Development of ranibizumab, an anti-vascular endothelial growth factor antigen binding fragment, as therapy for neovascular age-related macular degeneration

Usability of the SB11 Pre-filled Syringe (PFS) in Patients with Retinal Diseases

INTRODUCTION

SB11 (Byooviz™; Samsung Bioepis Co., Ltd.) is a ranibizumab (Lucentis®; Genentech, Inc.) biosimilar targeting vascular endothelial growth factor A for the treatment of retinal diseases. The pre-filled syringe (PFS) presentation of SB11 offers an alternative administration method to the vial, with the potential for enhanced safety and efficient syringe preparation. The objective of this study was to assess the ability of healthcare professionals (HCPs) to follow the instructions for use to prepare and administer SB11 PFS intravitreal (IVT) injections to patients with neovascular age-related macular degeneration (nAMD) or macular edema secondary to retinal vein occlusion (RVO).

METHODS

This study was an open-label, single-arm, single-dose clinical study to evaluate the usability of the SB11 PFS in patients with nAMD or macular edema secondary to RVO. Four HCPs prepared and administered 0.5 mg SB11 PFS IVT injections to 34 patients. Product use task completion (12 tasks in total) was assessed by independent observers. Safety was assessed up to 7 days after injection of the investigational product.

RESULTS

A total of 34 patients were enrolled and completed the study. All 12 tasks were successfully completed in 34 (100%) patients without a use-related failure. Most patients (32 patients, 94.1%) experienced no adverse events (AEs), whereas 2 (5.9%) patients experienced three treatment-emergent AEs (TEAEs) which were mild to moderate in severity. There were no severe or serious TEAEs reported during the study.

CONCLUSIONS

This study showed that HCPs were able to successfully prepare and administer the SB11 PFS via IVT injection. No unexpected safety issues were identified. The SB11 PFS is a promising alternative for therapeutic administration of SB11 in patients with retinal disease.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT06176963; EudraCT number 2021-003566-12.

Cell and molecular targeted therapies for diabetic retinopathy

Diabetic retinopathy (DR) stands as a prevalent complication in the eye resulting from diabetes mellitus, predominantly associated with high blood sugar levels and hypertension as individuals age. DR is a severe microvascular complication of both type I and type II diabetes mellitus and the leading cause of vision impairment. The critical approach to combatting and halting the advancement of DR lies in effectively managing blood glucose and blood pressure levels in diabetic patients; however, this is seldom achieved. Both human and animal studies have revealed the intricate nature of this condition involving various cell types and molecules. Aside from photocoagulation, the sole therapy targeting VEGF molecules in the retina to prevent abnormal blood vessel growth is intravitreal anti-VEGF therapy. However, a substantial portion of cases, approximately 30-40%, do not respond to this treatment. This review explores distinctive pathophysiological phenomena of DR and identifiable cell types and molecules that could be targeted to mitigate the chronic changes occurring in the retina due to diabetes mellitus. Addressing the significant research gap in this domain is imperative to broaden the treatment options available for managing DR effectively.

[Anatomical and functional outcomes of the "3+PRN" therapeutic protocol in the treatment of diabetic macular edema]

PURPOSE

To evaluate the anatomical and functional results of the "3+PRN" protocol in the treatment of diabetic macular edema (DME), determine the predictive factors for good final visual acuity, and compare it to other protocols.

MATERIALS AND METHODS

We conducted a retrospective, descriptive, comparative, cross-sectional study of patients with DME, which we dubbed HTSM. All patients were treated with three monthly initial intravitreal injections (IVT) of 1.25mg bevacizumab and followed according to the pro re nata (PRN) protocol for a period of 3years. The protocol was based on a monthly monitoring schedule for the first 3months, then increasingly spaced out over time. "On-demand" treatment was indicated with resumption of bevacizumab IVT in the event of worsening of DME.

RESULTS

A total of 52 patients were included. The mean age was 65years. Type 2 was the most frequently observed type of diabetes. The mean duration of the PRN protocol was 6months, and the mean number of injections was 6. The mean visual acuity (VA), initially 1/10, improved to 3/10 by the conclusion of the 3+PRN protocol, with an improvement of more than 5 letters in 77.6% of cases. The mean initial central macular thickness (CMT) was 451.5μm. The final mean EMC decreased to 298.5μm, which corresponds to a reduction of 153μm compared to the initial value. The mean subfoveal choroidal thickness, initially 304.2μm, decreased to a mean of 284.5μm at completion. Comparative analysis of the results before and after the PRN protocol confirmed the existence of a statistically significant correlation between VA and CMT (P<0.05). No correlation was observed between age and visual acuity or between initial and final VA. The analysis of the various tomographic parameters and VA revealed a significantly better visual improvement in the group in whom the external limiting membrane (MLE) and ellipsoid zone (ZE) were intact (P=0.04), as well as in the group in whom serous retinal detachment (SRD) was absent (P<0.001). Posterior vitreous detachment (PVD) was the most frequently observed vitreomacular anomaly. The final VA was similar in the groups with and without PVD (P=0.04).

CONCLUSION

The 3+PRN protocol is effective both functionally and tomographically in the treatment of DME. Various tomographic parameters might influence therapeutic efficacy. However, further in-depth studies are needed to better investigate these parameters.

Association of baseline factors with 1-year outcomes in the SB11-ranibizumab equivalence trial: A post hoc analysis

PURPOSE

To identify baseline factors associated with 1-year outcomes when treating neovascular age-related macular degeneration (nAMD) with ranibizumab biosimilar SB11 or reference ranibizumab (rRBZ), and to compare efficacy of the two products within subgroups judged to be clinically relevant.

DESIGN

Post hoc analysis of a prospective, equivalence phase 3 randomized clinical trial (RCT) METHODS: 705 patients with nAMD were randomized 1:1 to receive SB11 or rRBZ for 48 weeks. Pooled and randomized groups were used to identify baseline factors associated with clinical outcomes at Week 52 using multiple linear regression models. Significant factors identified in regression analyses were confirmed in analyses of variance. Subgroup analyses comparing best-corrected visual acuity (BCVA) changes between SB11 and rRBZ were conducted.

RESULTS

634 (89.9%) participants completed the 52-week visit. Regression analyses showed that younger age, lower BCVA, and smaller total lesion area at baseline were associated with greater BCVA gain at Week 52, while older age, lower BCVA, and thicker central subfield thickness (CST) at baseline were predictors of greater CST reduction in the pooled group. Subgroup analyses demonstrated that BCVA outcomes appeared comparable for the SB11 and rRBZ groups.

CONCLUSION

Post hoc analyses of the SB11-rRBZ equivalence study showed that baseline age, BCVA, CST, and total lesion area were prognostic factors for visual or anatomical outcomes of nAMD, while subgroup analyses demonstrated comparable results for SB11 and rRBZ. Collectively, the results appear comparable to similar RCTs of anti-vascular endothelial growth factor reference products for nAMD and strengthen confidence in the biosimilarity of SB11.

Exploring Current Molecular Targets in the Treatment of Neovascular Age-Related Macular Degeneration toward the Perspective of Long-Term Agents

Long-lasting anti-vascular endothelial growth factor (anti-VEGF) agents have become an option to reduce treatment frequency, with ongoing research exploring optimal responses and safety profiles. This review delves into molecular targets, pharmacological aspects, and strategies for achieving effective and enduring disease control in neovascular age-related macular degeneration (AMD). The molecular pathways involved in macular neovascularization, including angiogenesis and arteriogenesis, are explored. VEGF, PlGF, Ang-1, and Ang-2 play crucial roles in regulating angiogenesis, influencing vessel growth, maturation, and stability. The complex interplay of these factors, along with growth factors like TGFβ and bFGF, contributes to the pathogenesis of neovascular membranes. Current anti-VEGF therapies, including bevacizumab, ranibizumab, aflibercept, brolucizumab, and faricimab, are discussed with a focus on their pharmacokinetics and clinical applications. Strategies to achieve sustained disease control in AMD involve smaller molecules, increased drug dosages, and novel formulations. This narrative review provides a comprehensive overview of the molecular targets and pharmacological aspects of neovascular AMD treatment.

Management of treatment-naïve diabetic macular edema patients: Review of real-world clinical data

The high prevalence of Diabetic macular edema (DME) is a real global health problem. Its complex pathophysiology involves different pathways. Over the last decade, the introduction of intravitreal treatments has dramatically changed the management and prognosis of DME. Among the different treatment options, inhibitors of vascular endothelial growth factor (anti-VEGF) and intravitreal steroids implants represent the first-line therapy of DME. We conducted a review of electronic databases to compile the available evidence about the clinical management of DME in a clinical setting, with a special focus on treatment-naïve patients. Anti-VEGF therapies represent a valuable option for treating DME patients. However, many patients do not respond properly to this treatment and, due to its administration regimen, many patients receive suboptimal treatment in real life. Current evidence demonstrated that in patients with DME, DEX-i improved significantly both anatomic and visual outcomes. Besides eyes with insufficient anti-VEGF respond or recalcitrant DME cases, DEX-i can be effectively and safely used in treatment-naïve DME patients as first line therapy. DEX-i may be considered first line therapy in different clinical scenarios, such as DME eyes with a greater inflammatory component, patients with cardiovascular events, vitrectomized eyes, or those requiring cataract surgery. In conclusion, there are still many points for improvement pending in the clinical management of the patient with DME. Since DME treatment must follow a patient-tailored approach, selecting the best therapeutic approach for each patient requires a good understanding of the pathophysiology of DME.

