Diabetic macular edema: current and emerging therapies

Cost-Effectiveness of Faricimab in the Treatment of Diabetic Macular Oedema (DMO): A UK Analysis

AIM

The aim of this work was to evaluate the cost-effectiveness of faricimab against relevant therapeutic alternatives used in clinical practice for the treatment of diabetic macular oedema (DMO) in the UK.

METHODS

A state-transition (Markov) model, with health states based on visual acuity scores and treatment pathways, was developed to conduct cost-utility analysis of faricimab treat and extend (T&E) regimen versus ranibizumab pro re nata (PRN) and aflibercept PRN over a time horizon of 25 years. Comparison against bevacizumab PRN was considered in scenario analysis. Effectiveness data for faricimab was sourced from the pivotal YOSEMITE and RHINE double-blind randomised controlled trials, and from a network meta-analysis for comparators. Costs and (dis)utilities were taken from nationally published sources or literature. The base case included indirect costs (productivity gains, informal care) given the wider impacts of DMO on society. Sensitivity analyses were conducted.

RESULTS

In the base case, faricimab T&E dominated ranibizumab PRN and aflibercept PRN, being more effective and resulting in cost savings (between 0.16 and 0.36 mean QALYs gained, and £5483-9655 mean cost savings). In scenario analysis, faricimab was more effective but costlier compared with bevacizumab, with an incremental cost-effectiveness ratio (ICER) of £8898 per QALY gained. Considering only healthcare payer costs, the ICER of faricimab compared with ranibizumab PRN was £7991 per QALY gained and faricimab dominated aflibercept PRN.

CONCLUSIONS

Faricimab T&E has the potential to reduce the burden of vision loss on society, giving people living with DMO greater independence and contributing to increased healthcare system capacity. At a threshold of £20,000, faricimab T&E is cost-effective compared with relevant comparators, and potentially cost saving.

Recommendations for diabetic macular edema management by retina specialists and large language model-based artificial intelligence platforms

PURPOSE

To study the role of artificial intelligence (AI) in developing diabetic macular edema (DME) management recommendations by creating and comparing responses to clinicians in hypothetical AI-generated case scenarios. The study also examined whether its joint recommendations followed national DME management guidelines.

METHODS

The AI hypothetically generated 50 ocular case scenarios from 25 patients using keywords like age, gender, type, duration and control of diabetes, visual acuity, lens status, retinopathy stage, coexisting ocular and systemic co-morbidities, and DME-related retinal imaging findings. For DME and ocular co-morbidity management, we calculated inter-rater agreements (kappa analysis) separately for clinician responses, AI-platforms, and the "majority clinician response" (the maximum number of identical clinician responses) and "majority AI-platform" (the maximum number of identical AI responses). Treatment recommendations for various situations were compared to the Indian national guidelines.

RESULTS

For DME management, clinicians (ĸ=0.6), AI platforms (ĸ=0.58), and the 'majority clinician response' and 'majority AI response' (ĸ=0.69) had moderate to substantial inter-rate agreement. The study showed fair to substantial agreement for ocular co-morbidity management between clinicians (ĸ=0.8), AI platforms (ĸ=0.36), and the 'majority clinician response' and 'majority AI response' (ĸ=0.49). Many of the current study's recommendations and national clinical guidelines agreed and disagreed. When treating center-involving DME with very good visual acuity, lattice degeneration, renal disease, anaemia, and a recent history of cardiovascular disease, there were clear disagreements.

CONCLUSION

For the first time, this study recommends DME management using large language model-based generative AI. The study's findings could guide in revising the global DME management guidelines.

Comparative Efficacy, Durability and Safety of Faricimab in the Treatment of Diabetic Macular Edema: A Systematic Literature Review and Network Meta-Analysis

INTRODUCTION

A systematic literature review (SLR) and network meta-analysis (NMA) were conducted to evaluate the comparative efficacy, durability and safety of faricimab, used in a Treat & Extend (T&E) regime with intervals up to every 16 weeks (Q16W), relative to other therapies currently in use for treatment of diabetic macular oedema (DME). Of particular interest were anti-vascular endothelial growth factor (VEGF) therapies applied in flexible dosing regimens such as Pro re nata (PRN) and T&E, which are the mainstay in clinical practice.

METHODS

An SLR identifying randomised controlled trials (RCTs) published before August 2021 was conducted, followed by a Bayesian NMA comparing faricimab T&E treatment to aflibercept, ranibizumab, bevacizumab, dexamethasone and laser therapy. Outcomes included in the analysis were change in best-corrected visual acuity (BCVA), change in central subfield thickness (CST), injection frequency, ocular adverse events (AE) and all-cause discontinuation, all of which were evaluated at 12 months. Subgroup analyses including patients' naïve to anti-VEGF were conducted where feasible.

