Short-term effect of intravitreal conbercept injection on major and macular branch retinal vein occlusion

Effect of Conbercept Treatment on Macular Edema and Microvascular Structure in Eyes with Retinal Vein Occlusions

Objective

Methods

Results

Conclusion

Efficacy of Modified Treat-and-Extend Regimen of Aflibercept for Macular Edema from Branch Retinal Vein Occlusion: 2-Year Prospective Study Outcomes

This study aimed to evaluate the long-term (24-month) efficacy and safety of a modified treat-and-extend (mTAE) regimen of aflibercept for macular edema (ME) due to branch retinal vein occlusion (BRVO). This was a prospective multicenter intervention study. We evaluated 50 eyes in 50 patients with ME due to BRVO enrolled between October 2016 and September 2017. The patients received intravitreal aflibercept (IVA) injections according to a mTAE regimen for 24 months. This study reports the secondary endpoints of best-corrected visual acuity (BCVA) and central subfield thickness (CST) at 24 months and compares them with previously reported primary endpoints. Compared with baseline BCVA and CST of 0.33 (0.27) and 488 (165) µm (mean (standard deviation)), respectively, BCVA and CST were significantly improved at 12 and 24 months (12 months: 0.059 (0.19) LogMAR and 299 (112) µm; 24 months: 0.034 (0.18) LogMAR and 272 (81) µm, respectively; both p < 0.0001). Over the 24-month period, the mean number of IVA injections and clinic visits was 7.4 (3.3) and 11.1 (2.0), respectively. The mTAE regimen of IVA injections for ME due to BRVO was effective for improving BCVA and reducing CST over 24 months. This regimen shows promise for reducing the number of injections and clinic visits.

Low-Dose Recombinant Adeno-Associated Virus-Mediated Inhibition of Vascular Endothelial Growth Factor Can Treat Neovascular Pathologies Without Inducing Retinal Vasculitis

The wet form of age-related macular degeneration is characterized by neovascular pathologies that, if untreated, can result in edemas followed by rapid vision loss. Inhibition of vascular endothelial growth factor (VEGF) has been used to successfully treat neovascular pathologies of the eye. Nonetheless, some patients require frequent intravitreal injections of anti-VEGF drugs, increasing the burden and risk of complications from the procedure to affected individuals. Recombinant adeno-associated virus (rAAV)-mediated expression of anti-VEGF proteins is an attractive alternative to reduce risk and burden to patients. However, controversy remains as to the safety of prolonged VEGF inhibition in the eye. Here, we show that two out of four rAAV serotypes tested by intravitreal delivery to express the anti-VEGF drug conbercept lead to a dose-dependent vascular sheathing pathology that is characterized by immune cell infiltrates, reminiscent of vasculitis in humans. We show that this pathology is accompanied by increased expression in vascular cell adhesion molecule 1 (VCAM1) and intercellular adhesion molecule 1 (ICAM1), both of which promote extravasation of immune cells from the vasculature. While formation of the vascular sheathing pathology is prevented in immunodeficient Rag-1 mice that lack B and T cells, increased expression of VACM1 and ICAM1 still occurs, indicating that inhibition of VEGF function leads to expression changes in cell adhesion molecules that promote extravasation of immune cells. Importantly, a 10-fold lower dose of one of the vectors that cause a vascular sheathing pathology is still able to reduce edemas resulting from choroidal neovascularization without causing any vascular sheathing pathology and only a minimal increase in VCAM1 expression. The data suggest that treatments of neovascular eye pathologies with rAAV-mediated expression of anti VEGF drugs can be developed safely. However, viral load needs to be adjusted to the tropisms of the serotype and the expression pattern of the promoter.

Short-term effects of intravitreal Conbercept injection combined with laser photocoagulation on macular edema secondary to ischemic retinal vein occlusion

AIM

To observe changes in the best-corrected visual acuity (BCVA), central macular thickness (CMT), and central choroidal thickness (CCT) of patients with macular edema (ME) secondary to ischemic retinal vein occlusion (iRVO) following intravitreal Conbercept injection.

METHODS

This retrospective study included 33 eyes from 33 patients who received intravitreal injections of Conbercept for ME secondary to iRVO. Treatments were performed on a 3+pro re nata (3+PRN) basis. All of the patients were examined by fundus fluorescein angiography and spectral domain optical coherence tomography at the first visit. Laser photocoagulation was performed in the nonperfusion area of the retina of all eyes after the first injection. BCVA, CMT, and CCT were observed before and after 6mo of treatment. The number of injections necessary to achieve improved vision was also noted.

RESULTS

Following Conbercept treatment, the mean BCVA significantly improved from 0.81±0.39 at baseline to 0.41±0.25 and 0.43±0.29 logMAR in the third and sixth months, respectively (both P=0.000). The CMT of the patients at baseline was 556.75±98.57 µm; 304.78±68.53 and 306.85±76.77 µm 3 and 6mo after treatment, respectively (both P=0.000 vs baseline). The CCTs of the patients at baseline, 3 and 6mo after treatment were 304.63±57.83, 271.31±45.53, and 272.29±39.93 µm, respectively (P=0.026 and 0.035 vs baseline). No severe adverse event relevant to the therapy was noted, and the average number of injections delivered was 3.35.

CONCLUSION

Intravitreal Conbercept injection combined with laser photocoagulation appears to be a safe and effective treatment for ME secondary to iRVO in the short-term.