One-year results of treat-and-extend regimen with intravitreal faricimab for treatment-naïve neovascular age-related macular degeneration

PURPOSE

To evaluate 1-year outcomes of loading phase treatment followed by maintenance therapy using a treat-and-extend (TAE) regimen with intravitreal faricimab for neovascular age-related macular degeneration (nAMD).

STUDY DESIGN

Retrospective, interventional case series.

METHODS

We retrospectively studied 40 eyes of 38 consecutive patients with treatment-naïve nAMD, assessing best-corrected visual acuity (BCVA), foveal thickness, central choroidal thickness (CCT), total number of injections over 1 year, and intended injection interval at the last visit.

RESULTS

Thirty eyes (75.0%) had completed the 1-year intravitreal faricimab treatment. Their BCVA showed significant improvement, with significant reductions in foveal thickness and CCT. The total number of injections during the 1-year treatment period was 6.6 ± 0.7. The intended injection interval at the last visit was 12.7 ± 3.3 weeks. Of the 10 eyes (25.0%) failing to complete the 1-year faricimab treatment, 1 eye developed intraocular inflammation after the loading phase treatment but showed no recurrence of exudative changes, and no further treatment was required. Moreover, 5 eyes switched to intravitreal brolucizumab injection due to persistent exudative changes with an 8-week interval of faricimab injections. The remaining 4 eyes either dropped out or the patient died.

CONCLUSIONS

A loading phase treatment followed by a TAE regimen with intravitreal faricimab appears to be generally safe and effective for improving visual acuity and ameliorating exudative changes in eyes with nAMD. However, there might be cases in which exudative changes cannot be adequately controlled with injections of faricimab every 8 weeks in the maintenance phase.

Thrombospondin-1, BIM and CFH polymorphisms and response to anti-VEGF treatment in neovascular age- related macular degeneration patients

Age-related macular degeneration (AMD) is a vision threatening disease in older adults. Anti-VEGF treatment is effective for the majority of neovascular AMD (nAMD) patients, although approximately 30% of nAMD patients have an incomplete response for unknown reasons. Here we assessed the contribution of single nucleotide polymorphisms (SNPs) in key angioinflammatory regulatory genes in nAMD patients with an incomplete response compared to those responsive to anti-VEGF treatment. A total of 25 responsive and 30 nAMD patients with an incomplete response to anti-vascular endothelial growth factor (anti-VEGF) treatment were examined for known SNPs that impact the structure and function of thromobospondin-1 (TSP1), Bcl-2-interacting mediator of cell death (BIM) and complement factor H (CFH). Plasma levels of C-C motif chemokine ligand 2 (CCL2/MCP1), TSP1 and VEGF were assessed by ELISA. Patients responsive to anti-VEGF treatment showed a significant increase in the TSP1 rs2228262 AA allele and a trend for the BIM (rs724710) CT allele. Consistent with previous reports, 42% of the patients responsive to anti-VEGF expressed the CC allele for CFH rs1061170. Although the CFH TT allele had similarly low prevalence in both groups, the TC allele tended to be more prevalent in patients with an incomplete response. Patients with an incomplete response also had increased plasma CCL2/MCP1 levels, consistent with the role increased inflammation has in the pathogenesis of nAMD. Our studies point to new tools to assess the potential responsiveness of nAMD patients to anti-VEGF treatment and suggest the potential use of anti-CCL2 for treatment of nAMD patients with an incomplete response to anti-VEGF.

Ranibizumab Biosimilars in Treating Retinal Disorders: A Cost-Effective Revolution?

Ranibizumab, is a humanized, monoclonal antibody fragment that binds and inactivates vascular endothelial growth factor-A (VEGF-A) and VEGF-B. One of the main indications for an intravitreal treatment with ranibizumab is age-related macular degeneration (AMD), which is a retinal disease with a high worldwide socioeconomic impact. Biosimilars constitute biological products that demonstrate similar pharmacodynamic and pharmacokinetic characteristics with a reference product, as well as comparable clinical efficacy, safety and immunogenicity. Since the approval of the first biosimilar Razumab, there has been a variety of new biosimilars available on the market. They offer the advantage of the same good clinical and safety results at a better price. All Ranibizumab biosimilars that have gained approval were tested in double masked Phase 3 clinical studies. The use of Ranibizumab biosimilars in neovascular AMD is well reported in the bibliography. Nevertheless, over the last few years, there is a tendency of using biosimilars in other retinal diseases like retinopathy of prematurity (ROP), diabetic macular edema (DME) or polypoidal choroidal vasculopathy (PCV). In conclusion, ranibizumab biosimilars offer a promising avenue for the management of retinal diseases, especially in countries with lower socioeconomic status, where there is lack of availability of innovator ranibizumab. However, further research is required to fully explore their efficacy, safety, and long-term outcomes in a plethora of retinal diseases.

Comparison of antiangiogenic agents (ranibizumab, aflibercept, bevacizumab and ziv-aflibercept) in the therapeutic response to the exudative form of age-related macular degeneration according to the treat-and-extend protocol- true head-to-head study

PURPOSE

To evaluate the structural and functional changes in eyes with neovascular age related macular degeneration (nAMD) in a real-world setting, using Treat and Extend protocol (T&E), comparing four antiangiogenic agents.

METHODS

Prospective, observational, case series study performed in 131 patients with the exudative form of nAMD. Patients were randomly assigned into four groups according to the antiangiogenic agent. During the first year, all eyes received at least 3 monthly intravitreal injections of antiangiogenic agents, and afterwards, were submitted to the T&E.

RESULTS

There was statistically significant difference (p < 0.05) between pre- and post-treatment in the best corrected visual acuity measurements by drug used. Patients who used aflibercept had significantly fewer injections than patients using the other drugs (mean = 9.03). No significant difference was observed between the drugs bevacizumab, ranibizumab and ziv-aflibercept. With regard to biomarkers, patients who used aflibercept and had lower baseline central retinal thickness, absence of hyperreflective foci and no subretinal hyperreflective material had the lowest number of injections.

CONCLUSION

Results indicate that over 2 years, Intravitreal aflibercept on T&E provided better visual and anatomical improvements when compared to other drugs used in this study with significantly fewer injections.

Impact of Nintedanib and Anti-Angiogenic Agents on Uveal Melanoma Cell Behavior

Purpose

The purpose of this study was to investigate the direct impact of the combined angiokinase inhibitor nintedanib as well as the anti-angiogenic agents ranibizumab, bevacizumab, and aflibercept on the primary uveal melanoma (UM) cell line Mel270 and liver metastasis UM cell line OMM2.5.

Methods

The metabolic activity, viability, and oxidative stress levels were analyzed by the Thiazolyl Blue Tetrazolium Bromide (MTT), LIVE/DEAD, and reactive oxygen species (ROS) assays. Expression of intracellular VEGF-A165 and VEGF receptor-2 was detected by immunofluorescent staining. The secretion of VEGF-A165 into the cell culture supernatants was evaluated by VEGF-A165 ELISA.

Results

Nintedanib, at a concentration of 1 µg/mL, resulted in a median reduction of metabolic activity (for Mel270 of approximately 38% and for OMM2.5 of 46% compared to the untreated control) without exerting toxicity in either cell line, whereas the other 3 substances did not result in any changes (which also means that none of the 4 substances led to an increased cell death). Moreover, nintedanib (1 µg/mL) induced oxidative stress in the Mel270 by approximately 1.2 to 1.5-fold compared to the untreated control, but not the OMM2.5 cells.

Conclusions

Nintedanib could suppress the growth of UM cells in a concentration-dependent manner. The metastatic UM cell line OMM2.5 was not sensitive to the pro-oxidant activity of nintedanib. This study was the first to investigate nintedanib in the context of UM. We propose further investigation of this substance to elucidate its effects on this tumor entity with the hope of identifying advantageous therapeutic options for future adjuvant tumor therapies.

