Loss of reactivity in intravitreal anti-VEGF therapy: tachyphylaxis or tolerance?

Switching to the aflibercept (3 mg) therapy for treatment-resistant wet age-related macular degeneration: 1-year outcomes

This study aimed to elucidate 1-year outcomes following switching to the aflibercept (3 mg) therapy for treatment-resistant wet age-related macular degeneration (wAMD). In this prospective, open-label, non-controlled clinical trial, 18 patients with wAMD who had multiple recurrences or persistent exudation despite intravitreal injections of anti-vascular endothelial growth factor agents (except aflibercept) received a 3-mg intravitreal aflibercept injection every 4 weeks. Each patient received 3 to 8 injections. The central retinal thickness and fibrovascular pigment epithelial detachment height decreased significantly at 1 month after initiation of the aflibercept injection, and the values were 146 and 163.2 μm, respectively, at the final visit. The morphological improvement was sustained. The intraretinal and subretinal fluid was completely absorbed at the end of the follow-up. The logMAR vision increased from baseline 0.68 to 0.59 (P < .05). No ocular or systemic adverse events occurred. The intravitreal injection of 3-mg aflibercept seems to be feasible in the treatment of wAMD unresponsive to other anti-vascular endothelial growth factor agents.

Short-Term Outcomes of Faricimab in Patients with Neovascular Age-Related Macular Degeneration on Prior Anti-VEGF Therapy

PURPOSE

A subset of patients with neovascular age-related macular degeneration (nAMD) experience treatment burden and suboptimal response with anti-VEGF therapy. The aim of this study was to investigate the effect of switching to a novel, bispecific agent, faricimab, in patients with nAMD currently treated with anti-VEGF.

DESIGN

Retrospective, noncomparative cohort study.

SUBJECTS

Patients with nAMD previously treated with anti-VEGF and switched to intravitreal faricimab injection (IFI) at the Cleveland Clinic's Cole Eye Institute.

METHODS

Switching and administration schedule of IFI was at the discretion of the clinician. Visual acuity (VA) and macular OCT parameters, including central subfield thickness (CST), maximum pigment epithelial detachment (PED) height, and presence of subretinal (SRF) or intraretinal fluid (IRF), were assessed at baseline (day of first IFI) and after each IFI.

MAIN OUTCOME MEASURES

Central subfield thickness and presence of IRF or SRF after ≥ 3 IFIs.

RESULTS

One hundred twenty-six eyes of 106 patients were included in the analysis with a mean follow-up time of 24.3 ± 5.2 weeks. Before switching to IFI, patients received a mean of either aflibercept (20.0 ± 8.4, mean ± standard deviation), bevacizumab (7 ± 8.9), ranibizumab (1.9 ± 8.5), or brolucizumab (0.3 ± 1.6) injections. The most common agent used before switching to IFI was aflibercept (n = 110, 87%), and the mean treatment interval with any anti-VEGF was 5.6 ± 1.6 weeks before switching. Central subfield thickness was reduced from baseline after the first IFI (266.8 ± 64.7 vs. 249.8 ± 58.6 μm, P = 0.02) and persisted over the 3 IFIs (P = 0.01). Pigment epithelial detachment height was reduced after the third IFI (249.6 ± 179.0 vs. 206.9 ± 130.0 μm, P = 0.01). The mean VA (62.9 vs. 62.7 approximate ETDRS letters, P = 0.42) and interval between injections (6.3 vs. 5.7 weeks, P = 0.16) was similar after the third IFI compared with baseline. Eleven (8.7%) eyes were switched back to their previous anti-VEGF, including 2 (1.6%) eyes from 1 patient with intraocular inflammation requiring cessation of IFI. There were no other adverse events from switching.

CONCLUSIONS

Switching to faricimab resulted in a reduction in mean CST (-11.6 μm, P = 0.01) and PED height (-44.2 μm, P = 0.01) after 3 injections, with stable VA and at a similar treatment interval to prior anti-VEGF therapy.

FINANCIAL DISCLOSURE(S)

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

Epigallocatechin-3-Gallate, an Active Green Tea Component to Support Anti-VEGFA Therapy in Wet Age-Related Macular Degeneration

Age-related macular degeneration (AMD) is a largely incurable disease and an emerging problem in aging societies. It occurs in two forms, dry and wet (exudative, neovascular), which may cause legal blindness and sight loss. Currently, there is not any effective treatment for dry AMD. Meanwhile, repeated intravitreal injections with antibodies effective against vascular endothelial growth factor A (VEGFA) slow down wet AMD progression but are not free from complications. (-)-Epigallocatechin-3-gallate (EGCG) is an active compound of green tea, which exerts many beneficial effects in the retinal pigment epithelium and the neural retina. It has been reported to downregulate the VEGFA gene by suppressing its activators. The inhibition of mitogen-activated protein kinases 1 and 3 (MAPK1 and MAPK3) may lie behind the antiangiogenic action of EGCG mediated by VEGFA. EGCG exerts protective effects against UV-induced damage to retinal cells and improves dysfunctional autophagy. EGCG may also interact with the mechanistic target rapamycin (MTOR) and unc-51-like autophagy activating kinase (ULK1) to modulate the interplay between autophagy and apoptosis. Several other studies report beneficial effects of EGCG on the retina that may be related to wet AMD. Therefore, controlled clinical trials are needed to verify whether diet supplementation with EGCG or green tea consumption may improve the results of anti-VEGFA therapy in wet AMD.

Pharmacotherapy and Nutritional Supplements for Neovascular Eye Diseases

In this review, we aim to provide an overview of the recent findings about the treatment of neovascular retinal diseases. The use of conventional drugs and nutraceuticals endowed with antioxidant and anti-inflammatory properties that may support conventional therapies will be considered, with the final aim of achieving risk reduction (prevention) and outcome improvement (cooperation between treatments) of such sight-threatening proliferative retinopathies. For this purpose, we consider a medicinal product one that contains well-defined compound(s) with proven pharmacological and therapeutic effects, usually given for the treatment of full-blown diseases. Rarely are prescription drugs given for preventive purposes. A dietary supplement refers to a compound (often an extract or a mixture) used in the prevention or co-adjuvant treatment of a given pathology. However, it must be kept in mind that drug-supplement interactions may exist and might affect the efficacy of certain drug treatments. Moreover, the distinction between medicinal products and dietary supplements is not always straightforward. For instance, melatonin is formulated as a medicinal product for the treatment of sleep and behavioral problems; at low doses (usually below 1 mg), it is considered a nutraceutical, while at higher doses, it is sold as a psychotropic drug. Despite their lower status with respect to drugs, increasing evidence supports the notion of the beneficial effects of dietary supplements on proliferative retinopathies, a major cause of vision loss in the elderly. Therefore, we believe that, on a patient-by-patient basis, the administration of nutraceuticals, either alone or in association, could benefit many patients, delaying the progression of their disease and likely improving the efficacy of pharmaceutical drugs.

Pharmacokinetic and Pharmacodynamic Rationale for Extending VEGF Inhibition Increasing Intravitreal Aflibercept Dose

BACKGROUND

The effects of various dosages and treatment regimens on intravitreal aflibercept concentrations and the proportion of free vascular endothelial growth factor (VEGF) to total VEGF were evaluated using a drug and disease assessment model. The 8 mg dosage received specific attention.

METHODS

A time-dependent mathematical model was developed and implemented using Wolfram Mathematica software v12.0. This model was used to obtain drug concentrations after multiple doses of different aflibercept dosages (0.5 mg, 2 mg, and 8 mg) and to estimate the time-dependent intravitreal free VEGF percentage levels. A series of fixed treatment regimens were modeled and evaluated as potential clinical applications.

RESULTS

The simulation results indicate that 8 mg aflibercept administered at a range of treatment intervals (between 12 and 15 weeks) would allow for the proportion of free VEGF to remain below threshold levels. Our analysis indicates that these protocols maintain the ratio of free VEGF below 0.001%.

CONCLUSIONS

Fixed q12-q15 (every 12-15 weeks) 8 mg aflibercept regimens can produce adequate intravitreal VEGF inhibition.

Treatment of neovascular age-related macular degeneration: insights into drug-switch real-world from the Berlin Macular Registry

PURPOSE

Bevacizumab, ranibizumab, and aflibercept are commonly used to treat neovascular age-related macular degeneration (nAMD). The results of various interventional, mostly randomized head-to-head studies, indicate statistical non-inferiority of these three drugs. The results of these studies are often interpreted as the three drugs being freely interchangeable, resulting in some health systems to pressure ophthalmologists to preferentially use the less expensive bevacizumab. This study analyzes switching from aflibercept or ranibizumab to bevacizumab and back under real-world conditions in order to investigate the assumption of interchangeability of the drugs.

