Systemic thromboembolic adverse events in patients treated with intravitreal anti-VEGF drugs for neovascular age-related macular degeneration: an overview

Evaluation of cardiac parameters and other safety outcomes of brolucizumab treatment in patients with neovascular age-related macular degeneration

This was a prospective, single‐dose, single‐arm, open‐label, non‐randomized, multicenter clinical study to determine cardiovascular safety after a single brolucizumab 6 mg intravitreal injection in neovascular age‐related macular degeneration patients (N = 14). Electrocardiogram (ECG) data were collected at different time points using 12‐lead Holter and standard ECG, and patients were followed up to 8 days (end of study) for any signs of ocular and non‐ocular adverse events (AEs). No clinically meaningful changes were observed in cardiac parameters. No patient had a ≥30 msec change from baseline in heart rate–corrected QT using Fridericia's formula (QTcF), and no patient had a new QTcF value of ≥450 msec between 20 and 24 h after treatment. No deaths or serious AEs were reported during the study period. These results are in line with the absence of new cardiovascular safety signal based on the ECG recordings collected over the first year of the pivotal studies performed with brolucizumab in DME.

Trial Registration: ClinicalTrials.gov identifier: NCT03954626.

Effect Modification by Indication to the Risks of Major Thromboembolic Adverse Events in Patients Receiving Intravitreal Anti-Vascular Endothelial Growth Factor Treatment: A Population-Based Retrospective Cohort Study

BACKGROUND

The association between intravitreal anti-vascular endothelial growth factor (anti-VEGF) treatment and the risk of major thromboembolic adverse events (TAEs) remains under debate. This study aimed to examine associated risks of TAEs in patients receiving intravitreal anti-VEGF treatment, and effect modification by different indications.

METHODS

This retrospective cohort study analyzed Taiwan's National Health Insurance Database during 2011-2017 to identify neovascular age-related macular degeneration (nAMD) or diabetic macular edema (DME) patients newly receiving intravitreal aflibercept or ranibizumab. We followed up patients for 2 years, or until the occurrence of TAEs, including ischemic heart disease, ischemic stroke, transient ischemic attack, deep vein thrombosis, and pulmonary embolism, death, or the end of the study period (i.e., 31 December 2018). We compared the risk of TAEs between patients with aflibercept and ranibizumab using Cox-proportional hazard models. We examined statistical interactions between the anti-VEGF treatment (i.e., ranibizumab and aflibercept) and indications (i.e., nAMD and DME) with regard to the outcome of TAEs.

RESULTS

We included 12,215 nAMD and 7532 DME patients. Among nAMD patients, those receiving aflibercept had lower risk of TAEs (adjusted hazard ratio [HR] 0.85; 95% CI 0.77-0.94) compared with those receiving ranibizumab. However, among DME patients, those receiving aflibercept had no differences in the risk of TAEs (1.14; 0.97-1.35) compared with those receiving ranibizumab. Among patients treated with ranibizumab, the DME group had a higher risk of TAEs than the nAMD group (HR 1.15; 95% CI 1.03-1.28); similar results were observed in patients treated with aflibercept (HR 1.53; 95% CI 1.27-1.85). When DME patients were treated with aflibercept, the risk of TAEs was 31% higher than when nAMD patients were treated with ranibizumab (HR 1.31; 95% CI 1.09-1.56; p < 0.05). The p-value for statistical interaction between the anti-VEGF treatment and indications was 0.0033.

CONCLUSIONS

Patients treated with aflibercept or ranibizumab for different indications may be associated with varying risk of TAEs. The findings provide evidence to support treatment selection, taking indications and TAE risk into consideration.

Impact of retinal vein occlusion on cardiovascular events in elderly Japanese patients

To assess the relationship between retinal vein occlusion (RVO) and the incidence of cardiovascular (CV) events.This was a single-institution, retrospective cohort study. We enrolled 57 patients diagnosed with RVO between January 2012 and December 2019, and 125 non-RVO patients who had undergone cataract surgery by a single surgeon between January and April 2012. We compared the relative risk and incidence rate ratio of CV events between the 2 groups. In addition, survival analysis was performed to calculate the hazard ratio (HR) using the Cox proportional hazards model. RVO, age, sex, blood pressure, body mass index, presence of diabetes, blood sample data, and smoking were considered confounders.The mean observation period (± standard deviation) for the RVO and non-RVO groups was 2.68 ± 2.04 and 2.81 ± 2.70 years, respectively. Seven CV events were observed in the RVO group and 2 in the non-RVO group. Relative risk and incidence rate ratio were 7.68 (95% confidence interval [CI]: 1.65-35.8) and 8.07 (95% CI: 1.54-79.6), respectively. Multivariate analysis revealed that the RVO group had a high HR for CV events (HR: 16.13 [95% CI: 2.29-113.74]) and older age (HR: 1.26 [95% CI: 1.06-1.49]).RVO can predict future CV events, especially in the elderly population. Fundus observations should be shared between ophthalmologists and internists to prevent future CV events.

