Systemic and Ocular Safety of Intravitreal Anti-VEGF Therapies for Ocular Neovascular Disease

CST3 alleviates retinal vascular leakage by regulating the Rap1 signaling pathway

Retinal vascular leakage is a major event in several retinal diseases, including diabetic retinopathy (DR). In a previous study, we demonstrated that the aqueous humor concentration of Cystatin C (CST3), a physiological inhibitor of cysteine protease, is negatively correlated with the severity of diabetic macular edema. However, its function in the retina has not been clearly elucidated. In this study, we found a significant decrease in the aqueous humor concentration of CST3 with DR progression. Furthermore, we found that CST3 was expressed in retinal endothelial cells and that its expression was significantly downregulated in high glucose-treated human retinal microvascular endothelial cells (HRMECs) and the retinal vessels of oxygen-induced retinopathy (OIR) mice. Silencing CST3 expression resulted in decreased HRMEC migration and tubule formation ability. Exogenous addition of the CST3 protein significantly improved HRMEC migration and tubular formation. In-vivo experiments demonstrated that CST3 silencing induced retinal vascular leakage in WT mice, while its intravitreal injection significantly reduced retinal leakage in OIR mice. Mechanistically, CST3 promoted the expression of the downstream adhesion molecules, claudin5, VE-cadherin, and ZO-1, in retinal vascular cells by regulating the Rap1 signaling pathway. Therefore, this study revealed a novel mechanism by which CST3 improves retinal vascular function and provided evidence that it is a potential therapeutic target for retinal vascular leakage.

Clinical manifestation and outcome of lung cancer patients with ocular metastasis: 16 case reports and systematic review

Ocular metastasis is a rare type of distant metastasis of lung cancer. Limited information is available regarding ocular symptoms, diagnosis, treatment, and prognosis. We reported 16 patients diagnosed with ocular metastasis from lung cancer treated at our hospital from January 1988 to March 2024 and conducted a systematic review of 100 patients retrieved from the PubMed database from January 2014 to December 2023. A pooled analysis was performed using individual-level patient data to generate the hazard ratio (HR) of the association between patient characteristics and overall survival. A total of 116 patients, 100 patients from the literature and 16 patients from our center, diagnosed with ocular metastasis from lung cancer were included in this study. Choroid metastasis was presented in 77 (66.4%) patients and was significantly associated with the onset of lung cancer with ocular symptoms and decreased vision; iris metastasis was significantly associated with small cell lung cancer (SCLC), high intraocular pressure, and ocular pain. Multivariate analyses revealed that males (HR, 2.488; 95% confidence interval [CI], 1.127-5.495), age ≥ 60 years (HR, 3.196; 95% CI, 1.391-7.341), and onset with ocular symptoms (HR, 4.312; 95% CI, 1.675-11.099) were significantly associated with overall survival. For non-SCLC (NSCLC) patients, compared with chemotherapy, targeted therapy (HR, 0.238; 95% CI, 0.087-0.651) and combined therapy (HR, 0.133; 95% CI, 0.017-0.822) have greater therapeutic efficacy. Chemotherapy combined with immunotherapy and targeted therapy are more effective than chemotherapy alone for ocular metastatic NSCLC patients. For patients with targetable mutations, new-generation tyrosine kinase inhibitors (TKIs) are preferred.

Recent Advances in Nanomedicine for Ocular Fundus Neovascularization Disease Management

As an indispensable part of the human sensory system, visual acuity may be impaired and even develop into irreversible blindness due to various ocular pathologies. Among ocular diseases, fundus neovascularization diseases (FNDs) are prominent etiologies of visual impairment worldwide. Intravitreal injection of anti-vascular endothelial growth factor drugs remains the primary therapy but is hurdled by common complications and incomplete potency. To renovate the current therapeutic modalities, nanomedicine emerged as the times required, which is endowed with advanced capabilities, able to fulfill the effective ocular fundus drug delivery and achieve precise drug release control, thus further improving the therapeutic effect. This review provides a comprehensive summary of advances in nanomedicine for FND management from state-of-the-art studies. First, the current therapeutic modalities for FNDs are thoroughly introduced, focusing on the key challenges of ocular fundus drug delivery. Second, nanocarriers are comprehensively reviewed for ocular posterior drug delivery based on the nanostructures: polymer-based nanocarriers, lipid-based nanocarriers, and inorganic nanoparticles. Thirdly, the characteristics of the fundus microenvironment, their pathological changes during FNDs, and corresponding strategies for constructing smart nanocarriers are elaborated. Furthermore, the challenges and prospects of nanomedicine for FND management are thoroughly discussed.

Efficacy comparison of anti-vascular endothelial growth factor drugs for the treatment of type 1 retinopathy of prematurity: A network meta-analysis of randomised controlled trials

PURPOSE

To compare the efficacy of different anti-vascular endothelial growth factor (VEGF) agents for the treatment of retinopathy of prematurity (ROP) in preterm infants.

METHODS

Seven databases were searched for eligible literature up to February 22, 2023. Studies were included if they were randomised controlled trials (RCTs) investigating the efficacy of anti-VEGF agents for ROP in infants. A network meta-analysis (NMA) was performed. We also conducted subgroup analyses to determine the efficacy ranking of regimens used in different regions. The odds ratio (OR), standardised mean difference (SMD), and surface under the cumulative ranking curve (SUCRA) were calculated for each outcome.

RESULTS

Thirteen RCTs of 10 different regimens, involving 1196 infants (2388 eyes), were identified. Bevacizumab (0.625 mg; OR = 0.16, 95% confidence interval [CI] 0.06-0.40, SUCRA = 80.6%) and conbercept (0.15 mg; OR = 0.08, 95% CI 0.02-0.30, SUCRA = 96.0%) were the most effective regimens in reducing the risk of ROP recurrence requiring retreatment in Western countries and China, respectively. Compared with laser therapy, bevacizumab (0.625 mg; SMD = 1.54, 95% CI 0.06-3.02) achieved significantly longer intervals between treatment and recurrence. No significant difference in the risk of retinal detachment was detected between any anti-VEGF agent and laser (p > 0.05).

CONCLUSIONS

Bevacizumab (0.625 mg) and conbercept (0.15 mg) appeared to be the most effective therapies for ROP in Western countries and China, respectively. More high-quality RCTs are warranted to evaluate the efficacy and long-term safety of anti-VEGF drugs for the management of ROP.

Dose-Related Side Effects of Intravitreal Injections of Humanized Anti-Vascular Endothelial Growth Factor in Rats: Glial Cell Reactivity and Retinal Ganglion Cell Loss

Purpose

In a previous study, we documented that the Intravitreal injections (IVIs) of bevacizumab in rats caused a retinal inflammatory response. We now study whether the IVI of other humanized anti-VEGF: ranibizumab and aflibercept also cause an inflammatory reaction in the rat retina and if it depends on the dose administered. Finally, we study whether this reaction affects retinal ganglion cell (RGC) survival.

Methods

Albino Sprague-Dawley rats received a single IVI of 5 µL of PBS or ranibizumab or aflibercept at the concentration used in clinical practice (10 µg/µL or 40 µg/µL) or at a lower concentration (0.38 µg/µL and 1.5 µg/µL) calculated to obtain within the rat eye the same concentration as in the human eye in clinical practice. Others received a single 5 µL IVI of a polyclonal goat anti-rat VEGF (0.015 µg/µL) or of vehicle (PBS). Animals were processed 7 days or 1 month later. Retinal whole mounts were immunolabeled for the detection of microglial, macroglial, RGCs, and intrinsically photosensitive RGCs (ipRGCs). Fluorescence and confocal microscopy were used to examine retinal changes, and RGCs and ipRGCs were quantified automatically or semiautomatically, respectively.

Results

All the injected substances including the PBS induced detectable side effects, namely, retinal microglial cell activation and retinal astrocyte hypertrophy. However, there was a greater microglial and macroglial response when the higher concentrations of ranibizumab and aflibercept were injected than when PBS, the antibody anti-rat VEGF and the lower concentrations of ranibizumab or aflibercept were injected. The higher concentration of ranibizumab and aflibercept resulted also in significant RGC death, but did not cause appreciable ipRGC death.

Conclusions

The IVI of all the substances had some retinal inflammatory effects. The IVI of humanized anti-VEGF to rats at high doses cause important side effects: severe inflammation and RGC death, but not ipRGC death.

