION

The implementation of this guideline can standardize the management of the common ocular vascular diseases by intravitreal injection of anti-VEGF agents. It can lead to better policy-making and evidence-based clinical decision by ophthalmologists and optimal evidence based eye care for patients.

Comparison of treatment response to intravitreal injection of triamcinolone, bevacizumab and combined form in patients with central retinal vein occlusion: A randomized clinical trial

BACKGROUND

Central retinal vein occlusion (CRVO), is the second-most common disorder after diabetic retinopathy that threatens the vision related to retinal vessels. One of the main reasons of vision loss is CRVO in acute and chronic forms.

OBJECTIVE

The aim of this study was to investigate the response to intravitreal injection of triamcinolone, bevacizumab, and a combined form in patients with CRVO.

METHODS

This study was a double-blinded randomized clinical trial conducted on patients with CRVO who were referred to the ophthalmology clinic of Urmia Imam Khomeini Hospital from May 2015 to May 2016. In total, ninety patients were divided into three groups using random numbers table. The first group received intravitreal triamcinolone acetonide (IVT) for treatment of macular edema due to CRVO, the second group received intravitreal bevacizumab (IVB) and the third group received a combination of IVT and IVB. The best corrected visual acuity (BCVA) and central macular thickness (CMT) were recorded and analyzed using optical coherence tomography system.

RESULTS

In this study a total of 90 eyes were studied, 41 case (45.55%) were male and 49 cases (54.44%) were female. The mean age of patients was 68.41±8.32 years. The mean score of final visual acuity was 0.293±0.11 in the IVT group, 0.25±0.10 in the IVB group and 0.48±0.15 in the IVB+IVT group. The differences between groups considering final visual acuity was significant (p<0.001). The mean thickness of final macular was 383.33±97.70 micrometer in IVT group, 386.33±136.79 micrometers in IVB group and 307.33±110.79 micrometers in IVT+IVB group which were significant (p=0.014).

CONCLUSION

Using a combination of bevacizumab and triamcinolone in the treatment of central retinal vein occlusion compared with using each of them separately, had a better result and can be used as a solution in this disease.

TRIAL REGISTRATION

The trial was registered at the Thai Registry of Clinical Trials (http://www.clinicaltrials.in.th) with the TCTR ID: TCTR20170612005.

FUNDING

The authors received no financial support for the research, authorship, and/or publication of this article.

[Current approach and the role of laser photocoagulation in the treatment of retinal vein occlusions]

Despite the emergence of new approaches in the treatment of retinal vein thrombosis and post-thrombotic complications, namely, intravitreal pharmacotherapy and surgical treatment, laser photocoagulation continues to play a significant role in the management of patients with this pathology. Although the method of laser photocoagulation has been used for quite a long time, different views exist on its indications and execution in specific clinical situations. At that, not all opinions regarding the use of laser photocoagulation in thrombosis are based on convincing clinical studies. The aim of this work was to summarize current literature data on the use of laser photocoagulation in the integrated treatment of retinal vein occlusions and, also, to show which aspects of the treatment of thromboses can be considered well-established and reasonable and which remain a subject of debate.

RETINAL VEIN OCCLUSIONS, FROM BASICS TO THE LATEST TREATMENT

PURPOSE

To review the pathophysiology, diagnosis, and updated treatments of retinal vein occlusions (RVOs).

METHODS

A review of the literature was performed, focusing on the epidemiology, pathophysiology, diagnosis, and treatments (including both medical and surgical treatments) of RVO. Based on this review, a comprehensive overview was provided regarding the topic of RVO and focused on recent treatment updates.

RESULTS

Retinal vein occlusions have an age- and sex-standardized prevalence of 5.20 per 1,000 for any RVO, 4.42 per 1,000 for branch RVO, 0.80 per 1,000 for central RVO. Worldwide, an estimated 16.4 million adults are affected by RVOs, with 2.5 million affected by central RVO and 13.9 million affected by branch RVO. Retinal vein occlusion is recognized as an important cause of blindness and the diagnostic approaches and treatment options for RVO are reviewed and reported. The current treatment options including medical treatments (bevacizumab, ranibizumab, aflibercept, triamcinolone, and dexamethasone implants) and surgical alternatives were reviewed and reported with summaries on the corresponding strength of evidence.

