Dexamethasone intravitreal implant in combination with laser photocoagulation for the treatment of diffuse diabetic macular edema

Comparison of ranibizumab, aflibercept, and dexamethasone implant monotherapy in treatment-naive eyes with diabetic macular edema: A 12-month real-life experience

PURPOSE

To compare the functional and anatomical outcomes of ranibizumab, aflibercept, and dexamethasone implant monotherapy in treatment-naive eyes with diabetic macular edema (DME) in real-life conditions.

METHODS

In this retrospective cohort study, data were obtained from the hospital database of treatment-naive patients diagnosed with DME with at least 12 months of follow-up. Best corrected visual acuity (BCVA) and central retinal thickness (CRT) at baseline, third month, sixth month, ninth month, and 12th month were recorded. In addition, a subgroup analysis was performed based on having good (below 0.4 log of minimum angle of resolution [logMAR]) or poor (0.4 logMAR and above) vision.

RESULTS

A total of 219 eyes of 142 patients were included in the study. The change in the mean BCVA from baseline to 12th month was from 0.62 logMAR to 0.42 logMAR (P < 0.001) in the ranibizumab group, from 0.56 logMAR to 0.39 logMAR (P < 0.001) in the aflibercept group, and from 0.46 logMAR to 0.5 logMAR (P = 0.653) in the dexamethasone group. There was no significant difference between the treatment groups at any time point (P > 0.05). The mean amount of CRT change was statistically significant at 12 months in all groups (ranibizumab: -175.4 µm, aflibercept: -153.3 µm, dexamethasone: -71.4 µm) (P < 0.05). In eyes with initially good vision, the final BCVA at 12 months was significantly better in the ranibizumab group compared to the dexamethasone group (P = 0.008). The aflibercept group had better visual acuity than the dexamethasone group, but there was no statistically significant difference (P = 0.059). There was no significant difference in final BCVA in eyes with initially poor vision. No serious ocular/systemic complications were noted.

CONCLUSION

At the 12th month, a significant decrease in CRT was achieved in all treatment groups, whereas only ranibizumab and aflibercept groups had a significant BCVA increase. In eyes with initially good vision, the final BCVA at 12 months was better in the ranibizumab group compared to the dexamethasone group, whereas it was similar in all groups having initially poor vision.

Comparing the efficacy of glucocorticoids and anti-VEGF in treating diabetic macular edema: systematic review and comprehensive analysis

Introduction

The aim of this study was to better understand the efficacy of various drugs, such as glucocorticoids and anti-vascular endothelial growth factors (VEGF), in the treatment of diabetic macular edema (DME), and to evaluate various clinical treatment regimens consisting of different therapeutic measures.

Methods

This study included randomized controlled trials up to February 2023 comparing the efficacy of corticosteroid-related therapy and anti-VEGF therapy. PubMed, the Cochrane Library, and Embase were searched, and the quality of the studies was carefully assessed. Finally, 39 studies were included.

Results

Results at 3-month followup showed that intravitreal injection of bevacizumab (IVB) + triamcinolone acetonide (TA) was the most beneficial in improving best-corrected visual acuity and reducing the thickness of macular edema in the center of the retina in patients with DME. Results at 6-month follow-up showed that intravitreal dexamethasone (DEX) was the most effective in improving patients' bestcorrected visual acuity and reducing the thickness of central macular edema.

Discussion

Overall, IVB+TA was beneficial in improving best-corrected visual acuity and reducing central macular edema thickness over a 3-month follow-up period, while DEX implants had a better therapeutic effect than anti-VEGF agents at 6 months, especially the patients with severe macular edema and visual acuity impaired.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=397100, identifier CRD42023397100.

The Treatment of Diabetic Retinal Edema with Intravitreal Steroids: How and When

Diabetic macular edema (DME) is a common complication of diabetes mellitus and a leading cause of visual impairment worldwide. It is defined as the diabetes-related accumulation of fluid, proteins, and lipids, with retinal thickening, within the macular area. DME affects a significant proportion of individuals with diabetes, with the prevalence increasing with disease duration and severity. It is estimated that approximately 25-30% of diabetic patients will develop DME during their lifetime. Poor glycemic control, hypertension, hyperlipidemia, diabetes duration, and genetic predisposition are recognized as risk factors for the development and progression of DME. Although the exact pathophysiology is still not completely understood, it has been demonstrated that chronic hyperglycemia triggers a cascade of biochemical processes, including increased oxidative stress, inflammation, activation of vascular endothelial growth factor (VEGF), cellular dysfunction, and apoptosis, with breakdown of the blood-retinal barriers and fluid accumulation within the macular area. Early diagnosis and appropriate management of DME are crucial for improving visual outcomes. Although the control of systemic risk factors still remains the most important strategy in DME treatment, intravitreal pharmacotherapy with anti-VEGF molecules or steroids is currently considered the first-line approach in DME patients, whereas macular laser photocoagulation and pars plana vitrectomy may be useful in selected cases. Available intravitreal steroids, including triamcinolone acetonide injections and dexamethasone and fluocinolone acetonide implants, exert their therapeutic effect by reducing inflammation, inhibiting VEGF expression, stabilizing the blood-retinal barrier and thus reducing vascular permeability. They have been demonstrated to be effective in reducing macular edema and improving visual outcomes in DME patients but are associated with a high risk of intraocular pressure elevation and cataract development, so their use requires an accurate patient selection. This manuscript aims to provide a comprehensive overview of the pathology, epidemiology, risk factors, physiopathology, clinical features, treatment mechanisms of actions, treatment options, prognosis, and ongoing clinical studies related to the treatment of DME, with particular consideration of intravitreal steroids therapy.