Efficacy and safety of intravitreal faricimab for neovascular age-related macular degeneration: a systematic review and meta-analysis

We conducted a systematic review and meta-analysis to evaluate the visual, anatomical, and safety outcomes of the intravitreal faricimab, a novel vascular endothelial growth factor (VEGF)/angiopoietin-2 (Ang-2) bispecific agent, in neovascular age-related macular degeneration (nAMD) patients. The follow-up times in the included studies ranged from a minimum of 36 weeks to a maximum of 52 weeks. EMBASE, Ovid-Medline, Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, Scopus, the WHO ICTRP, ClinicalTrial.gov, the EU Clinical Trials Register, and Chinese Clinical Trial Registry (ChiCTR) were searched (The last literature search was performed on August 17, 2023) for randomized controlled trials (RCTs) comparing faricimab with control groups for neovascular age-related macular degeneration (nAMD). The risk of bias for eligible RCTs was independently assessed using the Cochrane Risk of Bias Tool by two authors (W.-T.Y. and C.-S.W.). The meta-analysis was conducted using Review Manager 5.4 software. The mean best corrected visual acuity (BCVA), central subfield thickness (CST), total choroidal neovascularization (CNV) area, and total lesion leakage were analyzed as continuous variables and the outcome measurements were reported as the weighted mean difference (WMD) with a 95% confidence interval (CI). The ocular adverse events and ocular serious adverse events were analyzed as dichotomous variables and the outcome measurements were analyzed as the odds ratios (ORs) with a 95% CI. Random-effects model was used in our study for all outcome synthesizing due to different clinical characteristics. Four RCTs with 1,486 patients were eligible for quantitative analysis. There was no statistically significant difference between intravitreal faricimab and anti-VEGF in BCVA [weighted mean difference (WMD) = 0.47; 95% CI: (- 0.17, 1.11)]. The intravitreal faricimab group showed numerically lower CST [WMD =  - 5.96; 95% CI = (- 7.11, - 4.82)], total CNV area [WMD =  - 0.49; 95% CI = (- 0.68, - 0.30)], and total lesion leakage [WMD =  - 0.88; 95% CI = (- 1.08, - 0.69)] after intravitreal therapy compared with the intravitreal anti-VEGF group. There were no statistically significant differences between intravitreal faricimab and anti-VEGF in ocular adverse events (AEs) [pooled odds ratio (OR) = 1.10; 95% CI = (0.81, 1.49)] and serious adverse events (SAEs) [pooled OR = 0.84; 95% CI = (0.37, 1.90)]. The intravitreal bispecific anti-VEGF/angiopoietin 2 (Ang2) antibody faricimab with a extended injection interval was non-inferior to first-line anti-VEGF agents in BCVA. It was safe and had better anatomical recovery. Large, well-designed RCTs are needed to explore the potential benefit of extended faricimab for nAMD. This systematic review was registered in the International Prospective Register of Systematic Reviews (PROSPERO) database (CRD42022327450).

Exploring the Spectrum of VEGF Inhibitors' Toxicities from Systemic to Intra-Vitreal Usage in Medical Practice

The use of Vascular Endothelial Growth Factor inhibitors (VEGFi) has become prevalent in the field of medicine, given the high incidence of various pathological conditions necessitating VEGF inhibition within the general population. These conditions encompass a range of advanced neoplasms, such as colorectal cancer, non-small cell lung cancer, renal cancer, ovarian cancer, and others, along with ocular diseases. The utilization of VEGFi is not without potential risks and adverse effects, requiring healthcare providers to be well-prepared for identification and management. VEGFi can be broadly categorized into two groups: antibodies or chimeric proteins that specifically target VEGF (bevacizumab, ramucirumab, aflibercept, ranibizumab, and brolucizumab) and non-selective and selective small molecules (sunitinib, sorafenib, cabozantinib, lenvatinib, regorafenib, etc.) designed to impede intracellular signaling of the VEGF receptor (RTKi, receptor tyrosine kinase inhibitors). The presentation and mechanisms of adverse effects resulting from VEGFi depend primarily on this distinction and the route of drug administration (systemic or intra-vitreal). This review provides a thorough examination of the causes, recognition, management, and preventive strategies for VEGFi toxicities with the goal of offering support to oncologists in both clinical practice and the design of clinical trials.

Advanced Technologies of Drug Delivery to the Posterior Eye Segment Targeting Angiogenesis and Ocular Cancer

Retinoblastoma (RB), a childhood retinal cancer is caused due to RB1 gene mutation which affects the child below 5 years of age. Angiogenesis has been proven its role in RB metastasis due to the presence of vascular endothelial growth factor (VEGF) in RB cells. Therefore, exploring angiogenic pathway by inhibiting VEGF in treating RB would pave the way for future treatment. In preclinical studies, anti-VEGF molecule have shown their efficacy in treating RB. However, treatment requires recurrent intra-vitreal injections causing various side effects along with patient nonadherence. As a result, delivery of anti-VEGF agent to retina requires an ocular delivery system that can transport it in a non-invasive manner to achieve patient compliance. Moreover, development of these type of systems are challenging due to the complicated physiological barriers of eye. Adopting a non-invasive or minimally invasive approach for delivery of anti-VEGF agents would not only address the bioavailability issues but also improve patient adherence to therapy overcoming the side effects associated with invasive approach. The present review focuses on the eye cancer, angiogenesis and various novel ocular drug delivery systems that can facilitate inhibition of VEGF in the posterior eye segment by overcoming the eye barriers.

Safety and efficacy profile of intravitreal ranibizumab vs dexamethasone in treatment of naïve diabetic macular edema

PURPOSE

To compare the safety and efficacy parameters of intravitreal ranibizumab vs intravitreal dexamethasone (IVD) in the treatment of patients with naïve diabetic macular edema (DME) in terms of best-corrected visual acuity (BCVA), central macular thickness (CMT), and possible complications like intraocular pressure (IOP) rise and cataract progression.

METHODS

A hospital-based prospective and comparative study of naïve DME patients was conducted between November 2020 and October 2021 with a minimum follow-up (F/U) period of 6 months. Thirty phakic patients received one dose of IVD implant (Group A) and the other 30 (Group B) received three consecutive monthly doses of ranibizumab. The main exclusion criteria were steroid responders and the presence of ocular inflammation.

RESULTS

The mean pre-injection CMT in Group A was 405µ and reduced to 297.07µ at 3 months and 278.35µ at 6 months. Mean increase in logMAR BCVA was 0.55. The mean pre-injection IOP was 16.28 and 17.64 mm of Hg at 6 months. In Group B, the mean pre-injection CMT was 401.07µ and reduced to 276.1µ at 3 months and 292.9µ at 6 months. Mean BCVA increased to 0.37. The mean pre-injection IOP was 17.28 mm Hg and 16.42 mm Hg at 6 months. There was no significant progression of cataract in both groups.

CONCLUSION

The mean decrease in CMT was comparable in both the groups at 6 months F/U with an improvement of BCVA with no significant IOP fluctuation or cataract progression. Hence, IVD appears to be noninferior to ranibizumab in the treatment of naïve DME.

Anti-VEGF Drugs in Age-Related Macular Degeneration: A Focus on Dosing Regimen-Related Safety and Efficacy

Age-related macular degeneration (AMD) is one of the main causes of visual impairment and severe visual loss, and can progress to two advanced forms-neovascularization and atrophic. The field of anti-AMD drugs has undergone huge developments in recent years, from single-target intravitreal administration to current clinical studies with multi-target and non-invasive agents, offering interesting new pharmacological opportunities for the treatment of this disease. Hence, we summarize some of the approved anti-vascular endothelial growth factor (VEGF) drugs for neovascular AMD, especially their structural characteristics, clinical manifestations, dosing regimens, and safety issues of the anti-VEGF drugs highlighted. In addition, advances in atrophic AMD drug research are also briefly described.

INTRAOCULAR INFLAMMATION INCIDENCE AFTER INTRAVITREAL BROLUCIZUMAB INJECTION FOR EXUDATIVE AGE-RELATED MACULAR DEGENERATION

PURPOSE

We evaluated the clinical outcomes of intraocular inflammation (IOI) of eyes with neovascular age-related macular degeneration (AMD) injected with brolucizumab in our tertiary referral center.

METHODS

A retrospective case series for which clinical records of all eyes that received intravitreal brolucizumab at Bascom Palmer Eye Institute between December 1, 2019, and April 1, 2021, were reviewed.

RESULTS

There were 345 eyes of 278 patients who received 801 brolucizumab injections. IOI was detected in 16 eyes of 13 patients (4.6%). In those patients, baseline Logarithm of Minimu Angle of Resolution (logMAR) best-corrected visual acuity was 0.32 0.2 (20/42), while it was 0.58 0.3 (20/76) at IOI presentation. The mean number of injections among eyes experiencing IOI was 2.4, and the interval between the last brolucizumab injection and IOI presentation was 20 days. There was no known case of retinal vasculitis. Management of IOI included topical steroids in seven eyes (54%), topical and systemic steroids in five eyes (38%), and observation in one eye (8%). Best-corrected visual acuity returned to baseline and inflammation resolved in all eyes by the last follow-up examination.

CONCLUSION

Intraocular inflammation after brolucizumab injection for neovascular AMD was not uncommon. Inflammation resolved in all eyes by the last follow-up visit.

Recent advances and prospects for lipid-based nanoparticles as drug carriers in the treatment of human retinal diseases

The delivery of cures for retinal diseases remains problematic. There are four main challenges: passing through multiple barriers of the eye, the delivery to particular retinal cell types, the capability to carry different forms of therapeutic cargo and long-term therapeutic efficacy. Lipid-based nanoparticles (LBNPs) are potent to overcome these challenges due to their unique merits: amphiphilic nanoarchitectures to pass biological barriers, vary modifications with specific affinity to target cell types, flexible capacity for large and mixed types of cargos and slow-release formulations for long-term treatment. We have reviewed the latest research on the applications of LBNPs for treating retinal diseases and categorized them by different payloads. Furthermore, we identified technical barriers and discussed possible future development for LBNPs to expand the therapeutic potential in treating retinal diseases.