Recent advances of anti-angiogenic inhibitors targeting VEGF/VEGFR axis

Vascular endothelial growth factors (VEGF), Vascular endothelial growth factor receptors (VEGFR) and their downstream signaling pathways are promising targets in anti-angiogenic therapy. They constitute a crucial system to regulate physiological and pathological angiogenesis. In the last 20 years, many anti-angiogenic drugs have been developed based on VEGF/VEGFR system to treat diverse cancers and retinopathies, and new drugs with improved properties continue to emerge at a fast rate. They consist of different molecular structures and characteristics, which enable them to inhibit the interaction of VEGF/VEGFR, to inhibit the activity of VEGFR tyrosine kinase (TK), or to inhibit VEGFR downstream signaling. In this paper, we reviewed the development of marketed anti-angiogenic drugs involved in the VEGF/VEGFR axis, as well as some important drug candidates in clinical trials. We discuss their mode of action, their clinical benefits, and the current challenges that will need to be addressed by the next-generation of anti-angiogenic drugs. We focus on the molecular structures and characteristics of each drug, including those approved only in China.

Six-month outcomes of switching from aflibercept to faricimab in refractory cases of neovascular age-related macular degeneration

PURPOSE

To assess 6-month outcomes of switching from aflibercept to faricimab in eyes with refractory neovascular age-related macular degeneration (nAMD) previously requiring monthly injections.

METHODS

This multicenter retrospective study examined nAMD eyes receiving monthly aflibercept injections switched to faricimab administered monthly up to 4 injections followed by injections at a minimum of 2-month intervals as per drug labeling. Data regarding age, sex, number of previous injections, treatment intervals, and best-corrected visual acuity (BCVA) were collected. Central retinal thickness (CRT), subfoveal choroidal thickness (SFCT), and maximal pigment epithelial detachment (PED) height were measured by optical coherence tomography.

RESULTS

The study included 130 eyes of 124 patients. At 6 months, 53 eyes (40.8%) continued on faricimab treatment (Group 1), while 77 eyes (59.2%) discontinued faricimab for various reasons (Group 2) the most common being worse exudation. There were no significant differences between the two groups at baseline. In Group 1, CRT and SFCT significantly decreased at 1 month (P = 0.013 and 0.008), although statistical significance was lost at 6 months (P = 0.689 and 0.052). BCVA and maximal PED height showed no significant changes; however, mean treatment intervals were extended from 4.4 ± 0.5 weeks at baseline to 8.7 ± 1.7 weeks at 6 months (P < 0.001) in Group 1. No clear predictors of response were identified.

CONCLUSION

Switching from aflibercept to faricimab allowed for extension of treatment intervals from monthly to bimonthly in roughly 40% of eyes, suggesting that faricimab may be considered in refractory nAMD cases.

Population Pharmacokinetics of Ranibizumab Delivered via the Port Delivery System Implanted in the Eye in Patients with Neovascular Age-Related Macular Degeneration

The port delivery system with ranibizumab (PDS) is designed to continuously deliver ranibizumab to maintain therapeutic drug concentrations in the vitreous of the eye for an extended duration. The PDS has been evaluated for the treatment of neovascular age-related macular degeneration in the Ladder (PDS 10, 40, and 100 mg/mL, with refill exchanges as needed, versus monthly intravitreal ranibizumab 0.5 mg), Archway (PDS 100 mg/mL with 24-week refill exchanges, versus monthly intravitreal ranibizumab 0.5 mg), and ongoing Portal (PDS 100 mg/mL with 24-week refill exchanges) clinical trials. Data from Ladder, Archway, and Portal were used to develop a population pharmacokinetics (PK) model to estimate the ranibizumab release rate from the PDS implant, describe ranibizumab PK in serum and aqueous humor, and predict the concentration in vitreous humor. A model was developed to adequately describe the serum and aqueous humor PK data, as suggested by goodness-of-fit plots as well as visual predictive checks. In the final model, the first-order implant release rate was estimated to be 0.00654 (1/day), corresponding to a half-life of 106 days, consistent with the implant release rate determined in vitro. The model-predicted vitreous concentrations achieved with PDS 100 mg/mL given every 24 weeks were below the intravitreal peak concentration and above the intravitreal trough concentration of ranibizumab over the entire 24-week refill interval. The results demonstrate a durable release of ranibizumab from the PDS with a half-life of 106 days, providing vitreous exposure to ranibizumab for at least 24 weeks that is within the range of exposure for monthly intravitreal treatment.

From randomised controlled trials to real-world data: Clinical evidence to guide management of diabetic macular oedema

Randomised clinical trials (RCTs) are generally considered the gold-standard for providing scientific evidence for treatments' effectiveness and safety but their findings may not always be generalisable to the broader population treated in routine clinical practice. RCTs include highly selected patient populations that fit specific inclusion and exclusion criteria. Although they may have a lower level of certainty than RCTs on the evidence hierarchy, real-world data (RWD), such as observational studies, registries and databases, provide real-world evidence (RWE) that can complement RCTs. For example, RWE may help satisfy requirements for a new indication of an already approved drug and help us better understand long-term treatment effectiveness, safety and patterns of use in clinical practice. Many countries have set up registries, observational studies and databases containing information on patients with retinal diseases, such as diabetic macular oedema (DMO). These DMO RWD have produced significant clinical evidence in the past decade that has changed the management of DMO. RWD and medico-administrative databases are a useful resource to identify low frequency safety signals. They often have long-term follow-up with a large number of patients and minimal exclusion criteria. We will discuss improvements in healthcare information exchange technologies, such as blockchain technology and FHIR (Fast Healthcare Interoperability Resources), which will connect and extend databases already available. These registries can be linked with existing or emerging retinal imaging modalities using artificial intelligence to aid diagnosis, treatment decisions and provide prognostic information. The results of RCTs and RWE are combined to provide evidence-based guidelines.

Endpoints for clinical trials in ophthalmology

With the identification of novel targets, the number of interventional clinical trials in ophthalmology has increased. Visual acuity has for a long time been considered the gold standard endpoint for clinical trials, but in the recent years it became evident that other endpoints are required for many indications including geographic atrophy and inherited retinal disease. In glaucoma the currently available drugs were approved based on their IOP lowering capacity. Some recent findings do, however, indicate that at the same level of IOP reduction, not all drugs have the same effect on visual field progression. For neuroprotection trials in glaucoma, novel surrogate endpoints are required, which may either include functional or structural parameters or a combination of both. A number of potential surrogate endpoints for ophthalmology clinical trials have been identified, but their validation is complicated and requires solid scientific evidence. In this article we summarize candidates for clinical endpoints in ophthalmology with a focus on retinal disease and glaucoma. Functional and structural biomarkers, as well as quality of life measures are discussed, and their potential to serve as endpoints in pivotal trials is critically evaluated.

Biology and therapeutic targeting of vascular endothelial growth factor A

The formation of new blood vessels, called angiogenesis, is an essential pathophysiological process in which several families of regulators have been implicated. Among these, vascular endothelial growth factor A (VEGFA; also known as VEGF) and its two tyrosine kinase receptors, VEGFR1 and VEGFR2, represent a key signalling pathway mediating physiological angiogenesis and are also major therapeutic targets. VEGFA is a member of the gene family that includes VEGFB, VEGFC, VEGFD and placental growth factor (PLGF). Three decades after its initial isolation and cloning, VEGFA is arguably the most extensively investigated signalling system in angiogenesis. Although many mediators of angiogenesis have been identified, including members of the FGF family, angiopoietins, TGFβ and sphingosine 1-phosphate, all current FDA-approved anti-angiogenic drugs target the VEGF pathway. Anti-VEGF agents are widely used in oncology and, in combination with chemotherapy or immunotherapy, are now the standard of care in multiple malignancies. Anti-VEGF drugs have also revolutionized the treatment of neovascular eye disorders such as age-related macular degeneration and ischaemic retinal disorders. In this Review, we emphasize the molecular, structural and cellular basis of VEGFA action as well as recent findings illustrating unexpected interactions with other pathways and provocative reports on the role of VEGFA in regenerative medicine. We also discuss clinical and translational aspects of VEGFA. Given the crucial role that VEGFA plays in regulating angiogenesis in health and disease, this molecule is largely the focus of this Review.

Short-term outcomes of intravitreal faricimab for treatment-naïve neovascular age-related macular degeneration

PURPOSE

To investigate the efficacy and safety of loading phase treatment with 3 monthly intravitreal injections of faricimab for neovascular age-related macular degeneration (nAMD).

METHODS

We retrospectively analyzed 16-week outcomes of 40 consecutive eyes of 38 patients with treatment-naïve nAMD. Three monthly injections of faricimab were administered to all eyes as a loading phase treatment. Best-corrected visual acuity (BCVA), foveal thickness, central choroidal thickness (CCT), and dry macula achievement were all assessed every 4 weeks. Moreover, the regression of polypoidal lesions was evaluated after the loading phase.