RESULTS

Twenty-six studies identified in the SLR were included in the NMA. Most importantly for decision making in clinical practise, faricimab T&E was associated with a statistically greater (95% credible intervals exclude zero) and clinically meaningful decrease in retinal thickness compared to all other flexible dosing regimens (greater retinal drying by 55-125 microns). Anatomical outcomes determine treatment efficacy and retreatment of patients. The NMA also showed a statistically greater increase in mean change in BCVA for faricimab T&E vs. flexible regimens using ranibizumab and bevacizumab (increase of 4.4-4.8 letters) as well as a numerical improvement vs. aflibercept PRN (two letters, 95% credible intervals including zero). Accordingly, the injection frequency was numerically lower versus other treatments using flexible dosing regimens (decrease by 0.92-1.43 injections). The analyses also indicated that the safety profile of faricimab T&E was comparable to those of ranibizumab and aflibercept, which have well-established safety profiles, with similar results for the number of all-cause discontinuations.

CONCLUSION

Faricimab provides a new treatment option in DME with dual-pathway inhibition of VEGF and angiopoeitin-2 (Ang-2). To the authors' knowledge, this is the first indirect comparison of faricimab T&E in DME. The analyses indicate that faricimab T&E is associated with superior retinal drying along with numerically fewer injections compared to all other treatments given in flexible dosing regimens. It also showed superior visual acuity outcomes compared to ranibizumab and bevacizumab.

Determination of Factors Influencing the Health Belief Model (HBM) and Adherence to Intravitreal Anti-vascular Endothelial Growth Factor (VEGF) Among Patients With Diabetic Macular Edema (DME)

Background Diabetic macular edema (DME) is becoming one of the leading causes of blindness worldwide with a significant impact on quality of life. The effectiveness of intravitreal (IVT) anti-vascular endothelial growth factor (VEGF) therapy has been established by clinical trials and has become the treatment of choice in the majority of DME patients in reducing macular edema and improving visual acuity. Frequent drop-out and discontinuation of treatment are major issues. Lack of compliance can lead to worsening outcomes and be a burden to patients and the healthcare system. Purpose The purpose of this study is to assess multiple factors that affect adherence to IVT anti-VEGF treatment among patients with DME, including socioeconomic causes and the Health Belief Model (HBM) domains, in addition to exploring the relationship between them. Methods This cross-sectional study was conducted among DME patients in Hospital Canselor Tuanku Muhriz, Kuala Lumpur, Malaysia, from December 2020 to June 2021. We identified eligible patients using a retrospective chart review of clinical findings and optical coherence tomography (OCT) findings. Included subjects were of Malaysian nationality, aged 18 years and above, who were initiated or re-initiated IVT anti-VEGF treatment regime and on follow-up for at least six months from initial injection from January 2019 onwards. A translated and validated self-administered questionnaire was given to the respondents. Data were analyzed using IBM SPSS Statistics for Windows, Version 26.0 (Released 2019; IBM Corp., Armonk, New York, United States). Demographics of the patient were summarized using descriptive statistics, independent sample t-test was used to compare the difference in components of the HBM questionnaire. Linear regression was further used to explore the relationship between patients' demographics and the HBM component. Results A total of 141 patients participated in this study, of whom 56.2% patients were adherent to treatment. The majority were aged 60 years and above (56.7%), male (52.5%), Malay (38.9%), and married (71.6%). There was a significant statistical difference in patients who were adherent to treatment, in terms of life entourage (p=0.004, Fisher Exact test). HBM domains that influenced adherence to treatment included perceived severity, perceived barriers, perceived benefits, cues to action, and self-efficacy (p<0.05, independent sample t-test). Further, multiple logistic regression tests on sociodemographic factors and HBM domains after eliminating confounding factors narrowed down the significant variables to perceived susceptibility (p= 0.023), perceived benefits (p< 0.001), and self-efficacy (p< 0.001). Conclusion Patients' adherence to IVT anti-VEGF is influenced by perceived susceptibility to complications from DME, perceived benefits to the treatment, and self-efficacy.

Impact of retinal fluid in patients with diabetic macular edema treated with anti-vascular endothelial growth factors in routine clinical practice

OBJECTIVE

This study aims to determine the effect of intraretinal (IRF) and subretinal (SRF) fluid on visual outcomes for diabetic macular edema (DME) patients treated with anti-vascular endothelial growth factor (anti-VEGF) in routine clinical practice.

DESIGN

Optical coherence tomography scans were analyzed with a deep-learning artificial intelligence software to quantify IRF, SRF, and total retinal fluid (TRF) at baseline and at 3, 6, and 12 months. Predictive variables for best-corrected visual acuity (BCVA) were evaluated with linear mixed-effects regression models.

