Aflibercept, bevacizumab or ranibizumab for diabetic macular oedema: recent clinically relevant findings from DRCR.net Protocol T

Diabetic retinopathy: A review on its pathophysiology and novel treatment modalities

Diabetes mellitus (DM) is a chronic metabolic non-communicable disease with the ability to cause serious microvascular and macrovascular complications throughout the body, including in the eye. Diabetic retinopathy (DR), present in one-third of patients with diabetes, is a vision-threatening complication caused by uncontrolled diabetes, which greatly affects the retinal blood vessels and the light-sensitive inner retina, eventually leading to blindness. Several epidemiological studies elucidate that DR can vary by age of onset, duration, types of diabetes, and ethnicity. Recent studies show that the pathogenesis of diabetic retinopathy has spread its roots beyond merely being the result of hyperglycemia. The complexity of its etiopathology and diagnosis makes therapeutic intervention challenging. This review throws light on the pathological processes behind DR, the cascade of events that follow it, as well as the available and emerging treatment options.

Diabetic retinopathy: New concepts of screening, monitoring, and interventions

The science of diabetes care has progressed to provide a better understanding of the oxidative and inflammatory lesions and pathophysiology of the neurovascular unit within the retina (and brain) that occur early in diabetes, even prediabetes. Screening for retinal structural abnormalities, has traditionally been performed by fundus examination or color fundus photography; however, these imaging techniques detect the disease only when there are sufficient lesions, predominantly hemorrhagic, that are recognized to occur late in the disease process after significant neuronal apoptosis and atrophy, as well as microvascular occlusion with alterations in vision. Thus, interventions have been primarily oriented toward the later-detected stages, and clinical trials, while demonstrating a slowing of the disease progression, demonstrate minimal visual improvement and modest reduction in the continued loss over prolonged periods. Similarly, vision measurement utilizing charts detects only problems of visual function late, as the process begins most often parafoveally with increasing number and progressive expansion, including into the fovea. While visual acuity has long been used to define endpoints of visual function for such trials, current methods reviewed herein are found to be imprecise. We review improved methods of testing visual function and newer imaging techniques with the recommendation that these must be utilized to discover and evaluate the injury earlier in the disease process, even in the prediabetic state. This would allow earlier therapy with ocular as well as systemic pharmacologic treatments that lower the and neuro-inflammatory processes within eye and brain. This also may include newer, micropulsed laser therapy that, if applied during the earlier cascade, should result in improved and often normalized retinal function without the adverse treatment effects of standard photocoagulation therapy.

The effect of intravitreal anti-VEGF injections on choroidal vascular index in patients with diabetic macular edema

PURPOSE

This study aims to examine and compare the effects of intravitreal bevacizumab injection (IVB) at subfoveal 1500 micron (μm) and submacular 6000 μm in patients with diabetic macular edema (DME).

METHODS

Fifty eyes of 45 patients with DME who completed six doses of IVB were included in the study group, and 50 eyes of 42 patients who had diabetic retinopathy (DR) but did not receive any treatment were included in the control group. Central macular thickness (CMT), central choroidal thickness (CCT), subfoveal and total choroidal area (TCA), and choroidal vascular index (CVI) were calculated and their changes at zero, three and six months were evaluated.

RESULTS

At baseline, CVI was significantly lower in both the subfoveal and total macular areas in the study group (p = 0.004, p = 0.003). In the study group, a significant decrease was observed in CVI between zero and six months in the subfoveal area (p = 0.001). In the submacular area, the decrease in CVI in the study group was significant between zero to three months and zero to six months. There was moderate correlation between measurements of CVI in the subfoveal and total macular areas (r = 0.66, p < 0.001).

CONCLUSION

These findings indicate that intravitreal bevacizumab injection reduces the CVI and the effects of intravitreal anti-VEGF on CVI emerge earlier and more prominently in the submacular 6000 µm area.

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

PURPOSE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSION

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

Efficacy of anti-VEGF monotherapy versus anti-VEGF therapy with subthreshold micropulse laser (SML) in the management of diabetic macular oedema (DMO): a systematic review and meta-analysis

BACKGROUND

Intravitreal injection anti-vascular endothelial growth factor (IVI anti-VEGF) therapy serves as the primary treatment for centre involving diabetic macular oedema (DMO). Conventional laser therapy (CLT) adjunct has proven beneficial; however, it is not widely used due to significant risks of retinal scarring. Subthreshold micropulse laser (SML) therapy has, however, emerged as a comparable alternative to combination therapy, offering a distinct advantage by mitigating the risk of retinal scarring.

METHODS

A search of six databases was conducted. A meta-analysis of mean differences was performed including subgroup analyses where appropriate. Primary outcome was the number of injections at 12-14 months; secondary outcomes were changes in central macular thickness (CMT) and best corrected visual acuity (BCVA) at 6-8 months and 12-14 months.

RESULTS

A total of ten papers including six randomised clinical trials and four retrospective clinical studies were included in our study, capturing 563 eyes of 478 patients. Overall, the risk of bias was moderate for these studies. Significantly fewer anti-VEGF therapy injections were administered in the combination therapy versus anti-VEGF monotherapy patients at 12-14 months who had poor visual acuity (6/18 Snellen or worse) at baseline, mean difference - 2.25 (95% CI; - 3.35, - 1.15; p < 0.05). Combination therapy was not associated with significantly fewer intravitreal injections in patients with a higher visual acuity (6/15 Snellen or better) at baseline. Our analysis also showed significant improvements to both BCVA and CMT were reached at 6 - 8 month post-baseline at the 95% confidence intervals: - 1.13 (- 2.09, - 0.16) and - 4.04 (- 7.59, - 0.50). These improvements remained statistically significant at 12-14 months: - 0.94 (- 1.67, - 0.20) and - 1.92 (- 3.52, - 0.32) respectively with combination therapy.

CONCLUSION

Our findings demonstrate that combination therapy (SML + IVI anti-VEGF) is associated with fewer intravitreal injections. We report a better BCVA and a reduction in CMT at 6 and 12 months from baseline with combination treatment compared to the IVI anti-VEGF monotherapy comparator. SML is a proven non-scarring cost-effective therapy for DMO that should be readily available in the medical retinal therapy as it may reduce the burden of care.

Aflibercept vs. dexamethasone implant for recalcitrant diabetic macular edema in pseudophakic eyes - 1-year outcomes from a quazi-randomized study in India

PURPOSE

To assess the safety and efficacy of intravitreal Aflibercept (IVA) versus dexamethasone (DEX) implant for treating recalcitrant diabetic macular edema (DME) in pseudophakic eyes at 1-year follow-up.

DESIGN

Retrospective comparative case series.

PARTICIPANTS

Data of all patients diagnosed with DME between January 2019 and December 2021, who underwent 4-monthly doses of intravitreal ranibizumab but had persistent DME [central macular thickness (CMT) within 10% of baseline value] were extracted from a computerized database. Of these, only pseudophakic eyes that underwent either IVA or DEX implant and had at least 1-year follow-up were included for analysis.

METHODS

DEX implant was preferred before December 2020 and IVA after this time point. In the IVA group, patients were followed up every month while DEX were followed at least every 3 months. Reinjections were considered when vision dropped by at least 1 Snellen's line or CMT increased by at least 10% from the previous visit in both groups.

MAIN OUTCOME MEASURES

Comparison of change in vision and CMT at 1-year follow-up in DEX versus IVA groups.

RESULTS

Eighty-four eyes of 84 patients aged 54.4 + 4.4 years were included, 39 (46%) received DEX and 45 (54%) received IVA. Groups were comparable for baseline vision and CMT. Vision improved equally in both groups from 0.83 + 0.15 logMAR to 0.52 + 0.10 logMAR at 3 months ( P < 0.01) and then stabilized till 1 year. However, eyes in the IVA group were 6.5 times more likely (Odds ratio = 6.45, 95% CI = 1.3 - 31.9) to achieve >3-line improvement in vision. The CMT reduction was also comparable between groups (-169 + 51 in DEX vs. -174 + 49 in IVA, P = 0.67). More eyes in the IVA group required >3 injections (91% vs. 69% in DEX, P = 0.01). The IOP was significantly higher at 6 and 9 months in the DEX group and 5 eyes (13%) required IOP lowering medications.

CONCLUSION

In pseudophakic eyes with recalcitrant DME not responding to ranibizumab, switching to IVA or DEX implant results in equal visual improvement and CMT reduction. Though >3-line improvement occurs more frequently with IVA, this comes at the expense of a greater number of injections and follow-up visits.

Vascular Endothelial Growth Factor C and D Signaling Pathways as Potential Targets for the Treatment of Neovascular Age-Related Macular Degeneration: A Narrative Review

The development of treatments targeting the vascular endothelial growth factor (VEGF) signaling pathways have traditionally been firstly investigated in oncology and then advanced into retinal disease indications. Members of the VEGF family of endogenous ligands and their respective receptors play a central role in vasculogenesis and angiogenesis during both development and physiological homeostasis. They can also play a pathogenic role in cancer and retinal diseases. Therapeutic approaches have mostly focused on targeting VEGF-A signaling; however, research has shown that VEGF-C and VEGF-D signaling pathways are also important to the disease pathogenesis of tumors and retinal diseases. This review highlights the important therapeutic advances and the remaining unmet need for improved therapies targeting additional mechanisms beyond VEGF-A. Additionally, it provides an overview of alternative VEGF-C and VEGF-D signaling involvement in both health and disease, highlighting their key contributions in the multifactorial pathophysiology of retinal disease including neovascular age-related macular degeneration (nAMD). Strategies for targeting VEGF-C/-D signaling pathways will also be reviewed, with an emphasis on agents currently being developed for the treatment of nAMD.