METHODS

Treatment data of IVT patients with diagnosed nAMD were extracted from the clinical Berlin Macular Registry database. Patients who underwent a drug switch from aflibercept or ranibizumab to bevacizumab were subject of this study. Statistical comparisons were pre-planned for best corrected visual acuity, central retinal thickness, macular volume, and length of injection interval. Additional endpoints were analyzed descriptively.

RESULTS

Mean visual acuity decreased from 0.57 ± 0.05 under aflibercept/ranibizumab to 0.68 ± 0.06 logMAR after the switch (P = 0.001; N = 63). CRT increased from 308 ± 11 µm to 336 ± 16 µm (P = 0.011; N = 63). About half of the subjects were switched back: visual acuity increased from 0.69 ± 0.08 logMAR to 0.58 ± 0.09 logMAR (N = 26). CRT decreased from 396 ± 28 to 337 ± 20 µm (N = 28).

CONCLUSION

The data provides real-world evidence that there is loss of visual acuity and an increase in retinal edema after switching to bevacizumab. Thus, the assumption of free interchangeability cannot be confirmed in this cohort.

Retrospective analysis of the efficacy of early switching from bevacizumab to aflibercept or ranibizumab in diabetic macular edema

PURPOSE

The study aimed to compare the anatomical and functional gains of switching to ranibizumab or aflibercept in eyes with treatment-naive diabetic macular edema (DME) which has an inadequate response to three consecutive bevacizumab injections.

METHODS

This observational, retrospective, comparative study presented 12-month results of 80 patients with DME. One eye of each patient was enrolled, and bevacizumab was switched as aflibercept (40 eyes) or ranibizumab (40 eyes). DME was diagnosed based on a fundoscopic examination, fundus fluorescein angiography (FFA), central macular thickness (CMT), and best-corrected visual acuity (BCVA).

RESULTS

Forty-one patients (51.2%) were male, and 39 (48.8%) were female, with a mean age of 62.3 ± 6.7 years. At the end of the study, the mean number of intravitreal injections was 8.1 ± 1.8 in the aflibercept group, whereas 8.9 ± 1.4 in the ranibizumab (p = 0.091). The mean CMT decreased from 449.2 ± 69.3 µm to 311.0 ± 48.9 µm in the aflibercept group, and from 444.9 ± 109.2 µm to 316.3 ± 54.5 µm in the ranibizumab group (for both, p < 0.0001). The mean BVCA increased from 49.2 ± 11.1 ETDRS letters to 62.5 ± 9.9 in the aflibercept group (p < 0.0001) and from 49.9 ± 12.0 ETDRS letters to 61.1 ± 9.1 in the ranibizumab group (p < 0.0001). Macular laser treatment was required in 17.5% of the aflibercept group and 22.5% of the ranibizumab group (p = 0.781).

CONCLUSION

Significant improvement was observed with ranibizumab and aflibercept treatments in initial bevacizumab-resistant DME. Early switching therapy may contribute to better visual and anatomical outcomes.

Peptide Lv augments intermediate-conductance calcium-dependent potassium channels (KCa3.1) in endothelial cells to promote angiogenesis

Peptide Lv is a small endogenous secretory peptide that is expressed in various tissues and conserved across different species. Patients with diabetic retinopathy, an ocular disease with pathological angiogenesis, have upregulated peptide Lv in their retinas. The pro-angiogenic activity of peptide Lv is in part through promoting vascular endothelial cell (EC) proliferation, migration, and sprouting, but its molecular mechanism is not completely understood. This study aimed to decipher how peptide Lv promotes EC-dependent angiogenesis by using patch-clamp electrophysiological recordings, Western immunoblotting, quantitative PCR, and cell proliferation assays in cultured ECs. Endothelial cells treated with peptide Lv became significantly hyperpolarized, an essential step for EC activation. Treatment with peptide Lv augmented the expression and current densities of the intermediate-conductance calcium-dependent potassium (KCa3.1) channels that contribute to EC hyperpolarization but did not augment other potassium channels. Blocking KCa3.1 attenuated peptide Lv-elicited EC proliferation. These results indicate that peptide Lv-stimulated increases of functional KCa3.1 in ECs contributes to EC activation and EC-dependent angiogenesis.

Metformin therapy as a strategy to compensate anti-VEGF resistance in patients with diabetic macular edema

Diabetic macular edema (DME) is the complication of diabetic retinopathy, the leading cause of vision loss among diabetic patients. Metformin is the main antidiabetic treatment. It is preferable for its great anti-angiogenic and anti-inflammatory effects. Anti-vascular endothelial growth factor (VEGF) therapy is the preferable treatment for DME despite its lack of convincing results in some patients. To assess whether the combination of metformin and anti-VEGF drugs may decrease the risk of anti-VEGF resistance among DME patients. We included DME patients with a central retinal thickness (CRT) ≥ 250 μm who consecutively underwent at least 3 anti-VEGF therapies from January 1, 2020, to December 30, 2021. Anti-VEGF resistance was defined as persistent macular edema with decreased CRT ≤ 25% after 3 anti-VEGF injections. 109 patients were considered for this research, of whom 65 (59.6%) were resistant to anti-VEGF therapy. The mean CRT of the non-metformin group decreased from 344.88 ± 129.48 to 318.29 ± 123.23 (20.85%) and from 415.64 ± 144.26 to 277.11 ± 99.25 (31.51%) (P = .031) in the metformin group. Moreover, the metformin group had fewer resistant patients than the non-metformin, 24 (45.3%) versus 41 (73.2%). Furthermore, a considerable gain in visual acuity was observed in both groups, with a BCVA gain of 40.41% in the metformin group and 39.9% in the non-metformin group. Metformin may be combined with an anti-VEGF drug to minimize the risk of anti-VEGF resistance among DME patients. Moreover, it can serve to design effective therapeutic deliveries.

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.

New anti-angiogenic compound based on chemically modified heparin

PURPOSE

The purpose of this study was to measure the anti-angiogenic effect of N-desulfated Re-N-acetylated, a chemically modified heparin (mHep).

METHODS

In vitro assays (cell tube formation, viability, proliferation, and migration) with endothelial cells were performed after 24 h of treatment with mHep at 10, 100, and 1000 ng/mL or saline. In vivo tests were performed after laser-induced choroidal neovascularization (CNV) in rats, followed by an intravitreal injection (5 µL) of mHep (10, 100, 1000 ng/mL) or balanced salt solution. Immunofluorescence analysis of the CNV was performed after 14 days.

RESULTS

mHep produced a statistically significant reduction in cell proliferation, tube formation, and migration, without cell viability changes when compared to saline. Mean measures of CNV area were 54.84 × 10⁶ pixels/mm (± 12.41 × 10⁶), 58.77 × 10⁶ pixels/mm (± 17.52 × 10⁶), and 59.42 × 10⁶ pixels/mm (± 17.33 × 10⁶) in groups 100, 1000, and 10,000 ng/mL, respectively, while in the control group, mean area was 72.23 × 10⁶ (± 16.51 × 10⁶). The P value was 0.0065. Perimeter analysis also demonstrated statistical significance (P = 0.0235) with the mean measure of 93.55 × 10⁴, 94.23 × 10⁴, and 102 × 10⁴ in the 100 ng/mL, 1000 ng/mL, and control groups, respectively.

CONCLUSIONS

These results suggest that mHep N-DRN is a potent anti-angiogenic, anti-proliferative, and anti-migratory compound with negligible anticoagulant or hemorrhagic action and no cytotoxicity for retina cells. This compound may serve as a candidate for treating choroidal neovascularization.

Elastin turnover in ocular diseases: A special focus on age-related macular degeneration

The extracellular matrix (ECM) and its turnover play a crucial role in the pathogenesis of several inflammatory diseases, including age-related macular degeneration (AMD). Elastin, a critical protein component of the ECM, not only provides structural and mechanical support to tissues, but also mediates several intracellular and extracellular molecular signaling pathways. Abnormal turnover of elastin has pathological implications. In the eye elastin is a major structural component of Bruch's membrane (BrM), a critical ECM structure separating the retinal pigment epithelium (RPE) from the choriocapillaris. Reduced integrity of macular BrM elastin, increased serum levels of elastin-derived peptides (EDPs), and elevated elastin antibodies have been reported in AMD. Existing reports suggest that elastases, the elastin-degrading enzymes secreted by RPE, infiltrating macrophages or neutrophils could be involved in BrM elastin degradation, thus contributing to AMD pathogenesis. EDPs derived from elastin degradation can increase inflammatory and angiogenic responses in tissues, and the elastin antibodies are shown to play roles in immune cell activity and complement activation. This review summarizes our current understanding on the elastases/elastin fragments-mediated mechanisms of AMD pathogenesis.