PARTICIPANTS

A total of 220 DME eyes of 220 patients from the Cole Eye Institute at Cleveland Clinic.

METHODS

Retrospective, nonrandomized cohort study.

RESULTS

BCVA improved from baseline to 12 months (63.36 ± 14.72 to 68.49 ± 13.14 Early Treatment Diabetic Retinopathy Study letters, p < 0.001, respectively). Central subfield thickness improved from baseline to 12 months (411.74 ± 129.7 to 335.94 ± 116.91 mm, p < 0.001, respectively). Injection frequency per patient was 8.25 ± 2.5 injections over 12 months. The linear mixed-effects regression model in the foveal region for TRF, IRF, and SRF volume at the fourth quartile showed BCVA losses of -8.29 letters (range, -10.96 to -5.62 letters, p < 0.001), -7.52 letters (range, -10.3 to -4.74 letters, p < .001), and -6.93 letters (range, -10.54 to -3.41 letters, p < .001), respectively.

CONCLUSIONS

The highest quartile of TRF, IRF, and SRF volumes led to worse visual outcomes after 12 months of anti-VEGF treatment in patients with DME. Further studies designed to investigate the effect of anti-VEGF treatment on retinal fluid morphology could provide greater insight into individualized DME treatment.

Treatment patterns and persistence rates with anti-vascular endothelial growth factor treatment for diabetic macular oedema in the UK: A real-world study

INTRODUCTION

Anti-vascular endothelial growth factors (anti-VEGFs) are considered standard of care therapy for diabetic macular oedema (DME). This study examined treatment patterns and outcomes in patients with DME treated with anti-VEGF therapy.

METHODS

Using anonymized electronic medical record data collected from three UK sites, this retrospective cohort study assessed rates of anti-VEGF intravitreal injections in adults with treatment-naïve DME who received their first treatment between 1 September 2010 and 31 July 2018. The proportion of patients with at least one interval of at least 12 weeks between injections; the distribution of injection intervals; the discontinuation rates; and the number of anti-VEGF injection-, injection-free- and total visits were assessed during the first and second years of treatment.

RESULTS

Overall, 1606 patient eyes with DME were included, with no minimum follow-up. During the first and second year of treatment, 63.2% and 73.1% of eyes had at least one anti-VEGF injection interval of at least 12 weeks, respectively. In the first and second years of treatment, the mean (standard deviation) numbers of injections were 7.7 (1.9) and 5.6 (2.2), with 14.2 (5.7) and 13.4 (6.4) total clinic visits, and 6.6 (5.0) and 7.8 (5.8) injection-free visits, respectively. In total, 27.8% of patient eyes discontinued treatment during the first 2 years.

CONCLUSIONS

The high number of clinic visits and high discontinuation rates demonstrate a significant unmet need for a treatment to enable sustainable extended injection intervals, while maintaining visual acuity. This could improve patient adherence and health-related quality of life for patients with DME.

V, Josephraj AN, E. S. Diagnosis of retinal disorders from Optical Coherence Tomography images using CNN

An efficient automatic decision support system for detection of retinal disorders is important and is the need of the hour. Optical Coherence Tomography (OCT) is the current imaging modality for the early detection of retinal disorders non-invasively. In this work, a Convolution Neural Network (CNN) model is proposed to classify three types of retinal disorders namely: Choroidal neovascularization (CNV), Drusen macular degeneration (DMD) and Diabetic macular edema (DME). The hyperparameters of the model like batch size, number of epochs, dropout rate, and the type of optimizer are tuned using random search optimization method for better performance to classify different retinal disorders. The proposed architecture provides an accuracy of 97.01%, sensitivity of 93.43%, and 98.07% specificity and it outperformed other existing models, when compared. The proposed model can be used for the large-scale screening of retinal disorders effectively.

Significance of monitoring vascular endothelial growth factor, monocyte chemoattractant protein-1 and Interleukin-8 in diabetic macular edema towards early identification of nonresponders to ranibizumab therapy

Purpose:

Identification of nonresponders prior to anti-vascular endothelial growth factor (anti-VEGF) therapy would help in the judicious clinical management of diabetic macular edema (DME) patients. Thus, a systematic study was initiated to identify nonresponding DME patient population undergoing ranibizumab treatment to figure out additional inflammatory components that may contribute to their nonresponsiveness to anti-VEGF therapy.

Methods:

A total of 40 patients recruited to this investigator-initiated trial received intravitreal ranibizumab monthly for 3 months. The fourth- and fifth-month injections were according to PRN protocol and the sixth-month injection was mandatory. Best-corrected visual acuity (BCVA), central macular thickness (CMT), and VEGF in aqueous humor were measured for all the patients. Patients were grouped into responders/nonresponders on the formulated criteria and the levels of key pro-inflammatory cytokines were also measured between the two groups at baseline, 2 month and 5 months using cytometric bead array (CBA).