Evaluating initial responses to brolucizumab in patients undergoing conventional anti-VEGF therapy for diabetic macular edema: a retrospective, single-center, observational study

Our retrospective, single-center, observational study aimed to evaluate the initial responses to intravitreal injection of brolucizumab (IVBr) in patients undergoing anti-vascular endothelial growth factor (VEGF) therapy for diabetic macular edema (DME). In total, 23 eyes of 20 patients with DME treated with at least one intravitreal injection of ranibizumab or aflibercept within one year and then switched to IVBr were included. Best corrected visual acuity (BCVA), central macular thickness (CMT), and macular volume (MV) on optical coherence tomography images were evaluated just before the most recent conventional anti-VEGF (ranibizumab/aflibercept) injection therapy (V1), one month after the most recent traditional anti-VEGF therapy (V2), just before the first IVBr (V3), and one month after the first IVBr (V4). BCVA, CMT, MV, and presence of intraocular inflammation (IOI) were evaluated at each visit. Anterior chamber flare values were also examined at V3 and V4. BCVA showed significant improvement at V2 (0.30 ± 0.23) than V1 (0.39 ± 0.29) and at V4 (0.34 ± 0.26) than V3 (0.48 ± 0.34) (P = 0.002, P < 0.001). However, no significant difference was observed between V2 and V4 (P = 0.257). CMT was significantly thinner at V2 (346.8 ± 90.2 µm) than V1 (495.5 ± 123.8 µm), and at V4 (322.2 ± 95.7 µm) than V3 (536.5 ± 166.0 µm) (P < 0.001, P < 0.001), but no significant difference was observed between V2 and V4 (P = 0.140). MV was significantly smaller at V2 (11.6 ± 2.0 mm³) than V1 (12.6 ± 1.9 mm³) and at V4 (11.2 ± 2.0 mm³) than V3 (12.6 ± 2.0 mm³) (P < 0.001, P < 0.001), and even significantly smaller at V4 than V2 (P = 0.009). No patient had IOI. No significant changes were observed in anterior chamber flare values between V3 and V4 (25.6 ± 14.6 vs. 24.0 ± 11.5 photon count/ms; P = 0.543). Both CMT and MV significantly reduced without any adverse events one month after switching from conventional anti-VEGF to IVBr therapy for DME, including IOI. MV was significantly lower for IVBr than anti-VEGF therapy after one month of treatment. Therefore, brolucizumab may be a viable treatment option for DME patients considering switching from conventional anti-VEGF agents for various reasons, such as poor response or inability to extend dosing intervals.

Production of a biosimilar version of aflibercept to improve VEGF blocker cytotoxicity on endothelial cells

This project aimed to produce a biosimilar version of aflibercept (AFL) and evaluate the effect of the co-treatment of AFL with other vascular endothelial growth factor (VEGF) blocker drugs. For this purpose, the optimized gene was inserted into the pCHO1.0 plasmid and transfected into the CHO-S cell line. The final concentration of biosimilar-AFL for the selected clone was 782 mg/L. Results revealed that the inhibition potential of the biosimilar-AFL on HUVEC cells was significant at 10 and 100 nM concentrations and in a dose-dependent manner. Furthermore, co-treatment of biosimilar-AFL with Everolimus (EVR), Lenvatinib (LEN), and Sorafenib (SOR) could reduce HUVEC cell viability/proliferation, more than when used alone. When LEN and SOR were co-treated with biosimilar-AFL, their cytotoxicity increased 10-fold. The most and least efficient combination was seen when biosimilar-AFL combined with LEN and EVR, respectively. Finally, biosimilar-AFL may improve the efficiency of LEN, EVR, and SOR in reducing the VEGF effect on endothelial cells.

A Novel Device for Suprachoroidal Drug Delivery to Retina: Evaluation in Nonhuman Primates

Purpose

Evaluation of distribution and tolerance of suprachoroidal injection of indocyanine green (ICG) in nonhuman primates (NHPs) using a novel suprachoroidal (SC) delivery technology.

Methods

Three live and three euthanized African green monkeys were injected with 150 or 200 µL ICG/eye into the SC space of both eyes, 2.5 mm posterior to the limbus in the inferior quadrant, utilizing a novel SC injector. Eyes were analyzed by imaging of scleral flatmounts. Live animals were observed for 24 hours for general health. Ophthalmic evaluation included slit-lamp biomicroscopy, tonometry, fundus imaging, confocal laser ophthalmoscopy, and spectral-domain optical coherence tomography (SD-OCT) before and at 10 minutes and 1, 3, and 24 hours post-injection.

Results

SC dosing was successfully performed in all eyes. Infrared fundus imaging demonstrated ICG distribution throughout the posterior segment, reaching the macula within 24 hours post-injection. No inflammation, intravitreal penetration, SC blebs, retinal detachment, or hemorrhages were detected. No significant changes were observed in retinal thickness by SD-OCT (P = 0.267, ANOVA). A mild, statistically insignificant elevation in intraocular pressure was observed within 10 minutes post-injection (mean ± standard error: 7.28 ± 5.09 mmHg; P = 0.061) and was spontaneously resolved within the first hour after dosing.

Conclusions

Suprachoroidal injection of 150 to 200 µL ICG dye was successfully performed and well tolerated in NHP eyes, with rapid distribution into the macular region and throughout the posterior pole.

Translational Relevance

This novel SC drug delivery system may potentially provide safe and effective delivery of therapeutics to the posterior pole region in humans.

The role of PLVAP in endothelial cells

Endothelial cells play a major part in the regulation of vascular permeability and angiogenesis. According to their duty to fit the needs of the underlying tissue, endothelial cells developed different subtypes with specific endothelial microdomains as caveolae, fenestrae and transendothelial channels which regulate nutrient exchange, leukocyte migration, and permeability. These microdomains can exhibit diaphragms that are formed by the endothelial cell-specific protein plasmalemma vesicle-associated protein (PLVAP), the only known protein component of these diaphragms. Several studies displayed an involvement of PLVAP in diseases as cancer, traumatic spinal cord injury, acute ischemic brain disease, transplant glomerulopathy, Norrie disease and diabetic retinopathy. Besides an upregulation of PLVAP expression within these diseases, pro-angiogenic or pro-inflammatory responses were observed. On the other hand, loss of PLVAP in knockout mice leads to premature mortality due to disrupted homeostasis. Generally, PLVAP is considered as a major factor influencing the permeability of endothelial cells and, finally, to be involved in the regulation of vascular permeability. Following these observations, PLVAP is debated as a novel therapeutic target with respect to the different vascular beds and tissues. In this review, we highlight the structure and functions of PLVAP in different endothelial types in health and disease.

The Effect of Dorzolamide-timolol Eye drop on Intraocular Pressure Change in Intravitreal Ranibizumab Injected Patients

PURPOSE

The objective of the study was to examine the effect of dorzolamide-timolol (DT) eye drop used before intravitreal ranibizumab (IVR) injection on intraocular pressure (IOP) change.

METHODS

50 eyes of 50 patients who received DT eye drops 1 h before IVR injection due to diabetic retinopathy and macular edema were considered Group 1, and 50 eyes of 50 patients who did not receive DT eye drops were considered Group 2. Those patients who had previously undergone intravitreal injection had intraocular surgery, and used any eye drops were not included in the study. Before the injection, IOP values were measured with a Tonopen contact handheld tonometer before the blepharostat was placed (BIOP), after the blepharostat was placed (AIOP), and at the 1st min after the injection (IIOP).

RESULTS

There were 25 males and 25 females in Group 1 and 25 males and 25 females in Group 2; the mean age was 65.66 ± 9.94 years in Group 1 and 65.54 ± 7.43 years in Group 2 (P = 0.98). In Group 1, BIOP was 18.91 ± 18.91, AIOP was 21.62 ± 6.16 mmHg, and IIOP was 49.21 ± 10.95 mmHg. In Group 2, BIOP was 20.18 ± 4.19 mmHg, AIOP was 24.60 ± 4.90 mmHg, and IIOP was 49.96 ± 9.72 mmHg. IIOP-BIOP difference was 30.30 ± 9.85 mmHg in Group 1 and 29.78 ± 9.33 mmHg in Group 2 and the difference was not statistically significant (P = 0.78). In Group 1, the IIOP-AIOP difference was 27.58 ± 10.60 mmHg and in Group 2, 25.36 ± 10.46 mmHg. The difference between IIOP and AIOP was not statistically significant (P = 0.27).

CONCLUSION

The use of topical DT eye drops before IVR injection does not affect the intraocular pressure change.

Retinal arterial occlusive vasculitis after multiple intravitreal brolucizumab injections for diabetic macular edema

Purpose

To describe a case of unilateral retinal arterial occlusive vasculitis after multiple intravitreal brolucizumab (IVBr) treatments for diabetic macular edema (DME).

Observations

A 68-year-old Japanese woman who had a 3-year history of insulin-dependent diabetes mellitus presented with decreased vision in the right eye (oculus dexter, OD). After two consecutive IVBr (3 mg) treatments for DME, spaced 6 weeks apart, her best corrected visual acuity improved from 20/32 to 20/28 OD, as central macular thickness (CMT) decreased from 368 μm to 253 μm on optical coherence tomography (OCT). Immediately after the 3rd IVBr, the right intraocular pressure (IOP) increased. One week later, iritis (aqueous flares: 65.0 photon count [PC]/ms) was observed, followed by localized vasculitis 2 weeks later. One month after the 3rd IVBr, extensive vasculitis and vasculitis occluding retinal arterioles were identified. Based on the history of IVBr use and clinical findings, intraocular inflammation (IOI) and subsequent retinal arterial occlusive vasculitis due to IVBr was diagnosed. Topical steroid administration (i.e., eye drops and subtenon injection) resulted in improvement of IOI after 3 months. She subsequently underwent two intravitreal aflibercept injections for DME and panretinal photocoagulation (PRP) to prevent the development of proliferative changes due to diabetic retinopathy. One year after the diagnosis of retinal arterial occlusive vasculitis, the patient had slight loss of vision (20/50) compared to baseline, due to the progression of cataracts, and OCT angiography (OCTA) showed extensive non-perfusion area on the temporal side. However, other examination findings (IOP: 16 mmHg, aqueous flares: 30.5 PC/ms, CMT: 283 μm) were stable.