Genetic Variants of Complement Factor H Y402H (rs1061170), C2 R102G (rs2230199), and C3 E318D (rs9332739) and Response to Intravitreal Anti-VEGF Treatment in Patients with Exudative Age-Related Macular Degeneration

Background and Objectives: To assess the association between the single nucleotide polymorphisms (SNPs) in the genes encoding complement factors CFH, C2, and C3 (Y402H rs1061170, R102G rs2230199, and E318D rs9332739, respectively) and response to intravitreal anti-vascular endothelial growth factor (VEGF) therapy in patients with exudative age-related macular degeneration (AMD). Materials and Methods: The study included 111 patients with exudative AMD treated with intravitreal bevacizumab or ranibizumab injections. Response to therapy was assessed on the basis of best-corrected visual acuity (BCVA) and central retinal thickness (CRT) measured every 4 weeks for 12 months. The control group included 58 individuals without AMD. The SNPs were genotyped by a real-time polymerase chain reaction in genomic DNA isolated from peripheral blood samples. Results: The CC genotype in SNP rs1061170 of the CFH gene was more frequent in patients with AMD than in controls (p = 0.0058). It was also more common among the 28 patients (25.2%) with poor response to therapy compared with good responders (p = 0.0002). Poor responders, especially those without this genotype, benefited from switching to another anti-VEGF drug. At the last follow-up assessment, carriers of this genotype had significantly worse BCVA (p = 0.0350) and greater CRT (p = 0.0168) than noncarriers. TT genotype carriers showed improved BCVA (p = 0.0467) and reduced CRT compared with CC and CT genotype carriers (p = 0.0194). No associations with AMD or anti-VEGF therapy outcomes for SNP rs9332739 in the C2 gene and SNP rs2230199 in the C3 gene were found. Conclusions: The CC genotype for SNP rs1061170 in the CFH gene was associated with AMD in our population. Additionally, it promoted a poor response to anti-VEGF therapy. On the other hand, TT genotype carriers showed better functional and anatomical response to anti-VEGF therapy at 12 months than carriers of the other genotypes for this SNP.

Switching between anti-VEGF agents in the management of refractory diabetic macular edema: A systematic review

Refractory diabetic macular edema (DME) to monthly intravitreal anti-vascular endothelial growth factor (VEGF) monotherapy has a prevalence of approximately 40% in landmark clinical trials. Options for these patients include use of intravitreal steroids, focal laser, or switching to an alternative anti-VEGF agent. We summarize the key conclusions from studies analyzing the efficacy of switching anti-VEGF agents for refractory DME. Twenty-four studies were included in analysis. The most common definitions of refractory in the included studies were a central retinal thickness (CRT) greater than 300μm or a reduction in CRT less than 10% after at least 3-6 prior anti-VEGF injections. Switching to intravitreal aflibercept (IVA) from either intravitreal ranibizumab (IVR) or bevacizumab (IVB) is associated with moderate to significant improvement in central subfield thickness and may be an appropriate choice for patients with refractory DME. The improvement in retinal thickness and edema is typically seen after the first 3 injections of IVA post-switch. Switching to IVR has also demonstrated improvement in CRT at 3-6 months post-switch in large sample population studies. Future studies are required to elucidate the ideal time point for a switch in anti-VEGF agent or which patients would benefit from this change.

Anatomical and functional responses to single brolucizumab injection in neovascular age-related macular degeneration patients not responding to antiangiogenics: a case series

Introduction:

Neovascular age-related macular degeneration (nAMD) is treated with antivascular endothelial growth factor (anti-VEGF) drugs. However, resistance to anti-VEGF therapy is observed in some patients. Brolucizumab is a new-generation anti-VEGF drug for the treatment of nAMD, with proven efficacy in fluid resolution and long-lasting effects.

Methods:

We report here a case series of nAMD patients not responding to previous anti-VEGF therapy showing anatomical and functional response to a single intravitreal injection of brolucizumab.

Results:

Nine patients with nAMD, undergoing treatment with anti-VEGF therapy (aflibercept, bevacizumab, or ranibizumab) but with either fluid persistence or frequent fluid recurrences in retinal compartments, were switched to intravitreal brolucizumab and examined 4 weeks postinjection. No signs of active disease were observed in all but one patient, with complete retinal fluid resolution in seven patients. Central macular thickness and visual acuity significantly improved, and changes were sustained for up to 12 weeks in a subset of three patients. No adverse reactions were observed.

Conclusions:

This new anti-VEGF drug showed great efficacy since the first week from the injection with a significative reduction of subretinal fluid and rapid improvement of visual acuity. In conclusion, brolucizumab administered intravitreally appears to be an effective treatment in nAMD patients, leading to both early anatomical and functional improvements.

Novel Possible Protein Targets in Neovascular Age-Related Macular Degeneration: A Pilot Study Experiment

Age-related macular degeneration (AMD) is among the world's leading causes of blindness. In its neovascular form (nAMD), around 25% of patients present further anatomical and visual deterioration due to persistence of neovascular activity, despite gold-standard treatment protocols using intravitreal anti-VEGF medications. Thus, to comprehend, the molecular pathways that drive choroidal neoangiogenesis, associated with the vascular endothelial growth factor (VEGF), are important steps to elucidate the mechanistic events underneath the disease development. This is a pilot study, a prospective, translational experiment, in a real-life context aiming to evaluate the protein profiles of the aqueous humor of 15 patients divided into three groups: group 1, composed of patients with nAMD, who demonstrated a good response to anti-VEGF intravitreal injections during follow-up (good responsive); group 2, composed of patients with anti-VEGF-resistant nAMD, who demonstrated choroidal neovascularization activity during follow-up (poor/non-responsive); and group 3, composed of control patients without systemic diseases or signs of retinopathy. For proteomic characterization of the groups, mass spectrometry (label-free LC-MS/MS) was used. A total of 2,336 proteins were identified, of which 185 were distinctly regulated and allowed the differentiation of the clinical conditions analyzed. Among those, 39 proteins, including some novel ones, were analyzed as potential disease effectors through their pathophysiological implications in lipid metabolism, oxidative stress, complement system, inflammatory pathways, and angiogenesis. So, this study suggests the participation of other promising biomarkers in neovascular AMD, in addition to the known VEGF.

Results of the switch from intravitreal ranibizumab to intravitreal aflibercept therapy in patients with neovascular age-related macular degeneration: A 42-month retrospective real-world study

Aim

The study aimed to evaluate the functional and anatomical results of patients treated with intravitreal ranibizumab (IVR) for neovascular age-related macular degeneration (n-AMD) but switched to intravitreal aflibercept (IVA) treatment due to insufficient response treatment.

Material and Methods

At least six doses of n-AMD were administered IVR to 33 patients who were switched to IVA treatment due to insufficient response and were included in the study. The patients were evaluated at the beginning of the IVR treatment during the transition to IVA treatment and at 6, 12, 18, 24, 30, 36, and 42 months of IVA treatment.

Results

After an average of 10.1 ± 5.04 IVR injections, the patients who were accepted as insufficient response were treated with IVA. The central macular thickness of the patients was evaluated at the beginning of the treatment, immediately before, and after the initiation of IVA treatment at 6, 12, 18, 24, 30, 36, 42 months. It was as follows: 325.21 ± 123.04, 351.42 ± 126.09, 284.81 ± 112.65, 296.68 ± 89.17, 282.61 ± 81.58, 292.27 ± 109, 92,269.75 ± 97.14, 267.50 ± 87.56, and 266.82 ± 88.35 μm. According to the best-corrected visual acuity (BCVA), it was initially 0.89 ± 0.65; 1.08 ± 0.53 during the transition to IVA; 0.91 ± 0.46 6 months after IVA; 12^th 1.14 ± 0.59; 0.94 ± 0.55 at 18^th; 1.07 ± 0.49 at 24^th; 1.15 ± 0.57 at 30^th; 1.06 ± 0.45 at 36^th, and 1.13 ± 0.46 LogMAR ( Logarithm of the Minimum Angle of Resolution) at the 42^nd month.

Conclusion

In conclusion, in n-AMD patients with inadequate response to intravitreal ranibizumab or with relapse, and therefore, switched to aflibercept treatment, the anatomical improvement and sustainment were observed, however, functional recovery could not be achieved.