Efficacy of Faricimab versus Aflibercept in Diabetic Macular Edema in the 20/50 or Worse Vision Subgroup in Phase III YOSEMITE and RHINE Trials

PURPOSE

Diabetic Retinopathy Clinical Research Network Protocol T suggests that the response to treatment among patients with diabetic macular edema (DME) may vary depending on baseline best-corrected visual acuity (BCVA). We evaluated the efficacy of faricimab 6 mg versus aflibercept 2 mg over 2 years in patients with DME and baseline BCVA of 20/50 or worse enrolled in faricimab phase III trials.

DESIGN

YOSEMITE and RHINE were identically designed, multicenter, randomized, double-masked, active comparator-controlled, noninferiority trials.

PARTICIPANTS

Adults ≥18 years of age with center-involving macular edema secondary to type 1 or 2 diabetes.

METHODS

Patients were randomized to faricimab every 8 weeks (Q8W), faricimab personalized treat-and-extend (T&E) regimen, or aflibercept Q8W. Post hoc subgroup analyses were conducted using the intention-to-treat population with baseline BCVA of 20/50 or worse.

MAIN OUTCOME MEASURES

Changes in ETDRS BCVA and central subfield thickness (CST) from baseline to years 1 and 2 were compared between treatment arms using mixed-model repeated measures analyses.

RESULTS

In YOSEMITE and RHINE, respectively, 220 and 217 patients in the faricimab Q8W arm, 220 and 219 patients in the faricimab T&E arm, and 219 and 214 patients in the aflibercept Q8W arm showed baseline BCVA of 20/50 or worse. In both trials, mean change in ETDRS BCVA was comparable between treatments across trials at years 1 and 2. In YOSEMITE, adjusted mean change from baseline in CST (μm) at year 1 was greater with faricimab Q8W (-232.8; P < 0.0001) and faricimab T&E (-217.4; P = 0.0004) ) versus aflibercept Q8W (-190.4). In RHINE, this was faricimab Q8W (-214.2; P = 0.0006) and faricimab T&E (-206.6; P = 0.0116) versus aflibercept Q8W (-186.6). In both trials, change from baseline in CST at year 2 was greater with faricimab Q8W versus aflibercept. The median time to first CST of <325 μm and first absence of intraretinal fluid was shorter in the faricimab arms versus the aflibercept arm, with fewer injections on average.

CONCLUSIONS

In patients with DME and baseline ETDRS BCVA of 20/50 or worse, faricimab treatment resulted in comparable visual acuity, greater reduction in retinal thickness, and fewer injections compared with aflibercept.

FINANCIAL DISCLOSURE(S)

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

Switching to an Intravitreal Dexamethasone Implant after Intravitreal Anti-VEGF Therapy for Diabetic Macular Edema: A Review

Among working-age people, diabetic retinopathy and diabetic macular edema are currently considered the main causes of blindness. Nowadays, intravitreal injections are widely acknowledged as a significant milestone in ophthalmology, especially for the treatment of several retinal diseases, including diabetic macular edema. In particular, anti-vascular endothelial growth factor (VEGF) agents are typically the first line of treatment; however, monthly injections are required, at least, during the loading dosage. Notably, an intravitreal 0.7 mg dexamethasone (DEX) implant (Ozurdex®, AbbVie Inc., North Chicago, IL, USA) is considered a legitimate substitute treatment for diabetic eyes that have not responded to anti-VEGF treatment. In fact, clinical trials and real-life studies have demonstrated the effectiveness and safety of an intravitreal DEX implant in treating such conditions over a period of three to six months. For this reason, wisely selecting diabetic patients might be crucial to decreasing the load of injections in clinics and hospitals. The purpose of this review is to analyze the available scientific literature to highlight the benefits, efficacy, and clinical criteria for choosing whether to switch from intravitreal anti-VEGF therapy to an intravitreal DEX implant in diabetic macular edema.

Near vision in patients with DME and RVO treated with aflibercept and correlation with NEI VFQ-25 questionnaire

BACKGROUND

The aim of this study is to evaluate near and distance visual acuity (VA) and their correlation with the National Eye Institute Visual Function Questionnaire (NEI VFQ-25) outcomes in patients with diabetic macular edema (DME) and macular edema due to retinal vein occlusion (RVO) treated with aflibercept.

METHODS

In this prospective study, we included 87 eyes of patients diagnosed with DME (n = 61) and RVO (n = 26), who received aflibercept treatment and were followed until the 8th injection. Near VA was examined on the 1st, 2nd, 3rd, 4th, 6th, and 8th injection, and patients completed the NEI VFQ-25 on the 1st, 4th, and 8th aflibercept injection.

RESULTS

The mean near VA at baseline in all eyes was 0.89 ± 0.12 logMAR. With every administration, there was a statistically significant improvement; on the 4th (0.70 ± 0.19; p = 0.000) and the 8th application (0.60 ± 0.19; p = 0.000). At baseline, the mean NEI VFQ-25 total score was 71 ± 14%, and improved to 81 ± 13% (p = 0.000) on the 8th injection. The most significant score gain was recorded in the near VA subscale (+ 20 ± 14%, p = 0.000). There was no statistically significant difference between DME and RVO group in the questionnaire or near VA outcomes.

CONCLUSION

Aflibercept treatment resulted in a remarkable improvement of near vision by 4 lines of logMAR optotype after the 8th application. The near vision questionnaire subscale, initially scoring the lowest, exhibited the greatest gain during the treatment period. This underscores the importance of near vision and reading ability for patients with DME and RVO.

Aflibercept Off-Target Effects in Diabetic Macular Edema: An In Silico Modeling Approach

Intravitreal aflibercept injection (IAI) is a treatment for diabetic macular edema (DME), but its mechanism of action (MoA) has not been completely elucidated. Here, we aimed to explore IAI's MoA and its multi-target nature in DME pathophysiology with an in silico (computer simulation) disease model. We used the Therapeutic Performance Mapping System (Anaxomics Biotech property) to generate mathematical models based on the available scientific knowledge at the time of the study, describing the relationship between the modulation of vascular endothelial growth factor receptors (VEGFRs) by IAI and DME pathophysiological processes. We also undertook an enrichment analysis to explore the processes modulated by IAI, visualized the effectors' predicted protein activity, and specifically evaluated the role of VEGFR1 pathway inhibition on DME treatment. The models simulated the potential pathophysiology of DME and the likely IAI's MoA by inhibiting VEGFR1 and VEGFR2 signaling. The action of IAI through both signaling pathways modulated the identified pathophysiological processes associated with DME, with the strongest effects in angiogenesis, blood-retinal barrier alteration and permeability, and inflammation. VEGFR1 inhibition was essential to modulate inflammatory protein effectors. Given the role of VEGFR1 signaling on the modulation of inflammatory-related pathways, IAI may offer therapeutic advantages for DME through sustained VEGFR1 pathway inhibition.

Applications of nanomaterials in anti-VEGF treatment for ophthalmic diseases

Angiogenesis has been determined to be essential in the occurrence and metastasis of diabetic retinopathy (DR), age-related macular degeneration (AMD), retinal vein occlusion (RVO), choroidal neovascularization (CNV), retinopathy of prematurity (ROP), tumor, etc. However, the clinical use of anti-vascular endothelial growth factors (VEGF) drugs is currently limited due to its high cost, potential side effects, and need for repeated injections. In recent years, nanotechnology has shown promising results in inhibiting neovascularization and reducing reactive oxygen species (ROS) or inflammatory factors. Some nanomaterials can also act as vehicles for drug delivery, such as lipid nanoparticles and PLGA. The process of angiogenesis and its molecular mechanism are discussed in this article. At the same time, this study aims to systematically review the research progress of nanotechnology and offer more treatment options for neovascularization-related diseases in clinical ophthalmology.

Levosulpiride for the treatment of diabetic macular oedema: a phase 2 randomized clinical trial

BACKGROUND/OBJECTIVE

The prokinetic levosulpiride elevates vasoinhibin levels in the vitreous of patients with proliferative diabetic retinopathy (PDR) suggesting clinical benefits due to the anti-vasopermeability and anti-angiogenic properties of vasoinhibin. We investigated the biological activity of levosulpiride in centre-involving diabetic macular oedema (DME).

PATIENTS/METHODS

Prospective, randomized, double-blinded, dual-centre, phase 2 trial in patients with centre-involving DME orally treated with placebo (n = 17) or levosulpiride (n = 17) for 8 weeks or in patients with PDR undergoing elective pars plana vitrectomy and receiving placebo (n = 18) or levosulpiride (n = 18) orally for the 1 week before vitrectomy.