Does dexamethasone implant combination with aflibercept monotherapy affect one-year outcomes in treatment-naive diabetic macular edema with inflammatory biomarkers?

PURPOSE

To compare the anatomical and functional outcomes of the combination of aflibercept and dexamethasone implant (CT) against aflibercept monotherapy (AM) in treatment-naive diabetic macular edema (DME) patients with serous macular detachment and hyperreflective foci.

METHODS

This study included 82 eyes of 82 patients with treatment-naive DME who completed the follow-up period of 12 months. All patients had optical coherence tomography biomarkers of an inflammatory DME phenotype. Patients were consecutively selected and classified into two groups: The CT group consisted of 39 eyes treated with aflibercept therapy and initially combined with a single-dose dexamethasone implant. The AM group consisted of 43 eyes treated with aflibercept alone. The primary outcome measures of the study were the mean reduction of the central macular thickness (CMT) and total macular volume parameters (TMV) and improvement in best-corrected visual acuity.

RESULTS

In both groups, the patient characteristics, including age, gender, duration of diabetes, HbA1c levels, phakic percentage, and diabetic retinopathy status were similar (P > 0.05). The mean reduction in CMT and TMV was significantly higher in the CT group compared to the AM group (P < 0.001 and P = 0.002, respectively). In contrast, mean letter gains were not significantly higher (P = 0.240) at the end of the study. In the CT group, 20.5% of patients showed a transient IOP increase, and 18% developed cataracts. In subgroup analysis, the mean letter gain in pseudophakic eyes was significantly higher (12.5 in the CT vs. 9.3 in the AM group, P = 0.027).

CONCLUSION

The CT, where inflammation is prominent, can provide faster recovery. The pseudophakic eyes seem to be the ideal patient group for CT.

Current Insights into Targeting Strategies for the Effective Therapy of Diseases of the Posterior Eye Segment

The eye is one a unique sophisticated human sense organ with a complex anatomical structure. It is encased by variety of protective barriers as responsible for vision. There has been a paradigm shift in the prevalence of several major vision threatening ocular conditions with enhanced reliance on computer-based technologies in our workaday life and work-from-home modalities although aging, pollution, injury, harmful chemicals, lifestyle changes will always remain the root cause. Treating posterior eye diseases is a challenge faced by clinicians worldwide. The clinical use of conventional drug delivery systems for posterior eye targeting is restricted by the ocular barriers. Indeed, for overcoming various ocular barriers for efficient delivery of the therapeutic moiety and prolonged therapeutic effect requires prudent and target-specific approaches. Therefore, for efficient drug delivery to the posterior ocular segment, advancements in the development of sustained release and nanotechnology-based ocular drug delivery systems have gained immense importance. Therapeutic efficacy and patient compliance are of paramount importance in clinical translation of these investigative drug delivery systems. This review provides an insight into the various strategies employed for improving the treatment efficacies of the posterior eye diseases. Various drug delivery systems such as systemic and intraocular injections, implants have demonstrated promising outcomes, along with that they have also exhibited side-effects, limitations and strategies employed to overcome them are discussed in this review. The application of artificial intelligence-based technologies along with an appreciation of disease, delivery systems, and patient-specific outcomes will likely enable more effective therapy for targeting the posterior eye segment.

Safety and Efficacy of Dexamethasone Intravitreal Implant Given Either First-Line or Second-Line in Diabetic Macular Edema

Diabetic macular edema (DME) is a common sight-threatening complication of diabetic retinopathy (DR) and the leading cause of severe visual impairment among the working-age population. Several therapeutic options are available for the management of DME, including intravitreal corticosteroids. They have been traditionally used as second-line treatment, due to the risk of intraocular pressure increase and cataract-related adverse events. However, attention has recently been focused on the primary or early use of intravitreal corticosteroids, due to growing evidence of the crucial role of inflammation in the pathogenesis of DME. Furthermore, intravitreal steroid implants offer the additional advantage of a longer duration of action compared to anti-vascular endothelial growth factor agents (anti-VEGF). This review aims to summarize the available evidence on the efficacy and safety profile of dexamethasone (DEX) intravitreal implant, with a specific focus on clinical scenarios in which it might be considered or even preferred as first-line treatment option by adequate selection of patients, considering both advantages and possible adverse events. Patients with contraindications to anti-VEGF, DME with high inflammatory OCT biomarkers, pseudophakic patients and phakic patients' candidates to cataract surgery as well as vitrectomized eyes may all benefit from first-line DEX implant. Additionally, DME not responders to anti-VEGF should be considered for a switch to DEX implant and a combination therapy of DEX implant and anti-VEGF could be a valid option in severe and persistent DME.

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

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

Dexamethasone intravitreal implant in diabetic macular oedema refractory to anti-vascular endothelial growth factors: the AUSSIEDEX study

AIM

To evaluate effectiveness of dexamethasone intravitreal implant 0.7 mg (DEX) monotherapy in the AUSSIEDEX study non-responder subgroup, defined by diabetic macular oedema (DME) refractory to anti-vascular endothelial growth factor (anti-VEGF) agents.