Results:

Eleven patients were categorized (29.72%) as responders and 10 patients (27.02%) as nonresponders. Nonresponders showed poorer BCVA (P = 0.024, 0.045, and 0.048 for 4, 5, and 6 months) and higher CMT (P = 0.021, 0.0008 and <0.0001 for baseline, 1, 2, 3, 4, 5, and 6 months) compared to responders. The cytokines IL-8, MCP-1 were significantly up regulated (P = 0.0048 and 0.029 for MCP-1 and IL-8) in nonresponders.

Conclusion:

Elevated MCP-1 and IL-8 levels found in the nonresponders could be used as a prognostic marker to identify these groups of patients and can help in developing alternative treatment options along with anti-VEGF therapy.

EVALUATION OF THE EFFECT OF TOPICAL INTERFERON α2b AS A COMPLEMENTARY TREATMENT OF MACULAR EDEMA OF PATIENTS WITH DIABETIC RETINOPATHY: A Double-Blind Placebo-Controlled Randomized Clinical Trial Study

PURPOSE

The objective of this study is to evaluate the effect of the topical interferon α2b (IFNα2b) as an adjunctive therapy in the treatment of diabetic macular edema.

METHOD

This was a randomized controlled clinical trial performed on patients with diabetic macular edema. Fifty eyes of 50 patients (one eye/patient) who were receiving treatment for diabetic macular edema were randomly assigned to get topical IFNα2b 1 MU/mL or artificial tear eye drop as an adjunctive therapy. The primary measure outcomes were best-corrected visual acuity and central macular thickness; the secondary goals were to assess the effect of topical IFNα2b on the intraocular pressure and its potential side effects.

RESULTS

Baseline demographic data of the two groups were similar. The improvement in visual acuity of patients on IFN was more than the patients on artificial tear by the end of the fourth week (6.85 and 1.45 Early Treatment Diabetic Retinopathy Study letters, respectively, P = 0.001) and the eighth week (6.75 and 1.05 Early Treatment Diabetic Retinopathy Study letters, respectively, P = 0.005). The central macular thickness was also decreased correspondingly by the end of fourth week (53.1 ± 153 µm for patients on IFN and 26.6 ± 119.1 µm for patients on artificial tear, P = 0.497) and eighth week (27.9 ± 67.7 for patients on IFN and 29.2 ± 98 µm for patients on artificial tear, P = 0.957), but it was not statistically significant. Intraocular pressure was decreased on the fourth week in IFN group for 1.7 mmHg ±3 and increased for 0.1 mmHg ±2.3 in the artificial tear group (P = 0.018). No significant side effect was detected with topical IFN drop.

CONCLUSION

This study evaluated the short-term effects of topical IFNα2b 1 MU/mL. The drug was well tolerated and may have an effect on improvement of best-corrected visual acuity in patients with diabetic macular edema. It also had an intraocular pressure lowering effect on the studied eyes. However, further studies are needed to confirm this finding.

Comparing vision and macular thickness in neovascular age-related macular degeneration, diabetic macular oedema and retinal vein occlusion patients treated with intravitreal antivascular endothelial growth factor injections in clinical practice

Objective

To compare the visual outcomes of intravitreal antivascular endothelial growth factor (anti-VEGF) injections in neovascular age-related macular degeneration (nAMD), diabetic macular oedema (DMO) and retinal vein occlusion (RVO) in a real-world setting.

Methods and analysis

Retrospective analysis of data from the Tasmanian Ophthalmic Biobank database. The median change in best-corrected visual acuity (BCVA) between baseline and 12 months post initiating intravitreal anti-VEGF treatment were compared between the three diseases. Final BCVA, central macular thickness (CMT), cumulative number of injections and overall predictors of change in BCVA and CMT were also determined.

Results

At 12 months, change in BCVA was significantly different between nAMD, DMO and RVO cohorts (p=0.032), with lower median change for DMO (2 letters, range −5 to 20) than for RVO (11 letters, range −20 to 35). Likewise, CMT change was significantly different between the three cohorts (p=0.022), with a smaller reduction in CMT in DMO (−54 µm, range −482 to 50) than RVO patients (−137 µm, range −478 to 43; p=0.033). Total number of injections received (p=0.028) and final BCVA score (p=0.024) were also significantly different between the groups. Baseline BCVA was a negative predictor (p=0.042) and baseline CMT a positive predictor (p<0.001) of outcome. After adjusting for baseline BCVA and CMT, diagnosis of nAMD or RVO was a predictor of visual improvement compared with the DMO.