RESULTS

Levosulpiride improved changes from baseline in best-corrected visual acuity (p ≤ 0.037), central foveal thickness (CFT, p ≤ 0.013), and mean macular volume (MMV, p ≤ 0.002) at weeks 4, 6, and 8 compared to placebo. At 8 weeks, the proportion of eyes gaining ≥5 ETDRS letters at 4 m (41% vs. 28%), losing ≥21 μm in CFT (55% vs. 28%), and dropping ≥0.06 mm3 in MMV (65% vs. 29%) was higher after levosulpiride than placebo. The overall grading of visual and structural parameters improved with levosulpiride (p = 0.029). Levosulpiride reduced VEGF (p = 0.025) and PlGF (p = 0.008) levels in the vitreous of PDR patients. No significant adverse side-effects were detected.

CONCLUSIONS

Oral levosulpiride for 8 weeks improved visual and structural outcomes in patients with centre-involving DME by mechanisms that may include intraocular upregulation of vasoinhibin and downregulation of VEGF and PlGF. Larger clinical trials evaluating long-term efficacy and safety are warranted.

A Review on Diabetic Retinopathy

Diabetic retinopathy is a well-recognised microvascular complication of diabetes and is among the leading cause of blindness all over the world. Over the last decade, there have been advances in the diagnosis of diabetic retinopathy and diabetic macular edema. At the same time, newer therapies for the management of diabetic retinopathy have evolved. As a result of these advances, a decline in severe vision loss due to diabetes has been witnessed in some developing countries. However, there is a steady increase in the number of people affected with diabetes, and is expected to rise further in the coming years. Therefore, it is prudent to identify diabetic retinopathy, and timely intervention is needed to decrease the burden of severe vision loss. An effort has been made to review all the existing knowledge regarding diabetic retinopathy in this article and summarize the present treatment options for diabetic retinopathy.

Study of aqueous humour inflammatory mediators' levels in a cohort of Egyptian patients with diabetic macular oedema

BACKGROUND

The aim was to study aqueous humour inflammatory mediators' levels in a cohort of Egyptian patients with diabetic macular oedema (DMO).

METHODS

This was a case-control prospective study conducted on 2 groups: 25 eyes of 22 (11 females) patients seeking treatment for DMO as patients group, and 10 eyes of 10 (4 females) cataract patients as a control group. Aqueous humour was aspirated before intravitreal injection (patients' group) or cataract surgery (control group). Inflammatory mediators in aqueous humour were measured using a multiplex bead immunoassay kit of 27 pre-mixed cytokines.

RESULTS

Eotaxin, interferon gamma-induced protein 10 (IP-10), monocyte chemoattractant protein-1 (MCP-1/CCL2) and interleukin-8 (IL-8/CXCL8) were found significantly higher in patients' group compared to control group (p = 0.043, 0.037, 0.001, 0.015 respectively). On the contrary, interferon-gamma (IFN-gamma) and granulocyte colony-stimulating factor (G-CSF) were found significantly higher in control group than patients' group (p = 0.003, 0.019 respectively). Basic fibroblast growth factor (Basic-FGF/FGF-2) and interleukin-1 receptor antagonist (IL-1ra) were found higher (but not statistically significant) in controls (p = 0.100 and 0.070 respectively). Additionally, a negative and significant correlation was found between Eotaxin level in aqueous humour and central macular thickness.

CONCLUSIONS

Some mediators might be implicated in the pathogenesis of DMO either augmenting or suppressing role. Eotaxin, IP-10, MCP-1 and IL-8 might have a role in cases not responding to standard anti-vascular endothelial growth factor (VEGF) therapy. IL-1ra might have a protective role; therefore, the effectiveness of intravitreal injection of IL-1ra homologue needs to be studied in future clinical trials.

OCT-angiography based artificial intelligence-inferred fluorescein angiography for leakage detection in retina [Invited]

Optical coherence tomography angiography (OCTA) covers most functions of fluorescein angiography (FA) when imaging the retina but lacks the ability to depict vascular leakage. Based on OCTA, we developed artificial intelligence-inferred-FA (AI-FA) to delineate leakage in eyes with diabetic retinopathy (DR). Training data of 19,648 still FA images were prepared from FA-photo and videos of 43 DR eyes. AI-FA images were generated using a convolutional neural network. AI-FA images achieved a structural similarity index of 0.91 with corresponding real FA images in DR. The AI-FA generated from OCTA correctly depicted vascular occlusion and associated leakage with enough quality, enabling precise DR diagnosis and treatment planning. A combination of OCT, OCTA, and AI-FA yields more information than real FA with reduced acquisition time without risk of allergic reactions.

Diabetic retinopathy in African-Americans with end-stage kidney disease: a cross-sectional study on prevalence and impact on quality of life

INTRODUCTION

The prevalence, severity, and quality of life (QoL) impact of diabetic retinopathy (DR) among African-Americans (AAs) with end-stage kidney disease (ESKD) undergoing dialysis are unknown.

RESEARCH DESIGN AND METHODS

A cross-sectional study was conducted on 93 AA adults with diabetes and ESKD. The diagnosis of DR was based on a review of medical records and/or a positive photograph with a portable hand-held device reviewed by both artificial intelligence software and a retinal specialist. QoL, physical disability social determinants of health (SDoHs) were assessed by standardized questionnaires.

RESULTS

The prevalence of DR was 75%, with 33% of participants having mild, 9.6% moderate and 57.4% severe DR. A total of 43% had normal visual acuity; 45% had moderate visual impairment; and 12% had severe visual impairment. We found a high burden of disease, multiple SDoH challenges, and low QoL and general health among patients with ESKD. The presence of DR had no significant impact on physical health and QoL compared with participants without DR.

CONCLUSIONS

DR is present in 75% of AA patients with diabetes and ESKD on haemodialysis. ESKD has a significant burden on general health and QoL; however, DR has a minor additional impact on the overall physical health and QoL in people with ESKD.

Predictive factors for treatment outcomes with intravitreal anti-vascular endothelial growth factor injections in diabetic macular edema in clinical practice

BACKGROUND

Intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections are the standard of care for diabetic macular edema (DME), a common complication of diabetes. This study aimed to identify factors influencing DME intravitreal anti-VEGF treatment outcomes in real-world practice.

METHODS

This was a multi-center retrospective observational study using medical chart review of participants receiving anti-VEGF injections for DME (N = 248). Demographic and clinical variables were assessed for association with best corrected visual acuity (BCVA) and central macular thickness (CMT) outcomes using regression models.

RESULTS

There was a significant improvement in BCVA (p < 0.001) and CMT (p < 0.001) after 12 months of treatment, although 21% of participants had decreased BCVA, and 41% had a < 10% CMT reduction at 12 months. Higher baseline BCVA (p = 0.022, OR=-0.024, 95% CI=-0.046,-0.004) and longer duration of diabetic retinopathy (p = 0.048, OR=-0.064, 95% CI=-0.129,-0.001) were negative predictors for BCVA response, whereas Aflibercept treatment (p = 0.017, OR = 1.107, 95% CI = 0.220,2.051) compared with other drugs and a positive "early functional response" (p < 0.001, OR=-1.393, 95% CI=-1.946,-0.857) were positive predictors. A higher baseline CMT (p < 0.001, OR = 0.019, 95% CI = 0.012,0.0261) and an "early anatomical response", (p < 0.001, OR=-1.677, 95% CI=-2.456, -0.943) were predictors for greater reduction in CMT. Overall, the variables could predict only 23% of BCVA and 52% of CMT response.

CONCLUSIONS

The study shows a significant proportion of DME patients do not respond to anti-VEGF therapy and identifies several clinical predictors for treatment outcomes.

TRIAL REGISTRATION

The study was approved through the Human Research Ethics Committee, University of Tasmania (approval number H0012902), and the Southern Adelaide Clinical Human Research Ethics Committee (approval number 86 - 067).

REal-world treatment outcomes after delayed intRavitreal therapy in center-involving diabetic macular edema - RETORT study

PURPOSE

To compare real-life data on delayed intravitreal treatment of diabetic macular edema (DME) patients to early treatment.

METHODS

In this single-centre, retrospective, interventional, comparative study, DME patients were divided into two groups based on when they received treatment: Group 1 - received treatment within 24 weeks and Group 2 - at or after 24 weeks from the time of treatment advice. Visual acuity and central subfield thickness (CSFT) changes were compared at various time points. Reasons for delaying treatment were noted.

RESULTS

The study included 109 (Group 1-94; Group 2-15) eyes. When treatment was advised, demographic profile, diabetes duration, glucose control and VA between two groups were comparable. At this point, CSFT was higher in Group 1 than in Group 2 (p = 0.036). At injection time, Group 2 had better VA and lower CSFT than Group 1 (p < 0.05). Group 2's VA (53.4 ± 12.67) was significantly lower than Group 1's (57.38 ± 20.01) after 1-year treatment. At 1-year, CSFT decreased in Group 1 and increased in Group 2. Group 1 had mean improvement of + 7.6 letters and Group 2 had a decline of -6.9 letters. Group 2 required more intravitreal anti-VEGF (median - 3; IQR: 2-4), steroid injections (median - 4; IQR: 2-4) and focal laser sessions (median - 4; IQR: 2-4).

CONCLUSION

Late-treated DME eyes needed more injections and focal laser sessions than early treated eyes. Adherence to early treatment of DME in real-life will help prevent long-term vision loss.