Conclusions and importance

Diagnosis and treatment at a relatively early stage after the onset of IOI prevented severe visual impairment in this case. Topical betamethasone eye drops reduced anterior chamber inflammation associated with IVBr; however, vascular sheathing worsened when topical drops alone was used. Occlusive retinal vasculitis, diagnosed with fluorescein angiography (FA) and OCTA, appeared to stabilize when subtenon triamcinolone injection was added to topical steroid administration. Because the central macula was not involved, severe vision loss was prevented. It is unknown if topical steroid administration would be adequate to prevent worsening of occlusive vasculitis in other cases. Although not used in this case, oral prednisone is one treatment option that may prevent severe vision loss. However, it requires monitoring of side effects, such as elevated blood glucose levels. PRP is also an option in cases where progression of proliferative changes is a concern, as was done in this case. With these considerations in mind, it is important to diagnose brolucizumab-associated IOI and subsequent retinal arterial occlusive vasculitis in DME patients early and initiate treatment to prevent severe visual impairment. Diagnosing new IOI and subsequent retinal arterial occlusive vasculitis is more difficult in DME than in neovascular age-related macular degeneration because of the inflammatory component often associated vascular occlusions. Therefore, early IOI diagnosis and follow-up using various instruments such as laser flare cell meter, wide-field color imaging, OCT/OCTA, and FA, in addition to usual comprehensive ophthalmologic examinations, is crucial.

Design, construction and in vivo functional assessment of a hinge truncated sFLT01

Gene therapy for the treatment of ocular neovascularization has reached clinical trial phases. The AAV2-sFLT01 construct was already evaluated in a phase 1 open-label trial administered intravitreally to patients with advanced neovascular age-related macular degeneration. SFLT01 protein functions by binding to VEGF and PlGF molecules and inhibiting their activities simultaneously. It consists of human VEGFR1/Flt-1 (hVEGFR1), a polyglycine linker, and the Fc region of human IgG1. The IgG1 upper hinge region of the sFLT01 molecule makes it vulnerable to radical attacks and prone to causing immune reactions. This study pursued two goals: (i) minimizing the immunogenicity and vulnerability of the molecule by designing a truncated molecule called htsFLT01 (hinge truncated sFLT01) that lacked the IgG1 upper hinge and lacked 2 amino acids from the core hinge region; and (ii) investigating the structural and functional properties of the aforesaid chimeric molecule at different levels (in silico, in vitro, and in vivo). Molecular dynamics simulations and molecular mechanics energies combined with Poisson-Boltzmann and surface area continuum solvation calculations revealed comparable free energy of binding and binding affinity for sFLT01 and htsFLT01 to their cognate ligands. Conditioned media from human retinal pigment epithelial (hRPE) cells that expressed htsFLT01 significantly reduced tube formation in HUVECs. The AAV2-htsFLT01 virus suppressed vascular development in the eyes of newborn mice. The htsFLT01 gene construct is a novel anti-angiogenic tool with promising improvements compared to existing treatments.

Computational Modeling of Ophthalmic Procedures: Computational Modeling of Ophthalmic Procedures

PURPOSE

To explore how finite-element calculations can continue to contribute to diverse problems in ophthalmology and vision science, we describe our recent work on modeling the force on the peripheral retina in intravitreal injections and how that force increases with shorter, smaller gauge needles. We also present a calculation that determines the location and stress on a retinal pigment epithelial detachment during an intravitreal injection, the possibility that stress induced by the injection can lead to a tear of the retinal pigment epithelium.

BACKGROUND

Advanced computational models can provide a critical insight into the underlying physics in many surgical procedures, which may not be intuitive.

METHODS

The simulations were implemented using COMSOL Multiphysics. We compared the monkey retinal adhesive force of 18 Pa with the results of this study to quantify the maximum retinal stress that occurs during intravitreal injections.

CONCLUSIONS

Currently used 30-gauge needles produce stress on the retina during intravitreal injections that is only slightly below the limit that can create retinal tears. As retina specialists attempt to use smaller needles, the risk of complications may increase. In addition, we find that during an intravitreal injection, the stress on the retina in a pigment epithelial detachment occurs at the edge of the detachment (found clinically), and the stress is sufficient to tear the retina. These findings may guide physicians in future clinical research. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

Monoclonal Antibodies: A Therapeutic Option for the Treatment of Ophthalmic Diseases of the Eye Posterior Segment

The eye is an organ that allows us to observe the outside world. Pathologies of the eye's posterior segment, such as glaucoma, macular degeneration, diabetic retinopathy, uveitis, and retinoblastoma, cause vision loss. Traditional treatments consist of applying topical medications that do not penetrate properly or using high doses that generate adverse effects. Different laser surgeries stop the pathology's progression but do not allow visual improvement. So, an alternative is to use monoclonal antibodies, proteins produced by different processes that selectively bind to metabolites associated with diseases, reducing the adverse effects of traditional treatments and improving the application of the drug in the area. The two main molecular targets are TNF (adalimumab, infliximab, and certolizumab pegol) and VEGF (bevacizumab and ranibizumab); other possibilities are under investigation.

Appropriate dose of intravitreal ranibizumab for ROP: a retrospective study

Objective

To compare the recurrence rate of retinopathy of prematurity (ROP) after treatment with 0.3 mg vs. 0.25 mg ranibizumab.

Subjects

All patients with ROP who underwent intravitreal injection of ranibizumab in Hainan General Hospital between January 2014 and May 2020 were included in this retrospective study.

Methods

Eighty-two cases (146 eyes) who received intravitreal injection of 0.25 mg ranibizumab were included in the conventional-dose group, and 59 cases (108 eyes) who received intravitreal injection of 0.3 mg ranibizumab were included in the high-dose group. The two groups were further divided into the 25-28-week, 29-31-week, 32-34-week, and 35-36-week GA subgroups. The differences between the conventional-dose group and the high-dose group in gestational age (GA), birth weight (BW), age at initial injection (weeks), incidence of systemic diseases, the recurrence rate of ROP, and age at retinal vascularization completed (weeks) were analyzed.

Results

GA, BW, age at initial injection, and the incidence of systemic diseases were not significantly different between the conventional-dose group and the high-dose group (p > 0.05). The recurrence rates of ROP were significantly lower in the 25-28-week, 29-31-week, and 32-34-week subgroups of the high-dose group than in the same subgroups of the conventional-dose group (p < 0.05). Within the conventional-dose group, the recurrence rate of ROP was significantly lower in the 32-34-week and 35-36-week subgroups than in the 25-28-week and 29-31-week subgroups (p < 0.05). Within the high-dose group, the recurrence rate of ROP was not significantly different between the four subgroups (p > 0.05). Retinal vascularization was completed at a later age in the 32-34-week subgroup of the high-dose group than in the 32-34-week subgroup of the conventional-dose group (p < 0.05) but was not significantly different between the two groups at any other GA range (p > 0.05). No severe ocular or systemic complications occurred in any patient.

Conclusion

Treatment with 0.3 mg ranibizumab can reduce the recurrence rate of ROP without prolonging retinal vascularization or causing serious systemic complications. Therefore, this dose may be an appropriate therapeutic dose for ROP.

Effect of quadrant switch on ıntraocular pressure change in ıntravitreal aflibercept or ranibizumab ınjection applications

OBJECTIVE

To evaluate the effect of injection quadrant switch on the intraocular pressure (IOP) change in intravitreal aflibercept or ranibizumab applications.

METHODS

123 eyes of 123 patients who received intravitreal injection (IVE) into the superotemporal quadrant at least 10 times for age-related macular degeneration or diabetic macular edema have been recruited. The demographic data, lens status, IOP values (preoperative, postoperative 0th min, and postoperative 30th min), and amount of vitreous reflux (VR) following IVE have been recorded. Next IVE application was performed into the inferotemporal quadrant of the patient, which had never been injected before.

RESULTS

The mean IOP value at postoperative 0th min was 50.24 ± 7.66 mmHg after injections into the superotemporal quadrant and was 34.85 ± 4.96 mmHg after injections into the inferotemporal quadrant. No significant difference was observed between the preoperative and postoperative 30th min-IOP values (p > 0.05), while a significant difference was found between the postoperative 0th min-IOP values among quadrants (p < 0.001). VR was significantly higher in applications into the inferotemporal quadrant than those into the superotemporal quadrant (p < 0.001).

CONCLUSION

One of the most principal factors affecting the postoperative short-term IOP increase is the amount of VR, and this amount decreases the IOP following an IVE. The high amount of VR produced in the quadrant where the injection was applied for the first time caused a low-level IOP, while the low amount of VR formed in the quadrant where the repeated injections were applied caused a higher IOP.