Conclusions

At the end of 12 months, nAMD and RVO cohorts had the greatest improvement in BCVA, however the final BCVA for DMO was significantly better than for nAMD.

A study of therapeutic effects of 670 nm irradiation in different types of diabetic macular edema

The purpose of this study was to investigate the therapeutic effects of 670 nm irradiation in patients with diabetic macular edema. In several studies, positive effects of red/near-infrared irradiation showed in a range of ocular diseases such as macular degeneration, macular edema, and retinitis pigmentosa. This study was conducted on forty five eyes of 26 diabetic patients with macular edema between the ages of 51 and 80.

Measurement of visual acuity and slit lamp examination, funduscopy, and optical coherence tomography were performed in all subjects. None of the patients had proliferative retinopathy. We used a portable LED device (Warp 10, Quantum Devices) for treatment. Patients held this device at a distance of 3 cm from their eyes for 240 seconds for three months. Full ophthalmic examinations were repeated 1, 2, and 3 months after treatment.

After 3 months, the mean visual acuity improved from 0.44 ± 0.38 log MAR to 0.27 ± 0.24 log MAR and vision increased by 1.52 ± 1.16 lines post treatment (р<0.001). The mean central macula thickness decreased from 381.49 ± 144.40 μm to 359.72 ± 128.84 μm (р=0.050). In patients with mild and moderate nonproliferative diabetic retinopathy, the mean central retinal thickness decreased 52.06 ± 67.78 μm and 39.27 ± 44.69 μm, respectively, but patients with severe type showed an increase of 34.93 ± 65.65 μm in the mean central retinal thickness (р<0.001). Also, the severity of macular edema had no effect on final outcomes (р>0.05). Photobiomodulation can positively affect diabetic macular edema, especially in patients with mild to moderate diabetic retinopathy.

The USER Study: A Chart Review of Patients Receiving a 0.2 µg/day Fluocinolone Acetonide Implant for Diabetic Macular Edema

Introduction

To determine anatomical, functional, and intraocular pressure (IOP) responses to diabetic macular edema (DME) treatments pre- and post-0.2 µg/day fluocinolone acetonide (FAc) implant administration compared with baseline and the preceding 3 years.

Methods

This was a retrospective, chart review, cohort study in four U.S. centers. Patients received the 0.2 µg/day FAc implant for the treatment of DME in at least one eye before January 1, 2016. DME treatments administered up to 36 months pre-FAc implant and up to 24 months post-FAc implant were recorded, and treatment frequency was calculated. Visual acuity (VA) was assessed using a Snellen eye chart and converted to early treatment diabetic retinopathy study (ETDRS) letters, and central subfield thickness (CST) was measured using optical coherence tomography (OCT). Treatment frequency, mean VA, mean CST, percentage of patients with CST of ≤ 300 µm, mean IOP, IOP events, and IOP treatments pre- and post-FAc implant administration were measured. Positive and negative predictive values for the IOP response to prior steroid therapy were also determined.

Results

In total, 160 eyes of 130 patients were studied. VA was maintained at pre-FAc levels from baseline to month 24, despite a significant reduction in treatment frequency from one treatment every 2.9 months pre-FAc implant to one treatment every 14.3 months post-FAc implant. Patients with better baseline VA required fewer DME treatments post-FAc than did patients with worse baseline VA. The majority of patients did not require additional DME treatment during the post-FAc follow-up period. A significant reduction in CST and an increase in the percentage of patients with CST of ≤ 300 µm were seen up to month 21 post-FAc implant. Pre-FAc implant IOP was maintained during the post-FAc implant period; increased IOP with prior steroid therapy was found to be highly predictive of increased IOP post-FAc implant.

Conclusion

The results of this study confirm the positive safety and efficacy profile of the FAc implant and demonstrate for the first time the effectiveness of the U.S. label indication of FAc in reducing the incidence of post-treatment pressure elevation. The FAc implant significantly reduced treatment burden in the overall population without significantly increasing the risk of steroid-induced pressure elevation.

Funding

Alimera Sciences.

CLINICAL EVIDENCE OF THE MULTIFACTORIAL NATURE OF DIABETIC MACULAR EDEMA

As the disease duration increases, the multifactorial nature of diabetic macular edema becomes more prominent, and corticosteroid therapy represents an important treatment option for patients whose disease is multifactorial.

Purpose:

To report functional and morphologic outcomes, based on diabetic macular edema (DME) chronicity and baseline best-corrected visual acuity (BCVA), from a subanalysis of the fluocinolone acetonide for macular edema (FAME) trials.

Methods:

Patients were categorized by DME duration (nonchronic [ncDME] or chronic [cDME] DME) and three nonexclusive baseline vision strata. Anatomic and visual acuity VA outcomes of these cohorts were compared with treatment assignment.