Models and Algorithms for the Refinement of Therapeutic Approaches for Retinal Diseases

We are developing a Virtual Eye for in silico therapies to accelerate research and drug development. In this paper, we present a model for drug distribution in the vitreous body that enables personalized therapy in ophthalmology. The standard treatment for age-related macular degeneration is anti-vascular endothelial growth factor (VEGF) drugs administered by repeated injections. The treatment is risky, unpopular with patients, and some of them are unresponsive with no alternative treatment. Much attention is paid to the efficacy of these drugs, and many efforts are being made to improve them. We are designing a mathematical model and performing long-term three-dimensional Finite Element simulations for drug distribution in the human eye to gain new insights in the underlying processes using computational experiments. The underlying model consists of a time-dependent convection-diffusion equation for the drug coupled with a steady-state Darcy equation describing the flow of aqueous humor through the vitreous medium. The influence of collagen fibers in the vitreous on drug distribution is included by anisotropic diffusion and the gravity via an additional transport term. The resulting coupled model was solved in a decoupled way: first the Darcy equation with mixed finite elements, then the convection-diffusion equation with trilinear Lagrange elements. Krylov subspace methods are used to solve the resulting algebraic system. To cope with the large time steps resulting from the simulations over 30 days (operation time of 1 anti-VEGF injection), we apply the strong A-stable fractional step theta scheme. Using this strategy, we compute a good approximation to the solution that converges quadratically in both time and space. The developed simulations were used for the therapy optimization, for which specific output functionals are evaluated. We show that the effect of gravity on drug distribution is negligible, that the optimal pair of injection angles is (50∘,50∘), that larger angles can result in 38% less drug at the macula, and that in the best case only 40% of the drug reaches the macula while the rest escapes, e.g., through the retina, that by using heavier drug molecules, more of the drug concentration reaches the macula in an average of 30 days. As a refined therapy, we have found that for longer-acting drugs, the injection should be made in the center of the vitreous, and for more intensive initial treatment, the drug should be injected even closer to the macula. In this way, we can perform accurate and efficient treatment testing, calculate the optimal injection position, perform drug comparison, and quantify the effectiveness of the therapy using the developed functionals. We describe the first steps towards virtual exploration and improvement of therapy for retinal diseases such as age-related macular degeneration.

Topical treatment of diabetic macular edema using dexamethasone ophthalmic suspension: A randomized, double-masked, vehicle-controlled study

PURPOSE

To evaluate topical dexamethasone ophthalmic suspension OCS-01 (Oculis SA, Lausanne, Switzerland) in diabetic macular edema (DME).

METHODS

This was a multicenter, double-masked, parallel-group, randomized, Phase 2 study. Patients aged 18-85 years with DME of <3 years duration, ETDRS central subfield thickness ≥ 310 μm by SD-OCT, and ETDRS letter score ≤ 73 and ≥ 24 in the study eye were randomized 2:1 to OCS-01 or matching vehicle, 1 drop 3 times/day for 12 weeks. Efficacy was evaluated as change from baseline to Week 12 of ETDRS letter score and central macular thickness (CMT). The primary analysis used a linear model with baseline ETDRS letters as a covariate, and missing data imputed using multiple imputation pattern mixture model techniques. Active treatment was considered superior to vehicle if the one-sided p-value was <0.15 and the difference in mean change from baseline in ETDRS letters was >0.

RESULTS

Mean CMT showed a greater decrease from baseline with OCS-01 (N = 99) than vehicle (N = 45) at Week 12 (-53.6 vs -16.8 μm, p = 0.0115), with significant differences favouring OCS-01 from Weeks 2 to 12. OCS-01 was well-tolerated, and increased intraocular pressure was the most common adverse event. Mean change in ETDRS letter score from baseline to Week 12 met the p was +2.6 letters with topical OCS-01 and 1 letter with vehicle (p = 0.125). In a post-hoc analysis, there was a greater difference in patients with baseline BCVA ≤65 letters, the OCS-01 group improved 3.8 letters compared with 0.9 letters with vehicle.

CONCLUSION

Topical OCS-01 was significantly more effective than vehicle in improving central macular thickness in patients with DME. Visual improvement was better in eyes with lower baseline vision.

Vitrectomy with ILM peeling in diabetic macular edema in one eye vs. intravitreal anti-VEGF injections in the second eye: a comparative study

PURPOSE

The aim of this study was to compare the results of vitrectomy performed in patients' worse eyes with diabetic macular edema to the results of continuous anti-VEGF treatment performed in patients' fellow eyes.

METHODS

A retrospective interventional study of 14 patients with diabetic macular edema in both eyes. The better eye was always qualified for aflibercept injections (group 1), and the worse eye was scheduled for vitrectomy (group 2). The follow-up lasted 12 months. The following parameters were measured: visual acuity (V), central retinal thickness (CRT), maximum retinal thickness (MRT), central choroidal thickness (CCT), superficial fovea avascular zone (sFAZ) and deep fovea avascular zone (dFAZ), and vessel density at the level of superficial (sVD) and deep (dVD) retinal vessels.

RESULTS

None of the analyzed factors differed between groups with statistical significance at any timepoint. The time of recovery of vision was identical in both eyes (F = 0.91, p = 0.449). The final sFAZ was significantly smaller for group 2 (median 196 μm) than for group 1 (median 375 μm; U = 101.0; p = 0.022; r = 0.44).

CONCLUSION

Both techniques resulted in similar improvements in visual acuity and decreases in CRT after 1 year. sFAZ decreased in all eyes, with a higher extent after vitrectomy.

Sustained therapeutic effect of an anti-inflammatory peptide encapsulated in nanoparticles on ocular vascular leakage in diabetic retinopathy

Pigment epithelium-derived factor (PEDF), an endogenous Wnt signaling inhibitor in the serine proteinase inhibitors (SERPIN) super family, is present in multiple organs, including the vitreous. Significantly low levels of PEDF in the vitreous are found to associate with pathological retinal vascular leakage and inflammation in diabetic retinopathy (DR). Intravitreal delivery of PEDF represents a promising therapeutic approach for DR. However, PEDF has a short half-life after intravitreal injection, which represents a major hurdle for the long-term treatment. Here we report the prolonged therapeutic effects of a 34-mer peptide of the PEDF N-terminus, encapsulated in poly (lactic-co-glycolic acid) (PLGA) nanoparticles (PEDF34-NP), on DR. PEDF34-NP inhibited hypoxia-induced expression of vascular endothelial growth factor and reduced levels of intercellular adhesion molecule 1 (ICAM-1) in cultured retinal cells. In addition, PEDF34-NP significantly ameliorated ischemia-induced retinal neovascularization in the oxygen-induced retinopathy rat model, and significantly reduced retinal vascular leakage and inflammation in streptozotocin-induced diabetic rats up to 4 weeks after intravitreal injection, as compared to PLGA-NP control. Intravitreal injection of PEDF34-NP did not display any detectable toxicities to retinal structure and function. Our findings suggest that PEDF34-NP can confer sustained therapeutic effects on retinal inflammation and vascular leakage, having considerable potential to provide long-term treatment options for DR.

Real-world cost-effectiveness of anti-VEGF monotherapy and combination therapy for the treatment of polypoidal choroidal vasculopathy

OBJECTIVES

For patients with polypoidal choroidal vasculopathy (PCV), intravitreal anti-vascular endothelial growth factor (anti-VEGF) combination therapy has been shown to be cost-saving relative to monotherapy in a clinical trial setting. However, whether this also applies to real-world settings is unclear. We aim to compare the real-world functional outcomes and cost-effectiveness of intravitreal anti-VEGF combination therapy relative to monotherapy, to investigate whether combination therapy is truly cost-saving.

METHODS

We used a Markov model to simulate a hypothetical cohort of PCV patients treated at Singapore National Eye Centre. Model parameters were informed by coarsened exact matched estimates of a two-year retrospective study of patients who initiated treatment in 2015. Treatment options included intravitreal aflibercept, bevacizumab, or ranibizumab, as monotherapy or in combination with full-fluence verteporfin photodynamic therapy.

RESULTS

The two-year logMAR letters gains were significant for combination therapy ( + 10.6, P = 0.006) but not monotherapy (-2.2, P = 0.459). Over 20 years, a PCV patient would cost the health system SGD 48,790 under monotherapy and SGD 61,020 under combination therapy. Quality-adjusted life-years (QALYs) were estimated to be 7.41 for monotherapy and 7.80 for combination therapy. The incremental cost-effectiveness ratio of combination therapy was SGD 31,460/QALY, which is less than the common willingness-to-pay threshold of per capita gross domestic product of Singapore (SGD 88,990/QALY). Sensitivity analysis showed that combination therapy remained incrementally cost-effective, but not cost-saving.

CONCLUSIONS

Our study shows that combination therapy is good value for money but is likely to increase costs when applied in real-world settings.

Short-term outcomes in patients with center-involving diabetic macular edema after a single dose of intravitreal bevacizumab

Background

A significant portion of diabetic macular edema (DME) is refractory to anti-vascular endothelial growth factor (anti-VEGF) agents. This study investigates morphological and functional outcomes to a single intravitreal bevacizumab (IVB) injection in patients with center-involving DME (ciDME) at 4–6 weeks and compares treatment responders and non-responders based on spectral domain optical coherence tomography (SD-OCT) features.