METHODS

This prospective, open-label, observational, real-world study included pseudophakic and phakic (scheduled for cataract surgery) eyes that did not achieve a ≥5-letter best corrected visual acuity (BCVA) gain and/or clinically significant central subfield retinal thickness (CRT) improvement after 3-6 anti-VEGF injections for DME (N=143 eyes), regardless of baseline BCVA and CRT. After an initial DEX injection (baseline visit), reinjection was permitted at ≥16-week intervals.

PRIMARY ENDPOINTS

changes in mean BCVA and CRT from baseline to week 52. Safety assessments included adverse events.

RESULTS

Of 143 eyes, 53 (37.1%) and 89 (62.2%) switched to DEX after 3-6 (early) and >6 (late) anti-VEGF injections, respectively; 1 (0.7%) had missing information. With 2.3 injections (mean) over 52 weeks, the change in mean BCVA from a baseline of 57.8 letters was not significant at week 52. Mean CRT improved significantly from a baseline of 417.8 μm at week 52 (mean change -60.9 μm; p<0.001). Outcomes were similar in eyes switched to DEX early and late. No unexpected adverse events were reported; no filtration surgeries were required.

CONCLUSION

To date, AUSSIEDEX is the largest prospective, real-world study of DEX monotherapy for treatment-naïve or anti-VEGF-refractory DME. Following early or late switch from anti-VEGF agents, DEX significantly improved anatomic outcomes at 52 weeks without new safety concerns, supporting use in anti-VEGF-refractory DME.

TRIAL REGISTRATION NUMBER

NCT02731911.

The Role of Laser Photocoagulation in Treating Diabetic Macular Edema in the Era of Intravitreal Drug Administration: A Descriptive Review

Background and Objectives: This study aimed to elucidate the role of laser photocoagulation therapy in the treatment of diabetic macular edema (DME) as an alternative to, or in conjunction with, the first-line treatment, anti-vascular endothelial growth factor (VEGF). Materials and Methods: A comprehensive literature search to identify studies that evaluated the efficacy of laser photocoagulation therapy in the management of DME was performed. The relevant findings of the efficacy of focal/grid laser therapy from data in randomized, controlled trials were synthesized, and the potential of new laser technologies, such as navigated laser systems, pattern scan lasers, and subthreshold lasers, was explored. The usefulness of multimodal imaging-guided laser therapy was also evaluated, with a focus on the potential contribution to anti-VEGF therapy. Results: Focal laser photocoagulation targeting microaneurysms remains an effective therapeutic approach to chronic refractory edema, despite the widespread use of anti-VEGF therapy. To achieve the best possible treatment outcomes, precise identification of microaneurysms is essential. This requires the use of multimodal imaging-guided, highly accurate, minimally invasive coagulation techniques. Subthreshold laser therapy can also reduce the frequency of anti-VEGF injections and minimize treatment burden. Conclusions: Further studies are needed to determine the optimal timing and settings for laser photocoagulation therapy and the potential of new laser technologies in the management of DME. Nevertheless, laser photocoagulation therapy plays an important role in the management of DME, in conjunction with anti-VEGF therapy.

The evolving therapeutic landscape of diabetic retinopathy

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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

Anti-vascular endothelial growth factor for diabetic macular oedema: a network meta-analysis

Background

Diabetic macular oedema (DMO) is a common complication of diabetic retinopathy. Antiangiogenic therapy with anti-vascular endothelial growth factor (anti-VEGF) can reduce oedema, improve vision, and prevent further visual loss. These drugs have replaced laser photocoagulation as the standard of care for people with DMO. In the previous update of this review, we found moderate-quality evidence that, at 12 months, aflibercept was slightly more effective than ranibizumab and bevacizumab for improving vision in people with DMO, although the difference may have been clinically insignificant (less than 0.1 logarithm of the minimum angle of resolution (logMAR), or five Early Treatment Diabetic Retinopathy Study (ETDRS) letters, or one ETDRS line).

Objectives

The objective of this updated review was to compare the effectiveness and safety of the different anti-VEGF drugs in RCTs at longer followup (24 months).

Search methods

We searched various electronic databases on 8 July 2022.

Selection criteria

We included randomised controlled trials (RCTs) that compared any anti-angiogenic drug with an anti-VEGF mechanism of action versus another anti-VEGF drug, another treatment, sham, or no treatment in people with DMO.

Data collection and analysis

We used standard Cochrane methods for pairwise meta-analysis and we augmented this evidence using network meta-analysis (NMA) methods. We used the Stata 'network' meta-analysis package for all analyses. We used the CINeMA (Confidence in Network Meta-Analysis) web application to grade the certainty of the evidence.