RESULTS

BCVA was 0.33 ± 0.41 at baseline and showed significant improvement to 0.22 ± 0.36 at week 16 (P < 0.01). Foveal thickness was 278 ± 116 µm at baseline, decreasing significantly to 173 ± 48 µm at week 16 (P < 0.01). CCT was 214 ± 98 µm at baseline, decreasing significantly to 192 ± 89 µm at week 16 (P < 0.01). Dry macula was achieved in 31 eyes (79.5%) at week 16. Indocyanine green angiography after the loading phase revealed complete regression of polypoidal lesions in 11 of 18 eyes (61.1%) with polypoidal lesions. One eye (2.5%) developed vitritis without visual loss at week 16.

CONCLUSION

Loading phase treatment with intravitreal faricimab appears to generally be safe and effective for improving visual acuity and reducing exudative changes in eyes with nAMD.

Intravitreal Therapy for Uveitic Macular Edema-Ranibizumab versus Methotrexate versus the Dexamethasone Implant: The MERIT Trial Results

PURPOSE

To evaluate the effectiveness of 3 different intravitreal treatments for persistent or recurrent uveitic macular edema (ME): dexamethasone implant, methotrexate, and ranibizumab.

DESIGN

Single-masked, randomized controlled clinical trial.

PARTICIPANTS

Patients with minimally active or inactive uveitis and persistent or recurrent uveitic ME in one or both eyes.

METHODS

Patients at 33 centers were randomized 1:1:1 to receive 1 of the 3 therapies. Patients with bilateral ME received the same treatment in both eyes.

MAIN OUTCOME MEASURES

The primary outcome, measured at 12 weeks, was reduction in central subfield thickness (CST) expressed as a proportion of baseline (CST per CST at baseline) assessed with spectral-domain OCT by readers masked to treatment assignment. Secondary outcomes included improvement and resolution of ME, change in best-corrected visual acuity (BCVA), and elevations in intraocular pressure (IOP).

RESULTS

One hundred ninety-four participants (225 eligible eyes) were randomized to dexamethasone (n = 65 participants and 77 eyes), methotrexate (n = 65 participants and 79 eyes), or ranibizumab (n = 64 participants and 69 eyes). All received at least 1 injection of the assigned treatment. At the 12-week primary outcome point, each group showed significant reductions in CST relative to baseline: 35%, 11%, and 22% for dexamethasone, methotrexate, and ranibizumab, respectively. Reduction of ME was significantly greater in the dexamethasone group than for either methotrexate (P < 0.01) or ranibizumab (P = 0.018). Only the dexamethasone group showed a statistically significant improvement in BCVA during follow-up (4.86 letters; P < 0.001). Elevations of IOP by 10 mmHg, to 24 mmHg or more, or both were more common in the dexamethasone group; IOP spikes to 30 mmHg or more were uncommon overall and were not significantly different among groups. Reductions in BCVA of 15 letters or more were more common in the methotrexate group and typically were attributable to persistent ME.

CONCLUSIONS

At 12 weeks, in eyes with minimally active or inactive uveitis, dexamethasone was significantly better at treating persistent or recurrent ME than methotrexate or ranibizumab. Risk of IOP elevation was greater with dexamethasone, but elevations to levels of 30 mmHg or more were infrequent.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Revisiting Retinal Degeneration Hallmarks: Insights from Molecular Markers and Therapy Perspectives

Visual impairment and blindness are a growing public health problem as they reduce the life quality of millions of people. The management and treatment of these diseases represent scientific and therapeutic challenges because different cellular and molecular actors involved in the pathophysiology are still being identified. Visual system components, particularly retinal cells, are extremely sensitive to genetic or metabolic alterations, and immune responses activated by local insults contribute to biological events, culminating in vision loss and irreversible blindness. Several ocular diseases are linked to retinal cell loss, and some of them, such as retinitis pigmentosa, age-related macular degeneration, glaucoma, and diabetic retinopathy, are characterized by pathophysiological hallmarks that represent possibilities to study and develop novel treatments for retinal cell degeneration. Here, we present a compilation of revisited information on retinal degeneration, including pathophysiological and molecular features and biochemical hallmarks, and possible research directions for novel treatments to assist as a guide for innovative research. The knowledge expansion upon the mechanistic bases of the pathobiology of eye diseases, including information on complex interactions of genetic predisposition, chronic inflammation, and environmental and aging-related factors, will prompt the identification of new therapeutic strategies.

The evolving therapeutic landscape of diabetic retinopathy

INTRODUCTION

Diabetic retinopathy (DR) is a leading cause of blindness worldwide. Recent decades have seen rapid progress in the management of diabetic eye disease, evolving from pituitary ablation to photocoagulation and intravitreal pharmacotherapy. The advent of effective intravitreal drugs inhibiting vascular endothelial growth factor (VEGF) marked a new era in DR therapy. Sustained innovation has since produced several promising biologics targeting angiogenesis, inflammation, oxidative stress, and neurodegeneration.

AREAS COVERED

This review surveys traditional, contemporary, and emerging therapeutics for DR, with an emphasis on anti-VEGF therapies, receptor tyrosine kinase inhibitors, angiopoietin-Tie2 pathway inhibitors, integrin pathway inhibitors, gene therapy 'biofactory' approaches, and novel systemic therapies. Some of these investigational therapies are being delivered intravitreally via sustained release technologies for extended durability. Other investigational agents are being delivered non-invasively via topical and systemic routes. These strategies hold promise for early and long-lasting treatment of DR.

EXPERT OPINION

The evolving therapeutic landscape of DR is rapidly expanding our toolkit for the effective and durable treatment of blinding eye disease. However, further research is required to validate the efficacy of novel therapeutics and characterize real world outcomes.

High‑dose aflibercept injection has striking effects on myopic choroidal neovascularization

The aim of the present study was to evaluate the 1-year outcomes of a high-dose aflibercept injection [4 mg 2+ pro re nata (PRN) scheme] for individuals with myopic choroidal neovascularization (mCNV) through optical coherence tomography (OCT) follow-ups. A total of 16 consecutive patients (7 males and 9 females; sixteen eyes) with mCNV were enrolled in this retrospective study. The mean age was 30.5±3.35 years and mean spherical equivalent was -7.31±0.90 D. Subjects received 4 mg aflibercept intravitreal injection on the day of diagnosis and 35 days later. Further injections of aflibercept were required when the following were detected by OCT and fluorescein angiography: i) Decrease in best corrected visual acuity (BCVA); ii) aggravation of metamorphopsia; iii) macular oedema; iv) macular haemorrhage; v) increase in retinal thickness; and vi) leakage. Ophthalmic examination and OCT were performed at the baseline, as well as at 1, 2, 4, 6, 8, 10 and 12 months after the initial aflibercept injection. BCVA and central retinal thickness (CRT) were evaluated at each follow-up. The results showed that the vision of all subjects improved following the aflibercept intravitreal injection. The mean BCVA improved from 0.35±0.15 logarithm of the minimal angle of resolution (logMAR) at the baseline to 0.12±0.05 logMAR at final follow-up (P<0.05). A reduction in metamorphopsia was observed and the mean CRT was reduced from 345.38±34.69 µm of pre-treatment levels to 222.75±8.98 µm at the last postoperative visit (P<0.05). The mean number of injections in the present study was 2.13±0.5. Out of all patients, 13 received two injections and 3 subjects received three injections. The mean follow-up was 13.41±1.17 months. Based on the outcomes, it was found that an intravitreal injection of high-dose aflibercept (4 mg 2+PRN scheme) is effective for vision improvement and stabilization. In addition, it also significantly alleviated metamorphopsia and reduced the CRT in patients treated with mCNV. During the follow-up, the eyesight of the patients was stable.

Targeting angiogenesis in oncology, ophthalmology and beyond

Angiogenesis is an essential process in normal development and in adult physiology, but can be disrupted in numerous diseases. The concept of targeting angiogenesis for treating diseases was proposed more than 50 years ago, and the first two drugs targeting vascular endothelial growth factor (VEGF), bevacizumab and pegaptanib, were approved in 2004 for the treatment of cancer and neovascular ophthalmic diseases, respectively. Since then, nearly 20 years of clinical experience with anti-angiogenic drugs (AADs) have demonstrated the importance of this therapeutic modality for these disorders. However, there is a need to improve clinical outcomes by enhancing therapeutic efficacy, overcoming drug resistance, defining surrogate markers, combining with other drugs and developing the next generation of therapeutics. In this Review, we examine emerging new targets, the development of new drugs and challenging issues such as the mode of action of AADs and elucidating mechanisms underlying clinical benefits; we also discuss possible future directions of the field.

Systematic review of efficacy and meta-analysis of safety of ranibizumab biosimilars relative to reference ranibizumab anti-VEGF therapy for nAMD treatment

TOPIC

This systematic review and meta-analysis provides a summary of the efficacy and safety of ranibizumab biosimilars relative to reference ranibizumab anti-vascular endothelial growth factor (VEGF) therapy for the treatment of neovascular age-related macular degeneration (nAMD).