Methods

IRB approved observational, retrospective chart review of patients with ciDME, identified by ICD-10 code, who received IVB and underwent baseline and 4–6 weeks follow-up SD-OCT imaging between January 1, 2016 and January 19, 2021. Patients who had received previous treatment with anti-VEGF or intraocular steroids within 1 year were excluded. Variables included best-corrected visual acuity (BCVA), central subfield thickness (CST) and total macular volume (TMV). Eyes were classified as responders if CST reduction was greater than 10%. OCT scans were graded qualitatively by two masked graders using Imagivault software. Paired Student’s t-tests, Wilcoxon signed rank tests and Chi-Square tests were used for analysis.

Results

A total of 334 prospective subjects were identified, and after applying exclusion criteria 52 eyes from 46 patients (mean age 64.22 ± 8.12 years, 58.7% male) were included. Mean BCVA did not significantly change with treatment, 63.9 ETDRS letters (~ 20/50) at baseline and 65.9 ETDRS letters (~ 20/50) post-treatment (p = 0.07). Mean CST decreased from 466 ± 123 μm at baseline to 402 ± 86 μm post-treatment (p < 0.001). 22 (42.3%) of eyes were categorized as responders and 30 (57.7%) as non-responders. Average change in CST from baseline in responders was -164 μm (p < 0.001) and + 9 μm in non-responders (p = 0.47). Vitreomacular adhesion (VMA) was more prevalent in non-responders (28.7% vs. 4.8%, p = 0.03). In addition, cyst location in the inner nuclear layer (INL) was present more frequently in responders (95.5% vs. 73.3%, p = 0.037) as was subretinal fluid (45.5% vs. 13.3%, p = 0.01).

Conclusion

The short-term response to a single IVB was sub-optimal with structural but no functional improvements. Greater baseline CST, presence of INL cysts and subretinal fluid may represent factors indicative of a better treatment response.

Characteristics of macular morphology and microcirculation in diabetic macular edema patients with serous retinal detachment

BACKGROUND

To analyze and compare the characteristics of macular morphology and microcirculation in diabetic macular edema (DME) patients with and without macular serous retinal detachment (SRD).

METHODS

One hundred eyes in 81 patients diagnosed with the DME (the central macular thickness (CMT) of ≥ 300 μm) from March 2020 to November 2020 were selected. According to whether complicated with SRD, patients were divided into DME with SRD (60 eyes) and without SRD (40 eyes) groups. We analyzed the following parameters: CMT, central retinal thickness (CRT), subfoveal choroidal thickness (SFCT), number of hyperreflective foci (HF) in the complete retina, inner retina, outer retina, and subretinal space, the integrity of the ellipsoid zone (EZ) and external limiting membrane (ELM), the presence of disorganization of inner retinal layers (DRIL), foveal avascular zone (FAZ) area, and the vascular flow density of superficial capillary plexus (SCP), deep capillary plexus (DCP), and choriocapillaris.

RESULTS

(1) Compared to the group without SRD, the group with SRD had a greater CMT (P < 0.05) and a smaller CRT (P < 0.001); (2) The number of the HF in the complete retina, outer retina, and the subretinal space was larger in the group with SRD (P < 0.001); 3.The proportion of the EZ disruption (P < 0.05) and ELM disruption (P < 0.001) were higher in the group with SRD; 4. The SFCT (P < 0.05) and the vascular flow density of choriocapillaris (P < 0.05) were greater in the group with SRD; 5. There were no significant differences in the FAZ area and the vascular flow density of the DCP and SCP (P > 0.05); 6. The presence of the SRD was correlated with the integrity of the ELM, the number of HF in the complete retina, outer retina, and subretinal space (χ2 = 26.930, OR = 0.707, 0.263, 0.995, P < 0.001), as well as the SFCT (OR = 0.992, P < 0.05).

CONCLUSIONS

The results support the hypothesis that the presence of the ELM disruption, the larger number of the HF, and the thickening and hyperperfusion of the choroid may be involved in the pathogenesis of SRD in DME.

The Role of Intravitreal Corticosteroids in the Treatment of DME: Predictive OCT Biomarkers

This work aims to summarize predictive biomarkers to guide treatment choice in DME. Intravitreal anti-VEGF is considered the gold standard treatment for centers involving DME, while intravitreal steroid treatment has been established as a second-line treatment in DME. However, more than 1/3 of the patients do not adequately respond to anti-VEGF treatment despite up to 4-weekly injections. Not surprisingly, insufficient response to anti-VEGF therapy has been linked to low-normal VEGF levels in the serum and aqueous humor. These patients may well benefit from an early switch to intravitreal steroid treatment. In these patients, morphological biomarkers visible in OCT may predict treatment response and guide treatment decisions. Namely, the presence of a large amount of retinal and choroidal hyperreflective foci, disruption of the outer retinal layers and other signs of chronicity such as intraretinal cysts extending into the outer retina and a lower choroidal vascular index are all signs suggestive of a favorable treatment response of steroids compared to anti-VEGF. This paper summarizes predictive biomarkers in DME in order to assist individual treatment decisions in DME. These markers will help to identify DME patients who may benefit from primary dexamethasone treatment or an early switch.

Diabetic Macular Edema Treatment: Laser Photocoagulation Versus anti-VEGF Drugs

Abstract: Objective: The present study was aimed to compare best-corrected vision and central macular thickness for macular edema in diabetes (DME) after utilizing laser, Avastin, and Lucentis. Methods: A retrospective randomized cross-sectional study was conducted at Alfaisal Eye Center, Khartoum. Best-corrected vision and central macular thickness (CMT) were assessed by Snellen's chart and Heidelberg optical coherence tomography OCT, respectively. Results: In this study, a total of 252 records of DME-treated patients with laser applications, Avastin, and Lucentis were enrolled, their mean age was 57 ± 5.22 yrs. A significant enhancement in best-corrected vision and CMT of studied groups with laser applications, Avastin, and Lucentis was obtained (P= 0.000) with no differences between treated groups (p= 0.445 and 0,479), respectively. Non-significant differences in variable measurements related to gender or age (p = 0.117, 0.781), respectively. CMT of females (260 ± 48 μm) was thinner than males (306 ± 74 μm) after treatment (P = 0.000). Conclusion: laser applications, Avastin, and Lucentis improved best-corrected vision and reduced central macular thickness significantly with no clear differences between studied groups. Age or gender have a non-significant impact on dependent variables. Females gained thinner results compared to males after treatment.  

Final Outcomes from the Randomized RECOVERY Trial of Aflibercept for Retinal Nonperfusion in Proliferative Diabetic Retinopathy

PURPOSE

Retinal nonperfusion (RNP) is an important biomarker for diabetic retinopathy (DR). Data suggest that consistent anti-VEGF pharmacotherapy can slow RNP development. The RECOVERY trial evaluated the impact of aflibercept (Eylea, Regeneron) on RNP among eyes with proliferative DR (PDR).

DESIGN

Prospective, randomized clinical trial with treatment crossover in the second year.

SUBJECTS

Eyes with PDR and RNP.

METHODS

At baseline, the subjects were randomized 1:1 to monthly (arm 1) or quarterly (arm 2) intravitreal 2 mg aflibercept. At the beginning of year 2, the treatment arms were crossed over so that the monthly-dosed subjects subsequently received quarterly dosing and the quarterly-dosed subjects subsequently received monthly dosing.

MAIN OUTCOME MEASURES

Change in total RNP area (mm²) through year 2. Secondary outcomes included Diabetic Retinopathy Severity Scale (DRSS) scores; best-corrected visual acuity; central subfield thickness; additional measures of RNP, including ischemic index (ISI); and adverse event incidence. Means and 95% confidence intervals were calculated.

RESULTS

Among all subjects, from baseline to year 2, the mean RNP increased from 235 mm² to 402 mm² (P < 0.0001), and the ISI increased from 25.8% to 50.4% (P < 0.0001). Increases in the mean RNP (P < 0.0001) and ISI (P < 0.0001) were also observed from year 1 to year 2. The mean total RNP increased from 264 mm² at baseline to 386 mm² (P < 0.0001) at year 2 in arm 1 and from 207 mm² at baseline to 421 mm² (P < 0.0001) at year 2 in arm 2 (P = 0.023, arm 1 vs. arm 2). Increases in the mean RNP for both treatment arms (P < 0.0001) were also specifically observed within year 2 (P = 0.32, arm 1 vs. arm 2). Compared with baseline, the DRSS scores at the end of year 2 improved in 82% (n = 27) of subjects and remained stable in 18% (n = 6), with no subjects experiencing worsening; at 2 years, the DRSS scores had improved by 2 or more steps in 65% (n = 11) and 81% (n = 13) of subjects in arms 1 and 2, respectively.

CONCLUSIONS

Through year 2 of the RECOVERY trial, both treatment arms experienced significant increases in RNP. Despite the expansion of the RNP area in nearly all subjects, 82% of subjects demonstrated an improvement in DRSS levels from baseline, with no subjects experiencing worsening in DRSS scores.