CHANGES IN SYSTEMIC LEVELS OF VASCULAR ENDOTHELIAL GROWTH FACTOR AFTER INTRAVITREAL INJECTION OF AFLIBERCEPT OR BROLUCIZUMAB FOR NEOVASCULAR AGE-RELATED MACULAR DEGENERATION

PURPOSE

To analyze and compare the effects of intravitreal brolucizumab versus aflibercept on systemic vascular endothelial growth factor (VEGF)-A levels in patients with neovascular age-related macular degeneration.

METHODS

In this prospective interventional case series study, brolucizumab (6.0 mg/50 µL) or aflibercept (2.0 mg/50 µL) was injected intravitreally in 30 patients each. Blood samples were drawn at baseline and 7 days and 28 days after the first injection. Systemic VEGF-A levels were measured using enzyme-linked immunosorbent assay. Thirty healthy individuals served as controls.

RESULTS

The median baseline systemic VEGF-A levels in the brolucizumab, aflibercept, and control groups were 10.8 (8.0-13.2), 12.0 (8.0-18.5), and 10.0 (8.0-15.1) pg/mL, respectively (P = 0.315). In the brolucizumab group, VEGF-A levels significantly decreased to 8.0 (8.0-11.5) pg/mL on Day 7 (P = 0.0254) and to 8.0 (8.0-8.0) pg/mL on Day 28 (P < 0.001). In the aflibercept group, VEGF-A levels significantly decreased to 8.0 (8.0-8.0) pg/mL on Day 7 (P < 0.001) but returned to the baseline level, 12.5 (8.5-14.6) pg/mL, on Day 28 (P = 0.120). Vascular endothelial growth factor-A levels were significantly different between the treatment groups after 28 days (P < 0.001).

CONCLUSION

Intravitreal brolucizumab resulted in a sustained reduction of systemic VEGF-A levels until 28 days posttreatment, which raises concerns regarding its safety and long-term effects.

Discovering the Potential of Natural Antioxidants in Age-Related Macular Degeneration: A Review

Age-related macular degeneration (AMD) is a multifactorial disease associated with anatomical changes in the inner retina. Despite tremendous advances in clinical care, there is currently no cure for AMD. This review aims to evaluate the published literature on the therapeutic roles of natural antioxidants in AMD. A literature search of PubMed, Web of Science and Google Scholar for peer-reviewed articles published between 1 January 2011 and 31 October 2021 was undertaken. A total of 82 preclinical and 18 clinical studies were eligible for inclusion in this review. We identified active compounds, carotenoids, extracts and polysaccharides, flavonoids, formulations, vitamins and whole foods with potential therapeutic roles in AMD. We evaluated the integral cellular signaling pathways including the activation of antioxidant pathways and angiogenesis pathways orchestrating their mode of action. In conclusion, we examined the therapeutic roles of natural antioxidants in AMD which warrant further study for application in clinical practice. Our current understanding is that natural antioxidants have the potential to improve or halt the progression of AMD, and tailoring therapeutics to the specific disease stages may be the key to preventing irreversible vision loss.

Treatment results of nondamaging retinal laser therapy in diabetic macular edema

BACKGROUND

Subthreshold nondamaging retinal laser therapy (NRT) provides a greater safety profile than conventional laser methods, but more data is needed on the efficacy and safety of subthreshold NRT in diabetic macular edema.

PURPOSE

To evaluate the efficacy and safety of NRT for the treatment of clinically significant macular edema (CSME) that is partially responsive or resistant to intravitreal anti-vascular endothelial growth factor (anti-VEGF) treatment.

METHODS

This was a retrospective case series study. Fifty eyes of 38 diabetic patients with CSME previously treated with at least 6-monthly intravitreal bevacizumab injections with/without intravitreal Ozurdex therapy were evaluated. The patients received 577-nm yellow wavelength laser therapy with PASCAL laser system (Topcon Medical Laser Systems, Santa Clara, CA, USA). Best-corrected visual acuity (BCVA) and central subfield thickness (CST) were evaluated before and 1, 3, 6, 12 and 24 months after laser treatment.

RESULTS

Baseline mean CST was 368.06 ± 86.9 µm. The mean CST values at the 1-, 3-, 6-, 12-, and 24-month visits were 336.93 ± 79.8, 352.40 ± 113.5, 336.36 ± 109.3, 325.10 ± 104 µm, and 310.08 ± 84.7 µm, respectively. The mean CST decreased significantly at the first (p = 0.002) and second year visits (p < 0.001) when compared with pretreatment values. Although visual acuity was improved at the first year compared with baseline, this difference was not statistically significant (p = 0.03). There was no significant difference in visual acuities between pretreatment and posttreatment visits. During 24-month follow-up, while 37 eyes were treated with [mean: 5.7 ± 3.4 (1-14)] intravitreal anti-VEGF injections, 3 eyes were administered single-dose intravitreal steroids. Additional intravitreal injections were not required in 10 (20%) eyes.

CONCLUSION

NRT is effective by itself or in combination with anti-VEGF agents in diabetic macular edema that is partially responsive or resistant to previous intravitreal injections. T role in treating this disorder should be assessed in more detail with prospective controlled studies.

Transient central retina artery occlusion in patients undergone intravitreal anti-vascular endothelial growth factor injections

PURPOSE

To evaluate the occurrence of transient central retinal artery occlusion following intravitreal anti-vascular endothelial growth factor injection.

METHODS

Prospective, observational study of 807 patients (807 eyes) who were given intravitreal injections of ranibizumab or aflibercept to treat any cause of retinal vascular diseases between 1 January 2017 and 30 November 2018 at the Federal Fluminense University Hospital in Niteroi, and a private facility in Rio de Janeiro, Brazil. Patients who did not present transient central retinal artery occlusion were excluded.

RESULTS

Among 4069 injections, only 18 patients (0.44%) presented transient central retinal artery occlusion, 14 mild cases (77.7%), and 4 severe cases (22.3%). The clinical factors associated with more severe cases of transient central retinal artery occlusion were the duration of the transient central retinal artery occlusion (p = 0.001), number of prior injections (p = 0.01), and a positive carotid Doppler test (p = 0.01). Twelve cases (66.6%) had positive carotid artery obstruction (atheroma plaque size ≥70%) while 6 cases (33.3%) had negative carotid artery obstruction (atheroma plaque size <70%). The age group >60 years old (p = 0.06), cup/disc ratio >0.6 (p = 0.06), and pseudophakic lens status were also factors with association with transient central retinal artery occlusion, although did not meet criteria for statistical significance. The only patient who experienced a recurrent episode of transient central retinal artery occlusion had diabetic macular edema, positive carotid Doppler test, and cup/optic disc ratio >0.6.

CONCLUSION

Transient central retinal artery occlusion is a rare adverse event that can appear in patients with retinal vascular disease receiving anti-vascular endothelial growth factor therapy. The atheroma plaque size and the number of prior injections can be associated with the severity of the event.

Risk factors for emerging intraocular inflammation after intravitreal brolucizumab injection for age-related macular degeneration

Purpose

To analyze the risk factors associated with emerging intraocular inflammation (IOI) after intravitreal brolucizumab injection (IVBr) to treat age-related macular degeneration (AMD).

Methods

This study included 93 eyes of 90 patients. The incidence of emerging IOI was analyzed. The patients were classified into IOI or non-IOI groups, and background clinical characteristics in each group were compared.

Results

IOI occurred in 14 eyes of 14 cases (16%; five women, nine men [5:9]; IOI group) after IVBr; contrastingly, no IOI occurred in 76 patients (10 women, 66 men [10:66]; non-IOI group). The mean ages in IOI and non-IOI groups were 79.4 ± 8.1 and 73.8 ± 8.9 years old, respectively, and the average age in the IOI group was significantly higher than that in the non-IOI group (P = 0.0425). In addition, the percentages of females in the IOI and non-IOI groups were 43% and 13%, respectively, and IOI occurred predominantly in females (odds ratio: 4.95, P = 0.0076). Moreover, the prevalence of diabetes in the IOI and non-IOI groups was 64% and 32%, respectively, with a significant difference (odds ratio: 3.90, P = 0.0196). In contrast, the prevalence of hypertension in the IOI and non-IOI groups was 36% and 57%, respectively, with no significant difference (P = 0.15).

Conclusion

The comparison of clinical profiles of IOI or non-IOI cases in IVBr treatment for AMD suggests that the risk factors for IOI are old age, female sex, and history of diabetes; however, IOI with vasculitis or vascular occlusion in this cohort does not seem to cause severe visual impairment. Further studies are required to investigate potential risk factors for IOI.

Suprachoroidal delivery of bevacizumab in rabbit in vivo eyes: Rapid distribution throughout the posterior segment

PURPOSE

To test the in-vivo bio-distribution and safety of bevacizumab delivery into the suprachoroidal space (SCS) using a novel injection system in a large eye model.

METHODS

Bevacizumab (1.25 mg) was injected into the vitreous (IVT, 50 µL, n = 12) or the SCS, (150 µL, n = 37) of live rabbits. Immunofluorescence and ELISA were used to assess bevacizumab distribution. Intraocular pressure (IOP) measurements, SD-OCT and fundus imaging, electroretinogram, and histology analysis were performed for safety assessment.