CONCLUSION

Despite the understanding of this disease entity, challenges persist in the long-term treatment of RVO-related complications and visual loss. This review provided a detailed summary on the rationality and efficacy of recently developed treatment regimes and evaluated the potential benefit of combination therapy.

Outcomes of Patients Initially Treated with Intravitreal Bevacizumab for Central Retinal Vein Occlusion: Long-Term Follow-Up

BACKGROUND AND OBJECTIVE

To assess outcomes of visual acuity (VA) and central retinal thickness (RT) in patients with macular edema (ME) secondary to central retinal vein occlusion (CRVO) who were initially treated with bevacizumab and followed for up to four years.

STUDY DESIGN/MATERIALS AND METHODS

In this observational case series, 51 patients with non-ischemic and ischemic CRVO who had initial treatment with bevacizumab were included. Main outcome measures were VA and RT at one year, with follow-up of up to four years.

RESULTS

Mean VA improved from 20/214 at baseline to 20/107 at one year (p = 0.0009) and this improvement was maintained clinically at four years. RT decreased from 595 μm to 339 μm at one year (p = 0.0027) and this was maintained at four years.

CONCLUSION

Patients who received bevacizumab as initial therapy for ME from CRVO maintained VA and RT improvement for up to four years.

Three intravitreal bevacizumab versus two intravitreal triamcinolone injections in recent onset central retinal vein occlusion

PURPOSE

To evaluate the effects of repeated intravitreal injections of bevacizumab (IVB) versus triamcinolone acetonide (IVT) in the treatment of acute central retinal vein occlusion (CRVO).

METHODS

In this randomized clinical trial, 86 eyes with recent onset (<12 weeks) CRVO were assigned to two groups: IVB group (43 eyes) that received three monthly injections of 1.25 mg of IVB, and IVT group (43 eyes) that received two injections of 2 mg IVT 2 months apart. Outcomes were best-corrected visual acuity (BCVA), central macular thickness (CMT), and intraocular pressure (IOP) changes.

RESULTS

Mean BCVA improved significantly at 6 months in both groups; from 0.87 ± 0.49 to 0.41 ± 0.35 logMAR in IVB group, and from 0.81 ± 0.45 to 0.62 ± 0.48 logMAR in IVT group (p < 0.001). However, between-group differences reach a significant level at months 4 (p = 0.003) and 6 (p < 0.001) in favour of the IVB group. In terms of CMT reduction, the difference between the groups was statistically significant (p = 0.002) at month 6. Significant differences were noted more in the ischaemic cases in favour of the IVB group. Mean IOP rise was significantly higher in the IVT group at all visits.

CONCLUSIONS

Both 3-times monthly IVB injections and 2-times IVT injections could be effective in cases with recent onset CRVO up to 6 months. However, considering the better outcomes after IVB injections and the potential complications of IVT injections, we would recommend prescheduled repeated IVB injections for such cases. The observed favourable responses were more pronounced in the ischaemic types; nevertheless, this should be confirmed in larger studies.

[A cost-effectiveness study of dexamethasone implants in macular edema]

OBJECTIVE

To analyze the cost-effectiveness and benefits of a dexamethasone intravitreal implant (Ozurdex®, Allergan, Irvine, CA, USA.) in its clinically relevant applications.

MATERIAL AND METHODS

A total of 88 eyes of 86 patients with macular edema of > 300 μm measured by optical coherence tomography (Cirrus Zeiss, Dublin, CA, USA) were included in this two-year retrospective study, with a minimum of 6 months follow-up. The patients were divide into 3 groups: group 1 with macular edema in retinal vein occlusion, group 2 with non-infectious posterior uveitis, and group 3 with diabetic macular edema. The treatment was off-label but supported by the literature. Before implantation, and on days 1, 30, 60, 90 and 180, corrected visual acuity (Snellen), central retinal thickness, intraocular pressure and biomicroscopy were evaluated. The cost-benefit analysis was tabulated by line of visual acuity gained, comparing the main therapeutic alternatives and assessment of the safety profile of the dexamethasone intravitreal implant (Ozurdex®, Allergan, Irvine, CA, USA).

RESULTS

The results of this study did not differ from the published studies, in terms of visual acuity improvement in 63.3% of cases, and with central macular thickness improvement in 97% of cases. There were relapses, which occurred after 120 days on average, and the need for retreatment was 40.9%. Increased intraocular pressure >23 mm Hg was among the side effects in 29.54%, and was controlled with topical treatment, except in 1.13% requiring surgical treatment. The development of cataract was 44.7%, and 10.6% required surgery. Treatment results showed less frequent use of Ozurdex® than other treatments for disease control, being a cost saving option.