METHODS

We conducted systematic searches from January 2003 to August 2022 on Ovid MEDLINE, EMBASE and the Cochrane Controlled Register of Trials. We included studies reporting changes in early treatment diabetic retinopathy study-measured best-corrected visual acuity (BCVA), number of patients who lost or gained more than 15 letters in BCVA from baseline, changes in retinal thickness and adverse events between treatment arms. The following studies were excluded: studies that did not report visual outcomes following biosimilar and reference ranibizumab intravitreal injections, study arms combining anti-VEGF agents with laser or steroid injections, sham injections as a control comparator, studies without English full texts and non-comparative, observational study design.

RESULTS

Five studies reported on four randomised controlled trials (RCTs) and 1544 eyes at baseline were included in this systematic review and meta-analysis. The studies in our systematic review found no significant differences between reference ranibizumab and ranibizumab biosimilar medications (FYB201, SB11, RanizuRel and Lupin's ranibizumab) for visual and anatomical outcomes. No significant differences were detected between biosimilar and reference ranibizumab for treatment emergent adverse events (risk ratio, RR 1.06, 95% CI (0.91 to 1.23), p=0.45, I²=52%) or IOP-related adverse events with significant heterogeneity (RR 2.59, 95% CI (0.11 to 62.25), p=0.56, I²=76%).

CONCLUSION

This systematic review of four RCTs demonstrated no significant difference in visual outcomes, retinal thickness outcomes, as well as meta-analysis of adverse events between biosimilar and reference ranibizumab therapies for nAMD treatment.

Current Treatments for Diabetic Macular Edema

Diabetic retinopathy is a major retinal disorder and a leading cause of blindness. Diabetic macular edema (DME) is an ocular complication in patients with diabetes, and it can impair vision significantly. DME is a disorder of the neurovascular system, and it causes obstructions of the retinal capillaries, damage of the blood vessels, and hyperpermeability due to the expression and action of vascular endothelial growth factor (VEGF). These changes result in hemorrhages and leakages of the serous components of blood that result in failures of the neurovascular units (NVUs). Persistent edema of the retina around the macula causes damage to the neural cells that constitute the NVUs resulting in diabetic neuropathy of the retina and a reduction in vision quality. The macular edema and NVU disorders can be monitored by optical coherence tomography (OCT). Neuronal cell death and axonal degeneration are irreversible, and their development can result in permanent visual loss. Treating the edema before these changes are detected in the OCT images is necessary for neuroprotection and maintenance of good vision. This review describes the effective treatments for the macular edema that are therefore neuroprotective.

Rethinking the potential and necessity of drug delivery systems in neovascular age-related macular degeneration therapy

Age-related macular degeneration (AMD) is the predominant threat to human vision and ultimately results in blindness. With the increase in the aging population, it has become a more crucial issue to human health. AMD is a multifactorial disease with the unique feature of uncontrollable angiogenesis during initiation and progression. Although increasing evidence indicates that AMD is largely hereditary, the predominant efficient treatment is antiangiogenesis, which mainly involves VEGF and HIF-α as therapeutic targets. The repeated administration of this treatment over the long term, generally through intravitreal injection, has called for the introduction of long-term drug delivery systems, which are expected to be achieved by biomaterials. However, the clinical results of the port delivery system indicate that the optimization of medical devices toward prolonging the activities of therapeutic biologics in AMD therapy seems more promising. These results indicate that we should rethink the possibility and potential of biomaterials as drug delivery systems in achieving long-term, sustained inhibition of angiogenesis in AMD therapy. In this review, the etiology, categorization, risk factors, pathogenesis, and current clinical treatments of AMD are briefly introduced. Next, the development status of long-term drug delivery systems is discussed, and the drawbacks and shortages of these systems are emphasized. By comprehensively considering the pathological aspect and the recent application of drug delivery systems in AMD therapy, we hope to find a better solution for the further development of long-term therapeutic strategies for AMD.

Topical bromfenac as adjunctive treatment with intravitreal ranibizumab for diabetic macular edema

PURPOSE

To determine the safety and efficacy of adding topical bromfenac 0.09% in the treatment of diabetic macular edema.

METHODS

Seventy patients (70 eyes) with center involved diabetic macular edema with macular thickness (300-500 μm) were included. Patients were divided randomly into two groups: 35 eyes in each group. Both groups were treated with intravitreal ranibizumab monthly for three consecutive months. Bromfenac 0.09% eye drops twice daily was added to the treatment of study group for six months from commencement of treatment. The efficacy of topical bromfenac was evaluated by comparing both groups through follow-up period as regards to visual acuity, central and average thickness and the need for re-injection.

RESULTS

Patients treated with topical bromfenac in addition to intravitreal ranibizumab revealed significant improvement in visual acuity, more reduction in central and average macular thickness and less tendency to need reinjection compared to those treated with ranibizumab alone (p 0.013, p 0.010 and p 0.022, respectively). No side effects was encountered with the use of topical bromfenac.

CONCLUSION

Topical bromfenac 0.09% twice a day could enhance and sustain the efficacy of intravitreal ranibizumab in the treatment of diabetic macular edema without increasing the incidence of corneal side effects.

Anti-Angiogenic Activity of Drugs in Multiple Myeloma

Angiogenesis represents a pivotal hallmark of multiple myeloma (MM) that correlates to patients’ prognosis, overall survival, and drug resistance. Hence, several anti-angiogenic drugs that directly target angiogenic cytokines (i.e., monoclonal antibodies, recombinant molecules) or their cognate receptors (i.e., tyrosine kinase inhibitors) have been developed. Additionally, many standard antimyeloma drugs currently used in clinical practice (i.e., immunomodulatory drugs, bisphosphonates, proteasome inhibitors, alkylating agents, glucocorticoids) show anti-angiogenic effects further supporting the importance of inhibiting angiogenesis from potentiating the antimyeloma activity. Here, we review the most important anti-angiogenic therapies used for the management of MM patients with a particular focus on their pharmacological profile and on their anti-angiogenic effect in vitro and in vivo. Despite the promising perspective, the direct targeting of angiogenic cytokines/receptors did not show a great efficacy in MM patients, suggesting the need to a deeper knowledge of the BM angiogenic niche for the design of novel multi-targeting anti-angiogenic therapies.

Role of Oxidative Stress in Ocular Diseases: A Balancing Act

Redox homeostasis is a delicate balancing act of maintaining appropriate levels of antioxidant defense mechanisms and reactive oxidizing oxygen and nitrogen species. Any disruption of this balance leads to oxidative stress, which is a key pathogenic factor in several ocular diseases. In this review, we present the current evidence for oxidative stress and mitochondrial dysfunction in conditions affecting both the anterior segment (e.g., dry eye disease, keratoconus, cataract) and posterior segment (age-related macular degeneration, proliferative vitreoretinopathy, diabetic retinopathy, glaucoma) of the human eye. We posit that further development of therapeutic interventions to promote pro-regenerative responses and maintenance of the redox balance may delay or prevent the progression of these major ocular pathologies. Continued efforts in this field will not only yield a better understanding of the molecular mechanisms underlying the pathogenesis of ocular diseases but also enable the identification of novel druggable redox targets and antioxidant therapies.

Polypoidal Choroidal Vasculopathy: An Update on Diagnosis and Treatment

Polypoidal choroidal vasculopathy (PCV) is a vascular disease of the choroid that leads to hemorrhagic and exudative macular degeneration. It may cause significant vision loss and thus affect the quality-of-life and psychological well-being. Non-invasive, non-ICGA-based OCT criteria have shown reliable results to plan adjunct photodynamic therapy (PDT) treatment, with the complete and consistent coverage of polypoidal lesions (PL) and branching neovascular network (BNN). The safety and efficacy of anti-vascular endothelial growth factor (anti-VEGF) monotherapy and its combination with verteporfin PDT have been established. However, treatment is still challenging due to frequent follow-ups, non-availability of PDT, and need for multiple anti-VEGF injection visits that increase the treatment burden and lead to patients being lost to follow-up. Effective treatments that prolong intervals between injections while maintaining vision and anatomical gains remain a critical unmet need. Longer acting molecules, like brolucizumab, have shown non-inferiority in BCVA gains and superior anatomical outcomes compared to other anti-VEGF agents. Newer therapies in the pipeline to enhance the efficacy and longevity of treatment include Faricimab and a port delivery system (PDS). This review summarizes the most recent diagnostic and treatment approaches in PCV to offer better treatment avenues.

Biosimilar versus InnovAtor MoLecule of RAnibizumab in Neovascular Age-Related MaCular DEgeneration (The BALANCE Trial): Real-World Evidence

Purpose

To analyse outcomes of innovator ranibizumab (IRM) (Lucentis) and biosimilar ranibizumab (BRM) (Razumab) in Indian eyes with neovascular age-related macular degeneration (nAMD).