One-Month Outcomes of Intravitreal Anti-VEGF vs. Dexamethasone Implant in the Treatment of Diabetic Macular Edema in Vitrectomized Eyes

Objectives

To compare short-term effect of intravitreal ranibizumab with dexamethasone implant for diabetic macular edema (DME) in vitrectomized eyes.

Methods

Single-center, prospective, randomized study of vitrectomized eyes with DME. Study eyes were divided into two groups, receiving ranibizumab (IVV group, n = 35 eyes) or dexamethasone implant (IVD group, n = 35 eyes) respectively. Patients were evaluated at baseline, Week 1 and Month 1. The main outcome measures included best-corrected visual acuity (BCVA), central retinal thickness (CRT) and intraocular pressure (IOP).

Results

BCVA and CRT were similar in the two groups at baseline. At Week 1, the CRT improvement was significant in two groups (P = 0.041 in IVV group, P = 0.030 in IVD group), but at Month 1, only IVD group had significant improvement in CRT (P < 0.001). And BCVA gains were significant at Week 1 (P = 0.029) and Month 1 (P = 0.001) in IVD group, whereas IVV group did not show significant BCVA gains (P = 0.056 at Week1, P = 0.166 at Month 1). The changes of BCVA and CRT were significantly higher in IVD group than IVV group at Month1, but the changes were not significant at Week1.

Conclusions

Comparing to anti-VEGF therapy, DEX implant is more effect in improving BCVA and reducing CRT in vitrectomized eyes at 1 month, which indicated DEX implant is a better strategy.

Pascal short-pulse plus subthreshold endpoint management laser therapy for diabetic macular edema: the "sandwich technique"

Background

Diabetic macular edema (DME) is the main cause of visual loss in diabetic patients. Despite the use of anti-VEGF therapy as first-line treatment, there are many patients whose response to treatment is poor or transient at best. Sophisticated laser techniques have emerged aiming at low-intensity retinal damage, avoiding excessive heat that causes tissue necrosis and related collateral effects.

Objective

To evaluate the effect of combined sublethal laser modalities from short-pulse duration (SPD) with endpoint management (EpM) subthreshold laser [named the “sandwich technique” (SWiT)] on central subfield thickness (CST) and best-corrected visual acuity (BCVA) in patients with DME.

Material and methods

In this consecutive retrospective study, 37 patients (37 eyes) with center-involved (CI) DME were treated with SWiT laser therapy from April 2017 to June 2021. The technique consisted of a mean number of 200 (range number 50–400) SPD laser burns OCT-guided thickened area performed on the juxta- and perifoveal area 500 µm away from the foveal center, overlapping with a mean number of 1000 (range number 800–1200) EpM laser burns focused on 6 mm macular diameter area but saving 300 µm toward the foveal center. All patients underwent ophthalmological evaluations, including BCVA and CST measurement by spectral-domain optical coherence tomography (SD-OCT), before and after SWiT laser therapy. The mean follow-up time was 19.2 months (range 2–60 months).

Results

Thirty-five out of 37 cases showed an improvement in CST and BCVA following treatment. At baseline, mean CST (µm) ± standard error (SE) and mean BCVA (logMAR) ± SE was 456.95 ± 37.00 and 0.71 ± 0.29, respectively. After a mean follow-up of 19.2 months, mean CST (µm) ± SE and BCVA (logMAR) ± SE were 272.09 ± 9.10 (p < 0.0001) and 0.54 ± 0.26 (p = 0.003), respectively. A statistically significant reduction in CST and improvement in BCVA was noted after laser therapy application. The anti-VEGF injection frequency was reduced during the mean 19.2 months of the study period.

Conclusions

The novel “sandwich” laser therapy aid reduced CST and improved BCVA in this retrospective case series. Further prospective studies are warranted.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40942-022-00381-5.

Outcome of intravitreal Avastin® injections in patients with macular oedema in Uganda: a cohort study

Background

To determine the outcome of Intravitreal Avastin (IVA) injections in patients with Macular Oedema (MO) in Uganda.

Methods

We prospectively recruited patients presenting with MO at the Department of Ophthalmology of Mbarara University of Science and Technology in Southern Uganda from November 2018 to April 2019. We treated them with intravitreal injection of Bevacizumab (Avastin®) and followed them up for three consecutive months after the initial injection. We collected information on baseline clinical presentation and 3 month outcomes. We performed a Student’s t-test to compare central macular thickness (CMT) and best corrected visual acuity (BCVA) at baseline and at 3 months after IVA injections. We performed linear regression to test for predictors of change in CMT and BCVA at 3 months.

Results

We enroled 32 patients (35 eyes) of which 29 patients (32 eyes) completed the follow up. The mean age was 62.8 ± 11.8 years, and 53% were male. At 3 months after IVA, the mean CMT improved significantly from 426.90 ± 135.9 µm at baseline to 311.20 ± 134.80 µm (p = 0.0008). The mean BCVA improved from 0.70 ± 0.38 at baseline to 0.38 ± 0.36 logMAR units (p = 0.003). The improvement in CMT and BCVA were more marked in patients who had Diabetic ME compared to other causes. A high baseline CMT was a strong predictor of improvement in CMT at 3 months after IVA therapy. A worse baseline visual acuity was a predictor of improvement in vision at 3 months after IVA.

Conclusions

IVA therapy results in anatomical and visual improvement at 3 months especially in patients with Diabetic MO. Having a high baseline CMT was a predictor of good CMT outcome at 3 months while a worse vision at baseline was a predictor of better visual outcome at 3 months.

Full-Thickness Macular Hole Closure Following a Single Intravitreal Injection of Aflibercept in an Eye With Diabetic Macular Edema

Purpose:

This work aims to discuss the case of a 32-year-old man with diabetic macular edema (DME) who underwent successful treatment of a full-thickness macular hole (FTMH) with a single dose of aflibercept.

Methods:

A case report is presented.

Results:

A 32-year-old man with reduced vision and DME in the right eye was found to have a FTMH. The patient was scheduled for pars plana vitrectomy; however, following a single dose of intravitreal aflibercept, the FTMH closed and the patient avoided surgical intervention.

Conclusions:

FTMH formation in DME is a rare complication that typically requires surgical intervention. We present a case of FTMH closure after a single dose of intravitreal aflibercept, which to our knowledge is the first of its kind. This report highlights the importance of considering conservative treatment initially to avoid surgery.

Central Visual Function and Genotype-Phenotype Correlations in PDE6A-Associated Retinitis Pigmentosa

Purpose

Autosomal recessive retinitis pigmentosa (arRP) can be caused by mutations in the phosphodiesterase 6A (PDE6A) gene. Here, we describe the natural course of disease progression with respect to central retinal function (i.e., visual acuity, contrast sensitivity, and color vision) and establish a detailed genotype-–phenotype correlation.

Methods

Forty-four patients (26 females; mean age ± SD, 43 ± 13 years) with a confirmed genetic diagnosis of PDE6A-associated arRP underwent comprehensive ophthalmological examinations including best-corrected visual acuity (BCVA) with Early Treatment Diabetic Retinopathy Study charts, contrast sensitivity (CS) with Pelli–Robson charts at distances of 3 m and 1 m, and color vision testing using Roth 28-Hue and Panel D-15 saturated color cups.

Results

The most frequently observed variants were c.998+1G>A/p.?, c.304C>A/p.R102S, and c.2053G>A/p.V685M. Central retinal function in patients homozygous for variant c.304C>A/p.R102S was better when compared to patients homozygous for variant c.998+1G>A/p.?, although the former were older at baseline. Central retinal function was similar in patients homozygous for variant c.304C>A/p.R102S and patients heterozygous for variants c.304C>A/p.R102S and c.2053G>A/p.V685M, although the latter were younger at baseline. Annual decline rates in central retinal function were small.

Conclusions

We conclude that the severity of the different disease-causing PDE6A mutations in humans with respect to central visual function may be ranked as follows: c.2053G>A/p.V685M in homozygous state (most severe) > c.998+1G>A/p.? in homozygous state > c.304C>A/p.R102S and c.2053G>A/p.V685M in compound-heterozygous state > c.304C>A/p.R102S in homozygous state (mildest). The assessment of treatment efficacy in interventional trials will remain challenging due to small annual decline rates in central retinal function.

Costs comparison of treating diabetic macular edema with aflibercept, ranibizumab or dexamethasone at 1 year in France (INVICOST study)

PURPOSE

INVICOST, a medico-economic analysis, compared costs of managing treatment-naive patients with diabetic macular edema (DME) receiving intravitreal injections (IVIs) of aflibercept (AFL), dexamethasone implant (DXI) or ranibizumab (RAN) over 1 year.

METHODS

Healthcare resource use and associated costs were estimated using individual patient data from INVICTUS, a prospective, open-label, monocentric study. Healthcare costs comprised direct medical costs such as drug acquisition and administration, consultations and ophthalmological procedures. Costs were assessed from the French National Health Insurance perspective using published national tariffs expressed in 2019 euros.