Efficacy of Modified Treat-and-Extend Aflibercept Regimen for Macular Edema Due to Branch Retinal Vein Occlusion: 1-Year Prospective Study

PURPOSE

To assess the efficacy and safety of a modified treat-and-extend (mTAE) regimen of aflibercept for macular edema (ME) due to branch retinal vein occlusion (BRVO).

METHODS

This prospective multicentre intervention study evaluated 50 eyes of 50 patients enrolled from October 2016 to September 2017. The patients received intravitreal aflibercept (IVA) injections on an mTAE regimen for a total of 12 months. The main outcome measures were best-corrected visual acuity (BCVA) and central subfield thickness (CST) at 12 months.

RESULTS

The baseline BCVA and CST were 0.33 (0.27) and 488 (171) µm (mean (standard deviation)), respectively. The BCVA and CST were significantly improved at month 12 (0.067 (0.19) LogMAR and 295 (110) µm; both p < 0.0001, paired t-test). The mean number of clinic visits and IVA injections was 6.71 (1.41) and 4.26 (0.71), respectively. The time to first recurrence from the first injection was most frequently 3 months.

CONCLUSION

The mTAE regimen of IVA injections for ME due to BRVO effectively improved BCVA and reduced CST, and thus might be an effective therapy to reduce the number of injections and visits.

Effect of intravitreal injection of aflibercept on blood coagulation parameters in patients with age-related macular degeneration

Purpose:

Treatment with intravitreal injections of anti-vascular endothelial growth factor agents has been associated with an increased risk of arterial thromboembolic events. The aim of the present pilot study was to assess the effect of a single intravitreal injection of aflibercept on coagulation.

Methods:

Treatment-naïve patients with age-related macular degeneration (n = 47), who were scheduled to undergo treatment with intravitreal injections of aflibercept, were enrolled. None of the included patients received any anticoagulation therapy or had a history of a recent arterial thromboembolic event. Blood samples were collected before the first intravitreal injection, and at 7 and 30 days after aflibercept administration. We evaluated coagulation parameters, such as platelet count and plasma fibrinogen and D-dimer levels; functional clotting parameters, such as prothrombin time, international normalized ratio, and activated partial thromboplastin time; and anticoagulant parameters, such as the levels of Proteins S and C.

Results:

The levels of all of the evaluated biomarkers were within the normal range at baseline and at both the time points throughout the study. No statistically significant changes were observed in any of the measured parameters at 1 week and 1 month after aflibercept administration.

Conclusion:

A single intravitreal injection of aflibercept in treatment-naïve patients with exudative age-related macular degeneration has no statistically significant effect on blood coagulation parameters for up to 1 month after aflibercept administration. Our results also provide an explorative statistical data, and further studies are required to evaluate any significant clinical effects of aflibercept on blood coagulation parameters.

ClinicalTrials.gov ID:

NCT03509623.

Intraocular Penetration of a vNAR: In Vivo and In Vitro VEGF165 Neutralization

Variable new antigen receptor domain (vNAR) antibodies are novel, naturally occurring antibodies that can be isolated from naïve, immune or synthetic shark libraries. These molecules are very interesting to the biotechnology and pharmaceutical industries because of their unique characteristics related to size and tissue penetrability. There have been some approved anti-angiogenic therapies for ophthalmic conditions, not related to vNAR. This includes biologics and chimeric proteins that neutralize vascular endothelial growth factor (VEGF)₁₆₅, which are injected intravitreal, causing discomfort and increasing the possibility of infection. In this paper, we present a vNAR antibody against human recombinant VEGF₁₆₅ (rhVEGF₁₆₅) that was isolated from an immunized Heterodontus francisci shark. A vNAR called V13, neutralizes VEGF₁₆₅ cytokine starting at 75 μg/mL in an in vitro assay based on co-culture of normal human dermal fibroblasts (NHDFs) and green fluorescence protein (GFP)-labeled human umbilical vein endothelial cells (HUVECs) cells. In the oxygen-induced retinopathy model in C57BL/6:Hsd mice, we demonstrate an endothelial cell count decrease. Further, we demonstrate the intraocular penetration after topical administration of 0.1 μg/mL of vNAR V13 by its detection in aqueous humor in New Zealand rabbits with healthy eyes after 3 h of application. These findings demonstrate the potential of topical application of vNAR V13 as a possible new drug candidate for vascular eye diseases.