DISCUSSION

Cost-effectiveness analyses are clinically relevant when applying treatment strategies in patients with macular edema. Dexamethasone intravitreal implant appears to be a safe and efficient therapy.

Intravitreal bevacizumab in acute central/hemicentral retinal vein occlusions: three-year results of a prospective clinical study

PURPOSE

To prospectively evaluate the effects of intravitreal bevacizumab (IVB, Avastin; Genentech, Inc., San Francisco, CA) injections in patients with acute central/hemicentral retinal vein occlusions (C/HCRVOs) (≤1 month after the occlusion was diagnosed) over the course of 3 years.

METHODS

The study included 57 patients with unilateral acute C/HCRVOs. Initially, the treatment for acute C/HCRVO patients consisted of 4 consecutive IVB injections administered off-label at a dose of 2.5 mg per injection, with each injection spaced ∼45 days apart. Thereafter, IVB therapy was flexible, and subsequent injections were administered during scheduled visits whenever a best corrected visual acuity (BCVA) loss of ≥5 Early Treatment Diabetic Retinopathy Study (ETDRS) letters occurred and/or iris/angle neovascularization appeared (regardless of the intraocular pressure level). Changes in the BCVA and foveal thickness (FT), number of IVB injections administered, and incidence of neovascular glaucoma (NVG) were estimated.

RESULTS

The increase in the BCVA score at month 36 was 17.15 (ETDRS letters) (P<0.0001) in cases of nonischemic and 26.81 (ETDRS letters) (P<0.01) in cases of ischemic occlusions. At the end of the follow-up, the proportion of BCVA score improvements greater than 15 ETDRS letters was similar in patients with both forms of occlusions (measured in 45.5% of nonischemic and 45.8% of ischemic patients) (P=0.977). There were significant reductions in FT from baseline values to 230±40.50 μm (P=0.0001) in patients with nonischemic occlusions and 270±40.50 μm (P=0.0001) in patients with ischemic forms. There was a significant difference (P<0.03) in the number of IVB injections administered in patients with nonischemic C/HCRVOs (8.7±1.58) compared to patients with ischemic occlusions (9.7±1.78). NVG occurred in 2 cases of ischemic occlusions.

CONCLUSIONS

The 3-year IVB therapy provided sustained vision and FT gains in most phakic patients with acute C/HCRVOs, making this treatment option a rational and viable therapeutic strategy. Bevacizumab was more effective in patients with ischemic occlusions who required a significantly higher number of injections.

Drug treatment of macular oedema secondary to central retinal vein occlusion: a network meta-analysis

OBJECTIVE

To indirectly compare aflibercept, bevacizumab, dexamethasone, ranibizumab and triamcinolone for treatment of macular oedema secondary to central retinal vein occlusion using a network meta-analysis (NMA).

DESIGN NMA DATA SOURCES

The following databases were searched from January 2005 to March 2013: MEDLINE, MEDLINE In-process, EMBASE; CDSR, DARE, HTA, NHSEED, CENTRAL; Science Citation Index and Conference Proceedings Citation Index-Science.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Only randomised controlled trials assessing patients with macular oedema secondary to central retinal vein occlusion were included. Studies had to report either proportions of patients gaining ≥3 lines, losing ≥3 lines, or the mean change in best corrected visual acuity. Two authors screened titles and abstracts, extracted data and undertook risk of bias assessment. Bayesian NMA was used to compare the different interventions.

RESULTS

Seven studies, assessing five drugs, were judged to be sufficiently comparable for inclusion in the NMA. For the proportions of patients gaining ≥3 lines, triamcinolone 4 mg, ranibizumab 0.5 mg, bevacizumab 1.25 mg and aflibercept 2 mg had a higher probability of being more effective than sham and dexamethasone. A smaller proportion of patients treated with triamcinolone 4 mg, ranibizumab 0.5 mg or aflibercept 2 mg lost ≥3 lines of vision compared to those treated with sham. Patients treated with triamcinolone 4 mg, ranibizumab 0.5 mg, bevacizumab 1.25 mg and aflibercept 2 mg had a higher probability of improvement in the mean best corrected visual acuity compared to those treated with sham injections.

