Updates on the Management of Ocular Vasculopathies with VEGF Inhibitor Conbercept

Kavain Alleviates Choroidal Neovascularization Via Decreasing the Activity of the HIF-1α/VEGF-A/VEGFR2 Signaling Pathway and Inhibiting Inflammation

Purpose

Neovascular age-related macular degeneration (nAMD) is a prevalent cause of blindness in the elderly. Standard treatment includes anti-vascular endothelial growth factor (anti-VEGF) drugs, such as aflibercept. However, anti-VEGF drugs may have limited efficacy and cause drug resistance. This study explores whether Kavain, an anti-inflammatory molecule from Piper methysticum, can treat choroidal neovascularization (CNV).

Methods

Various experiments were conducted to assess the Kavain's toxicity. The impact of Kavain on in vitro cultured endothelial cells was examined through 5-ethynyl-20-deoxyuridine (EdU) assays, transwell migration assays, and tube formation assays. The therapeutic effects of Kavain on CNV were investigated using a laser-induced CNV mice model. To elucidate the mechanism of Kavain, network pharmacology analysis, molecular docking, and western blots were performed.

Results

Kavain exhibited no apparent toxicity both in vitro and in vivo. Kavain significantly decreased endothelial cell viability, proliferation, migration, and tube formation ability in a dose-dependent manner compared to the hypoxia groups (P<0.05). Kavain alleviated CNV in the laser-induced CNV mouse model compared to the control groups (P<0.05). These effects were statistically significantly enhanced in the Kavain plus aflibercept groups (P<0.05). Following Kavain administration, the expression levels of various inflammatory factors were markedly reduced in retinal pigment epithelium (RPE)/choroid complexes (P<0.05). Mechanistically, Kavain decreased the activity of the hypoxia-inducible factor 1α (HIF-1α)/VEGF-A/ VEGF receptor 2 (VEGFR2) signaling pathway.

Conclusion

Our study is the first to demonstrate Kavain's potential as a promising treatment for nAMD, owing to its dual effects of anti-inflammation and anti-angiogenesis.

Prognostic factors for intravitreal conbercept in the treatment of choroidal neovascularization secondary to pathological myopia

PURPOSE

To identify risk factors influencing visual outcomes in patients with pathological myopia-associated choroidal neovascularization (PM-CNV) following intravitreal injections of conbercept.

METHODS

A total of 86 eyes from 86 patients received intravitreal conbercept in a 1 + PRN regimen. After the initial injection, patients were followed for 12 months. They were categorized into two groups based on their 12-month visual acuity change: those who achieved greater than a one-line improvement in BCVA (improved group; n = 65) and those who experienced a one-line or lesser improvement or a decrease in BCVA (non-improved group; n = 21).

RESULTS

Over the 12-month period, the mean BCVA in the improved group significantly improved from 0.82 to 0.41 LogMAR. In the non-improved group, BCVA changed from 1.24 to 1.09 LogMAR. Similarly, the mean CRT decreased from 426.21 μm at baseline to 251.56 μm at 12 months in the improved group, and from 452.47 to 382.45 μm in the non-improved group. Multivariable logistic regression analyses revealed that older age (OR 1.287; 95% CI 1.019-1.625; P = 0.034), poorer baseline BCVA (OR 6.422; 95% CI 1.625-25.384; P = 0.008), the presence of subfoveal CNV (OR 4.817; 95% CI 1.242-18.681; P = 0.023), and organized interlacing patterns of CNV morphology (OR 5.593; 95% CI 1.397-22.392; P = 0.015) emerged as independent risk factors correlated with worsened visual prognosis following intravitreal conbercept injections.

CONCLUSIONS

Conbercept demonstrates significant efficacy and safety in treating PM-CNV. Key factors influencing visual recovery post-treatment include older age, poorer baseline BCVA, the presence of subfoveal CNV, and organized interlacing patterns of CNV morphology.

Clinical outcomes of different regimens of intravitreal Conbercept for the treatment of choroidal neovascularization secondary to pathological myopia

PURPOSE

To assess the clinical outcomes of two intravitreal injection regimens of Conbercept used to treat choroidal neovascularization secondary to pathological myopia (PM-CNV).

METHODS

A total of 72 eyes of 72 patients were treated: 39 eyes received a single injection followed by treatment pro re nata (1 + PRN); 33 eyes first received 3 consecutive monthly injections (3 + PRN) then followed by PRN. After initial injection, patients were followed up for 12 months.