Main results

We included 23 studies (13 with industry funding) that enrolled 3513 people with DMO (median central retinal thickness (CRT) 460 microns, interquartile range (IQR) 424 to 482) and moderate vision loss (median best-corrected visual acuity (BCVA) 0.48 logMAR, IQR 0.42 to 0.55. One study that investigated ranibizumab versus sham and one study that mainly enrolled people with subclinical DMO and normal BCVA were not suitable for inclusion in the efficacy NMA. Consistent with the previous update of this review, we used ranibizumab as the reference drug for efficacy, and control (including laser, observation, and sham) as the reference for systemic safety. Eight trials provided data on the primary outcome (change in BCVA at 24 months, in logMAR: lower is better). We found no evidence of a difference between the following interventions and ranibizumab alone: aflibercept (mean difference (MD) -0.05 logMAR, 95% confidence interval (CI) -0.12 to 0.02; moderate certainty); bevacizumab (MD -0.01 logMAR, 95% CI -0.13 to 0.10; low certainty), brolucizumab (MD 0.00 logMAR, 95% CI -0.08 to 0.07; low certainty), ranibizumab plus deferred laser (MD 0.00 logMAR, 95% CI -0.11 to 0.10; low certainty), and ranibizumab plus prompt laser (MD 0.03 logMAR, 95% CI -0.04 to 0.09; very low certainty). We also analysed BCVA change at 12 months, finding moderate-certainty evidence of increased efficacy with brolucizumab (MD -0.07 logMAR, 95%CI -0.10 to -0.03 logMAR), faricimab (MD -0.08 logMAR, 95% CI -0.12 to -0.05), and aflibercept (MD -0.07 logMAR, 95 % CI -0.10 to -0.04) compared to ranibizumab alone, but the difference could be clinically insignificant. Compared to ranibizumab alone, NMA of six trials showed no evidence of a difference with aflibercept (moderate certainty), bevacizumab (low certainty), or ranibizumab with prompt (very low certainty) or deferred laser (low certainty) regarding improvement by three or more ETDRS lines at 24 months. There was moderate-certainty evidence of greater CRT reduction at 24 months with brolucizumab (MD -23 microns, 95% CI -65 to -1 9) and aflibercept (MD -26 microns, 95% CI -53 to 0.9) compared to ranibizumab. There was moderate-certainty evidence of lesser CRT reduction with bevacizumab (MD 28 microns, 95% CI 0 to 56), ranibizumab plus deferred laser (MD 63 microns, 95% CI 18 to 109), and ranibizumab plus prompt laser (MD 72 microns, 95% CI 25 to 119) compared with ranibizumab alone. Regarding all-cause mortality at the longest available follow-up (20 trials), we found no evidence of increased risk of death for any drug compared to control, although effects were in the direction of an increase, and clinically relevant increases could not be ruled out. The certainty of this evidence was low for bevacizumab (risk ratio (RR) 2.10, 95% CI 0.75 to 5.88), brolucizumab (RR 2.92, 95% CI 0.68 to 12.58), faricimab (RR 1.91, 95% CI 0.45 to 8.00), ranibizumab (RR 1.26, 95% CI 0.68 to 2.34), and very low for conbercept (RR 0.33, 95% CI 0.01 to 8.81) and aflibercept (RR 1.48, 95% CI 0.79 to 2.77). Estimates for Antiplatelet Trialists Collaboration arterial thromboembolic events at 24 months did not suggest an increase with any drug compared to control, but the NMA was overall incoherent and the evidence was of low or very low certainty. Ocular adverse events were rare and poorly reported and could not be assessed in NMAs.

Authors' conclusions

There is limited evidence of the comparative efficacy and safety of anti-VEGF drugs beyond one year of follow-up. We found no clinically important differences in visual outcomes at 24 months in people with DMO, although there were differences in CRT change. We found no evidence that any drug increases all-cause mortality compared to control, but estimates were very imprecise. Evidence from RCTs may not apply to real-world practice, where people in need of antiangiogenic treatment are often under-treated, and the individuals exposed to these drugs may be less healthy than trial participants.

Visual function and retinal morphological changes after single suprachoroidal delivery of fluocinolone acetonide (Iluvien®) implant in eyes with chronic diabetic macular edema

BACKGROUND

To assess the efficacy and safety of supra-choroidal (SC) Iluvien in the management of chronic diabetic macular edema (DME).

METHODS

A retrospective interventional non-comparative consecutive case series including patients with chronic DME who received an SC Iluvien implant. All patients had persistent central macular thickness (CMT) ≥ 300µ after previous treatment with anti-vascular endothelial growth factor (VEGF) agents or laser photocoagulation. The main outcome measures were improvement of best-corrected visual acuity (BCVA), reduction of CMT, and detection of ocular hypertension/glaucoma or cataract formation. Friedman's two-way ANOVA was used to analyze BCVA, intraocular pressure (IOP), and DME across different time points. P-value = 0.05.

RESULTS

The study included 12 eyes of 12 patients. Six patients (50%) were males. The median age was 58 years (range 52-76 years). The median duration of DM was 13 years (range 8-20 years). Ten patients (83.3%) were phakic and 2 patients (17%) were pseudophakic. The median pre-operative BCVA was 0.07 (range 0.05-0.8). The median pre-operative CMT was 544µ (range 354-745µ). The median pre-operative IOP was 17 mmHg (range 14-21mmHg). The median follow-up period was 12 months, range (12-42). Post-operatively, the median final BCVA was 0.15 (range 0.03-1), p 0.02, the median CMT was 404µ (range 213-747), p 0.4 and the median IOP was 19.5 mmHg (range 15-22), p 1. Two out of 10 phakic patients (20%) developed nuclear sclerosis grade I by 12 months. Six patients (50%) developed a transient rise in IOP < 10 mmHg from the baseline that resolved within 3 weeks with antiglaucoma drops.

CONCLUSION

SC Iluvien is potentially effective in improving visual function, reducing macular edema, and reducing the incidence of steroid-induced cataracts and glaucoma.