[Anti-VEGF therapy for neovascular age-related macular degeneration: causes of incomplete response]

Neovascular age-related macular degeneration (nAMD) is one of the leading causes of decreased vision in the elderly population in many countries, including Russia. Anti-VEGF therapy is undoubtedly the «gold standard» of treatment for the disease, but its use in different patients is known to produce results with significant interindividual differences. This article reviews modern ideas about the clinical assessment of the degree of response to anti-VEGF therapy, possible reasons for its insufficient effectiveness (clinical, pharmacological, or related to nAMD pathogenesis), discusses the potential applications of the existing therapeutic strategies, and considers the prospects for the emergence of new strategies that could be used for solving that problem.

Exacerbation of pigment epithelial detachment following aflibercept: A case of bevacizumab rescue

Purpose

We describe a 61-year-old female patient with a retinal pigment epithelial detachment (PED) of the left eye in the setting of neovascular aged-macular degeneration (nAMD) with unanticipated responses to aflibercept and bevacizumab.

Observations

A reduction of PED size from 423 μm to 309 μm and vision improvement (20/150- to 20/40) were observed after five consecutive monthly injections of bevacizumab. A switch to aflibercept for the following two consecutive months showed an unanticipated incremental decline in vision (20/80- at month 1, 20/150- at month 2), increased PED size (749 μm), and the development of subretinal fluid (SRF). After a switch back to bevacizumab, the subretinal fluid resolved. After nine consecutive monthly injections of bevacizumab, final vision in the left eye was 20/25, and final PED height was 84 μm.

Conclusions

Different anti-VEGFs may induce varied and unpredictable responses among the most recalcitrant cases of nAMD. Unpredictably, PED size in our patient worsened with aflibercept treatment.

Importance

Treatment for nAMD with large PEDs has poor level 1 evidence for guidance, and customized treatment should be considered.

Short-Term Outcomes following "Switching" to Monthly Ranibizumab in Neovascular Age-Related Macular Degeneration Showing Insufficient Response to Bimonthly Aflibercept

Results

CRT and logMAR VA were 349.62 ± 223.51 μm and 0.50 ± 0.23 at the baseline and 274.69 ± 148.77 μm and 0.46 ± 0.24, 311.54 ± 192.90 μm and 0.45 ± 0.20 at 1 month after the first and third ranibizumab injections, respectively. The CRT decrease during three ranibizumab injections was statistically significant (38.08 ± 69.52 μm, p=0.033). Change in VA was not statistically significant. The percentage of eyes with SRF was 100% at baseline and 53.8%, 76.9%, and 69.2% one month after each ranibizumab injections. The percentage of eyes with IRF was 38.5% at baseline and 23.1%, 23.1%, and 15.4%, respectively, after switching.

Conclusion

Switching to monthly ranibizumab in nAMD showing an insufficient response to bimonthly aflibercept led to immediate anatomical improvement. It can be considered in countries where the healthcare insurance system limits the minimum injection interval of aflibercept.

Retrospective Analysis of Treatment Patterns in Pseudophakic Diabetic Macular Oedema Eyes Treated with Anti-VEGF

Methods

We performed a retrospective review of outcomes in 81 pseudophakic eyes with DMO that received at least 6 anti-VEGF injections. We reviewed baseline and posttreatment optical coherence tomography images, visual acuity, prescribing patterns, time taken to deliver anti-VEGF injections, and structural and functional outcomes.

Results

It took an average of 913 ± 454.1 days to deliver a mean of 11.1 ± 4.7 anti-VEGF injections. Time from baseline to receiving the first 6 anti-VEGF injections was longer than 9 months in 74.7% (n = 59/79) of eyes. There was a mean gain of 1.6 letters (−0.03 logMAR) from baseline to the end point. After 5 anti-VEGF intravitreal injections, the mean CMT was 391.9 μm from 474.4 μm at baseline (p < 0.0001). In 52 of 79 eyes (65.8%), more than one type of anti-VEGF agent was used.

Conclusions

The anti-VEGF treatment used to treat these eyes with DMO was suboptimal, a finding consistent with recently published “real-world” data. There was a strong tendency for patients to be switched within the class to a second anti-VEGF agent.

VEGFR2 Trafficking by KIF13B Is a Novel Therapeutic Target for Wet Age-Related Macular Degeneration

Purpose

Vascular endothelial growth factor (VEGF) and its receptor VEGFR2 are promising therapeutic targets for wet age-related macular degeneration (AMD). As a topically applicable option, we developed the peptide KAI to selectively interfere with VEGFR2 trafficking to the cell surface where it receives VEGF. This study sought to determine the efficacy of KAI in the mouse model of choroidal neovascularization (CNV).

Methods

The specificity of KAI was tested by surface plasmon resonance. The drug delivery was analyzed by cryosection and the ELISA after treatment of KAI eyedrop to the mouse eyes. For the laser-induced CNV model, mice with laser-induced ruptures in Bruch's membrane received daily treatment of KAI eyedrop or control peptide. The other groups of mice received intravitreal injection of anti-VEGF or IgG control. After two weeks, CNV was quantified and compared.

Results

First, we showed the specificity and high affinity of KAI to VEGFR2. Next, biodistribution revealed successful delivery of KAI eyedrop to the back of the mouse eyes. KAI significantly reduced the disease progression in laser-induced CNV. The comparison with current therapy suggests that KAI eyedrop is as effective as current therapy to prevent CNV in wet AMD. Moreover, the genetic deletion of a kinesin KIF13B, which mediates VEGFR2 trafficking to the cell surface, confirmed the pivotal role of KIF13B in disease progression of wet AMD and neovascularization from choroidal vessels.

Conclusions

Taken together, pharmacologic inhibition and genetic deletion complementarily suggest the therapeutic possibility of targeting VEGFR2 trafficking to inhibit pathological angiogenesis in wet AMD.

Comparison of Intravitreal Bevacizumab and Aflibercept Injections for Central Serous Chorioretinopathy

Purpose: We examined differences in the treatment effects of intravitreal bevacizumab injections and intravitreal aflibercept injections in patients with central serous chorioretinopathy. Methods: This retrospective analysis included 51 eyes of 49 patients who received intravitreal anti-vascular endothelial growth factor agent injections after initial diagnosis with central serous chorioretinopathy. The patients were divided into two groups: one received an intravitreal bevacizumab injection, and another one received an intravitreal aflibercept injection. Patients with no reaction to treatment or a worsened condition, received repeat treatment with the same therapy. After treatment, patients were monitored for >3 months. Data were collected regarding best- corrected visual acuity (BCVA), subfoveal choroidal thickness, injection number, and treatment duration. Results: Both intravitreal bevacizumab injections and intravitreal aflibercept injections led to significant differences in BCVA (p < 0.0001, p = 0.001) and subfoveal choroidal thickness (p < 0.0001, p = 0.011), compared between before and after treatment. However, no differences between groups were observed in mean change of BCVA or subfoveal choroidal thickness. In addition, there were no differences between groups in injection number and treatment duration. Conclusions: In patients with central serous chorioretinopathy, both intravitreal bevacizumab injections and intravitreal aflibercept injections are effective treatment methods. There were no differences between the two medicines in terms of functional and anatomical recovery, or the injection number and treatment duration.

CD160 protein as a new therapeutic target in a battle against autoimmune, infectious and lifestyle diseases. Analysis of the structure, interactions and functions

The glycosylphosphatidylinositol-anchored transmembrane glycoprotein CD160 (cluster of differentiation 160) is a member of the immunoglobulin superfamily. Four isoforms, which differ by the presence or absence of an immunoglobulin-like domain and the mode of anchoring in the cell membrane, have been identified. CD160 has a significant impact on the proper functioning of the immune system by activating natural killer cells and inhibiting T cells. CD160 is a natural ligand for herpes virus entry mediator (HVEM), a member of the tumor necrosis factor superfamily. The CD160-HVEM complex is a rare example of direct interaction between the two different superfamilies. The interaction of these two proteins leads to the inhibition of CD4⁺ T cells which, in consequence, leads to the inhibition of the correct response of the immune system. Available research articles indicate that CD160 plays a role in various types of cancer, chronic viral diseases, malaria, paroxysmal nocturnal hemoglobinuria, atherosclerosis, autoimmune diseases, skin inflammation, acute liver damage and retinal vascular disease. We present here an overview of the CD160 protein, the general characteristics of the receptor and its isoforms, details of structural studies of CD160 and the CD160-HVEM complex, as well as a description of the role of this protein in selected human diseases.

Short-Term Outcomes of Refractory Diabetic Macular Edema Switch From Ranibizumab to Dexamethasone Implant and the Influential Factors: A Retrospective Real World Experience

Introduction: To evaluate the effectiveness and safety of intravitreal dexamethasone (DEX) implants in refractory diabetic macular edema (DME) treated by intravitreal ranibizumab.