RESULTS

Bevacizumab was observed throughout the choroid layers up to the retinal pigment epithelium (RPE), within 1 h following SCS injection. The C_max of bevacizumab in the retina/choroid was 1043 ± 597 μg/gr tissue (mean ± standard error), 40-fold higher than in IVT injected eyes (p = 0.0339). One day following SCS injection, bevacizumab was detected throughout the posterior pole with a two-fold lower concentration. One week post-SCS injection, bevacizumab concentration in the retina/choroid dropped to 2.36 ± 1.32 μg/gr tissue (p = 0.034 vs. 1 h), with a half-life of 20 h. No suprachoroidal blebs, retinal detachment, hemorrhages, inflammation or changes in retinal function were observed up to 2 months following SCS injection. Elevated IOP (+16 mmHg) was observed two minutes post-SCS injection and spontaneously returned to baseline levels within 10 minutes.

CONCLUSIONS

The novel injection system enabled a minimally invasive, safe, and consistent delivery of bevacizumab with rapid distribution throughout the choroid layers up to the RPE in large eyes. Large volumes of anti-angiogenic are delivered in close proximity to the retina due to the high volume distribution.

The IL-23/IL-17 axis promotes the formation of retinal neovascularization by activating the NLRP3 inflammasome in macrophages in an experimental retinopathy mouse model

Retinal neovascularization (RNV), a pathological process shared among diabetic retinopathy, retinopathy of prematurity and other retinopathies, has been widely studied, but the mechanism remains unclear. In this study, the mechanism by which the interleukin (IL)-23/IL-17 axis regulates RNV in oxygen-induced retinopathy (OIR) model mice and in cell experiments in vitro was characterized. In the retinas of OIR mice, IL-23/IL-17 axis activation was increased and regulated RNV formation, and this effect was accompanied by increased macrophage recruitment and nucleotide-binding domain leucine-rich repeat and pyrin domain containing receptor 3 (NLRP3) inflammasome activation. Moreover, inhibiting the IL-23/IL-17 axis reduced the number of macrophage and the expression and activation of NLRP3 inflammasome. On the other hand, recombinant (r) IL-23p19 and rIL-17A promoted the expression and activation of NLRP3 inflammasome, and the proliferation and migration of macrophages. Furthermore, macrophage elimination decreased the activation of IL-23/IL-17 axis and the expression and activation of NLRP3 inflammasome. In summary, our experiments showed that the IL-23/IL-17 axis promoted the formation of RNV by activating the NLRP3 inflammasome in retinal macrophages of an OIR mouse model.

RGD-modified multifunctional nanoparticles encapsulating salvianolic acid A for targeted treatment of choroidal neovascularization

Background

The development of alternative anti-angiogenesis therapy for choroidal neovascularization (CNV) remains a great challenge. Nanoparticle systems have emerged as a new form of drug delivery in ocular diseases. Here, we report the construction and characterization of arginine-glycine-aspartic acid (RGD)-conjugated polyethyleneimine (PEI) as a vehicle to load antioxidant salvianolic acid A (SAA) for targeted anti-angiogenesis therapy of CNV. In this study, PEI was consecutively modified with polyethylene glycol (PEG) conjugated RGD segments, 3-(4′-hydroxyphenyl) propionic acid-Osu (HPAO), and fluorescein isothiocyanate (FI), followed by acetylation of the remaining PEI surface amines to generate the multifunctional PEI vehicle PEI.NHAc-FI-HPAO-(PEG-RGD) (for short, RGD-PEI). The formed RGD-PEI was utilized as an effective vehicle platform to load SAA.

Results

We showed that RGD-PEI/SAA complexes displayed desirable water dispersibility, low cytotoxicity, and sustainable release of SAA under different pH conditions. It could be specifically taken up by retinal pigment epithelium (RPE) cells which highly expressed ɑ_vβ₅ integrin receptors in vitro and selectively accumulated in CNV lesions in vivo. Moreover, the complexes displayed specific therapeutic efficacy in a mouse model of laser induced CNV, and the slow elimination of the complexes in the vitreous cavity was verified by SPECT imaging after ¹³¹I radiolabeling. The histological examinations further confirmed the biocompatibility of RGD-PEI/SAA.

Conclusions

The results suggest that the designed RGD-PEI/SAA complexes may be a potential alternative anti-angiogenesis therapy for posterior ocular neovascular diseases.

Graphic abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-021-00939-9.

80 Years of vision: preventing blindness from retinopathy of prematurity

Retinopathy of prematurity (ROP) is one of the leading yet preventable causes of childhood blindness worldwide. The purpose of this review is to provide a practical template for observational and treatment methods in order to reduce the overall incidence of any ROP and to improve both short-term and long-term outcomes once Type 1 ROP (treatable ROP) develops.

Drug-related adverse effects of antivascular endothelial growth factor agents

PURPOSE OF REVIEW

Antivascular endothelial growth factor (VEGF) agents have provided historic therapeutic breakthroughs in the treatment of retinal disease. New anti-VEGF agents are emerging for the treatment of retinal vascular diseases. Both systemic and ocular adverse effect need to be understood in managing patients. This review aims to highlight the adverse effects seen with routine use of bevacizumab, ranibizumab and aflibercept, as well as with new medications such as brolucizumab and abicipar.

RECENT FINDINGS

We review the recent findings of intraocular inflammation (IOI) of brolucizumab and abicipar in the context of the efficacy and safety reported with the routine anti-VEGF agents. Specifically, brolucizumab has been reported to cause occlusive retinal vasculitis in the setting of IOI, which has not been seen in other anti-VEGF medications. In addition, abicipar appears to cause IOI at a higher rate of patients than other anti-VEGF agents have previously.

SUMMARY

Newer anti-VEGF agents pose a significant risk of adverse events not seen with routine anti-VEGF agents.

Anti-VEGF-Resistant Retinal Diseases: A Review of the Latest Treatment Options

Anti-vascular endothelial growth factor (anti-VEGF) therapy currently plays a central role in the treatment of numerous retinal diseases, most notably exudative age-related macular degeneration (eAMD), diabetic retinopathy and retinal vein occlusions. While offering significant functional and anatomic benefits in most patients, there exists a subset of 15–40% of eyes that fail to respond or only partially respond. For these cases, various treatment options have been explored with a range of outcomes. These options include steroid injections, laser treatment (both thermal therapy for retinal vascular diseases and photodynamic therapy for eAMD), abbreviated anti-VEGF treatment intervals, switching anti-VEGF agents and topical medications. In this article, we review the effectiveness of these treatment options along with a discussion of the current research into future directions for anti-VEGF-resistant eyes.

Assessment of a New Nanostructured Microemulsion System for Ocular Delivery of Sorafenib to Posterior Segment of the Eye

Eye drop formulations allowing topical treatment of retinal pathologies have long been sought as alternatives to intravitreal administration. This study aimed to assess whether a novel nanostructured microemulsions system (NaMESys) could be usefully employed to deliver sorafenib to the retina following topical instillation. NaMESys carrying 0.3% sorafenib (NaMESys-SOR) proved to be cytocompatible in vitro on rabbit corneal cells, and well-tolerated following b.i.d. ocular administration to rabbits during a 3-month study. In rats subject to retinal ischemia-reperfusion, NaMESys-SOR significantly inhibited retinal expression of tumor necrosis factor-alpha (TNFα, 20.7%) and inducible nitric oxide synthase (iNos, 87.3%) mRNAs in comparison to controls. Similarly, in streptozotocin-induced diabetic rats, NaMESys-SOR inhibited retinal expression of nuclear factor kappa B (NFκB), TNFα, insulin like growth factor 1 (IGF1), IGF1 receptor (IGF1R), vascular endothelial growth factor receptor 1 (VEGFR1) and 2 (VEGFR2) mRNAs by three-fold on average compared to controls. Furthermore, a reduction in TNFα, VEGFR1 and VEGFR2 protein expression was observed by western blot. Moreover, in mice subject to laser-induced choroidal neovascularization, NaMESys-SOR significantly inhibited neovascular lesions by 54%. In conclusion, NaMESys-SOR was shown to be a well-tolerated ophthalmic formulation able to deliver effective amounts of sorafenib to the retina, reducing proinflammatory and pro-angiogenic mediators in reliable models of proliferative retinopathies. These findings warrant further investigations on the full therapeutic potential of NaMESys-SOR eye drops, aiming to address unmet needs in the pharmacotherapy of retinal neovascular diseases.

Real-World Safety Outcomes of Intravitreal Ranibizumab Biosimilar (Razumab) Therapy for Chorioretinal Diseases

Introduction

To assess the safety profile of the intravitreal ranibizumab biosimilar molecule, Razumab^® (Intas Pharmaceuticals, Ahmedabad, India) in chorioretinal disorders under real-world conditions.

Methods

This was a multicenter, retrospective chart review which included patients from 15 centers receiving intravitreal Razumab (IVRz) injections from 2016 to 2020. Patient demographics, ocular examination data, and detailed safety information regarding serious adverse events (SAE) or serious adverse drug reactions (sADR), and non-serious AEs (nsAE) or non-serious ADRs (nsADR) occurring within 1 month of IVRz injections were compiled.