RESULTS

Of the 60 treated eyes, 48 had no treatment switch; 14 received AFL, 19 received DXI and 15 received RAN. AFL-treated eyes received an average of 6.5 IVIs, DXI-treated patients received 2 IVIs and RAN-treated received 6.8 IVIs. All treated eyes received an initial prescription for adjunctive ocular medications and 349 follow-up procedures were performed including an average of 3.9 optical coherence tomography and 3.2 retinography procedures per eye. Average total direct cost of per-eye treatment was €4516 (€1128-€8257). Average cost was €5782 for eyes treated with AFL, €2779 with DXI and €5536 with RAN. Drug therapy was the cost driver: €4394 (76%) for AFL, €1915 for DXI (69%) and €4268 (77%) for RAN.

CONCLUSION

The difference in total treatment cost is largely explained by the significantly lower frequency of IVI and annual cost of therapy with DXI, compared with AFL and RAN. INVICOST is the first study comparing treatment costs with AFL, DXI and RAN in France in current clinical practice.

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.

Identifying Genetic Biomarkers Predicting Response to Anti-Vascular Endothelial Growth Factor Injections in Diabetic Macular Edema

Intraocular anti-vascular endothelial growth factor (VEGF) therapies are the front-line treatment for diabetic macular edema (DME); however, treatment response varies widely. This study aimed to identify genetic determinants associated with anti-VEGF treatment response in DME. We performed a genome-wide association study on 220 Australian patients with DME treated with anti-VEGF therapy, genotyped on the Illumina Global Screening Array, and imputed to the Haplotype Reference Consortium panel. The primary outcome measures were changes in central macular thickness (CMT in microns) and best-corrected visual acuity (BCVA in ETDRS letters) after 12 months. Association between single nucleotide polymorphism (SNP) genotypes and DME outcomes were evaluated by linear regression, adjusting for the first three principal components, age, baseline CMT/BCVA, duration of diabetic retinopathy, and HbA1c. Two loci reached genome-wide significance (p < 5 × 10−8) for association with increased CMT: a single SNP on chromosome 6 near CASC15 (rs78466540, p = 1.16 × 10−9) and a locus on chromosome 12 near RP11-116D17.1 (top SNP rs11614480, p = 2.69 × 10−8). Four loci were significantly associated with reduction in BCVA: two loci on chromosome 11, downstream of NTM (top SNP rs148980760, p = 5.30 × 10−9) and intronic in RP11-744N12.3 (top SNP rs57801753, p = 1.71 × 10−8); one near PGAM1P1 on chromosome 5 (rs187876551, p = 1.52 × 10−8); and one near TBC1D32 on chromosome 6 (rs118074968, p = 4.94 × 10−8). In silico investigations of each locus identified multiple expression quantitative trait loci and potentially relevant candidate genes warranting further analysis. Thus, we identified multiple genetic loci predicting treatment outcomes for anti-VEGF therapies in DME. This work may potentially lead to managing DME using personalized treatment approaches.

The sterility, stability and efficacy of repackaged ziv-aflibercept for intravitreal administration

To evaluate the sterility, stability, and efficacy of repackaged ziv-aflibercept in 1-mL plastic tuberculin syringes for intravitreal injection after storage for up to 90 days at controlled (4 °C) and ambient (25.8 °C) temperature. A total of 168 tuberculin-type 1-mL syringes were prepared containing ziv-aflibercept (100 mg/4 mL). Samples were stored at 4 °C and 25.8 °C for 0, 3, 7, 14, 21, 28, 60, and 90 days. At each time point, four samples were evaluated for the stability and binding affinity of anti-VEGF to VEGF (efficacy) using enzyme-linked immunosorbent assays (ELISAs). All samples were analyzed for microbial growth. No microbial growth was obtained from any of the ziv-aflibercept samples during each time point, indicating that the repackaged ziv-aflibercept stored at 4 °C and 25.8 °C remained sterile. ELISA analysis revealed no significant decrease in concentration, and binding affinity was observed, indicating that the stability and efficacy were preserved. However, the concentration of ziv-aflibercept decreased less than the minimum expected concentration of 8 ng/mL after 60 days at 4 °C and after 30 days at 25.8 °C. The repackaged anti-VEGF drug ziv-aflibercept does not lose stability or efficacy and remains uncontaminated if prepared under sterile conditions and stored at 4 °C for up to 60 days or stored at 25.8 °C for up to 30 days.

Transcytosis mechanisms of cell-penetrating peptides: Cation independent CC12 and cationic penetratin

Cell-penetrating peptides (CPPs) can aid in intracellular and in vivo drug delivery. However, the mechanisms of CPP-mediated penetration remain unclear, limiting the development and further application of CPPs. Flow cytometry and laser confocal fluorescence microscopy were performed to detect the effects of different endocytosis inhibitors on the internalization of CC12 and penetratin in ARPE-19 cells. The co-localization of CPPs with the lysosome and macropinosome was detected via an endocytosis tracing experiment. The flow cytometry results showed that chlorpromazine, wortmannin, cytochalasin D, and the ATP inhibitor oligomycin had dose-dependent endocytosis-inhibitory effects on CC12. The laser confocal fluorescence results showed that oligomycin had the most significant inhibitory effect on CC12 uptake; CC12 was co-located with the lysosome, but not with the macropinosome. For penetratin, cytochalasin D and oligomycin had obvious inhibitory effects. The laser confocal fluorescence results indicated that oligomycin had the most significant inhibitory effect on penetratin uptake; the co-localization of penetratin with the lysosome was higher than that with the macropinosome. Cation-independent CC12 and cationic penetratin may be internalized into cells primarily through caveolae and clathrin-mediated endocytosis, and they are typically dependent on ATP. The transport of penetratin could be partly achieved through the direct transmembrane pathway, as the positive charge of penetratin interacts with the negative charge of the cell membrane, and partly through the endocytic pathway.

Comparison of Innovator vs. Biosimilar Ranibizumab in Treating Diabetic Macular Edema: A Multicenter Retrospective Study

Introduction

To compare the efficacy of innovator ranibizumab (iRBZ—Accentrix, Novartis, India) vs. biosimilar ranibizumab (bRBZ, Razumab-Intas, India) in eyes with diabetic macular edema (DME) in an Indian population.

Methods

Data of patients with DME who underwent at least three injections of iRBZ or bRBZ and had a minimum of 6 months follow-up were obtained from an electronic database. Choice of injection depended upon the patient. Pro re nata (PRN) protocol from baseline was used with reinjections advised if the central macular thickness (CMT) was at least 300 μm and best corrected visual acuity (BCVA) was 20/40 or worse. Primary outcome measure was comparison of change in BCVA at 6 months between iRBZ and bRBZ.

Results

We included 264 eyes in the iRBZ group and 69 eyes in bRBZ group, which were comparable for baseline characteristics. Mean BCVA improved from 0.64 ± 0.39 logMAR to 0.47 ± 0.31 logMAR (p < 0.001) in the iRBZ group and from 0.71 ± 0.42 logMAR to 0.50 ± 0.29 logMAR in the bRBZ group (p < 0.001) at 6 months. There were no differences in BCVA between the two groups (p > 0.05 for all time points). The CMT reduction in the iRBZ group (120 ± 196 µm) was comparable to that in the bRBZ group at 6 months (105 ± 187 µm) (p = 0.69). There was no difference in the mean number of injections taken (3.81 ± 1.2 in iRBZ vs. 3.55 ± 1.2 in bRBZ) (p > 0.05) between groups. Vision at baseline was the only factor associated with vision at last follow-up after adjusting for CMT at baseline, type of injection, and number of injections.

Conclusions

Biosimilar RBZ is similar to innovator RBZ in improving vision and reducing CMT in eyes with DME in the short term.

Expression of Long Non-Coding RNA (lncRNA) SNHG5 in Patients with Refractory Diabetic Macular Edema and Its Regulatory Mechanism

BACKGROUND The aim of this study was to assess use of lncRNAs as biomarkers in serum and aqueous humor of patients with diabetic macular edema (DME). MATERIAL AND METHODS Optical coherence tomography and fundus photography were used to analyze the retinal features of the patients. RT-qPCR was used to analyze the differential expression of lncRNA snhg5 in patients who have idiopathic macular hole (MH), DME, or refractory DME. The relationship between SNHG5 and the clinical characteristics of the patients was analyzed. The effect of SNHG5 on the hyperplasia and apoptosis of human retino-microvascular endothelial cells (HRMECs) and its mechanism were analyzed in vitro. RESULTS Patients with idiopathic MH developed retinal nerve epithelium rupture and retinal fundus thickening, and patients with DME or refractory DME showed significant macular edema with hemorrhaging. The refractory DME patients improved after treatment but still showed significant macular edema and multiple laser scarring. SNHG5 expression was not only low in the atrial fluid and plasma in DME patients, but also lower in the refractory DME group compared to the idiopathic MH patients. SNHG5 expression in the aqueous humor and plasma was negatively correlated with disease duration, body mass index, and levels of fasting blood glucose, glycated hemoglobin, proteinuria, and glycosuria. In the in vitro experiments, SNHG5 expression was significantly downregulated in high glucose-induced HMECs. After SNHG5 overexpression, cell proliferation, angiogenesis, and VEGF-A protein levels were distinctly downregulated. CONCLUSIONS SNHG5 correlates with the development of DME and is a potential target for therapy.