Intravitreal Bevacizumab and Cardiovascular Risk in Patients with Age-Related Macular Degeneration: Systematic Review and Meta-Analysis of Randomized Controlled Trials and Observational Studies

INTRODUCTION

Intravitreal bevacizumab (IVTB) is used to treat age-related macular degeneration (ARMD), although its use is off-label and its cardiovascular safety has not been unequivocally established.

OBJECTIVES

Our objective was to assess the cardiovascular safety of IVTB in patients with ARMD.

METHODS

We conducted a systematic review and meta-analysis of published randomized controlled trials (RCTs) and observational studies.

RESULTS

Of the 2028 non-duplicate records, five RCTs versus ranibizumab (N = 3038, 12/24 months), four RCTs comparing different regimens (N = 809, 12/23 months), one RCT versus pegaptanib, photodynamic therapy (PDT), or sham (N = 131, 12 months), and three observational studies versus PDT, ranibizumab, or pegaptanib (~150,000 or 1666 patients/12 months and 317 patients/1-2 years, respectively) had a low risk of bias/high quality and ≥20 patients per arm with ≥6 months and ≥3 injections of treatment. RCT-based comparisons with PDT or pegaptanib are negligible. Observational data have not demonstrated differences [all-cause mortality, myocardial infarction (MI), stroke], but the level of evidence is "very low" (imprecise, indirect). RCT-based comparisons with ranibizumab did not demonstrate differences regarding some outcomes, although certain point estimates were at the level of a relevant harm/benefit [all-cause mortality odds ratio (OR) 1.103, 95 % confidence interval (CI) 0.641-1.898; vascular mortality OR 1.380, 95 % CI 0.476-3.997; MI OR 0.551, 95 % CI 0.265-1.146; stroke OR 0.657, 95 % CI 0.260-1.660; transitory ischemic attack OR 1.536, 95 % CI 0.444-5.313; atherothrombotic events (ATEs) OR 1.007, 95 % CI 0.641-1.593; venous thromboembolism OR 2.325, 95 % CI 0.963-5.612] or suggested a higher risk with bevacizumab (hypertension OR 7.512, 95 % CI 1.056-52.3), but estimates were based on sparse data, were extremely imprecise, and commonly exhibited considerable heterogeneity/inconsistency. The level of evidence per outcome was "low" or "very low". Observational data did not demonstrate difference (all-cause mortality, MI, stroke), or suggested a higher risk with bevacizumab (ATE), but were imprecise and indirect (level of evidence "very low"). RCT-based comparisons of different IVTB regimens suffered from the same limitations.

CONCLUSION

Published data on IVTB in AMRD provide only a low level of evidence on its cardiovascular safety and do not support any finite conclusions.

SAVE-AMD: Safety of VEGF Inhibitors in Age-Related Macular Degeneration

OBJECTIVE

To determine whether intraocular treatment with vascular endothelial growth factor (VEGF) inhibitors change systemic endothelial function (EF) in patients with neovascular age-related macular degeneration (AMD).

METHODS

In this prospective, randomized, 2-center, double-masked controlled interventional trial, patients with neovascular and dry AMD were enrolled. Eligible neovascular AMD patients received 2 intravitreal loading doses of either ranibizumab 0.5 mg or bevacizumab 1.25 mg at 4-week intervals and were subsequently followed every 4 weeks and treated according to a pro re nata regime for up to 1 year. Patients with dry AMD served as controls. The primary endpoint was the change in EF assessed by flow-mediated dilatation (FMD) after 2 months of treatment with VEGF inhibitors in patients with AMD compared to patients with dry AMD. FMD was assessed with B-mode high-resolution ultrasonography of the left brachial artery.