Materials and Methods: We retrospectively analyzed DME patients who received DEX implant treatment after being refractory to at least 3 monthly intravitreal ranibizumab injections. The main outcomes were best-corrected visual acuity (BCVA), central retinal thickness (CRT), and intraocular pressure (IOP).

Results: Twenty-nine eyes of 26 patients who had previously received an average of 8.1 ± 4.4 ranibizumab injections were included. Patients received between one and three DEX implants during 12.4 ± 7.4 months of follow-up. The mean final CRT significantly decreased from 384.4 ± 114.4 μm at baseline to 323.9 ± 77.7 μm (p = 0.0249). The mean final BCVA was 51.4 ± 21.3 letters, which was not significant compared to baseline (44.9 ± 30.2 letters, p = 0.1149). Mean IOP did not increase significantly. All patients tolerated the treatment well without serious adverse events. Higher baseline CRT and worse BCVA correlated with better therapeutic responses.

Conclusion: Switching to DEX implant is feasible and safe for treating patients of DME refractory to intravitreal ranibizumab in real world. Further larger-scale or multicenter studies would be conducted to explore different DEX treatment strategies for DME, such as first-line or early switch therapy, for better BCVA improvement.

Cell-Matrix Interactions in the Eye: From Cornea to Choroid

The extracellular matrix (ECM) plays a crucial role in all parts of the eye, from maintaining clarity and hydration of the cornea and vitreous to regulating angiogenesis, intraocular pressure maintenance, and vascular signaling. This review focuses on the interactions of the ECM for homeostasis of normal physiologic functions of the cornea, vitreous, retina, retinal pigment epithelium, Bruch's membrane, and choroid as well as trabecular meshwork, optic nerve, conjunctiva and tenon's layer as it relates to glaucoma. A variety of pathways and key factors related to ECM in the eye are discussed, including but not limited to those related to transforming growth factor-β, vascular endothelial growth factor, basic-fibroblastic growth factor, connective tissue growth factor, matrix metalloproteinases (including MMP-2 and MMP-9, and MMP-14), collagen IV, fibronectin, elastin, canonical signaling, integrins, and endothelial morphogenesis consistent of cellular activation-tubulogenesis and cellular differentiation-stabilization. Alterations contributing to disease states such as wound healing, diabetes-related complications, Fuchs endothelial corneal dystrophy, angiogenesis, fibrosis, age-related macular degeneration, retinal detachment, and posteriorly inserted vitreous base are also reviewed.

Efficacy and safety of intravitreal aflibercept in ranibizumab-refractory patients with neovascular age-related macular degeneration

Background

Anti–vascular endothelial growth factor (anti-VEGF) agents have become the standard of care in neovascular age-related macular degeneration (nAMD). Despite generally excellent response rates to anti-VEGF therapy, some patients do not respond or may respond suboptimally. In the case of refractory or rapidly recurring fluid in nAMD, clinicians may switch to another anti-VEGF agent. TITAN was an observational study that assessed the effectiveness and safety of intravitreal aflibercept (IVT-AFL) in patients with nAMD refractory to ranibizumab who switched to IVT-AFL after less than 12 months of ranibizumab treatment in routine clinical practice in France.

Methods

TITAN was an observational, retrospective and prospective 12-month study conducted at 28 centres in France. Patients with nAMD refractory to ranibizumab were enrolled. Patients who were switched from ranibizumab to IVT-AFL were followed for 12 months. Data were obtained from medical records for retrospectively included patients, and at routine follow-up visits for those included prospectively. The main outcome measure was percentage of patients who achieved treatment success (gain of ≥1 Early Treatment Diabetic Retinopathy Study letters in best-corrected visual acuity [BCVA] and/or any reduction in central retinal thickness [CRT]) from baseline to 12 months after switching. A sample size of 225 patients was determined based on a 2-sided 95% confidence interval with a width equal to 0.12 when the sample proportion was 0.70.

Results

We analysed safety data (N = 217) and clinical outcomes from patients in the per-protocol population (n = 125). The mean (standard deviation) number of IVT-AFL injections was 7.5 (2.6). Treatment success was achieved in 68.8% of patients. Mean BCVA change from baseline to Month 12 was + 1.5 letters (P = 0.105) and the mean CRT change was − 45.0 μm (P <  0.001). In a subgroup analysis, in patients who received three initial monthly IVT-AFL injections, mean BCVA gain was 3.3 letters at Month 12 (P = 0.015). Excluding lack of efficacy and inappropriate scheduling of drug administration, the most common adverse event was eye pain (2.3%).

Conclusions

Switching ranibizumab-refractory patients with nAMD to IVT-AFL may improve visual outcomes in some patients, particularly those who receive three initial monthly injections.

Trial registration

ClinicalTrials.gov, NCT02321241. First posted: December 22, 2014; Last update posted: July 2, 2018

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-021-01841-6.

The effect of Eurycoma Longifolia on the regulation of reproductive hormones in young males

Eurycoma longifolia supplementation increases testosterone levels in humans via activation of the hypothalamic-pituitary-gonadal axis and/or the hypothalamic-pituitary-adrenal axis mainly in older adults and nonhealthy populations. This study aimed to assess the impact of Eurycoma longifolia on the hypothalamic-pituitary-gonadal and hypothalamic-pituitary-adrenal axes in healthy young males since this might promote functional testosterone prowess. Thirty-two males (24.4 ± 4.7 years; 1.74 ± 0.07 m; 73.7 ± 8.4 kg) in a placebo-controlled, double-blind, matched-paired study received 600 mg/day Eurycoma longifolia or placebo for two weeks. Blood analysis using repeated measures analysis of variance showed significant interaction and time effects for testosterone (F_1,30  = 9.04, p = .005), free testosterone (F_1,30  = 7.13, p = .012) and estradiol (F_1,30  = 8.07, p = .008) levels in favour of the treatment group, while luteinising hormone, follicle-stimulating hormone and sexual hormone-binding globulin did not. The lack of changes in luteinising hormone and follicle-stimulating hormone levels suggests that a lesser role played by Eurycoma longifolia in activating the hypothalamic-pituitary-gonadal axis in the young adults. The raised testosterone level may be due to a greater rate of hormone production via the hypothalamic-pituitary-adrenal axis. The supplementation of Eurycoma longifolia for two weeks demonstrates steroidogenic effects on young men were dose-related. Consequently, the raised testosterone following Eurycoma longifolia supplementations could benefit muscle and strength gain in young adults.

Intravitreal Ranibizumab or Aflibercept After Bevacizumab in Diabetic Macular Edema: Exploratory Retrospective Analysis

Aim

To evaluate the efficacy of switching from bevacizumab to ranibizumab or aflibercept in eyes with diabetic macular edema (DME) unresponsive to bevacizumab.

Methods

Single-center retrospective comparative study of patients with DME unresponsive to intravitreal bevacizumab that was switched to ranibizumab or aflibercept. Best-corrected visual acuity (BCVA) and central foveal thickness (CFT) were analysed prior to and 4 months after the switch. Ocular coherence tomography (OCT) biomarkers were also analysed.

Results

Fifty-six eyes from 40 patients were included in the study, 33 eyes switched to ranibizumab and 23 to aflibercept. A significant median CFT decrease was observed in both groups (p<0.001), with no between-group differences. BCVA gain was only significant in the ranibizumab group (p<0.001). None of the pre-baseline or baseline parameters were associated with the response to ranibizumab or aflibercept.

Conclusion

In persistent DME unresponsive to bevacizumab, both anatomical and functional improvements were observed with ranibizumab whereas aflibercept only showed an anatomical improvement. Clinicaltrials.gov NCT04018833.

Subgroups and Features of Poor Responders to Anti-Vascular Endothelial Growth Factor Treatment in Eyes with Neovascular Age-Related Macular Degeneration

Objectives:

This study aimed to determine the incidence of poor response to intravitreal (IV) anti-VEGF treatment in neovascular age-related macular degeneration (nvAMD) and to define subgroups of poor responders.

Materials and Methods:

A total of 235 treatment-naive eyes of 202 patients completed this prospective study. Patients younger than 50 years of age and those with a contraindication for anti-VEGF therapy were excluded. All eyes were treated with IV ranibizumab. Poor response was defined as recurrence, persistence, or worsening despite treatment. Poor responders were classified into subgroups based on progression patterns.

Results:

Of the 235 eyes, 78 (33.2%) showed poor response. Pigment epithelial detachment (PED) and occult choroidal neovascularization (CNV) were more common among poor responders (p<0.001) and 5 subgroups were identified.