Management of Patients with Diabetic Macular Edema Switched from Dexamethasone Intravitreal Implant to Fluocinolone Acetonide Intravitreal Implant

To assess anatomical and functional outcomes after switching from dexamethasone implant (DEXi) to fluocinolone acetonide implant (FAci) in 113 diabetic macular edema eyes, a multicentric retrospective observational study was conducted. Seventy-five eyes (73.5%) were switched 1−8 weeks after their last DEXi. The mean best-corrected visual acuity improved to 59.8 letters at month 4 and remained stable during the follow-up. The mean central macular thickness (CMT) significantly decreased during the follow-up, with a minimum of 320.9 μm at month 3. The baseline CMT was higher in eyes that received the last DEXi >8 weeks versus <8 weeks before the first FAci (p < 0.021). After FAci injection, additional treatments were needed in 37 (32.7%) eyes. A longer diabetes duration (p = 0.009), a longer time between the last DEXi and the first FAci (p = 0.035), and a high baseline CMT (p = 0.003) were risk factors for additional treatments. The mean intraocular pressure was <19 mmHg at all timepoints, with no difference between eyes receiving the last DEXi ≤8 weeks or >8 weeks before the switch. Switching from DEXi to FAci in DME is effective and safe. A short time between the last DEXi and the first FAci reduced CMT fluctuations and the need for early additional treatments.

Describing Adverse Events Associated with Bilateral Same-Day Intravitreal Dexamethasone Implants

BACKGROUND AND OBJECTIVES

To explore the incidence of adverse events after bilateral same-day intravitreal 0.7-mg dexamethasone implant (SDIDI) injections.

MATERIALS AND METHODS

We performed an IRB approved, single-center, retrospective review of patients receiving bilateral SDIDI injections from January 1, 2016 to October 31, 2021 and reviewed adverse events that occurred within 3 months of injection.

RESULTS

A total of 206 bilateral (412 eyes) SDIDI injections were performed in 59 patients. Ocular hypertension or the addition of intraocular pressure (IOP) lowering drops occurred in 121 (29.4%) eyes after IDI. Two (0.5%) eyes required glaucoma drainage surgeries. Of the 117 phakic eyes, 32 (27.4%) had progression of cataract or cataract extraction. There were two (0.5%) episodes of vitreous hemorrhage and one (0.2%) retinal tear with retinal detachment. There were no cases of endophthalmitis.

CONCLUSION

Serious complication rates after bilateral same-day IDI injections appears low. Increased IOP that requires intervention can occur. [Ophthalmic Surg Lasers Imaging Retina 2022;53:612-618.].

Does dexamethasone inhibit glucose oxidase: an analysis in kinetics and molecular study

OBJECTIVE

Glucose oxidase is an enzyme that is widely used in biosensors, especially kits for measuring blood sugar. Many diabetics use this type of kit to determine their blood sugar level. Aspergillus niger is the most important source of glucose oxidase for use in biosensors. Diabetes causes secondary diseases in patients for which medications are prescribed to improve them. Dexamethasone, a corticosteroid, is one of the drugs prescribed to diabetics to cure some secondary diseases. In this study, the effect of this drug on glucose oxidase was investigated from a kinetic and molecular point of view.

METHODS

In this study, the kinetics of drug binding to the enzyme was measured and the type of inhibition was determined by Lineweaver-Burk plot. The Ki value of the drug was determined by drawing the secondary curve. Using fluorescence spectrophotometry and molecular docking, the binding of the drug to the enzyme was confirmed.

RESULTS

The results showed that the drug inhibits the enzyme non-competitively. Determining the kinetics parameters of the drug-enzyme interaction showed that the drug acts as a potent inhibitor. Study at the molecular level by fluorescence spectrophotometer showed that the drug attachment alters the enzyme conformation to more compaction. In silico results showed that the drug is placed between two helices that are outside the active site and binds to the enzyme by three hydrogen bonds.

CONCLUSIONS

The result of this study is useful because it suggests that in diabetic patients taking dexamethasone, the amount of glucose declared by the kit may not be real due to the inhibition of glucose oxidase.

Current and Novel Therapeutic Approaches for Treatment of Diabetic Macular Edema

Diabetic macular edema (DME) is a major ocular complication of diabetes mellitus (DM), leading to significant visual impairment. DME’s pathogenesis is multifactorial. Focal edema tends to occur when primary metabolic abnormalities lead to a persistent hyperglycemic state, causing the development of microaneurysms, often with extravascular lipoprotein in a circinate pattern around the focal leakage. On the other hand, diffusion edema is due to a generalized breakdown of the inner blood–retinal barrier, leading to profuse early leakage from the entire capillary bed of the posterior pole with the subsequent extravasation of fluid into the extracellular space. The pathogenesis of DME occurs through the interaction of multiple molecular mediators, including the overexpression of several growth factors, including vascular endothelial growth factor (VEGF), insulin-like growth factor-1, angiopoietin-1, and -2, stromal-derived factor-1, fibroblast growth factor-2, and tumor necrosis factor. Synergistically, these growth factors mediate angiogenesis, protease production, endothelial cell proliferation, and migration. Treatment for DME generally involves primary management of DM, laser photocoagulation, and pharmacotherapeutics targeting mediators, namely, the anti-VEGF pathway. The emergence of anti-VEGF therapies has resulted in significant clinical improvements compared to laser therapy alone. However, multiple factors influencing the visual outcome after anti-VEGF treatment and the presence of anti-VEGF non-responders have necessitated the development of new pharmacotherapies. In this review, we explore the pathophysiology of DME and current management strategies. In addition, we provide a comprehensive analysis of emerging therapeutic approaches to the treatment of DME.