RESULTS

24 patients with neovascular AMD and 26 patients with dry ADM were included in the trial. Treatment with VEGF inhibitors did not significantly change FMD (from 4.7 ± 2.4 to 3.9 ± 1.9% after 8 weeks, p = 0.07, and to 5.1 ± 2.0% after 1 year; p = 0.93 vs. baseline, respectively).

CONCLUSIONS

EF did not significantly differ between patients with neovascular AMD treated with intravitreal VEGF inhibition and patients with dry AMD.

Long Term Glaucoma Drug Delivery Using a Topically Retained Gel/Microsphere Eye Drop

The purpose of this study was to characterize and determine the efficacy of a long-term, non-invasive gel/microsphere (GMS) eye drop for glaucoma. This novel drug delivery system is comprised of a thermoresponsive hydrogel carrier and drug-loaded polymer microspheres. In vitro release of brimonidine from the GMS drops and gel properties were quantified. A single brimonidine-loaded GMS drop was administered to 5 normotensive rabbits and intraocular pressure (IOP) was monitored for 28 days. Here we report that IOP reduction in rabbits receiving a single brimonidine GMS drop was comparable to that of rabbits receiving twice daily, standard brimonidine drops. GMS drops were retained in the inferior fornix in all animals for the length of the study. Our results suggest in vivo efficacy over 28 days from a single GMS drop and a potential decrease in systemic absorption, based on a lack of substantial IOP effects on the fellow untreated eye, compared to brimonidine twice-daily eye drops. To our knowledge, this represents the first long-term, drug-releasing depot that can be administered as a traditional eye drop.

BMP9/ALK1 inhibits neovascularization in mouse models of age-related macular degeneration

Age-related macular degeneration (AMD) is the leading cause of blindness in aging populations of industrialized countries. The drawbacks of inhibitors of vascular endothelial growth factor (VEGFs) currently used for the treatment of AMD, which include resistance and potential serious side-effects, require the identification of new therapeutic targets to modulate angiogenesis. BMP9 signaling through the endothelial Alk1 serine-threonine kinase receptor modulates the response of endothelial cells to VEGF and promotes vessel quiescence and maturation during development. Here, we show that BMP9/Alk1 signaling inhibits neovessel formation in mouse models of pathological ocular angiogenesis relevant to AMD. Activating Alk1 signaling in laser-induced choroidal neovascularization (CNV) and oxygen-induced retinopathy (OIR) inhibited neovascularization and reduced the volume of vascular lesions. Alk1 signaling was also found to interfere with VEGF signaling in endothelial cells whereas BMP9 potentiated the inhibitory effects of VEGFR2 signaling blockade, both in OIR and laser-induced CNV. Together, our data show that targeting BMP9/Alk1 efficiently prevents the growth of neovessels in AMD models and introduce a new approach to improve conventional anti-VEGF therapies.

Introducing Anti-Vascular Endothelial Growth Factor Therapies for AMD Did Not Raise Risk of Myocardial Infarction, Stroke, and Death

PURPOSE

To assess the effect of availability of anti-vascular endothelial growth factor (VEGF) therapy on mortality and hospitalizations for acute myocardial infarction (AMI) and stroke over a 5-year follow-up period in United States Medicare beneficiaries newly diagnosed with exudative age-related macular degeneration (AMD) in 2006 compared with control groups consisting of beneficiaries (1) newly diagnosed with exudative AMD at a time when anti-VEGF therapy was not possible and (2) newly diagnosed with nonexudative AMD.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Beneficiaries newly diagnosed with exudative and nonexudative AMD in 2000 and 2006 selected from a random longitudinal sample of Medicare 5% claims and enrollment files.

METHODS

Beneficiaries with a first diagnosis of exudative AMD in 2006 were the treatment group; beneficiaries newly diagnosed with exudative AMD in 2000 or nonexudative AMD in 2000 or 2006 were control groups. To deal with potential selection bias, we designed an intent-to-treat study, which controlled for nonadherence to prescribed regimens. The treatment group consisted of patients with clinically appropriate characteristics to receive anti-VEGF injections given that the therapy is available, bypassing the need to monitor whether treatment was actually received. Control groups consisted of patients with clinically appropriate characteristics but first diagnosed at a time when the therapy was unavailable (2000) and similar patients but for whom the therapy was not clinically indicated (2000, 2006). We used a Cox proportional hazard model.

MAIN OUTCOME MEASURES

All-cause mortality and hospitalization for AMI and stroke during follow-up.