Conclusion:

Poor response to anti-VEGF treatment is not uncommon and occult CNV and PED are frequently seen in these eyes. Various subgroups can be defined based on clinical features.

Short-Term Results of Switch from Conbercept to Bevacizumab or Ranibizumab in Eyes with Persistent Neovascular Age-Related Macular Degeneration

Purpose

To study the short-term anatomical and functional outcomes in patients with neovascular age-related macular degeneration (nAMD) who were previously treated with conbercept and switched to ranibizumab or bevacizumab due to persistent activity.

Methods

This retrospective single-arm study included nAMD patients who were followed up for at least three months after switching from at least 3 monthly intravitreal conbercept injections to bevacizumab or ranibizumab for persistent choroidal neovascularization (CNV) activity. The demographic data, treatments, best-corrected visual acuity (BCVA), central macular thickness (CMT), and the height of pigmented epithelial detachment (PED) before and after switching were recorded and analyzed.

Results

A total of 64 eyes of 64 patients were included with a mean follow-up of 9.6 ± 3.0 months. The average number of injections of conbercept was 3.6 ± 0.8 (range, 3–5) before switching. 18 eyes were switched to bevacizumab, and the other 46 eyes were switched to ranibizumab. After switching, mean BCVA slowly improved from 0.73 ± 0.48 to 0.64 ± 0.41 (p=0.0132) at one month after the last intravitreal injection of ranibizumab or bevacizumab during the mean follow-up of 4.4 ± 2.0 months. One month after switching, the mean CMT decreased significantly from 294.9 ± 121.8 μm to 230.9 ± 107.0 μm (p < 0.0001) and kept stable during the follow-up. There was a significant reduction of maximum PED height (mPEDH) at the first month after switching (from 384.3 ± 340.3 μm to 287.2 ± 245.2 μm, p=0.0018) and kept stable during the follow-up. The mean PED height at foveal center (cPEDH) showed a regression over time after switching (from 169.3 ± 230.6 μm to 130.5 ± 180.2 μm, p=0.0227) and also kept stable during the follow-up. The proportion of patients with IRF was slightly increased but not statistically significant before switching. After switching, this proportion decreased significantly from 96.9% to 81.3% at one month after the first intravitreal injection of ranibizumab or bevacizumab (p=0.0086). The proportion of patients with SRF did not change significantly before and after switching. The mean decrease of mPEDH and cPEDH at the last follow-up after switching was significantly larger in the IVR subgroup than in the IVB subgroup (p=0.023 and 0.010).

Conclusion

Our results indicate that switching from intravitreal conbercept injections to bevacizumab or ranibizumab can lead to significant improvement of CMT, PED, and IRF and slight improvement of BCVA in a short period of time for persistent nAMD patients.

Incomplete response to Anti-VEGF therapy in neovascular AMD: Exploring disease mechanisms and therapeutic opportunities

Intravitreal anti-vascular endothelial growth factor (VEGF) drugs have revolutionized the treatment of neovascular age-related macular degeneration (NVAMD). However, many patients suffer from incomplete response to anti-VEGF therapy (IRT), which is defined as (1) persistent (plasma) fluid exudation; (2) unresolved or new hemorrhage; (3) progressive lesion fibrosis; and/or (4) suboptimal vision recovery. The first three of these collectively comprise the problem of persistent disease activity (PDA) in spite of anti-VEGF therapy. Meanwhile, the problem of suboptimal vision recovery (SVR) is defined as a failure to achieve excellent functional visual acuity of 20/40 or better in spite of sufficient anti-VEGF treatment. Thus, incomplete response to anti-VEGF therapy, and specifically PDA and SVR, represent significant clinical unmet needs. In this review, we will explore PDA and SVR in NVAMD, characterizing the clinical manifestations and exploring the pathobiology of each. We will demonstrate that PDA occurs most frequently in NVAMD patients who develop high-flow CNV lesions with arteriolarization, in contrast to patients with capillary CNV who are highly responsive to anti-VEGF therapy. We will review investigations of experimental CNV and demonstrate that both types of CNV can be modeled in mice. We will present and consider a provocative hypothesis: formation of arteriolar CNV occurs via a distinct pathobiology, termed neovascular remodeling (NVR), wherein blood-derived macrophages infiltrate the incipient CNV lesion, recruit bone marrow-derived mesenchymal precursor cells (MPCs) from the circulation, and activate MPCs to become vascular smooth muscle cells (VSMCs) and myofibroblasts, driving the development of high-flow CNV with arteriolarization and perivascular fibrosis. In considering SVR, we will discuss the concept that limited or poor vision in spite of anti-VEGF may not be caused simply by photoreceptor degeneration but instead may be associated with photoreceptor synaptic dysfunction in the neurosensory retina overlying CNV, triggered by infiltrating blood-derived macrophages and mediated by Müller cell activation Finally, for each of PDA and SVR, we will discuss current approaches to disease management and treatment and consider novel avenues for potential future therapies.

Short-term results of early switch from Ranibizumab to Aflibercept in poor or non responder age related macular degeneration in clinical practice

BACKGROUND

To evaluate the change in best corrected visual acuity (VA) and central macular thickness (CMT) following treatment with intravitreal aflibercept (AFL) in patients poorly responders or non responders to ranibizumab (RBZ).

METHODS

Charts of patients injected with RBZ from January 2016 to December 2018 (548 cases) due to neovascular age-related macular degeneration (nAMD) were reviewed. Fifty-six cases met our criteria for poor responders to RBZ (CMT decreased between 5 and 15% over treatment) or for non responders to RBZ (CMT decreased less than 5% or increased over treatment).

RESULTS

After the third AFL injection, CMT decreased from 384.38 ± 123.20 μm to 296.18 ± 70.52 μm in the non-responder group and from 320.00 ± 82.05 μm to 282.27 ± 56.86 μm in the poor responder group. Although decrease in macular thickness was overall achieved 3 months after switching to AFL, it was not translated in VA improvement.

CONCLUSIONS

it was observed that nAMD patients classified as RBZ non-responders tend to respond better to AFL than RBZ poor-responders anatomically, without correspondent improvement in VA.

Beneficial switch from aflibercept to ranibizumab for the treatment of refractory neovascular age-related macular degeneration

Purpose

The aim of this study was to evaluate the effects of switching to ranibizumab in patients with neovascular age-related macular degeneration (nAMD) refractory to aflibercept treatment and to identify predictive factors for switch response.

Methods

A retrospective chart review was conducted including 32 eyes from 26 patients with refractory nAMD, who switched from monthly intravitreal aflibercept treatment (≥ 6 months) to ranibizumab. Outcome measures included changes in visual acuity (VA), intraretinal fluid (IRF), subretinal fluid (SRF), pigment epithelial detachment (PED), and central retinal thickness (CRT), evaluated at 6 months before switch (T1), at the time of switch (T2), and 3 months post-switch (T3).

Results

There was an increase in CRT from T1 to T2, which decreased after switch from T2 to T3. Regression analysis of the changes per month observed between time points showed significant differences in PED height (p = 0.02), SRF (p = 0.01), and neuroretinal thickness as a measure for IRF (p = 0.03). No significant change was found for VA. Predictive factors for better switch response included an exacerbation between T1 and T2, thicker measurements at T2, male sex, shorter treatment duration before switch, and fewer preceding injections. No association with preceding switch was found.

Conclusion

Patients with nAMD refractory to aflibercept benefit from switching to ranibizumab, particularly those whose condition worsened prior to the switch. This may be explained by drug tolerance to aflibercept. Our findings may facilitate making appropriate treatment decisions, potentially improving patient outcomes.

Prospective PED-study of intravitreal aflibercept for refractory vascularized pigment epithelium detachment due to age-related macular degeneration: morphologic characteristics of non-responders in optical coherence tomography

Purpose

The aim of this study was to investigate the outcomes of a fixed intravitreal aflibercept regimen in patients with vascular pigment epithelium detachment (vPED) secondary to age-related macular degeneration with refractory subretinal fluid.

Methods

A prospective, interventional case series involved 20 eyes of 20 patients with refractory subretinal fluid and vPED treated with at least three injections of intravitreal anti-VEGF prior to study inclusion. After study inclusion, patients were treated with three injections of intravitreal aflibercept 2 mg/0.05 mL monthly followed by injections every 8 weeks. Best-corrected visual acuity (BCVA) and spectral-domain optical coherence tomography (SD-OCT) were evaluated at all visits. Fluorescein angiography and indocyanine green angiography were performed at baseline and quarterly. Primary outcomes were effectivity of a fixed treatment as measured in change in BCVA, PED greatest linear diameter (GLD), and PED height from baseline to month 12. In an additional post hoc analysis, vPED patients were differentiated into two groups: (1) vPED lesions that showed persistence of subretinal fluid throughout 1 year of treatment and (2) vPED lesions that showed complete resolution of subretinal fluid at least at one of the monthly performed OCT volume scans. Reflectivity values were determined in the subretinal pigment epithelium (RPE) compartment in OCT scans at baseline, month 6 and 12.