RESULTS

The mean age of 72 patients was 45.3 ± 5.1 years, with the mean diopter of -10.62 ± 3.24D. The best corrected visual acuity (BCVA) was 0.86 ± 0.23 LogMAR with 1 + PRN and 0.90 ± 0.19 LogMAR with 3 + PRN at baseline (P = 0.422), 0.36 ± 0.07 and 0.33 ± 0.05 LogMAR at month 3 (P = 0.026); and 0.33 ± 0.03 and 0.32 ± 0.02 LogMAR at month 12 (P = 0.096). The central retinal thickness (CRT) was 333.5 ± 22.7 μm with 1 + PRN and 341.2 ± 20.9 μm with 3 + PRN at baseline (P = 0.139), 281.53 ± 10.28 and 273.15 ± 13.24 μm at month 3 (P = 0.004); 266.83 ± 8.14 and 264.91 ± 9.27 μm at month 12 (P = 0.350). The number of injections in the 1 + PRN group was significantly lower than that observed in the 3 + PRN group (2.15 ± 1.06 versus 3.36 ± 0.74; P < 0.001). During the follow-up, no serious ocular complications and adverse reactions related to Conbercept and injections occurred.

CONCLUSIONS

Both injection regimens resulted in similar visual outcomes in PM-CNV patients. The 1 + PRN regimen had fewer injections and might be more suitable in this patient population.

The Association of Axial Length with Macular Microvascular Changes in Chinese Diabetic Retinopathy Patients

Objective

To use optical coherence tomography angiography (OCTA) to compare macular blood flow density, subfoveal choroidal thickness (SFCT) and outer retina thickness (ORT) in non-proliferative diabetic retinopathy (NPDR) patients with different axial length (AL).

Methods

Total 42 patients with NPDR with different eye axis were divided into three groups: group A: 22 mm≤AL<24 mm; group B: 24 mm≤AL<26 mm; group C: AL≥26 mm. Superficial capillary plexus (SCP) in the macular area, vascular length density (VLD) and vascular perfusion density (VPD) in the foveal region, the parafoveal region, the perifoveal region and whole macular region were analyzed. The correlations among axial length, macular microvascular density, SFCT and outer retinal thickness (ORT) were analyzed.

Results

Compared with group A and B, VLD and VPD in group C were significantly lower except the foveal region, and VLD and VPD were negatively correlated with AL. The difference in SFCT among group A, B and C was significant, and SFCT was negatively correlated with AL. Compared with group A, parafoveal ORT in group C was significantly lower than that in group A, and parafoveal ORT was negatively correlated with AL.

Conclusion

In NPDR patients with different AL, macular microvascular density, SFCT, and parafoveal ORT decreased with the increase of AL.

Obstructive Sleep Apnea is Related with the Risk of Retinal Vein Occlusion

BACKGROUND

Retinal vein occlusion (RVO) was a vision-threatening retinal vascular disorder, however, the relationship between obstructive sleep apnea (OSA) and RVO risk remained unclear.

METHODS

A total of 45 RVO cases and 45 controls between April 2018 and April 2020 were included. All the participants underwent full-night polysomnography (PSG) and thus detected the severity of OSA. Besides, the relationship between the apnea-hypopnea index (AHI) and oxidative and inflammatory biomarkers, including 8-hydroxy-2 deoxyguanosine (8-OHdG), C-reactive protein (CRP), interleukin 1 beta (IL1β), interleukin 6 (IL6) and tumor necrosis factor alpha (TNFα) were detected. The incidences of macular edema (ME) and neovascular glaucoma (NVG) were detected in a three-months follow-up.

RESULTS

In this case-control study, it was found that OSA incidence was increased in the RVO cases comparing with the cataract controls. Advanced analyses about the RVO subtypes demonstrated that incidence of OSA was higher in the central RVO (CRVO) cases comparing with branch RVO (BRVO) cases. Plasma samples from OSA cases demonstrated relatively higher concentrations of oxidative stress parameters and inflammatory biomarkers, including 8-OHdG, CRP, IL1β, and IL6, in the RVO cases. Significant linear correlations between AHI and oxidative/inflammatory biomarkers were detected, and advanced analyses on the OSA subtypes demonstrated that these biomarkers were significantly higher in cases with later stages of OSA. In a three months follow-up, an impaired visual activity improvement rate and increased ME incidence in the OSA group among all the RVO cases were detected.

CONCLUSION

OSA was related with an increased incidence of RVO. Besides, OSA would lead to increased oxidative and inflammatory biomarkers concentrations in the RVO cases. OSA could be used as a harmful prognostic factor of visual activity improvement and ME incidences. These findings highlighted the role of OSA in the development of RVO.