CONCLUSIONS

We found no evidence of differences between ranibizumab, aflibercept, bevacizumab and triamcinolone for improving vision. The antivascular endothelial growth factors (VEGFs) are likely to be favoured because they are not associated with steroid-induced cataract formation. Aflibercept may be preferred by clinicians because it might require fewer injections.

SYSTEMATIC REVIEW REGISTRATION

Not registered.

Morphological and electrophysiological outcome in prospective intravitreal bevacizumab treatment of macular edema secondary to central retinal vein occlusion

PURPOSE

To evaluate intravitreal bevacizumab (IVB) treatment in patients with central retinal vein occlusion (CRVO) by spectral domain optical coherence tomography (OCT) and electroretinography (ERG).

METHODS

Twenty-two CRVO patients were treated with IVB injections and followed for 1 year. Morphological effect of treatment was observed with fluorescent angiography and OCT. Functional effect was followed with best corrected visual acuity (BCVA) and ERG: combined rod-cone response of the standard full-field ERG (dark adapted 3.0 ERG), photopic negative response (PhNR), and pattern ERG (PERG).

RESULTS

Best corrected visual acuity (BCVA) improved by 18.2 letters after 6 months (p ≤ 0.001) and additional 4.7 letters by the 12th month (p ≤ 0.001). The central retinal thickness of 829.8 ± 256.7 μm decreased to 398.8 ± 230 μm (p ≤ 0.001) after 6 months and to 303.7 ± 128.9 μm during the following 6 months (p ≤ 0.001). The total macular volume (14.4 ± 4.2 mm(3)) decreased to 9.6 ± 3.2 mm(3) and 8.5 ± 2.0 mm(3) after 6 months and 1 year of treatment, respectively (p ≤ 0.001). Electrophysiological measures improved significantly after 6 months and 1 year of treatment: the a-wave implicit time of dark adapted 3.0 ERG from 25.6 ± 2.3 to 24.1 ± 2.1 and 24.1 ± 2.0 ms (p ≤ 0.01); the PhNR from -5.9 ± 6.6 to -9.4 ± 6.1 and -10.4 ± 4.6 µV (p ≤ 0.05); the PERG P50 amplitude from 0.2 ± 0.3 to 0.9 ± 0.6 and 1.1 ± 0.6 µV (p ≤ 0.001); and N95 amplitude from 0.4 ± 0.6 to 1.2 ± 0.9 and 1.6 ± 0.9 µV (p ≤ 0.001).

CONCLUSIONS

Intravitreal bevacizumab (IVB) treatment of macular edema due to CRVO improved standard morphological measures and the electrophysiological function of outer and inner retinal layers, which was most evident in central retina.

Dexamethasone intravitreous implant versus bevacizumab for central retinal vein occlusion-related macular oedema: a prospective randomized comparison

BACKGROUND

To compare the efficiency of dexamethasone implants to bevacizumab injections in macular oedema secondary to central retinal vein occlusion.

DESIGN

Randomized clinical trial at Cairo University Hospitals.

PARTICIPANTS

Sixty eyes of 60 newly diagnosed patients with macular oedema secondary to central retinal vein occlusion with best corrected visual acuity 0.3 logMAR (6/12) to counting fingers, no evidence of retinal ischaemia and/or neovascularization on fluorescein angiography and central subfield thickness ≥300 μm on ocular coherence tomography.

METHODS

Patients were randomly assigned (30 eyes each group) to either intravitreal dexamethasone implant or bevacizumab injections repeated whenever needed. Best corrected visual acuity and ocular coherence tomography were done at baseline and monthly for 6 months.

MAIN OUTCOME MEASURES

Comparing best corrected visual acuity and central foveal subfield thickness between both groups during the 6-month period.

RESULTS

There was no significant difference in best corrected visual acuity between the two groups during the 6 months (P-values > 0.05). The bevacizumab group had a statistically significant thinner central subfield thickness at 1 month (P-value 0.006) and no statistically significant difference for the rest of the 6 months (P-values > 0.05). There was a statistically significant higher intraocular pressure for dexamethasone implant group (compared with bevacizumab) at 3-6 months (P-values < 0.05), respectively.

CONCLUSION

Both drugs provided effective best corrected visual acuity improvements and central subfield thickness reductions that showed no statistically significant difference between the two groups.