Results

A total of 18 patients completed the study protocol. The mean age was 74.8 ± 10.6 years, and six patients were female. The median BCVA of all patients was 72.0 ± 8.0 EDTRS letters at baseline and 72.5 ± 9.5 EDTRS letters at 12-month follow-up (p = 0.7420). The median PED height in all patients as measured in the OCT images significantly decreased from 372.0 ± 140.0 μm to 149.0 ± 142.0 μm after 12 months of treatment (p = 0.0020). Persistent subretinal fluid was present at every OCT control in six patients (group 1). Twelve patients showed resolution of subretinal fluid at least at one OCT control (group 2). Reflectivity values in the sub-RPE compartment in OCT scans were 41.48 ± 4.48 (group 1) and 42.62 ± 12.34 (group 2) at baseline (p = 0.854) and 65.88 ± 6.74 and 50.87 ± 14.11 at month 12 (p = 0.038).

Conclusions

Intravitreal aflibercept in refractory vPED leads to a significant reduction in PED height and disease activity as well as preservation of BCVA over 1 year. Persistent subretinal fluid was present in PED lesions with high values of reflectivity under the RPE, suggesting both a diffusion barrier and an increasing fibrovascular maturization of the choroidal neovascularization.

Trial registration

ClinicalTrials.gov Identifier: NCT03370380

Efficacy of switching therapy to aflibercept for patients with persistent diabetic macular edema: a systematic review and meta-analysis

Background

To evaluate functional and anatomical consequences of switching anti-vascular endothelial growth factor (anti-VEGF) therapy from bevacizumab and/or ranibizumab to aflibercept intravitreal injection for the treatment of persistent diabetic macular edema (DME).

Methods

Analysis of switching treatment in patients with persistent DME was performed using a literature search across multiple databases (PubMed, Medline, EMBASE, Cochrane Library and Web of Science) prior to May 2019. Therapeutic effect parameters, including mean change of best-corrected visual acuity (BCVA) and central macular thickness (CMT), were extracted from baseline to different follow-up times post initial injections. The quality of studies was assessed with the Downs and Black checklist. Data pertaining to ocular and systemic safety adverse events (SAEs) were collected as well as subgroup analysis stratified by pre-switch anti-VEGF reagents. All results were analyzed and pooled using random-effects models with 95% confidence intervals (CI).

Results

Fourteen studies involving 489 eyes met the inclusion criteria. The mean differences in BCVA were significantly improved at 1, 2 and 3 months with −0.11 logMAR (P=0.016), −0.22 logMAR (P<0.001) and −0.24 logMAR (P<0.01), respectively. Vision gain was also assessed following the aflibercept injection with a mean change of −0.10 logMAR (P<0.001) at 6 months and −0.08 logMAR (P=0.01) at 12 months. CMT reduction was significant from baseline with a mean decrease of 80.52 µm (P<0.001) at 1 month, 89.6 µm (P<0.013) at 2 months, 113.88 µm (P<0.001) at 3 months and 125.12 µm (P<0.001) at 6 months. Mean CMT continued to decline by 75.70 µm (P<0.001) at 12 months as well.

Conclusions

This meta-analysis indicated the comparable efficacy and safety of a conversion treatment to aflibercept in cases of unsatisfactory responses to other anti-VEGF drugs. Switching treatment produces significant advantage for vision acuity recovery and macular edema improvement among persistent DME patients.

Simultaneous intravitreal dexamethasone and aflibercept for refractory macular edema secondary to retinal vein occlusion

PURPOSE

To assess the functional and anatomical outcomes of concurrent administration of aflibercept injection and dexamethasone (DEX) implant in patients with macular edema (ME) secondary to retinal vein occlusion (RVO), refractory to each of the two drugs previously administered as monotherapy. Secondary outcomes included the number of retreatments required in a 12-month follow-up and safety.

METHODS

This is a prospective, interventional case series of consecutive patients with refractory ME secondary to RVO, followed over a year. One injection of aflibercept was followed by a DEX implant on the same day; retreatment was driven by the persistence of ME on SD-OCT at least 4 months after the previous combined therapy. Central retinal thickness (CRT), best-corrected visual acuity (BCVA), and intraocular pressure (IOP) were collected at 1 month and then every 2 months until the end of follow-up.

RESULTS

Thirty eyes of 30 Caucasian patients were enrolled; mean duration of RVO before the first combined treatment was 25 ± 5 months (range 11 ± 30). Baseline BCVA was 0.73 ± 0.5 LogMAR, with no significant changes at 12 months (0.77 ± 0.51 μm, p = 0.2). Baseline CRT was 578.3 ± 161 μm, reducing to 352.5 ± 81 μm at 12 months (p = 0.003). Thirteen eyes (43.3%) required a second treatment. Twenty eyes (66.6%) showed no ME at the end of follow-up. One patient (3.3%) required topical IOP-lowering therapy during the study.

CONCLUSION

In eyes with ME secondary to RVO unresponsive to either aflibercept or DEX administered singularly, a combination therapy with simultaneous administration of aflibercept and DEX was effective in resolving ME, despite the absence of visual improvement. Earlier combined treatment in the course of the disease might lead to better functional outcomes.

Newly Identified Peptide, Peptide Lv, Promotes Pathological Angiogenesis

Background We recently discovered a small endogenous peptide, peptide Lv, with the ability to activate vascular endothelial growth factor receptor 2 and its downstream signaling. As vascular endothelial growth factor through vascular endothelial growth factor receptor 2 contributes to normal development, vasodilation, angiogenesis, and pathogenesis of various diseases, we investigated the role of peptide Lv in vasodilation and developmental and pathological angiogenesis in this study. Methods and Results The endothelial cell proliferation, migration, and 3-dimensional sprouting assays were used to test the abilities of peptide Lv in angiogenesis in vitro. The chick chorioallantoic membranes and early postnatal mice were used to examine its impact on developmental angiogenesis. The oxygen-induced retinopathy and laser-induced choroidal neovascularization mouse models were used for in vivo pathological angiogenesis. The isolated porcine retinal and coronary arterioles were used for vasodilation assays. Peptide Lv elicited angiogenesis in vitro and in vivo. Peptide Lv and vascular endothelial growth factor acted synergistically in promoting endothelial cell proliferation. Peptide Lv-elicited vasodilation was not completely dependent on nitric oxide, indicating that peptide Lv had vascular endothelial growth factor receptor 2/nitric oxide-independent targets. An antibody against peptide Lv, anti-Lv, dampened vascular endothelial growth factor-elicited endothelial proliferation and laser-induced vascular leakage and choroidal neovascularization. While the pathological angiogenesis in mouse eyes with oxygen-induced retinopathy was enhanced by exogenous peptide Lv, anti-Lv dampened this process. Furthermore, deletion of peptide Lv in mice significantly decreased pathological neovascularization compared with their wild-type littermates. Conclusions These results demonstrate that peptide Lv plays a significant role in pathological angiogenesis but may be less critical during development. Peptide Lv is involved in pathological angiogenesis through vascular endothelial growth factor receptor 2-dependent and -independent pathways. As anti-Lv dampened the pathological angiogenesis in the eye, anti-Lv may have a therapeutic potential to treat pathological angiogenesis.

Long-term outcomes of switching to aflibercept for treatment-resistant neovascular age-related macular degeneration

PURPOSE

To report 4-year outcomes following the switch to aflibercept in treatment-resistant neovascular age-related macular degeneration (nAMD).

METHODS

In this prospective, open-label, non-controlled, clinical trial, 49 patients with treatment-resistant nAMD received 2 mg intravitreal aflibercept as three loading doses every 4 weeks, followed by injections every 8 weeks for the first 48 weeks, then an individualized regimen for a further 36 months, following previous treatment with ranibizumab and/or bevacizumab. Outcome measures included best-corrected visual acuity (BCVA), central retinal thickness (CRT), pigment epithelial detachment (PED) height and geographic atrophy (GA) surface area.