Results:

For all patients with ncDME and cDME who received sham control, 27.8% and 13.4%, respectively, gained ≥15 BCVA letters, whereas 22.3% and 34.0% of 0.2 μg/day fluocinolone acetonide (FAc)-treated patients, respectively, gained ≥15 BCVA letters. Among patients with ncDME who received sham control, as baseline vision decreased, the percentage gaining ≥15 BCVA letters increased; however, among those with cDME, the percentage gaining ≥15 BCVA letters did not change as baseline vision decreased. Conversely, among 0.2 μg/day FAc-treated patients, the percentage gaining ≥15 BCVA letters increased with decreasing baseline vision, regardless of DME chronicity. Anatomical outcomes were similar within treatment arms, regardless of the DME duration.

Conclusion:

Patients with cDME and poor baseline vision who were exposed to low-dose FAc experienced BCVA improvements that were not observed in a similar group from the sham-control arm. These data support the multifactorial pathogenesis of cDME.

Efficiency of fenofibrate in facilitating the reduction of central macular thickness in diabetic macular edema

PURPOSE

The purpose of this study is to study the benefit of addition of oral fenofibrate to the current regimen of diabetic macular edema (DME) management and quantify its effect on macular thickness and visual function in DME.

METHODS

Fifty-three eyes of 50 patients were randomized into treatment (Group A) (oral fenofibrate 160 mg/day) and control groups (Group B). Both groups underwent treatment of DME as per the standard treatment protocol of our hospital including intravitreal injections (anti-vascular endothelial growth factor/steroid) and grid laser. Patients were followed up every 2 months to note the visual acuity and central macular thickness (CMT) for 6 months.

RESULTS

Our groups were matched with respect to age (P = 0.802), mean diabetic age (P = 0.878), serum HbA1C levels (P = 0.523), and serum triglyceride levels (P = 0.793). The mean reduction in CMT was 136 μ in Group A and 83 μ in Group B at the end of 6 months. This difference was statistically significant (P = 0.031). Visual acuity improvement was 0.15 in Group A and 0.11 in Group B at the end of 6 months (P = 0.186). On subgroup analysis in Group A, we found that there was no difference in reduction of CMT between hypertensives and normotensives (P = 0.916), in patients with normal triglyceride levels and increased triglyceride levels (P = 0.975).

CONCLUSION

Addition of fenofibrate to the standard protocol of DME management seems to facilitate reduction of CMT and probably have an added benefit on the visual functions.

Real-Life ILUVIEN (Fluocinolone Acetonide) Case Study: Rapid Drying of the Macula and Improved Vision within 2 Years after Therapy Initiation

IMPORTANCE

A case showing sustained structural and functional responses 2 years after a single treatment with ILUVIEN (0.2 µg/day fluocinolone acetonide, FAc) despite suboptimal responses to ranibizumab.

OBSERVATIONS

A 68-year-old female patient with diabetic macular oedema (DME) from type 2 diabetes mellitus was first diagnosed in October 2010 and had a baseline visual acuity (VA) of 46 Early Treatment Diabetic Retinopathy Study (ETDRS) letters in the left eye. Central foveal thickness (CFT) was 712 microns. The patient was treated with 11 intravitreal injections of ranibizumab (5 in combination with a small-interfering RNA agent), and by March 2014, VA and CFT were largely unchanged (55 ETDRS letters and 774 microns). The patient was treated with ILUVIEN as she had a pseudophakic lens and a clearly suboptimal response to the prior therapy with ranibizumab. An implant releasing FAc at a dosage of 0.2 µg/day was administered in March 2014, and the optical coherence tomography indicated that the macula was dry after 7 days (CFT was below 300 microns). This was sustained at 6, 12, and 24 months after the treatment. VA improved by 5 letters within 7 days and by 15 letters within 14 days, and this was maintained after 24 months. Throughout the duration of this study, the intraocular pressure was ≤22 mm Hg, and no glaucoma medication was administered.

CONCLUSIONS AND RELEVANCE

In real-life UK practice, this DME patient showed a suboptimal response to multiple intravitreal injections of ranibizumab. When subsequently treated with a single injection of ILUVIEN, there were large and rapid improvements in VA and CFT that were maintained for the following 2 years.