Comparison between Intravitreal Triamcinolone with Grid Laser Photocoagulation versus Bevacizumab with Grid Laser Photocoagulation Combinations for Branch Retinal Vein Occlusion

Purpose. To compare the efficacy of intravitreal triamcinolone (IVT) and intravitreal bevacizumab (IVB), both combined with grid laser photocoagulation (GLP) for macular edema (ME) secondary to branch retinal vein occlusion (BRVO). Methods. Retrospective, comparative study. The newly diagnosed patients with ME secondary to BRVO who were treated with IVT and GLP or IVB and GLP were included. The main outcome measures were changed in the best corrected visual acuity (BCVA) and central retinal thickness (CRT) from the baseline to month 24. Results. Ninety-nine eyes of 99 patients were included. The change in BCVA was not statistically different in any time points between the two groups (P > 0.05, for all). The change in CRT was not statistically different in any time points between the two groups (P > 0.05, for all). The mean number of injections at month 24 was 2.38 ± 1.06 in the IVT+GLP group and 4.17 ± 1.30 in the IVB+GLP group (P = 0.0001). The need for cataract surgery (P = 0.01) and secondary glaucoma (P = 0.03) occurrence were more common in IVT group. Conclusion. Both treatment modalities were effective in the treatment of ME secondary to BRVO. The number of injections was significantly lower in the IVT group than in the IVB group; however cataract and secondary glaucoma were more frequent in the IVT+GLP group than in the IVB+GLP group.

Best practices for treatment of retinal vein occlusion

PURPOSE OF REVIEW

Retinal vein occlusion (RVO) is a sight-threatening retinal vascular disorder associated with macular edema and neovascularization. Until recently, the standard of care for branch RVO-associated macular edema was grid laser photocoagulation and observation for central RVO-associated macular edema. Neovascularization was treated with scatter laser photocoagulation. The purpose of this article is to review recent findings that have changed our treatments of RVO.

RECENT FINDINGS

The recent development of intravitreal pharmacotherapy has demonstrated benefit with anti-vascular endothelial growth factor (VEGF) agents and corticosteroids for the treatment of RVO-associated macular edema. The intravitreal use of FDA-approved ranibizumab (Lucentis) and a sustained release dexamethasone implant (Ozurdex), along with off-label bevacizumab (Avastin) and preservative-free triamcinolone, has significantly expanded our treatment options and replaced standard of care for treatment of RVO-associated macular edema. Whereas anti-VEGF agents can also induce rapid regression of neovascularization, scatter laser photocoagulation remains the standard of care to prevent neovascular complications.

SUMMARY

Intravitreal pharmacotherapy has revolutionized our treatment of retinal vascular diseases, including RVO. Although these intravitreal agents are effective, our understanding of their specific indications and long-term roles is still evolving. Furthermore, until the underlying occlusive pathophysiology of RVO can be addressed, our treatments will be limited to temporizing therapies against a chronic disease.

Potential anti-vascular endothelial growth factor therapies for central retinal vein occlusion

Central retinal vein occlusion (CRVO) remains an important cause of visual loss. Impaired venous drainage leads to retinal hypoxia with upregulation and release of vascular endothelial growth factor (VEGF). VEGF increases vascular permeability and leads to the breakdown of the blood-retinal barrier, with the development of macular oedema. Treatment strategies for macular oedema in CRVO currently under evaluation focus on VEGF blockage. Bevacizumab is a humanized monoclonal antibody that blocks VEGF. It has been evaluated in a clinical trial that compared intravitreal injections of bevacizumab 1.25 mg with sham injections every 6 weeks. At the end of a 24-week follow-up period, 60.0% of patients in the bevacizumab group had gained ≥ 15 letters compared with 20.0% in the control group (p=0.003). Aflibercept (previously VEGF Trap-Eye) is a 115  kD decoy receptor fusion protein. Aflibercept is capable of binding both VEGF and placental growth factor (PlGF). By blocking both VEGF and PlGF, aflibercept could be more effective than other anti-VEGF drugs. Two clinical trials have evaluated the efficacy of aflibercept for the treatment of macular oedema in CRVO: COPERNICUS and GALILEO. Both included a similar 6-month phase, during which patients were randomized to receive either an intravitreal injection of aflibercept 2 mg or a sham injection every month. In a second 6-month phase of the GALILEO study, patients in the treatment group were treated on an as needed (PRN) basis with aflibercept, while patients in the placebo group continued with sham injections. In the second 6-month phase in the COPERNICUS study, all patients were treated with aflibercept on a PRN basis. Treatment with aflibercept led to an improvement in visual acuity of ≥ 15 letters in 55.3% (COPERNICUS) and 60.2% of patients (GALILEO). Patients initially in the placebo group and then treated PRN gained only a mean of 3.8 letters, with 30.1% achieving a visual gain of ≥ 15 letters (COPERNICUS). The percentage of patients that improved by ≥ 15 letters was 32.4% for the group receiving sham injections throughout the GALILEO study. In summary, VEGF blockage has been proven to improve visual outcomes in patients with macular oedema due to CRVO. However, an important disadvantage of anti-VEGF drugs is the need for frequent reinjections and even more frequent control visits. Further advances are needed in order to improve quality of life and reduce the burden to healthcare systems.