Results

A total of 6404 eyes of 6404 patients received 9406 IVRz injections [mean (± SD) = 1.49 (± 0.63)] during 4.25 years. Adverse events were reported after 1978 injections (21.03%): 64.16% nsAE, 32.96% nsADR, 2.37% sADR, and 0.51% SAE. The most frequent adverse events were subconjunctival hemorrhage (8.2% of total injections), transient blurring of vision (6.5% of total injections), and mild ocular pain (5.27% of total injections). Serious ocular (31 cases with retinal pigment epithelial tears [0.33%], two cases of non-infectious vitritis [0.02%], and one case of endophthalmitis [0.01%]) and systemic (seven patients with non-fatal myocardial infarction [0.12%] and six patients with non-fatal cerebrovascular accident [0.09%]) adverse events were infrequent.

Conclusion

The study reports the largest pooled safety data on IVRz use in a real-world scenario. The results did not raise any new ocular or systemic safety concerns for the biosimilar agent, with the incidence and spectrum of adverse reactions similar to those reported with other anti-vascular endothelial growth factor (anti-VEGF) drugs. The real-world evidence suggests that IVRz is a safe anti-VEGF agent in the management of chorioretinal disorders.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40123-021-00345-2.

Assessment of the retinal and choroidal microvascularization in polycystic ovary syndrome: an optical coherence tomography angiography study

PURPOSE

To examine the retinal, peripapillary, choroidal microvascularization and the choroid thickness (CT) of the patients with polycystic ovary syndrome (PCOS) using optical coherence tomography angiography (OCT-A) and compare the results to measurements obtained from healthy controls.

METHODS

In total, 47 eyes of 47 patients recently diagnosed with PCOS and 47 eyes of 47 age-matched healthy women were included in this study. An RT XR Avanti instrument with AngioVue software was used for the OCT-A imaging using 6 × 6 mm macular and 4.5 × 4.5 mm optic nerve head scans. Quantitative vessel density results of superficial capillary plexus (SCP), deep capillary plexus (DCP) and radial peripapillary capillaries (RPC); flow area and flow density of choriocapillaris; and foveal avascular zone (FAZ) area were analyzed. CT was evaluated by using the measurements obtained from the subfoveolar area.

RESULTS

No significant differences were detected between the groups for any of vessel density results for the SCP, DCP, and RPC as well as the FAZ area. The difference in the choriocapillaris flow area and flow density between the groups was not statistically significant. The choroid was significantly thicker in women with PCOS than in the healthy group (p = 0.002).

CONCLUSION

Retinal and choroidal microvascularization was comparable between the women who were evaluated early after diagnosed with PCOS and age-matched healthy controls. Choroid was found thicker in patients with PCOS than in healthy women. OCT-A, as a new and noninvasive imaging method, may help in understanding the effect of PCOS on the posterior segment of the eye.

Exosome-mediated delivery of an anti-angiogenic peptide inhibits pathological retinal angiogenesis

Background: Pathological angiogenesis is the hallmark of many vision-threatening diseases. Anti-VEGF is a primary treatment with substantial beneficial effects. However, such agents require frequent intravitreal injections. Our previous work established a method for effectively modifying exosomes (EXOs) for loading therapeutic peptides. Here, we used this system to load the anti-angiogenic peptide KV11, aiming to establish an EXO-based therapy strategy to suppress neovascularization in the retina.

Methods: Using an anchoring peptide, CP05, we linked KV11 to endothelial cell (EC) derived EXOs, yielding EXO_KV11. We tested the delivery efficiency of EXO_KV11 via two commonly used ocular injection methods: retro-orbital injection and intravitreal injection. Deploying an oxygen-induced retinopathy (OIR) model and a VEGF injection model, we tested the effects of EXO_KV11 on neovascular formation, EC proliferation, and vascular permeability. In vitro experiments were used to test the mechanism and to analyze the effects of EXO_KV11 on EC proliferation, migration, and sprouting.

Results: By using the EXO loading system, KV11 was more efficiently delivered to the blood vessels of the mouse retina via retro-orbital injection. In both OIR model and VEGF injection model, EXO_KV11 was more effective than KV11 alone in inhibiting neovascularization and vessel leakage. The therapeutic effect of retro-orbital injection of EXO_KV11 was comparable to the intravitreal injection of VEGF-trap. Mechanistically, KV11 alone inhibited VEGF-downstream signaling, while EXO_KV11 showed a stronger effect.

Conclusions: We used EXOs as a carrier for intraocular delivery of KV11. We showed that KV11 itself has an anti-angiogenic effect through retro-orbital injection, but that this effect was greatly enhanced when delivered with EXOs. Thus, this system has the potential to treat proliferative retinopathy via retro-orbital injection which is a less invasive manner compared with intravitreal injection.

Non-invasive multimodal imaging of Diabetic Retinopathy: A survey on treatment methods and Nanotheranostics

Diabetes Retinopathy (DR) is one of the most prominent microvascular complications of diabetes. It is one of the pre-eminent causes for vision impairment followed by blindness among the working-age population worldwide. The de facto cause for DR remains challenging, despite several efforts made to unveil the mechanism underlying the pathology of DR. There is quite less availability of the low cost pre-emptive theranostic imaging tools in terms of in-depth resolution, due to the multiple factors involved in the etiology of DR. This review work comprehensively explores the various reports and research works on all perspectives of diabetic retinopathy (DR), and its mechanism. It also discusses various advanced non-destructive imaging modalities, current, and future treatment approaches. Further, the application of various nanoparticle-based drug delivery strategies used for the treatment of DR are also discussed. In a nutshell, the present review work bolsters the pursuit of the development of an advanced non-invasive optical imaging modal with a nano-theranostic approach for the future diagnosis and treatment of DR and its associated ocular complications.

Therapeutic measures for sulfur mustard-induced ocular injury

The use of sulfur mustard (SM) in global terrorism is still a relevant threat to both civilian population and military personnel. Casualties exposed to SM may present mild, moderate or severe acute ocular lesions followed by a complete ocular resolution, chronic lesions or re-emerged ocular pathologies after a latent period. Current treatment for SM-induced ocular injury is based mainly on the clinical manifestation at the different stages of the injury and includes pharmaceutical and surgical interventions. These therapeutic measures are beneficial but not sufficient, and the ocular injury remains a continuous challenge for medical professionals. This review focuses on treatment experience carried out in humans and studied in animal models, for both SM-induced ocular acute injury and late pathology. In general, therapeutic measures are based on clinical features of the ocular injury or on the involvement of specific factors during the ocular injury that point out towards potential treatments. Anti-inflammatory treatments and limbal stem cell transplantation techniques were developed based on the clinical manifestation of the ocular injury. Optional therapies for impaired corneal innervation and endothelium are suggested for future research. Additionally, studies on potential treatments with anti-matrix metalloproteinase (MMP), anti-vascular endothelial growth factor (VEGF) and anti-IL-6 agents are discussed. Consequently, future studies may reveal the potential of additional pharmacological and biological treatments or advanced cellular and molecular biology methods to serve as novel therapeutic measures and techniques for this complicated ocular injury.

Lymphocytic microparticles suppress retinal angiogenesis via targeting Müller cells in the ischemic retinopathy mouse model

Retinopathy of prematurity (ROP) is the primary cause of visual impairment and vision loss in premature infants, which results from the formation of aberrant retinal neovascularization (NV). An emerging body of evidence has shown that Müller cells are the predominant source of vascular endothelial growth factor (VEGF), which also serves as a chemoattractant for monocyte/macrophage lineage. The recruitment of macrophages is increased during retinal NV, and they exert a pro-angiogenic role in ROP. We have shown that lymphocytic microparticles (microvesicles; LMPs) derived from apoptotic human T lymphocytes possess strong angiogenesis-inhibiting properties. Here, we investigated the effect of LMPs on the chemotactic capacity of Müller cells in vitro using rat Müller cell rMC-1 and mouse macrophage RAW 264.7. In addition, the impact of LMPs was determined in vivo using a mouse model of oxygen-induced ischemic retinopathy (OIR). The results revealed that LMPs were internalized by rMC-1 and reduced their cell proliferation dose-dependently without inducing cell apoptosis. LMPs inhibited the chemotactic capacity of rMC-1 on RAW 264.7 via reducing the expression of VEGF. Moreover, LMPs attenuated pathological retinal NV and the infiltration of macrophages in vivo. LMPs downregulated ERK1/2 and HIF-1α both in vitro and in vivo. These findings expand our understanding of the effects of LMPs, providing evidence of LMPs as a promising therapeutic approach for the treatment of retinal NV diseases.

Inhibiting NF-κB Signaling Activation Reduces Retinal Neovascularization by Promoting a Polarization Shift in Macrophages

Purpose

Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling is involved in regulating tumor angiogenesis and metastasis; however, the exact mechanism of action in retinal neovascularization (RNV) remains unclear. The purpose of this study was to determine the role and underlying mechanism of NF-κB in regulating RNV in retinal neovascularization mice.

Methods

Expression levels of NF-κB signaling were detected by immunofluorescence staining and western blotting in retinas of oxygen-induced retinopathy (OIR) mice. OIR mice were treated with either pyrrolidinedithiocarbamate (PDTC), a NF-κB signaling inhibitor, or PBS, and retinal flat-mounts were performed to quantify the area of RNV and the recruitment of retinal macrophages by immunofluorescence staining. Macrophage polarization detected by flow cytometric analysis and the expression of macrophage polarization-associated genes were evaluated by immunofluorescence staining, quantitative RT-PCR, and western blotting.