Dexamethasone Intravitreal Implant for the Treatment of Macular Edema and Uveitis: A Comprehensive Narrative Review

Purpose

The purpose of this review article is to provide a comprehensive review of the current applications of intravitreal DEX implant (Ozurdex^®, Allergan Inc, Irvine, CA) for a variety of ophthalmic conditions – ranging from FDA approved indications to off-label uses. We have attempted to provide relevant evidence from the literature to help a reader develop an understanding of the biological and pharmacokinetic properties of DEX implant, its uses, and potential side effects.

Methods

PubMed searches were performed using the terms “Ozurdex”, or “intravitreal DEX implant”, AND “retinal vein occlusion”, or “diabetic macular edema”, or “uveitis”. The search was performed in July of 2021, with an additional search in October 2021. All original English language articles were considered for this review.

Results

DEX implant has evidence of efficacy in a variety of clinical situations including macular edema associated with retinal vein occlusion, diabetes, uveitis, and others. Safety concerns include cataract formation and progression, intraocular pressure elevation, complications related to intravitreal injection, and opportunistic infections secondary to steroid-induced immune suppression.

Conclusion

DEX implant is a useful tool in the management of several retinal disorders. Further studies are needed for head-to-head comparison with other treatment modalities and to determine its precise place in clinical practice.

Cost-effectiveness of dexamethasone and triamcinolone for the treatment of diabetic macular oedema in Finland: A Markov-model

PURPOSE

Diabetic macular oedema (DMO), a complication of diabetes, causes vision loss and blindness. Corticosteroids are usually used as a second-line treatment. The aim of this study was to analyse the cost-effectiveness of dexamethasone implants compared to cheaper and more frequently applied triamcinolone injections.

METHODS

Markov-modelling, which incorporated both eyes, was used for economic evaluation. The model consisted of five health states based on visual acuity, illustrating the progression of DMO. A cycle length of five months was chosen for dexamethasone and four months for triamcinolone. Time horizons of two and five years were applied. Transition probabilities and health state utilities were sourced from previous studies. The perspective used in this analysis was the hospital perspective. The health care costs were acquired from Kuopio University Hospital in Finland.

RESULTS

In this cost-effectiveness analysis, the incremental cost-effectiveness ratio ICER with 3% discount rate was €56 591/QALY for a two-year follow-up and -€1 110 942/QALY for a five-year follow-up. In order to consider dexamethasone as cost-effective over a 2-year time horizon, the WTP needs to be around €55 000/QALY. Over the five-year follow-up, triamcinolone is clearly a dominant treatment. Sensitivity analyses support the cost-effectiveness of dexamethasone over a 2-year time horizon.

CONCLUSIONS

Since the sensitivity analyses support the results, dexamethasone would be a cost-effective treatment during the first two years with WTP threshold around €55 000/QALY, and triamcinolone would be a convenient treatment after that. This recommendation is in line with the guidelines of EURETINA.

Multicenter, Prospective, Randomized Study of Dexamethasone Intravitreal Implant in Patients with Center-Involved Diabetic Macular Edema in the Asia-Pacific Region

Purpose

To evaluate the safety and efficacy of dexamethasone intravitreal implant 0.7 mg (DEX) compared with laser photocoagulation in patients with diabetic macular edema (DME).

Patients and Methods

This Phase 3, multicenter, randomized, efficacy evaluator–masked, parallel-group, 12-month clinical study enrolled adults in China and the Philippines with reduced visual acuity secondary to fovea-involved DME in the study eye. Participants were randomized 1:1 to study eye treatment with laser photocoagulation every 3 months as needed (n = 139) or DEX every 5 months (n = 145). The main efficacy measures were best-corrected visual acuity (BCVA), central retinal thickness (CRT), and leakage area. The primary endpoint was the average change in BCVA from baseline over 12 months (area-under-the-curve method). Preplanned subgroup analyses evaluated outcomes in Chinese patients.

Results

Mean average change in BCVA from baseline during the study (letters) was 4.3 with DEX (n = 145) versus 1.4 with laser (n = 127) overall (P = 0.001) and 4.6 with DEX (n = 129) versus 0.6 with laser (n = 113) in Chinese patients (P < 0.001). At Month 12, mean change in CRT from baseline was −209.5 μm with DEX versus −120.3 μm with laser (P < 0.001) and mean change in total leakage area from baseline was −8.367 mm² with DEX versus −0.637 mm² with laser (P < 0.001). The most common treatment-emergent adverse events in the DEX group were increased intraocular pressure and cataract.

Conclusion

DEX administered every 5 months provided significantly greater improvement in BCVA, CRT, and total leakage area compared with laser treatment. DEX demonstrated an acceptable safety profile, consistent with an intraocular corticosteroid, and similar to that reported in completed global registration studies.

Intravitreal corticosteroids for diabetic macular edema: a network meta-analysis of randomized controlled trials

BACKGROUND

To evaluate the efficacy and safety of different intravitreal corticosteroids for treating diabetic macular edema (DME).

METHODS

Four databases were systematically searched for randomized controlled trials comparing different intravitreal corticosteroids for treating DME. The primary outcome was the change in best-corrected visual acuity (BCVA) within 6 months after the first injection (short-term BCVA). Secondary outcomes were the change in BCVA over 1 year (long-term BCVA) and changes in central macular thickness (CMT) and intraocular pressure (IOP) within 6 months after the first injection. Network meta-analysis was performed to aggregate the results from the individual studies.