Methods

Retrospective observational study in nAMD patients, who were treated with IRM or BRM (3 loading doses followed by pro re nata (PRN). Primary outcome measures were change in best corrected visual acuity (BCVA) and central macular thickness (CMT) along with safety analysis. Secondary outcomes measures were changes in the subretinal fluid (SRF) and intraretinal fluid (IRF).

Results

Inclusion criteria were satisfied in 164 eyes (60.74%). A total of 87 eyes were treated with IRM, and 77 eyes received BRM. Baseline BCVA was 0.57±0.27 logMAR in IRM group and 0.61±0.25 in the BRM group. At 3, 6, 9, and 12 months BCVA was 0.27±0.22 (p<0.0001), 0.34±0.23 (p<0.0001), 0.39±0.25 (p<0.0001), and 12 months 0.41±0.23 (p<0.0001) in the IRM group and 0.24±0.16 (p<0.0001), 0.27±0.16 (p<0.0001), 0.34±0.17 (p<0.0001), 0.38±0.18 (p<0.0001) in the BRM group. Baseline CMT was 420.39±54.45 μm in IRM group and 407.82±53.07 μm in BRM group. At 3, 6, 9, and 12 months, CMT decreased to 258.28±20.4 μm (p<0.0001), 268.38±19.5 μm (p<0.0001), 269.51±32.41 μm (p<0.0001), and 278.28±16.56 μm (p<0.0001) in the IRM group and 258.84±17.47 μm (p<0.0001), 265.69±17.29 μm (p<0.0001), 273.64±23.13 μm (p<0.0001), and 283.09±19.66 μm (p<0.0001) in the BRM group. Similar improvements in IRF and SRF levels in the patients were noted in both groups. Required number of doses of IRM and BRM was similar over the 12 month period in both groups. A similar profile of adverse events was noted in both the groups.

Conclusion

Intravitreal injection of IRM and BRM show similar efficacy and safety in Indian eyes with nAMD.

Assessment of mouse VEGF neutralization by ranibizumab and aflibercept

PURPOSE

To assess the interaction between ranibizumab, aflibercept, and mouse vascular endothelial growth factor (VEGF), both in vivo and in vitro.

METHODS

In vivo, the effect of intravitreal injection of ranibizumab and aflibercept on oxygen induced retinopathy (OIR) and the effect of multiple intraperitoneal injections of ranibizumab and aflibercept on neonatal mice were assessed. In vitro, the interaction of mouse VEGF-A with aflibercept or ranibizumab as the primary antibody was analyzed by Western blot.

RESULTS

In both experiments using intravitreal injections in OIR mice and multiple intraperitoneal injections in neonatal mice, anti-VEGF effects were observed with aflibercept, but not with ranibizumab. Western blot analysis showed immunoreactive bands for mouse VEGF-A in the aflibercept-probed blot, but not in the ranibizumab-probed blot.

CONCLUSIONS

Aflibercept but not ranibizumab interacts with mouse VEGF, both in vivo and in vitro. When conducting experiments using anti-VEGF drugs in mice, aflibercept is suitable, but ranibizumab is not.

RNAapt3D: RNA aptamer 3D-structural modeling database

RNA aptamers are oligonucleotides with high binding affinity and specificity for target molecules and are expected to be a new generation of therapeutic molecules and targeted delivery materials. The tertiary structure of RNA molecules and RNA-protein interaction sites are increasingly important as potential targets for new drugs. The pathological mechanisms of diseases must be understood in detail to guide drug design. In developing RNA aptamers as drugs, information about the interaction mechanisms and structures of RNA aptamer-target protein complexes are useful. We constructed a database, RNA aptamer 3D-structural modeling (RNAapt3D), consisting of RNA aptamer data that are potential drug candidates. The database includes RNA sequences and computationally predicted RNA tertiary structures based on secondary structures and implements methods that can be used to predict unknown structures of RNA aptamer-target molecule complexes. RNAapt3D should enable the design of RNA aptamers for target molecules and improve the efficiency and productivity of candidate drug selection. RNAapt3D can be accessed at https://rnaapt3d.medals.jp.

A Review of Neovascular Glaucoma: Etiology, Pathogenesis, Diagnosis, and Treatment

Neovascular glaucoma (NVG) is a rare, aggressive, blinding secondary glaucoma, which is characterized by neovascularization of the anterior segment of the eye and leading to elevation of the intraocular pressure (IOP). The main etiological factor is retinal ischemia leading to an impaired homeostatic balance between the angiogenic and antiangiogenic factors. High concentrations of vasogenic substances such as vascular endothelial growth factor (VEGF) induce neovascularization of the iris (NVI) and neovascularization of the angle (NVA) that limits the outflow of aqueous humor from the anterior chamber and increases the IOP. NVG clinical, if untreated, progresses from secondary open-angle glaucoma to angle-closure glaucoma, leading to irreversible blindness. It is an urgent ophthalmic condition; early diagnosis and treatment are necessary to preserve vision and prevent eye loss. The management of NVG requires the cooperation of retinal and glaucoma specialists. The treatment of NVG includes both control of the underlying disease and management of IOP. The main goal is the prevention of angle-closure glaucoma by combining panretinal photocoagulation (PRP) and antiangiogenic therapy. The aim of this review is to summarize the current available knowledge about the etiology, pathogenesis, and symptoms of NVG and determine the most effective treatment methods.

Resveratrol: Its Path from Isolation to Therapeutic Action in Eye Diseases

Due to the confirmed therapeutic potential of resveratrol (Rv) for eye diseases, namely its powerful anti-angiogenic and antioxidant effects, this molecule must be studied more deeply. Nowadays, the pharmaceutic and pharmacokinetic available studies offer a troubling picture because of its low stability and bioavailability. To overcome this problem, researchers started to design and create different delivery systems that could improve the delivery amount of Rv. Therefore, this review aims to shed light on the proper and efficient techniques to isolate, purify and quantify the Rv molecule, and how this therapeutic molecule can be a part of a delivery system. The Rv great impact on aspects regarding its stability, bioavailability and absorption are also debated here, based on the existent literature on in vitro and in vivo human and animal studies. Moreover, after its absorption the Rv influence at the molecular level in ocular pathologies is described. In addition, the present review summarizes the available literature about Rv, hoping that Rv will gain more attention to investigate its unexplored side.

VEGF-targeting drugs for the treatment of retinal neovascularization in diabetic retinopathy

Diabetic retinopathy (DR) is the most common microangiopathic complication of diabetes mellitus, representing a major cause of visual impairment in developed countries. Proliferative DR (PDR) represents the last stage of this extremely complex retinal disease, characterized by the development of neovascularization induced by the abnormal production and release of vascular endothelial growth factor (VEGF). The term VEGF includes different isoforms; VEGF-A represents one of the most important pathogenic factors of DR. Anti-VEGF intravitreal therapies radically changed the outcome of DR, due to combined anti-angiogenic and anti-edematous activities. Nowadays, several anti-VEGF molecules exist, characterized by different pharmacological features and duration. With respect to PDR, although anti-VEGF treatments represented a fundamental step forward in the management of this dramatic complication, a big debate is present in the literature regarding the role of anti-VEGF as substitute of panretinal photocoagulation or if these two approaches may be used in combination. In the present review, we provided an update on VEGF isoforms and their role in DR pathogenesis, on current anti-VEGF molecules and emerging new drugs, and on the current management strategies of PDR. There is an overall agreement regarding the relative advantage provided by anti-VEGF, especially looking at the management of PDR patients requiring vitrectomy, with respect to laser. Based on the current data, laser approaches might be avoided when a perfectly planned anti-VEGF therapeutic strategy can be adopted. Conversely, laser treatment may have a role for those patients unable to guarantee enough compliance to anti-VEGF injections.Key messagesVEGF increased production, stimulated by retinal hypoperfusion and ischaemia, is a major pathogenic factor of neovascular complication onset in diabetic retinopathy and of DR stages progression.Nowadays, several anti-VEGF molecules are available in clinical practice and other molecules are currently under investigation. Each anti-VEGF molecule is characterized by different targets and may interact with multiple biochemical pathways within the eye.All the data agreed in considering anti-VEGF molecules as a first line choice for the management of diabetic retinopathy. Laser treatments may have a role in selected advanced cases and for those patients unable to guarantee enough compliance to intravitreal treatments schemes.