RESULTS

Of the 49 patients who were initially recruited, data from 39 eyes of 39 patients were available at 48-month follow-up. Mean age was 76.7 ± 7.2 years. Over the 48 months, these eyes received a mean of 32.1 ± 5.6 injections. The mean BCVA improved significantly following 12 months of treatment (4.9 ± 9.0 ETDRS letters, p < 0.001); however, this was not maintained and was similar to baseline after 48 months (mean difference -0.4 ± 13.3 letters between baseline and 48 months, p < 0.001). The reduction in CRT from baseline was 170.3 ± 143.3 μm (p < 0.001) with absence of macular fluid in 56% of the 39 eyes at the end of month 48. PED height reduced by a mean 77.5 ± 20.0 μm, and geographic atrophy increased by a mean of 4.1 ± 3.4 mm² (p < 0.01) over the 48 months.

CONCLUSION

Aflibercept is an effective alternative therapy for treatment-resistant nAMD. Good anatomical and stable functional responses are achievable with continued therapy. The lack of continued visual improvement may be representative of GA progression, reflecting the progression of late-stage nAMD in these patients.

Switching to Aflibercept in Diabetic Macular Edema after Unsatisfactory Response to Other Anti-vascular Endothelial Growth Factor Drugs

PURPOSE

To evaluate the efficacy of switching to aflibercept in diabetic macular edema (DME) with suboptimal response to previous anti-vascular endothelial growth factor (anti-VEGF) injections.

METHODS

A prospective interventional case series study recruited patients from a single center diagnosed with DME with suboptimal response to anti-VEGF injections. Three consecutive monthly injections of aflibercept were performed. The primary outcome measure was mean change in visual acuity after switching to aflibercept.

RESULTS

Forty-two patients (42 eyes) were included. Baseline logarithm of the minimum angle of resolution (logMAR) visual acuity was 0.87 ± 0.23 and improved significantly to 0.62 ± 0.29, 0.56 ± 0.34, and 0.46 ± 0.35 at 1, 2, and 3 months, respectively, after the first injection. Mean baseline retinal thickness was 451.57 ± 107.09 μm and decreased significantly at 1, 2, and 3 months after switching to aflibercept (346.52 ± 79.03, 328.24 ± 81.98, and 313.71 ± 85.79 μm, respectively). Both visual improvement and mean change in retinal thickness were significant in patients with pre-aflibercept best-corrected visual acuity less than 1.0 logMAR but were not significant in patients with best-corrected visual acuity more than 1.0 logMAR.

CONCLUSIONS

Switching to aflibercept in DME patients with an unsatisfactory response to previous anti-VEGF injections provided acceptable short-term visual and retinal architectural improvement.

A meta-analysis of patients with treatment-resistant macular oedema secondary to retinal vein occlusions following switching to aflibercept

To systematically review anatomical and functional outcomes of switching therapy from bevacizumab and/or ranibizumab to aflibercept in patients with persistent macular oedema secondary to retinal vein occlusions (RVO). A systematic search of aflibercept for the treatment of persistent macular oedema secondary to branch and central RVO was performed in EMBASE, PubMed and Cochrane databases prior to June 2017. The main outcome variables described were best-corrected visual acuity (BCVA) and central macular thickness (CMT). All results were analysed and pooled using random-effects models with 95% confidence intervals (CI). Eight studies met the inclusion criteria with a total of 137 eyes, incorporating both branch and central RVO. Meta-analysis demonstrated a nonsignificant change in BCVA at 6 and 12 months following switch to aflibercept (4.40 letters, 95% CI: -3.10 to 11.90, p = 0.25 and 3.10 letters, 95% CI: -1.74 to 7.94, p = 0.21, respectively). Significant improvement in mean CMT was observed after switch to aflibercept at 6 (-256.00 μm, 95% CI: -318.00 to -194.00, p < 0.001) but not 12 months (-118.00 μm, 95% CI: -261.00 to 25.00, p = 0.11). Switching from bevacizumab/ranibizumab to aflibercept may improve persistent macular oedema secondary to RVO. However, there may be a limitation in the potential of visual recovery.

Real-World Results of Switching Treatment from Ranibizumab to Aflibercept in Macular Oedema Secondary to Branch Retinal Vein Occlusion

Introduction

To investigate treatment outcomes after switching from ranibizumab to aflibercept intravitreal injections in patients with macular oedema (MO) secondary to branch retinal vein occlusion (BRVO).

Methods

Eligible patients with refractory MO secondary to BRVO, post treatment with a minimum of three intravitreal injections of ranibizumab at 4-weekly intervals were recruited. Suboptimal or non-responders were defined as patients who had persistent intraretinal fluid (< 75% decrease from baseline) despite a minimum of three consecutive injections. These patients were switched to aflibercept injections on an as-needed basis. The primary study outcomes assessed trends in best-corrected distance visual acuity (BCVA) and central retinal thickness (CRT). To compare means of BCVA and CRT, a paired t test two-tailed with a level of significance set at 0.05 was used. Pearson correlation coefficient was also applied to demonstrate correlation. Participants were followed up for a period of 24 weeks after switching.

Results

Thirty-eight eyes of 38 patients were included in the study. Patients had an average of 8.37 ranibizumab intravitreal injections over a mean period of 12 months presenting suboptimal or no response. A significant decrease of mean CRT from 388.63 ± 93.4 μm to 290.29 ± 93.5 μm (p < 0.001) and an improvement in mean BCVA from logMAR 0.66 ± 0.38 to logMAR 0.57 ± 0.27 (p = 0.025) was achieved after an average of 2.27 aflibercept injections.

Conclusions

Given the spectrum of therapies available to date for the management of MO secondary to BRVO, aflibercept appears to be an effective treatment option in cases refractory to ranibizumab. This study based on a small cohort of patients indicates that satisfactory results on retinal anatomy and visual outcomes can be accomplished with a smaller number of injections. Larger-scale studies are needed to extrapolate these promising results.

"What should I inject next?" Challenging treatment decisions in the multiple anti-VEGF: a review of publications exploring anti-VEGF switching for nAMD

PURPOSE

The purpose of our work was to collate information from studies published to date focusing on switching in anti-VEGF therapy and describe the currently available data on anti-VEGF switching in nAMD.

METHODS

A PubMed search of published articles from January 2010 to January 2017 was conducted. Published studies were compared in parameters of sample size, reason for switch, duration of follow-up, and switch outcome (functional and anatomical).

RESULTS

Our search revealed 31 relevant publications. Switching from bevacizumab to ranibizumab mostly resulted in improvement in visual acuity (VA) and anatomical outcomes (CMT, CRT; 7/8 and 6/8 studies, respectively), whereas switching from ranibizumab to bevacizumab was less effective (no VA or anatomical improvement in 2/4 studies). Switching from either agent to aflibercept resulted mostly in improvement of anatomical outcomes (19/21 studies), but rarely in VA improvement (6/21 studies). Not all results were statistically significant, likely due to small sample sizes.

CONCLUSION

Switching anti-VEGF therapy from bevacizumab to ranibizumab might be of benefit (functionally and anatomically) for patients who failed to improve with intravitreal bevacizumab injections, whereas switching from either agent to aflibercept resulted mostly in reduced macular thickness only.

Neovascular age-related macular degeneration: intraocular inflammatory cytokines in the poor responder to ranibizumab treatment

Purpose

To determine the levels of interleukin (IL)-6, vascular endothelial growth factor-A, platelet-derived growth factor, placental growth factor (PLGF), and other cytokines in the aqueous fluid of patients with neovascular age-related macular degeneration who respond poorly to ranibizumab.

Patients and methods

This is an observational, prospective study. Thirty-two eyes from 30 patients were included in the study: 11 patients who responded poorly to ranibizumab and were switched to aflibercept (AF group), 8 patients who received ranibizumab and photodynamic therapy (PDT group), and 13 patients who responded to ranibizumab (control group). Aqueous fluid samples were collected for analysis of cytokine levels at baseline and after 1, 2, and 3 months of treatment. The effect of treatment on cytokine levels was compared between the study groups and between different time points using a linear mixed-effect regression model.

Results

In the AF group, there was an increase in vascular endothelial growth factor-C, IL-7, and angiopoeitin-2 levels (P=0.01) and a decrease in intercellular adhesion molecule and IL-17 levels (P=0.01) between baseline and 3 months. After adjustment for age, sex, race, and type of lesion at baseline, the PLGF level was higher (P=0.02) and the IL-7 level was lower (P=0.04) in the ranibizumab non-responder group than in the ranibizumab responder group.

Conclusion

Switching from ranibizumab to aflibercept did not reduce intraocular levels of angiogenesis cytokines, but resulted in improvement of central subfield thickness. PLGF levels were higher in poor responders to ranibizumab. The response of lesions to medication might be related to the stage of choroidal neovascularization.

Trial registration

www.ClinicalTrial.gov (NCT02218177c).