RESULTS

Nineteen trials involving 2839 eyes were included. Intravitreal triamcinolone acetonide (TA) injections (≥ 8 mg and 4-8 mg), fluocinolone acetonide (FA) implants (0.5 µg/day) and dexamethasone (DEX) implants (700 µg) improved short-term BCVA (mean changes in logMAR [95% confidence interval] - 0.27 [- 0.40, - 0.15]; - 0.12 [- 0.18, - 0.06]; - 0.10 [- 0.21, - 0.01]; and - 0.06 [- 0.11, - 0.01]). Intravitreal TA injections (4 mg, multiple times), FA implants (0.5 µg/day and 0.2 µg/day), and DEX implants (350 µg) improved long-term BCVA (mean changes in logMAR [95% confidence interval] - 0.11 [- 0.21, - 0.02]; - 0.09 [- 0.15, - 0.03]; - 0.09 [- 0.14, - 0.02]; and - 0.04 [- 0.07, - 0.01]). All intravitreal corticosteroids reduced CMT, and different dosages of TA did not show significant differences in increasing IOP.

CONCLUSIONS

Intravitreal corticosteroids effectively improved BCVA in DME patients, with higher dosages showing greater efficacies. TA was not inferior to FA or DEX and may be considered a low-cost alternative choice for DME patients. The long-term efficacy and safety of different corticosteroids deserve further investigation. Trial registration Prospectively registered: PROSPERO, CRD42020219870.

Assessment of Reinjection Numbers and Intervals for Diabetic Macular Edema Patients Who Received Dexamethasone Intravitreal Implants in Germany and Switzerland

PURPOSE

The purpose was to assess the number and intervals of dexamethasone intravitreal implant (DEX) reinjections in a real-world setting for the treatment of diabetic macular edema (DME) and to determine the relationship with effectiveness and safety.

PATIENTS AND METHODS

Data were abstracted from medical records of DME patients in Germany and Switzerland for this retrospective, multicenter, drug utilization study. Best-corrected visual acuity (BCVA) and central retinal thickness (CRT) changes 7-12 weeks post-injection(s) measured effectiveness. Adverse events (AEs) of special interest were reported.

RESULTS

A total of 141 patients, 108 from Germany and 33 from Switzerland, were assessed. Mean (SD) reinjection interval was 5.7 (4.2) months. Mean baseline BCVA was 61.6 letters, and mean baseline CRT was 413.3 µm. The mean BCVA and CRT changes at 7-12 weeks after baseline, reinjection 1, 2, and 3 were +3.4, +3.7, +3.2, and -1.4 letters and -88.3, -81.6, -102.4, and -124.1 μm, respectively. The Spearman correlation between change in BCVA and CRT and DEX reinjection interval was r=0.03 (P=0.66) and r=0.07 (P=0.38), respectively. Only 18% of patients experienced at least 1 AE.

CONCLUSION

There was no statistically significant correlation between drug effectiveness and reinjection intervals in either country. Although these results are preliminary, they indicate that DEX improves BCVA and CRT in real-world clinical practice.

Comparison of Intravitreal Dexamethasone Implant and Ranibizumab in Vitrectomized Eyes with Diabetic Macular Edema

Purpose

This retrospective study aimed to compare the efficacy of intravitreal ranibizumab (IVR) and intravitreal dexamethasone implant (IDI) for pseudophakic vitrectomized eyes with diabetic macular edema (DME) in a single institution.

Methods

Pseudophakic vitrectomized eyes with treatment-naïve center-involved DME were enrolled, with one eye in each patient. They were divided into two groups: one group receiving IDI every 3 to 4 months and another group receiving IVR using 3 monthly plus treat-and-extend injections, all with monthly follow-up for 6 months. Switch of intravitreal drugs or deferred macular laser was not allowed. Primary outcome measures included change in central foveal thickness (CFT) in 1 mm by spectral-domain optical coherence tomography and best-corrected visual acuity (BCVA) at Month 6.

Results

Twenty-two eyes were included in the IDI group and 26 eyes in the IVR group. The baseline demographics, glycosylated hemoglobin level, intraocular pressure (IOP), BCVA, and CFT did not significantly differ (p > 0.05). Compared to baseline data, CFT decreased and BCVA improved significantly after either IDI or IVR at Month 6 (p < 0.05). Significantly better mean final BCVA (0.38 logMAR vs. 0.62 logMAR, p=0.04), more mean visual gain (−0.30 logMAR vs. −0.15 logMAR, p=0.02), lower mean final CFT (310.9 μm vs. 384.2 μm, p=0.04), and larger mean CFT decrease (−150.0 μm vs. −60.1 μm, p=0.03) were found in the IDI group compared to those in the IVR group. A smaller mean treatment number (2.6 vs. 5.6, p < 0.001) and higher rate of postinjection ocular hypertension requiring topical hypotensive agent therapy (27.3% vs. 0%, p=0.0002) were demonstrated in the IDI group than those in the IVR group.

Conclusion

We concluded that IDI and IVR can both effectively treat vitrectomized eyes with DME. Dexamethasone implants had significantly better visual/anatomical improvement, smaller treatment number, and higher rate of elevated IOP after injection than IVR in pseudophakic vitrectomized eyes with DME in a 6-month period.