Forming a Consensus: Data and Guidance for Physicians Treating Diabetic Macular Edema

The diabetic macular edema (DME) treatment paradigm has evolved as the understanding of the disease pathology has grown. Since 2012, four pharmacotherapies have been approved by the U.S. Food and Drug Administration for the treatment of DME. First-line treatment of DME with anti-vascular endothelial growth factor [VEGF] agents has become the gold standard; however, an appreciable percentage of patients do not respond to anti-VEGF therapies. In patients who inadequately respond to anti-VEGF therapies, the underlying disease pathology may be mediated by a multitude of growth factors and inflammatory cytokines. For these patients, corticosteroids are an attractive treatment option because they not only downregulate VEGF, but also an array of cytokines. The phase 3 MEAD and FAME trials demonstrated significant visual acuity improvements associated with dexamethasone and fluocinolone acetonide, respectively, in patients with DME; however, class-specific adverse events, including increased intraocular pressure and cataract development, must be considered before use. A panel of experts gathered during the 2015 annual meeting of the American Academy of Ophthalmology for a roundtable discussion focused on patient selection and adverse event management associated with the use of the 0.19 mg fluocinolone acetonide intravitreal implant.

Rethinking Nuclear Receptors as Potential Therapeutic Targets for Retinal Diseases

Collectively, retinal diseases, including age-related macular degeneration, retinitis pigmentosa, and diabetic retinopathy, result in severe vision impairment worldwide. The absence and/or limited availability of successful drug therapies for these blinding disorders necessitates further understanding their pathobiology and identifying new targetable signaling pathways. Nuclear receptors are transcription regulators of many key aspects of human physiology, as well as pathophysiology, with reported roles in development, aging, and disease. Some of the pathways regulated by nuclear receptors include, but are not limited to, angiogenesis, inflammation, and lipid metabolic dysregulation, mechanisms also important in the initiation and development of several retinal diseases. Herein, we present an overview of the biology of three diseases affecting the posterior eye, summarize a growing body of evidence that suggests direct or indirect involvement of nuclear receptors in disease progression, and discuss the therapeutic potential of targeting nuclear receptors for treatment.

Novel strategies for the treatment of diabetic macular edema

Macular edema such as diabetic macular edema (DME) and diabetic retinopathy are devastating back-of-the-eye retinal diseases leading to loss of vision. This area is receiving considerable medical attention. Posterior ocular diseases are challenging to treat due to complex ocular physiology and barrier properties. Major ocular barriers are static (corneal epithelium, corneal stroma, and blood-aqueous barrier) and dynamic barriers (blood-retinal barrier, conjunctival blood flow, lymph flow, and tear drainage). Moreover, metabolic barriers impede posterior ocular drug delivery and treatment. To overcome such barriers and treat back-of-the-eye diseases, several strategies have been recently developed which include vitreal drainage, laser photocoagulation and treatment with biologics and/or small molecule drugs. In this article, we have provided an overview of several emerging novel strategies including nanotechnology based drug delivery approach for posterior ocular drug delivery and treatment with an emphasis on DME.

A randomized clinical trial comparing fixed vs pro-re-nata dosing of Ozurdex in refractory diabetic macular oedema (OZDRY study)

OBJECTIVE

To compare the clinical effectiveness and safety of 5-monthly fixed dosing vs pro-re-nata (PRN) Ozurdex treatment in patients with refractory diabetic macular oedema (DMO).

DESIGN

Prospective, multicentre, randomized active-controlled non-inferiority clinical trial.

PARTICIPANTS

Participants were 100 patients who attended Medical Retina Clinics for management of centre-involving refractory DMO.

INTERVENTIONS

Participants were randomized 1 : 1 to either 5-monthly fixed dosing or optical coherence tomography (OCT)-guided PRN regimen of Ozurdex therapy for DMO. Data were collected on best-corrected visual acuity (BCVA), patient-reported outcome measures (PROM), macular thickness and morphology, diabetic retinopathy status, number of injections and adverse events from baseline for a period of 12 months.Main outcome measuresThe primary outcome was the difference between arms in change in BCVA from baseline to 12 months. The prespecified non-inferiority margin was five ETDRS letters. Key secondary outcomes included change in PROM scores, change in macular thickness, change in retinopathy and macular morphology, and safety profile.

RESULTS

The mean change in BCVA was +1.48 (SD 14.8) in the fixed arm vs -0.17 (SD 13.1) in the PRN arm, with adjusted effect estimate +0.97, 90% confidence interval (-4.01, +5.95), P=0.02 (per protocol analysis). The conclusions of the ITT analysis were primarily supportive, -0.34 (-5.49, 4.81) P=0.07, but sensitive to an alternative assumption on missing data, +0.28 (-4.72, 5.27) P=0.04.

CONCLUSIONS

The mean change in BCVA with 5-monthly fixed dosing of Ozurdex was non-inferior to OCT-guided PRN Ozurdex therapy for refractory DMO based on a per protocol analysis.