LUCENTIS IN THE TREATMENT OF DIABETIC MACULAR EDEMA, TWO-YEAR RESULTS

AIM

To evaluate, on the basis of two-year observations, the effectiveness of intravitreal treatment with Ranibizumab in patients with diabetic macular edema (DME) unresponsive to the previous laser treatment. Cohort and Methods: A retrospective study evaluates 29 eyes of 29 patients with diffuse DME unresponsive to their previous laser treatment. The group of the patients consisted of 16 males (55.1%) and 13 females (44.8%); their mean age was 71.3. The mean duration of diabetes mellitus was 13 years (3-20). 19 patients (65.5%) were treated with insulin, 10 patients (34.4%) were treated with peroral antidiabetics (PAD); the mean HbA1c value was 52 mmol/l. The treatment was started with 3 initial doses of intravitreal injections of Ranibizumab 0.5 mg. There was a one- -month interval between the applications. Subsequent evaluations and administrations of the following injections were made in the pro re nata (PRN) mode; the check-ups were carried out every month during the first year and on average every 3 months in the second year. The monitored parameters: the best corrected visual acuity (BCVA) measured on ETRDS (Early Treatment Diabetic Retinopathy Study) optotypes, the central retinal thickness (CRT). These parameters were monitored prior to the treatment and then in the 3rd, 6th, 9th, 12th, 18th and 24th months.

RESULTS

A statistically significant improvement in the mean value of BCVA was detected. From the initial 65.4 ±10.61 letters it improved by 11.2 letters (p.

Diabetic Retinopathy and Diabetic Macular Edema in People With Early-Onset Diabetes

This study examined the clinical profile, treatment profile, and vision outcomes of people ≤40 years of age with diabetes and diabetic macular edema (DME). Within this age-group, the prevalence of center-involving DME was 16%, with 74% of eyes showing cystoid edema, 37% showing spongiform edema, and 41% having neurosensory detachment. Longer diabetes duration (P = 0.001) and greater severity of diabetic retinopathy (P <0.001) were associated with DME prevalence. Thus, regular and more frequent follow-up, as well as early and aggressive treatment of diabetic eye disease, are required in people diagnosed early with diabetes.

Changes of plasma nitric oxide, endothelin-1, and blood coagulation following intravitreal conbercept

Intravitreal anti-VEGF (anti-vascular endothelial growth factor) biologics have revolutionized the pharmacological management of chorioretinal diseases. However, the systemic adverse events such as stroke or bleeding are the concerns for many patients and physicians. The mechanism to develop these side effects are poorly understood. Consecutive 95 patients with retinal diseases were studied for their blood activated partial thromboplastin time (APTT), prothrombin time (PT), international normalized ratio (INR), and concentration of fibrinogen before and after intravitreal conbercept. Additionally, plasma nitric oxide (NO) and endothelin-1 (ET-1) were investigated on 38 of the 95 patients. Compared with the pre-injection, 4-week post-injection values of APTT and PT were increased by 0.582 s (p = 0.038, paired t test) and by 0.086 s (p = 0.080, paired t test; p = 0.0475, Sign test), respectively. At the same time, fibrinogen decreased by 0.048 g/L. Plasma levels of NO or ET-1 or VEGF did not significantly change from pre-injection levels. Our findings advanced the understanding of mechanism for systemic side effects associated with intravitreal anti-VEGF and emphasized paying more attention to higher risk of possible bleedings for patients following intravitreal conbercept.

Race and Socioeconomic Status in Anti-VEGF Treatment of Diabetic Macular Edema

BACKGROUND AND OBJECTIVE

Although people of low socioeconomic status (SES) and certain racial groups are at greater risk of developing diabetic macular edema (DME), the extent these high-risk groups experience treatment differences is unknown. This study characterizes anti-vascular endothelial growth factor (anti-VEGF) injection use for DME.

PATIENTS AND METHODS

Data were collected from an electronic health record at the Cole Eye Institute, Cleveland Clinic Foundation for patients who received anti-VEGF treatment for DME between 2012 and 2019 (N = 500).

RESULTS

White patients on average received more injections over a 1-year period than Black patients (4.93 ± 3.14 vs 3.20 ± 2.43; P < .0001) and had fewer no-show appointments (1.39 ± 2.08 vs 3.23 ± 3.39; P < .0001). There is an association between living in communities with lower average incomes and receiving fewer anti-VEGF injections (3.06 ± 2.70 vs 4.88 ± 3.19; P = .005).

CONCLUSIONS

DME treatment differs based on race and SES. Racial and SES associations with anti-VEGF injections present potential obstacles for delivering optimal ophthalmic care. [Ophthalmic Surg Lasers Imaging Retina. 2021;52:578-585.].

Correlation of response to intravitreal bevacizumab treatment between the first and second treated eyes in diabetic macular edema

PURPOSE

To evaluate whether outcome of bevacizumab treatment in the first treated eye can guide the selection of compound for the second treated eye in patients with bilateral diabetic macular edema.

METHODS

Demographic, clinical, and optical coherence tomography data were retrospectively collected from consecutive patients who underwent bevacizumab therapy for bilateral diabetic macular edema. Change in central subfield thickness and visual acuity were evaluated and compared between the first treated eye and second treated eye.

RESULTS

A total of 66 eyes of 33 patients were included in the study. The mean ± SD follow-up time was 13 ± 5 months. The mean ± SD central subfield thickness at baseline was 464 ± 30 μm in the first treated eye and 461 ± 29 μm in the second treated eye (p = 0.91). Final central subfield thickness was reduced to 392 ± 27 μm in the first treated eye (p = 0.01 compared with baseline) and 416 ± 25 μm in the second treated eye (p = 0.03 compared with baseline). Using ≥5% or ≥10% reduction of central subfield thickness as diagnostic criteria to predict similar magnitude of thickness reduction in the first treated eye yielded a positive and negative predictive value ranging from 46% to 81%, and sensitivity and specificity ranging from 54% to 84%. Regression models did not show correlation between central subfield thickness reduction in first treated eye and the second treated eye at the end of follow-up.

CONCLUSIONS

Bevacizumab therapy reduced macular thickness in both eyes in bilateral diabetic macular edema. Treatment outcome of the first treated eye could not predict the outcome of the second treated eye. Particularly, failure to reduce central subfield thickness in the first treated eye does not preclude a favorable response to bevacizumab therapy in the second eye.

Comparison Between Ranibizumab Biosimilar, Innovator Ranibizumab and Bevacizumab in a Real-World Situation

Introduction

To analyze the efficacy of biosimilar ranibizumab compared to innovator ranibizumab and bevacizumab.

Methods

We retrospectively analyzed consecutive patients treated with biosimilar ranibizumab for wet age-related macular degeneration (AMD) and macular edema (ME) (due to diabetes and vein occlusion) and compared them with ranibizumab- and bevacizumab-treated patients.

Results

Of 202 patients, 67 (33.2%) received biosimilar ranibizumab (BSR), 69 (34.2%) ranibizumab (RBZ) and 66 (32.7%) bevacizumab (BEV). All patients received three consecutive injections followed by pro re nata dosing. The follow-up ranged from 3 to 24 months. The mean numbers of injections were 6.68 for RBZ, 6.4 for BEV and 4.7 for BSR. At 3 months, nAMD (n = 115, 56.9%) and ME (n = 87, 43.1%) groups showed significant improvement in vision and central foveal thickness (CFT) across all three agents. After ≥ 6 months, the effects were maintained in the AMD group but not in the ME group. Maximum effect was seen at 1 month. At no point in time was a significant difference noted among the three anti-vascular endothelial growth factor (anti-VEGF) agents. No major safety concerns were noted.

Conclusions

Biosimilar ranibizumab is comparable to innovator ranibizumab and bevacizumab in efficacy and safety.

Updates on the Current Treatments for Diabetic Retinopathy and Possibility of Future Oral Therapy

Diabetic retinopathy (DR) is a complication of diabetes and one of the leading causes of vision loss worldwide. Despite extensive efforts to reduce visual impairment, the prevalence of DR is still increasing. The initial pathophysiology of DR includes damage to vascular endothelial cells and loss of pericytes. Ensuing hypoxic responses trigger the expression of vascular endothelial growth factor (VEGF) and other pro-angiogenic factors. At present, the most effective treatment for DR and diabetic macular edema (DME) is the control of blood glucose levels. More advanced cases require laser, anti-VEGF therapy, steroid, and vitrectomy. Pan-retinal photocoagulation for non-proliferative diabetic retinopathy (NPDR) is well established and has demonstrated promising outcomes for preventing the progressive stage of DR. Furthermore, the efficacy of laser therapies such as grid and subthreshold diode laser micropulse photocoagulation (SDM) for DME has been reported. Vitrectomy has been performed for vitreous hemorrhage and tractional retinal detachment for patients with PDR. In addition, anti-VEGF treatment has been widely used for DME, and recently its potential to prevent the progression of PDR has been remarked. Even with these treatments, many patients with DR lose their vision and suffer from potential side effects. Thus, we need alternative treatments to address these limitations. In recent years, the relationship between DR, lipid metabolism, and inflammation has been featured. Research in diabetic animal models points to peroxisome proliferator-activated receptor alpha (PPARα) activation in cellular metabolism and inflammation by oral fenofibrate and/or pemafibrate as a promising target for DR. In this paper, we review the status of existing therapies, summarize PPARα activation therapies for DR, and discuss their potentials as promising DR treatments.