RESULTS

No statistically significant changes in probabilities of death and hospitalizations for AMI and stroke within a 5-year follow-up period were identified in exudative AMD beneficiaries newly diagnosed in 2006, the beginning of widespread anti-VEGF use, compared with 2000. As an alternative to our main analysis, which excluded beneficiaries from nonexudative AMD group who received anti-VEGF therapies during follow-up, we performed a sensitivity analysis with this group of individuals reincluded (11% of beneficiaries newly diagnosed with nonexudative AMD in 2006). Results were similar.

CONCLUSIONS

Introduction of anti-VEGF agents in 2006 for treating exudative AMD has not posed a threat of increased risk of AMI, stroke, or all-cause mortality.

Aflibercept: a review of its use in the treatment of choroidal neovascularization due to age-related macular degeneration

Choroidal neovascularization (CNV) due to age-related macular degeneration (AMD) is an important cause of visual morbidity globally. Modern treatment strategies for neovascular AMD achieve regression of CNV by suppressing the activity of key growth factors that mediate angiogenesis. Vascular endothelial growth factor (VEGF) has been the major target of neovascular AMD therapy for almost two decades, and there have been several intravitreally-administered agents that have enabled anatomical restitution and improvement in visual function with continual dosing. Aflibercept (EYLEA(®)), initially named VEGF Trap-eye, is the most recent anti-VEGF agent to be granted US Food and Drug Administration approval for the treatment of neovascular AMD. Biologic advantages of aflibercept include its greater binding affinity for VEGF, a longer intravitreal half-life relative to other anti-VEGF agents, and the capacity to antagonize growth factors other than VEGF. This paper provides an up-to-date summary of the molecular mechanisms mediating CNV. The structural, pharmacodynamic, and pharmacokinetic advantages of aflibercept are also reviewed to rationalize the utility of this agent for treating CNV. Results of landmark clinical investigations, including VIEW 1 and 2 trials, and other important studies are then summarized and used to illustrate the efficacy of aflibercept for managing treatment-naïve CNV, recalcitrant CNV, and CNV due to polypoidal choroidal vasculopathy. Safety profile, patient tolerability, and quality of life measures related to aflibercept are also provided. The evidence provided in this paper suggests aflibercept to be a promising agent that can be used to reduce the treatment burden of neovascular AMD.

Fellow Eye Macular Edema Improvement after Intravitreal Bevacizumab for Radiation Retinopathy

Radiation retinopathy (RR) is a progressive, chronic condition directly related to the amount of radiation administered to the retina. We report a 37-year-old patient with medulloblastoma that was treated with external beam radiation and presented to us with bilateral cystoid macular edema. He was treated with monthly bevacizumab injections only in his worst seeing eye. There was a significant improvement in his fellow eye, with marked retinal thickness reduction. Therefore, we present clinical evidence of systemic absorption and fellow eye activity of the drug (bevacizumab). One must be aware of distant side effects after intravitreal injections.

Comparison of single injection and three monthly injections of intravitreal bevacizumab for macular edema associated with branch retinal vein occlusion

Purpose

Our aim was to compare the 1 year efficacy and safety results of intravitreal bevacizumab (IVB) in two prospective, consecutive groups of patients with macular edema (ME) following branch retinal vein occlusion (BRVO).

Patients and methods

Twenty-five eyes with ME after BRVO received one IVB injection (single-injection group) and 27 eyes received three monthly IVB injections (three-injection group). Both groups were followed monthly for 12 months. The best-corrected visual acuity (BCVA) and the central foveal thickness (CFT) on optical coherence tomography were evaluated before and after treatment. Patients were eligible to receive an IVB injection if the mean CFT increased 100 μm or more or the BCVA decreased 0.1 logarithm of the minimum angle of resolution (logMAR) unit or more compared with values measured on the last visit.

Results

The mean logMAR BCVA and CFT, respectively, improved from 0.56 to 0.33 and from 598 μm to 348 μm in the single-injection group (P<0.001) and from 0.55 to 0.26 and from 514 μm to 293 μm in the three-injection group (P<0.001). During the study period, the mean total number of injections was significantly smaller in the single-injection group than in the three-injection group (2.1 and 4.3, respectively, P<0.001). No serious complications related to the IVB injections developed in either group.

Conclusion

The single-injection group achieved similar visual outcomes for ME secondary to BRVO with fewer injections compared with the three-injection group.