Novel Therapies in Development for Diabetic Macular Edema

Diabetic macular edema (DME) secondary to diabetic retinopathy (DR) is a major cause for functional visual loss in the developed world. Laser photocoagulation has been used for decades in the treatment of DME. However, the advent of anti-vascular endothelial growth factor (anti-VEGF) has revolutionized the treatment of DME. Three important anti-VEGF agents whose efficacy has been well established via phase III clinical trials include ranibizumab, bevacizumab, and aflibercept. However, even in the era of anti-VEGF therapies, there are some challenges that retina specialists have to confront in managing patients with DME. These include the need for frequent treatment and an unpredictable response to therapy. There is evidence to suggest that pathways other than the VEGF pathway may be playing a role in the development of DME. Thus, extensive research is focused on development of novel agents that target these pathways. This review focuses on novel therapeutic agents in development, which may be used as a monotherapy or in combination with anti-VEGF agents, for the management of DME in the future.

Nanoengineering of therapeutics for retinal vascular disease

Retinal vascular diseases, including diabetic retinopathy, neovascular age related macular degeneration, and retinal vein occlusion, are leading causes of blindness in the Western world. These diseases share several common disease mechanisms, including vascular endothelial growth factor (VEGF) signaling, hypoxia, and inflammation, which provide opportunities for common therapeutic strategies. Treatment of these diseases using laser therapy, anti-VEGF injections, and/or steroids has significantly improved clinical outcomes. However, these strategies do not address the underlying root causes of pathology, and may have deleterious side effects. Furthermore, many patients continue to progress toward legal blindness despite receiving regular therapy. Nanomedicine, the engineering of therapeutics at the 1-100 nm scale, is a promising approach for improving clinical management of retinal vascular diseases. Nanomedicine-based technologies have the potential to revolutionize the treatment of ophthalmology, through enabling sustained release of drugs over several months, reducing side effects due to specific targeting of dysfunctional cells, and interfacing with currently "undruggable" targets. We will discuss emerging nanomedicine-based applications for the treatment of complications associated with retinal vascular diseases, including angiogenesis and inflammation.

Pharmacokinetic evaluation of pegaptanib octasodium for the treatment of diabetic edema

INTRODUCTION

Diabetic macular edema (DME) is a leading cause of visual impairment in patients with diabetic retinopathy. Pegaptanib octasodium (Macugen) was the first anti-VEGF agent approved for the treatment of neovascular age-related macular degeneration. It is a selective anti-VEGF agent, which only blocks VEGF. It has been shown to be safe and effective in treatment of DME in randomized controlled trials and it may be a safer first-line treatment in patients with diabetes with a predisposition to cardiovascular risk factors.

AREAS COVERED

This review covers the pharmacokinetics of pegaptanib octasodium. The authors also evaluate pegaptanib octasodium's clinical efficacy, safety and tolerability in DME.

EXPERT OPINION

DME is the most common cause of visual loss in patients with diabetes. Pegaptanib has been found to be more effective than laser therapy alone for center-involving DME, its efficacy might be slightly worse than other pan-VEGF blockers, but the number of patients that have significant improvement of vision after treatment are similar to those treated with pan-VEGF blockers. As a selective VEGF blocker, it may have a better ocular and systemic safety profile than pan-VEGF blocking agents. It is reasonable to consider pegaptanib as the first-line treatment for center-involving DME with pan-VEGF blockers reserved for non-responders.

Molecular basis of the inner blood-retinal barrier and its breakdown in diabetic macular edema and other pathological conditions

Breakdown of the inner endothelial blood-retinal barrier (BRB), as occurs in diabetic retinopathy, age-related macular degeneration, retinal vein occlusions, uveitis and other chronic retinal diseases, results in vasogenic edema and neural tissue damage, causing loss of vision. The central mechanism of altered BRB function is a change in the permeability characteristics of retinal endothelial cells caused by elevated levels of growth factors, cytokines, advanced glycation end products, inflammation, hyperglycemia and loss of pericytes. Subsequently, paracellular but also transcellular transport across the retinal vascular wall increases via opening of endothelial intercellular junctions and qualitative and quantitative changes in endothelial caveolar transcellular transport, respectively. Functional changes in pericytes and astrocytes, as well as structural changes in the composition of the endothelial glycocalyx and the basal lamina around BRB endothelium further facilitate BRB leakage. As Starling's rules apply, active transcellular transport of plasma proteins by the BRB endothelial cells causing increased interstitial osmotic pressure is probably the main factor in the formation of macular edema. The understanding of the complex cellular and molecular processes involved in BRB leakage has grown rapidly in recent years. Although appropriate animal models for human conditions like diabetic macular edema are lacking, these insights have provided tools for rational design of drugs aimed at restoring the BRB as well as for design of effective transport of drugs across the BRB, to treat the chronic retinal diseases such as diabetic macular edema that affect the quality-of-life of millions of patients.