Results

Expression levels of phosphorylated IκBα (p-IκBα) and p-p65 increased in OIR mice. Inhibiting NF-κB signaling activation by PDTC significantly reduced RNV. After treatment with PDTC, a reduction in the quantity of macrophages was observed: M1 polarized macrophages decreased, and M2 polarized macrophages increased; the expression of M1 macrophage-associated cytokines decreased and M2 macrophage-associated cytokines increased in the retinas of OIR mice.

Conclusions

Blocking activation of NF-κB signaling reduces RNV by promoting polarization of M1 macrophages to M2 macrophages in OIR mice.

The Diagnosis and Treatment of Age-Related Macular Degeneration

BACKGROUND

Age-related macular degeneration (AMD) is thought to cause approximately 9% of all cases of blindness worldwide. In Germany, half of all cases of blindness and high-grade visual impairment are due to AMD. In this review, the main risk factors, clinical manifestations, and treatments of this disease are presented.

METHODS

This review is based on pertinent publications retrieved by a selective search in PubMed for original articles and reviews, as well as on current position statements by the relevant specialty societies.

RESULTS

AMD is subdivided into early, intermediate, and late stages. The early stage is often asymptomatic; patients in the other two stages often have distorted vision or central visual field defects. The main risk factors are age, genetic predisposition, and nicotine consumption. The number of persons with early AMD in Germany rose from 5.7 million in 2002 to ca. 7 million in 2017. Late AMD is subdivided into the dry late form of the disease, for which there is no treatment at present, and the exudative late form, which can be treated with the intravitreal injection of VEGF inhibitors.

CONCLUSION

More research is needed on the dry late form of AMD in particular, which is currently untreatable. The treatment of the exudative late form with VEGF inhibitors is labor-intensive and requires a close collaboration of the patient, the ophthalmologist, and the primary care physician.

Risk of Inflammation, Retinal Vasculitis, and Retinal Occlusion-Related Events with Brolucizumab: Post Hoc Review of HAWK and HARRIER

PURPOSE

An independent Safety Review Committee (SRC), supported by Novartis Pharma AG, analyzed investigator-reported cases of intraocular inflammation (IOI), endophthalmitis, and retinal arterial occlusion in the phase 3 HAWK and HARRIER trials of brolucizumab versus aflibercept in neovascular age-related macular degeneration (nAMD).

DESIGN

A post hoc analysis of a subset of data from two 2-year, double-masked, multicenter, active-controlled randomized phase 3 trials (NCT02307682, NCT02434328).

PARTICIPANTS

Patients (N = 1817) with untreated, active choroidal neovascularization due to age-related macular degeneration in the study eye were randomized and treated in HAWK/HARRIER. The SRC reviewed data from cases of investigator-reported IOI (60/1088 brolucizumab-treated eyes; 8/729 aflibercept-treated eyes).

METHODS

The SRC received details and images (color fundus photography, fluorescein angiography, and OCT) for all investigator-determined cases of IOI, retinal arterial occlusion, and endophthalmitis. Cases were reviewed in detail by ≥2 readers, then adjudicated by the SRC as a group.

MAIN OUTCOME MEASURES

Within this patient subset: incidence of IOI, signs and incidence of retinal vasculitis and/or retinal vascular occlusion, and visual acuity loss; time since first brolucizumab injection to IOI event onset; and frequency of visual acuity loss after brolucizumab injection by time of first IOI event onset.

RESULTS

Fifty brolucizumab-treated eyes were considered to have definite/probable drug-related events within the spectrum of IOI, retinal vasculitis, and/or vascular occlusion. On the basis of these cases, incidence of definite/probable IOI was 4.6% (IOI + vasculitis, 3.3%; IOI + vasculitis + occlusion, 2.1%). There were 8 cases (incidence 0.74%) of at least moderate visual acuity loss (≥15 ETDRS letters) in eyes with IOI (7 in eyes with IOI + vasculitis + occlusion). Of the 8 cases, 5 experienced their first IOI-related event within 3 months of the first brolucizumab injection (increasing to 7/8 within 6 months). Incidence of IOI in aflibercept-treated eyes was 1.1%, with at least moderate visual acuity loss in 0.14%.

CONCLUSIONS

This analysis of IOI cases after brolucizumab injection identified signs of retinal vasculitis with or without retinal vascular occlusion and an associated risk of visual acuity loss. The findings will help physicians to evaluate the risks and benefits of brolucizumab treatment for nAMD.

Biomechanical properties of the cornea following intravitreal ranibizumab injection

OBJECTIVE

To evaluate intraocular pressure (IOP) and corneal biomechanical properties changes after intravitreal ranibizumab injection (IVRI).

METHODS

One hundred twenty eyes of 120 patients who underwent IVRI between January and March 2018 in Adnan Menderes University Ophthalmology Clinic were included in study. Corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated intraocular pressure (IOPg), and corneal-compensated intraocular pressure (IOPcc) were measured by Ocular Response Analyzer (ORA) by the same specialist preoperatively (preop), postoperative 1st (postop-1st), postoperative 3rd (postop-3rd), and postoperative 24th hours (postop-24th) after single-dose IVRI.

RESULTS

Among the 120 wet age-related macular degeneration subjects, 58 (48.3%) were female and 62 (51.7%) were male. The mean age was 64.8 ± 10.4 years. Postop-1st hour IOP cc and IOPg measurements were statistically different from all other measurements (p < 0.001). Postop-1st hour CH measurements were statistically different from preop and postop-3rd (p = 0.022 and p = 0.008, respectively).

CONCLUSION

After intravitreal injection, IOP pressures significantly increased. But, CH and CRF values were significantly decreased. All these changes were temporary.

Inhibiting the NLRP3 inflammasome with MCC950 ameliorates retinal neovascularization and leakage by reversing the IL-1β/IL-18 activation pattern in an oxygen-induced ischemic retinopathy mouse model

Activation of the nucleotide-binding domain leucine-rich repeat and pyrin domain containing receptor 3 (NLRP3) inflammasome plays an important role in ocular neovascularization. In our study, we found that the expression and activation levels of NLRP3 inflammasome components, including NLRP3, an apoptosis-associated speck-like protein (ASC) containing caspase activation and recruitment domain (CARD) and caspase-1 (CAS1), were significantly upregulated. In addition, we found interleukin (IL)-1β activity increased while IL-18 activity decreased in the retinas of oxygen-induced ischemic retinopathy (OIR) mice. MCC950, an inhibitor of NLRP3, reversed the IL-1β/IL-18 activation pattern, inhibited the formation of retinal neovascularization (RNV), decreased the number of acellular capillaries and reduced leakage of retinal vessels. Moreover, MCC950 could regulate the expression of endothelial cell- and pericyte function-associated molecules, such as vascular endothelial growth factor (VEGF), VEGF receptor (VEGFR)1, VEGFR2, matrix metalloproteinase (MMP)2, MMP9, tissue inhibitor of metalloproteinases (TIMP)1, TIMP2, platelet-derived growth factor receptor-β (PDGFR-β), platelet-derived growth factor-B (PDGF-B), and angiopoietin2 (Ang2). In vitro, recombinant human (r)IL-18 and rIL-1β regulated the expression of endothelial cell- and pericyte function-associated molecules and the proliferation and migration of endothelial cells and pericytes. We therefore determined that inhibiting the NLRP3 inflammasome with MCC950 can regulate the function of endothelial cells and pericytes by reversing the IL-1β/IL-18 activation pattern to ameliorate RNV and leakage; thereby opening new avenues to treat RNV-associated ocular diseases.

Patient-Reported Complications after Intravitreal Injection and Their Predictive Factors

Purpose

The intravitreal injection (IVI) of pharmacologic agents is the most commonly performed ocular procedure and is associated with a host of complications. Most IVI-related complications data are derived from randomized controlled clinical trials, which report a high adverse event rate. The nature of these protocol-driven trials limit their applicability to the diverse circumstances seen in routine clinical practice. The goal of this study was to determine the prevalence of patient-reported IVI-related complications, their risk factors, and the manner in which patients sought treatment at a tertiary eye care center.

Design

Retrospective, institutional review board–approved study.

Participants

Forty-four thousand seven hundred thirty-four injections in 5318 unique patients at the Cleveland Clinic Cole Eye Institute from 2012 through 2016.

Methods

Intravitreal injection.

Main Outcome Measures

Complication occurrence within 15 days of injection.

Results

From 2012 through 2016, a total of 44734 injections were performed in 5318 unique patients. Overall, complication rates were low, representing 1.9% of all injections, with 1031 unique complications in 685 patients (12.9%). The most common minor complications, or those not requiring intervention, were irritation (n = 312) and subconjunctival hemorrhage (n = 284). The most common serious complications, or those requiring intervention, were corneal abrasion (n = 46) and iritis (n = 31). Most complications (66%) were managed adequately by a telephone or Epic (Epic Systems Corp., Verona, WI) electronic message encounter only. Importantly, no injection protocol parameter, such as type of anesthesia, preparation, or post-injection medication, increased the risk of a complication. However, a patient’s gender, age, number of previous injections, and provider strongly influenced the risk of patient-reported complications.

Conclusions

Overall, complication rates seen in routine clinical practice were low compared with clinical trial reporting. Providers should feel confident in the safety and administration of IVI during times when follow-up office visits and resources may be limited. When performing an IVI, factors such as a patient’s gender, age, number of previous injections, and provider must be taken into account to ensure the best possible outcomes.