17β-estradiol ameliorates light-induced retinal damage in Sprague-Dawley rats by reducing oxidative stress

Oxidative stress is considered as a major cause of light-induced retinal neurodegeneration. The protective role of 17β-estradiol (βE2) in neurodegenerative disorders is well known, but its underlying mechanism remains unclear. Here, we utilized a light-induced retinal damage model to explore the mechanism by which βE2 exerts its neuroprotective effect. Adult male and female ovariectomized (OVX) rats were exposed to 8,000 lx white light for 12 h to induce retinal light damage. Electroretinogram (ERG) assays and hematoxylin and eosin (H&E) staining revealed that exposure to light for 12 h resulted in functional damage to the rat retina, histological changes, and retinal neuron loss. However, intravitreal injection (IVI) of βE2 significantly rescued this impaired retinal function in both female and male rats. Based on the level of malondialdehyde (MDA) production (a biomarker of oxidative stress), an increase in retinal oxidative stress followed light exposure, and βE2 administration reduced this light-induced oxidative stress. Quantitative reverse-transcriptase (qRT)-PCR indicated that the messenger RNA (mRNA) levels of the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (Gpx) were downregulated in female OVX rats but were upregulated in male rats after light exposure, suggesting a gender difference in the regulation of these antioxidant enzyme genes in response to light. However, βE2 administration restored or enhanced the SOD and Gpx expression levels following light exposure. Although the catalase (CAT) expression level was insensitive to light stimulation, βE2 also increased the CAT gene expression level in both female OVX and male rats. Further examination indicated that the antioxidant proteins thioredoxin (Trx) and nuclear factor erythroid 2-related factor 2 (Nrf2) are also involved in βE2-mediated antioxidation and that the cytoprotective protein heme oxygenase-1 (HO-1) plays a key role in the endogenous defense mechanism against light exposure in a βE2-independent manner. Taken together, we provide evidence that βE2 protects against light-induced retinal damage via its antioxidative effect, and its underlying mechanism involves the regulation of the gene expression levels of antioxidant enzymes (SOD, CAT, and Gpx) and proteins (Trx and Nrf2). Our study provides conceptual evidence in support of estrogen replacement therapy for postmenopausal women to reduce the risk of age-related macular degeneration.

Choosing preclinical study models of diabetic retinopathy: key problems for consideration

Diabetic retinopathy (DR) is the most common complication of diabetes mellitus in the eye. Although the clinical treatment for DR has already developed to a relative high level, there are still many urgent problems that need to be investigated in clinical and basic science. Currently, many in vivo animal models and in vitro culture systems have been applied to solve these problems. Many approaches have also been used to establish different DR models. However, till now, there has not been a single study model that can clearly and exactly mimic the developmental process of the human DR. Choosing the suitable model is important, not only for achieving our research goals smoothly, but also, to better match with different experimental proposals in the study. In this review, key problems for consideration in choosing study models of DR are discussed. These problems relate to clinical relevance, different approaches for establishing models, and choice of different species of animals as well as of the specific in vitro culture systems. Attending to these considerations will deepen the understanding on current study models and optimize the experimental design for the final goal of preventing DR.

Identification of chemokines and growth factors in proliferative diabetic retinopathy vitreous

Associations were investigated between levels of chemokines and growth factors in the vitreous and proliferative diabetic retinopathy (PDR). Enrolled were 58 patients (58 eyes) requiring pars plana vitrectomy (PPV), with PDR (n=32, none with traction retinal detachment) or not (non-PDR). In the latter, 16 had macular hole (MH) and 10 had epiretinal membrane (ERM). With a multiplex bead immunoassay, levels of 11 chemokines and growth factors were measured from the undiluted vitreous sample from each patient. In the non-PDR eyes, the levels of the 11 chemokines and growth factors tested were similar between patients with MH and those with ERM. However, the levels of all 11 were significantly higher in the PDR eyes relative to the non-PDR; CCL17, CCL19, and TGFβ3 were markedly upregulated and have not been investigated in PDR previously. The significantly higher levels of CCL4 and CCL11 in PDR contradict the results of previous reports. Based on Spearman's nonparametric test, moderate-to-strong correlations were found between VEGF and other mediators. Our results indicate that these chemokines and growth factors could be candidates for research into targeted therapies applied either singly or in combination with anti-VEGF drugs for the treatment of PDR.