Ocular adverse events associated with anti-VEGF therapy: A pharmacovigilance study of the FDA adverse event reporting system (FAERS)

Background: The purpose of this study is to identify and characterize ocular adverse events (AEs) that are significantly associated with anti-VEGF drugs for treatment of neovascular age-related macular degeneration and compare the differences between each drug, and provide clinical reference. Methods: Ocular AEs submitted to the US Food and Drug Administration were analyzed to map the safety profile of anti-VEGF drugs. The Pharmacovigilance tools used for the quantitative detection of signals were reporting odds ratio and bayesian confidence propagation neural network. Results: A total of 10,608,503 AE reports were retrieved from FAERS, with 20,836 for ranibizumab, 19,107 for aflibercept, and 2,442 for brolucizumab between the reporting period of Q1, 2004 and Q3, 2021. We found and analyzed the different AEs with the strongest signal in each drug-ranibizumab-macular ischaemia (ROR = 205.27, IC-2SD = 3.70), retinal pigment epithelial tear (ROR = 836.54, IC-2SD = 7.19); aflibercept-intraocular pressure increased (ROR = 31.09, IC-2SD = 4.61), endophthalmitis (ROR = 178.27, IC-2SD = 6.70); brolucizumab-retinal vasculitis (ROR = 2930.41, IC-2SD = 7.47) and/or retinal artery occlusion (ROR = 391.11, IC-2SD = 6.10), dry eye (ROR = 12.48, IC-2SD = 2.88). Conclusion: The presence of AEs should bring clinical attention. The use of anti-VEGF drugs should be based on the patient's underlying or present medical condition to reduce any adverse event associated with the treatment.

Current and Novel Therapeutic Approaches for Treatment of Neovascular Age-Related Macular Degeneration

Age-related macular degeneration AMD is one of the leading causes of blindness in the elderly population. An advanced form of AMD known as neovascular AMD (nAMD) is implicated as the main attributor of visual loss among these patients. The hallmark feature of nAMD is the presence of neovascular structures known as choroidal neovascular membranes (CNVs), along with fluid exudation, hemorrhages, and subretinal fibrosis. These pathological changes eventually result in anatomical and visual loss. A type of proangiogenic factor known as vascular endothelial growth factor (VEGF) has been known to mediate the pathological process behind nAMD. Therefore, therapy has transitioned over the years from laser therapy that ablates the lesions to using Anti-VEGF to target the pathology directly. In this work, we provide an overview of current and emerging therapies for the treatment of nAMD. Currently approved Anti-VEGF agents include ranibizumab, aflibercept, and brolucizumab. Bevacizumab, also an Anti-VEGF agent, is used to manage nAMD even though this is an off-label use. While Anti-VEGF agents have provided a favorable prognosis for nAMD, they are associated with a substantial financial burden for patients and the healthcare system, due to their high cost as well as the need for frequent repeat treatments and visits. Emerging therapies and studies aim to extend the intervals between required treatments and introduce new treatment modalities that would improve patients’ compliance and provide superior results.

A Linkage between Angiogenesis and Inflammation in Neovascular Age-Related Macular Degeneration

Age-related macular degeneration (AMD) is the leading cause of visual impairment in the aging population with a limited understanding of its pathogenesis and the number of patients are all the time increasing. AMD is classified into two main forms: dry and neovascular AMD (nAMD). Dry AMD is the most prevalent form (80–90%) of AMD cases. Neovascular AMD (10–20% of AMD cases) is treated with monthly or more sparsely given intravitreal anti-vascular endothelial growth factor inhibitors, but unfortunately, not all patients respond to the current treatments. A clinical hallmark of nAMD is choroidal neovascularization. The progression of AMD is initially characterized by atrophic alterations in the retinal pigment epithelium, as well as the formation of lysosomal lipofuscin and extracellular drusen deposits. Cellular damage caused by chronic oxidative stress, protein aggregation and inflammatory processes may lead to advanced geographic atrophy and/or choroidal neovascularization and fibrosis. Currently, it is not fully known why different AMD phenotypes develop. In this review, we connect angiogenesis and inflammatory regulators in the development of nAMD and discuss therapy challenges and hopes.

Efficacy and safety of intravitreal anti-VEGF therapy in diabetic retinopathy: what we have learned and what should we learn further?

INTRODUCTION

Diabetic retinopathy (DR) is one of the most frequent microvascular complications of diabetes that can lead to blindness. Laser treatment has been the gold standard treatment for diabetic macular edema (DME) and proliferative diabetic retinopathy (PDR) for many years. Recently, the role of vascular endothelial growth factor (VEGF) has been established in the pathogenesis of DR, and the use of intravitreal anti-VEGF therapy has gained popularity for the management of DR.

AREAS COVERED

This review includes a brief overview of the efficacy and safety of currently available (bevacizumab, ranibizumab, and aflibercept) and potential future (brolucizumab, faricimab, and KSI-301) anti-VEGF agents in patients with DR based mainly on publicly available data from phase 1, 2 and 3 clinical trials.

EXPERT OPINION

Clinical trials investigating the efficacy of intravitreal bevacizumab, ranibizumab, and aflibercept injections demonstrated favorable functional and anatomical outcomes in patients with DME. Moreover, the use of these anti-VEGF agents showed a significant improvement in the severity of DR. Recent clinical research for future anti-VEGF molecules aims to provide higher target-protein binding affinity and prolonged therapeutic effect. Brolucizumab, faricimab, and KSI-301 are three novel anti-VEGF agents that demonstrate promising data for the management of DME and potentially DR.

Beovu, but not Lucentis impairs the function of the barrier formed by retinal endothelial cells in vitro

Because rare, but severe adverse effects, i.e. retinal vasculitis or retinal vein occlusion, have been observed after repetitive intravitreal injections of VEGF-A-binding single-chain variable fragment brolucizumab (Beovu), we investigated its possible impact on the barrier formed by immortalized bovine retinal endothelial cells (iBREC) in comparison to that of the VEGF-A-binding Fab fragment ranibizumab (Lucentis). As a measure of stability of the barrier formed by a confluent monolayer of iBREC, we determined the cell index over seven days by continuous electric cell-substrate impedance measurements: Beovu but not Lucentis indeed significantly lowered the cell index, evident about 1.5 days after its addition, pointing to barrier impairment. Early after addition of Beovu, amounts of the integrins α5 and β1-subunits of the fibronectin receptor-had changed in opposite ways, suggesting an effect on cell adhesion due to hindered dimer formation. After exposure for eight days to Beovu, levels of claudin-1-an essential part of the iBREC barrier-were significantly lower, less claudin-1 was located at the plasma membrane after exposure to the VEGF-A antagonist for five days. Beovu did not induce secretion of inflammatory cytokines or VEGF-A. Interestingly, polysorbate-80-component of Beovu-but not polysorbate-20-in Lucentis-slightly, but significantly lowered the cell index, also associated with reduced claudin-1 expression. In summary, our results indicate that Beovu changes the behavior of retinal endothelial cells, thus providing an alternative "non-immunological" explanation for the most relevant of observed side effects.

Pharmacokinetics of the Port Delivery System with Ranibizumab in the Ladder Phase 2 Trial for Neovascular Age-Related Macular Degeneration

INTRODUCTION

Ladder was a phase 2 trial that evaluated the Port Delivery System with ranibizumab (PDS) for neovascular age-related macular degeneration. Serum and aqueous humor samples were collected to characterize the pharmacokinetics (PK) of ranibizumab delivered through the PDS.

METHODS

Ladder was a multicenter, randomized, active treatment-controlled, phase 2 clinical trial. Patients with neovascular age-related macular degeneration (n = 220) were randomized (3:3:3:2) to PDS 10 mg/ml, PDS 40 mg/ml, PDS 100 mg/ml, or monthly intravitreal ranibizumab 0.5 mg. Serum PK samples were collected in all arms and analyzed for ranibizumab concentration using an enzyme-linked immunosorbent assay. The main PK analyses were conducted in the PK-evaluable population (n = 68), which excluded patients who received fellow eye intravitreal treatment, supplemental ranibizumab treatment, or had previous treatment with bevacizumab in either eye within 9 months of randomization.

RESULTS

In the PDS 10 mg/ml arm, median serum ranibizumab concentrations were below the serum trough concentration (C_trough; 130 pg/ml) expected with monthly intravitreal ranibizumab 0.5 mg at all time points. In the PDS 40 mg/ml and 100 mg/ml arms, median serum ranibizumab concentrations were above the C_trough expected with monthly intravitreal ranibizumab 0.5 mg (130 pg/ml) through month 3 and month 12 after implantation, respectively, and remained above the lower limit of quantification through month 15 and month 16 after implantation, respectively.

CONCLUSIONS

These PK data indicate that the implant in the PDS 100 mg/ml arm maintained ranibizumab concentrations within the range of monthly intravitreal ranibizumab 0.5 mg injections (130-2220 pg/ml) through month 12 after implantation.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT02510794.

Antibody-Incorporated Nanomedicines for Cancer Therapy

Antibody-based cancer therapy, one of the most significant therapeutic strategies, has achieved considerable success and progress over the past decades. Nevertheless, obstacles including limited tumor penetration, short circulation half-lives, undesired immunogenicity, and off-target side effects remain to be overcome for the antibody-based cancer treatment. Owing to the rapid development of nanotechnology, antibody-containing nanomedicines that have been extensively explored to overcome these obstacles have already demonstrated enhanced anticancer efficacy and clinical translation potential. This review intends to offer an overview of the advancements of antibody-incorporated nanoparticulate systems in cancer treatment, together with the nontrivial challenges faced by these next-generation nanomedicines. Diverse strategies of antibody immobilization, formats of antibodies, types of cancer-associated antigens, and anticancer mechanisms of antibody-containing nanomedicines are provided and discussed in this review, with an emphasis on the latest applications. The current limitations and future research directions on antibody-containing nanomedicines are also discussed from different perspectives to provide new insights into the construction of anticancer nanomedicines.