Visual Acuity Outcome and Predictive Factors after Bevacizumab for Central Retinal Vein Occlusion

Purpose.

To evaluate the 12-month outcome and predictive factors of visual acuity (VA) changes following bevacizumab therapy for central retinal vein occlusion (CRVO).

Methods.

A total of 50 eyes from 50 patients with CRVO were consecutively included in this prospective study. Predictive factors were assessed by comparing baseline characteristics of patients classified into 3 groups: those showing a decrease in VA; those displaying a change in Early Treatment Diabetic Retinopathy Study (ETDRS) letter score between 0 and 15; and those in whom an increase in VA ≥15 letters was achieved. Baseline variables considered in the analyses of predictive factors were demographic and clinical characteristics.

Results.

Mean baseline ETDRS letter score was 20±12 and mean macular thickness was 575.1±152.7 µm. Mean final ETDRS letter score improved significantly, reaching 27±20, p=0.04, while mean macular thickness decreased significantly to 391.1±229.6 µm, p<0.001. The predictive factors associated with an increase in VA ≥15 ETDRS letters were younger age (p=0.002), shorter duration of symptoms before treatment initiation (p=0.001), and a higher visual acuity pretreatment (p=0.004). The frequency of ischemic CRVO and low vision at baseline was higher among nonresponsive patients (p=0.005).

Conclusions.

Intravitreal bevacizumab seems to be an effective primary treatment option for macular edema due to CRVO. Its main drawback is that multiple injections are often necessary to maintain visual improvement. Early injections of bevacizumab in young patients in whom VA is relatively preserved leads to a significant improvement in VA. Ischaemic CRVO and poor baseline VA are associated with nonresponse to such therapy.

Bevacizumab for macular edema in central retinal vein occlusion: a prospective, randomized, double-masked clinical study

PURPOSE

To evaluate the efficacy of intraocular injections with bevacizumab in patients with macular edema (ME) secondary to central retinal vein occlusion (CRVO).

DESIGN

Prospective, randomized, sham injection-controlled, double-masked clinical trial.

PARTICIPANTS

Sixty patients with ME secondary to CRVO.

METHODS

At baseline, patients were randomized 1:1 to receive intraocular injections of bevacizumab or sham injections every 6 weeks for 6 months.

MAIN OUTCOME MEASURES

The primary outcome measure was the proportion of patients gaining at least 15 letters at 6 months. Secondary outcome measures included mean change from baseline best-corrected visual acuity (BCVA), foveal thickness, and neovascular glaucoma.

RESULTS

At the end of follow-up, 18 of 30 patients (60.0%) in the study group had gained ≥15 letters compared with 6 of 30 patients (20.0%) in the control group (P=0.003). The BCVA improved by 14.1 letters at 24 weeks compared with a decrease of 2.0 letters in the control group (P < 0.003). The mean decrease in central retinal thickness (CRT) was significantly greater in the study group (426 μm) than in the control group (102 μm) at all time points up to week 24 (P < 0.001). No residual edema, defined as CRT <300 μm at 24 weeks, was found in 26 of 30 patients (86.7%) in the treatment group compared with 6 of 30 patients (20%) in the control group (P < 0.001). In the sham group, 5 of 30 patients (16.7%) had developed iris rubeosis at week 24. No patients in the study group had rubeosis at week 24 (P=0.052). There were no events of endophthalmitis, retinal tear, or retinal detachment during the 24-week treatment period. No serious non-ocular adverse events were reported.

CONCLUSIONS

Intraocular injections of bevacizumab given every 6 weeks for 6 months improve visual acuity (VA) and reduce ME significantly compared with sham.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.