Efficacy of intravitreal Lucentis injection on major and macular branch retinal vein occlusion

Background

The objective of our study was to assess the efficacy of intravitreal Lucentis injection on major and macular branch retinal vein occlusion (BRVO).

Methods

In this retrospective analysis, 43 patients (major BRVO n = 24; macular BRVO, n = 19) were treated with intravitreal injection of Lucentis with a 1 + PRN regimen, which is diagnosed by fluorescein fundus angiography (FFA). “1 + PRN”, namely, one intravitreal injection of Lucentis at the baseline, and then continue or stop according to the condition of the patient. The following observation indexes were measured at baseline and follow-up (1–6 months): best corrected visual acuity (BCVA), foveal thickness (CFT), total retinal volume with macular diameter of 6 mm. During the follow-up, repeated injections were given according to patients’ demand, and the number of injections was recorded.

Result

The observation indexes of patients with BRVO were significantly improved after 6 months of Lucentis treatment in both major and macular groups, including BCVA, CFT and the retinal volume of the 6 mm-diameter macula. Interestingly, there were significant differences in the therapeutic effect between the two groups, and the macular group had better therapeutic effect than the major group with the less number of repeated injections.

Conclusions

To sum up, intravitreal injection of Lucentis was effective for both major and macular BRVO, and the efficacy in macular subtype group was better than that in major subtype group with the more obviously improvement and the less number of injections.

Updates on the Management of Ocular Vasculopathies with VEGF Inhibitor Conbercept

Purpose: To provide a detailed review on the therapeutic efficacy of conbercept for the management of ocular vasculopathies. Methods: A comprehensive literature search of various electronic databases was performed. Results: Ocular vasculopathy is one of the major causes of visual impairment and blindness which includes a range of disorders. Vascular endothelial growth factor (VEGF) regulates angiogenesis, enhances vascular permeability, and drives the formation of neovascularization. Anti-VEGF therapy has been shown to prevent vision loss or potentially improve vision in patients with exudative or neovascular retinal disease. The most recent anti-VEGF drug in China is conbercept. In the USA and Europe, bevacizumab is the most recently approved anti-VEGF agent. Conclusions: Conbercept serves as another anti-VEGF option for patients with neovascular AMD and other retinal vascular disorders. There have not been many clinical trials that study conbercept as compared with other currently available anti-VEGF drugs. There is a need for large-scale, well-designed, randomized clinical trials to ensure its long-term safety and efficacy and to determine if it has any advantages over other anti-VEGF agents.

Clinical characteristics of branch retinal vein occlusion with increased retinal haemorrhage during treatment for macular oedema

This study was performed to evaluate clinical characteristics of branch retinal vein occlusion (BRVO) patients with increased retinal haemorrhage during macular oedema (MO) treatment. Patients were divided into increased and non-increased retinal haemorrhage groups. The former group was sub-divided based on the degree of increase: < 50% or ≥ 50%. Baseline characteristics, clinical data, and best vision achieved before and after increased retinal haemorrhage were assessed. Sixty-eight eyes of 68 patients were included. Forty-six eyes were non-increased, 11 eyes experienced < 50% increase in retinal haemorrhage, and 11 eyes had ≥ 50% increase. Ischaemic BRVO was related to increased haemorrhage based on the multivariate analysis. The ≥ 50% increase group exhibited higher baseline central subfield macular thickness (CSMT), poorer baseline best corrected visual acuity (BCVA), and longer mean periods between the final intravitreal injections and the time increased retinal haemorrhages were observed, compared to the < 50% group. The best vision achieved before and after increased haemorrhage was significantly worse in the ≥ 50% group. In conclusion, the ischaemic type of BRVO is related to increased retinal haemorrhage during MO treatment, and a ≥ 50% increase in haemorrhages is associated with higher CSMT and poorer BCVA at baseline, with poor visual gain.

A comparison of the effect of intravitreal dexamethasone implant on macular and branch retinal vein occlusion. A real life experience

PURPOSE

This study aimed to compare the effects of intravitreal dexamethasone (IVDx) implants on branch retinal vein occlusions (BRVOs) and macular vein occlusions (MVOs).

METHODS

Seventeen consecutive patients with MVO and 18 patients with BRVO, whose foveal thicknesses were greater than 300 µm, were recruited for this study. BRVO and MVO patients were diagnosed by means of fundus fluorescein angiography. Patients were treatment-naive. Initially, each patient in both the BRVO and MVO groups received an IVDx implant, and then a pro re nata IVDx regimen was initiated. Primary outcomes included VA gain, intraocular pressure (IOP) changes, macular ischemia, central macular thickness, retinal neovascularization, and number of IVDx injections. Follow-up time was 12 months.

RESULTS

The MVO group initially had significantly lower central macular thickness and a lower percentage of macular ischemia and systemic hypertension than those in the BRVO group (p = 0.001, 0.045, and 0.010, respectively). There was a statistically significant VA gain in both groups (p < 0.001), but the VA gain of the MVO group was greater than that of the BRVO group (p < 0.001). The mean total number of IVDx injections administered throughout the study period was significantly lower in the MVO group than in the BRVO group (1.3 ± 0.4 vs 2.0 ± 0.0; p = 0.001).

DISCUSSION

MVO and BRVO have different disease characteristics, and IVDx implants were more effective on the visual gain in patients with MVO than that of patients with BRVO who had higher numbers of IVDx injections.

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.