Genetic Association Analysis of Anti-VEGF Treatment Response in Neovascular Age-Related Macular Degeneration

Anti-VEGF treatment for neovascular age-related macular degeneration (nAMD) has been FDA-approved in 2004, and since then has helped tens of thousands of patients worldwide to preserve vision. Still, treatment responses vary widely, emphasizing the need for genetic biomarkers to robustly separate responders from non-responders. Here, we report the findings of an observational study compromising 179 treatment-naïve nAMD patients and their reaction to treatment after three monthly doses of anti-VEGF antibodies. We show that established criteria of treatment response such as visual acuity and central retinal thickness successfully divides our cohort into 128 responders and 51 non-responders. Nevertheless, retinal thickness around the fovea revealed significant reaction to treatment even in the formally categorized non-responders. To elucidate genetic effects underlying our criteria, we conducted an undirected genome-wide association study followed by a directed replication study of 30 previously reported genetic variants. Remarkably, both approaches failed to result in significant findings, suggesting study-specific effects were confounding the present and previous discovery studies. Of note, all studies so far are greatly underpowered, hampering interpretation of genetic findings. In consequence, we highlight the need for an extensive phenotyping study with sample sizes exceeding at least 15,000 to reliably assess anti-VEGF treatment responses in nAMD.

Differences in Vitreous Protein Profiles in Patients With Proliferative Diabetic Retinopathy Before and After Ranibizumab Treatment

Proliferative diabetic retinopathy (PDR) accounts for severe impact on vision, its mechanism is still poorly understood. To compare the differences of vitreous protein profiles in PDR patients before and after a complete anti-vascular endothelial growth factor (VEGF) loading dose with ranibizumab treatment. Twelve vitreous humor (VH) samples were collected from six PDR patients before (set as pre group) and after (set as post group) intravitreal injection of ranibizumab (IVR) treatment. LC-MS/MS and bioinformatics analysis were performed to identify differentially expressed proteins. Proteins were validated with targeted proteomics using parallel reaction monitoring (PRM) in a validation set consisting of samples from the above patients. A total of 2680 vitreous proteins were identified. Differentially expressed proteins were filtrated with fold change ≥2.0 (post group/ pre group protein abundance ratio ≥2 or ≤ 0.5) and p-value <0.05. 11 proteins were up-regulated and 17 proteins were down-regulated, while consistent presence/absence expression profile group contains one elevated protein and nine reduced proteins, among which seven proteins were identified as potential biomarkers for IVR treatment through PRM assays. Bioinformatics analysis indicated the up-regulated proteins were significantly enriched in "GnRH secretion" and "Circadian rhythm" signaling pathway. This report represents the first description of combined label-free quantitative proteomics and PRM analysis of targeted proteins for discovery of different proteins before and after IVR treatment in the same patient. IVR treatment may protect against PDR by promoting SPP1 expression through "GnRH secretion" and "Circadian rhythm" signaling pathway.

SIRT1: Genetic Variants and Serum Levels in Age-Related Macular Degeneration

Background: The aim of this paper was to determine the frequency of SIRT1 rs3818292, rs3758391, rs7895833 single nucleotide polymorphism genotypes and SIRT1 serum levels associated with age-related macular degeneration (AMD) in the Lithuanian population. Methods: Genotyping of SIRT1 rs3818292, rs3758391 and rs7895833 was performed using RT-PCR. SIRT1 serum level was determined using the ELISA method. Results: We found that rs3818292 and rs7895833 were associated with an increased risk of developing exudative AMD. Additional sex-differentiated analysis revealed only rs7895833 was associated with an increased risk of developing exudative AMD in women after strict Bonferroni correction. The analysis also revealed that individuals carrying rs3818292, rs3758391 and rs7895833 haplotype G-T-G are associated with increased odds of exudative AMD. Still, the rare haplotypes were associated with the decreased odds of exudative AMD. After performing an analysis of serum SIRT1 levels and SIRT1 genetic variant, we found that carriers of the SIRT1 rs3818292 minor allele G had higher serum SIRT1 levels than the AA genotype. In addition, individuals carrying at least one SIRT1 rs3758391 T allele also had elevated serum SIRT1 levels compared with individuals with the wild-type CC genotype. Conclusions: Our study showed that the SIRT1 polymorphisms rs3818292 and rs7895833 and rs3818292-rs3758391-rs7895833 haplotype G-T-G could be associated with the development of exudative AMD. Also, two SNPs (rs3818292 and rs3758391) are associated with elevated SIRT1 levels.

Dry Eye and Meibomian Gland Dysfunction in Neovascular Age-Related Macular Degeneration Patients Treated with Intravitreal Injections

Objectives:

To determine if patients treated with multiple intravitreal injections for neovascular age-related macular degeneration are more likely to suffer from dry eye and meibomian gland dysfunction.

Materials and Methods:

Sixty eyes of 30 patients were enrolled. One eye of each patient was treated with multiple monthly intravitreal injections for neovascular AMD (Group 1) and the fellow healthy eye received no treatment (Group 2). The presence of dry eye was evaluated using tear film break-up time, Schirmer 1 test, the Oxford scale, and Ocular Surface Disease Index (OSDI). The loss rate of meibomian glands was evaluated by meibography and was graded and scored (meiboscore) from grade 0 (no loss of glands) to grade 3 (loss of >2/3 of total meibomian glands) for each eyelid.

Results:

Group 1 had lower mean Schirmer 1 and tear film break up-time measurements and higher mean OSDI score than Group 2, but the differences were not statistically significant (p=0.257, p=0.113, and p=0.212, respectively). Mean Oxford scale scores and meiboscore of the upper eyelids showed no statistically significant difference between the groups (p=0.594, p=0.663, respectively). The meiboscore of the lower eyelids was significantly higher in Group 1 (p=0.048).

Conclusion:

Multiple factors such as povidone-iodine and the preservatives in topical eye drops may cause inflammation leading to ocular surface damage in patients treated with multiple intravitreal injections. As the treatment requires repeated injections, exposure to these factors might worsen the ocular surface inflammation. The possibility of dry eye and meibomian gland dysfunction should be considered in these patients.

Biomarkers as Predictive Factors of Anti-VEGF Response

Age-related macular degeneration is the main cause of irreversible vision in developed countries, and intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections are the current gold standard treatment today. Although anti-VEGF treatment results in important improvements in the course of this disease, there is a considerable number of patients not responding to the standardized protocols. The knowledge of how a patient will respond or how frequently retreatment might be required would be vital in planning treatment schedules, saving both resource utilization and financial costs, but today, there is not an ideal biomarker to use as a predictive response to ranibizumab therapy. Whole blood and blood mononuclear cells are the samples most studied; however, few reports are available on other important biofluid samples for studying this disease, such as aqueous humor. Moreover, the great majority of studies carried out to date were focused on the search for SNPs in genes related to AMD risk factors, but miRNAs, proteomic and metabolomics studies have rarely been conducted in anti-VEGF-treated samples. Here, we propose that genomic, proteomic and/or metabolomic markers could be used not alone but in combination with other methods, such as specific clinic characteristics, to identify patients with a poor response to anti-VEGF treatment to establish patient-specific treatment plans.

Targeting Ocular Drug Delivery: An Examination of Local Anatomy and Current Approaches

Ocular drug delivery remains the focus of much modern research. Primary routes of administration include the surface, the intravitreal space, the subretinal space, and the subconjunctival space, each with its own series of unique challenges, limitations, and advantages. Each of these approaches requires careful consideration of the local anatomy, physical barriers, and key cells as well as the interface between the anatomy and the drug or drug system being delivered. While least invasive, the topical route poses a challenge with the many physical barriers that prevent drug penetration into the eye; while injection into the intravitreal, subretinal, and subconjunctival spaces are direct and targeted but limited due to the many internal clearance mechanisms and potential for damage to the eye. Polymeric-based, sustained-release drug delivery systems have been identified as a potential solution to many of these challenges; however, the design and successful implementation of a sustained-release system that is well-tolerated, bioactive, biocompatible, and degradable remains, in many cases, only in the early stages. The drugs and biomaterials in question also require special attention as small chemical changes could result in vastly different outcomes. This paper explores the anatomy and key cells of these four primary drug delivery routes as well as the interface between drug and drug delivery systems and the anatomy, reviewing the recent developments and current state of research in each area. Finally, this paper also examines the frequently used drugs and biomaterials found in ocular drug delivery and summarizes the primary interactions observed.