Targeting vascular endothelial growth factor using retinal gene therapy

Pharmacotherapies targeting vascular endothelial growth factor (VEGF) have revolutionized the management for neovascular retinal disorders including diabetic retinopathy and neovascular age-related macular degeneration. However, the burden of frequent injections, high cost, and treatment resistance in some patients remain unresolved. To overcome these challenges, newer generations of anti-angiogenic biological therapies, engineered proteins, implantable delivery systems, and biopolymers are currently being developed to enable more sustained, longer-lasting treatments. The use of gene therapies for pathologic angiogenesis has garnered renewed interests since the first FDA-approval of a gene therapy to treat inherited retinal diseases associated with biallelic RPE65 mutations. Newer generations of viral vectors and novel methods of intraocular injections helped overcome ocular barriers, improving the efficiency of transduction as well as safety profile. In addition, unlike current anti-VEGF gene therapy strategies which employ a biofactory approach to mimic existing pharmacotherapies, novel genome editing strategies that target pro-angiogenic factors at the DNA level offer a unique and distinct mechanistic approach that can potentially be more precise and lead to a permanent cure. Here, we review current anti-VEGF therapies and newer pharmacologic agents under development, examine technologies and progress in adapting anti-VEGF gene therapies, and explore the future application of CRISPR-Cas9 technology to suppress ocular angiogenesis.

Visual/anatomical outcome of diabetic macular edema patients lost to follow-up for more than 1 year

To investigate the visual/anatomical outcome of diabetic macular edema (DME) patients lost to follow-up (LTFU) for more than 1 year during intravitreal anti-VEGF treatment. A retrospective review of 182 treatment-naïve DME patients was performed. Among them, we identified patients LTFU for more than 1 year during anti-VEGF treatment. Visual acuity and anatomic outcomes at the first visit, last visit before being LTFU, return visit, and after re-treatment were analyzed and compared with those of DME patients with regular follow-up. Patients who had continuous follow-up visits were assigned to the control group. Sixty patients (33%) with DME were LTFU for more than 1 year during anti-VEGF treatment. Multivariate analysis revealed that the ratio of male (p = 0.004), diabetes mellitus (DM) duration less than 5 years (p = 0.015), and poor early anatomic response (p = 0.012) were higher compared to the control group. Eighteen patients returned to the clinic and received re-treatment. After re-treatment with anti-VEGF, central subfield thickness (CST) was significantly improved to the CST of before LTFU. However, visual acuity did not recover to the level before LTFU (0.63 ± 0.26 vs. 0.45 ± 0.28, p = 0.003). About thirty percent of DME patients were LTFU for more than 1 year. Permanent visual loss was observed in these LTFU patients. Patients with a high risk of LTFU such as male, early DM, and poor response after initial injections should be treated more aggressively to improve the visual outcomes.

Place of intravitreal dexamethasone implant in the treatment armamentarium of diabetic macular edema

Diabetic macular edema (DME) is a very important and well-known cause of visual loss in diabetics. Blood–retina barrier disruption and consequent intraretinal fluid accumulation may lead to retinal thickening at the posterior pole namely DME. Even though it is not clearly understood, current evidence suggests that chronic low-grade inflammation characterized with various cytokines has a major role in the occurrence of DME. Clinical trials are continuously shaping our treatment approaches for the eyes with DME. Today, vascular endothelial growth factor (VEGF) inhibitor and steroid administrations are the main alternatives in DME treatment. Dexamethasone (DEX) implant (Ozurdex^®; Allergan, Inc., Irvine, CA, United States) was approved by the United States Food & Drug Administration in 2014 for DME treatment. The implant is made up of a biodegradable solid copolymer that is broken down by releasing its active ingredient into the vitreous cavity over time. Biphasic release feature of this sustained-release drug delivery system ensures its efficacy for up to 6 mo with an acceptable and manageable safety profile. DEX implant provides a favorable anatomical and functional outcome in DME as shown in several randomized-controlled studies but has a relatively higher ocular side-effect profile such as increased risk of cataract formation and raised intraocular pressure when compared to the gold standard anti-VEGF agents. Thus, DEX implant becomes the second-line treatment option demonstrating inadequate clinical response to anti-VEGF therapy. However, it can be preferred as the first-line treatment in vitrectomized and pseudophakic eyes. Even in some selected conditions DEX implant is favored over anti-VEGF agents where the use of VEGF-inhibitors is either inappropriate or contraindicated such as the patients with a recent history of a major cardiovascular or cerebrovascular event, pregnancy and noncompliant to frequent visits. This mini-review briefly overviews the efficacy, safety profile and complications of DEX implant and summarizes the outcome of DEX implant administration in major clinical studies on DME treatment.

Challenges in Diabetic Macular Edema Management: An Expert Consensus Report

Purpose

This paper aimed to present daily-practice recommendations for the management of diabetic macular edema (DME) patients based on available scientific evidence and the clinical experience of the consensus panel.

Methods

A group of Spanish retina experts agreed to discuss different aspects related with the clinical management of DME patients.

Results

Panel was mainly focused on therapeutic objectives in DME management; definition terms; and role of biomarkers as prognostic and predictive factors to intravitreal treatment response. The panel recommends to start DME treatment as soon as possible in those eyes with a visual acuity less than 20/25 (always according to the retina unit capacity). Naïve patient was defined, in a strict manner, as a patient who, up to that moment, had never received any treatment. A refractory DME patient may be defined as the one who did not achieve a complete resolution of the disease, regardless of the treatment administered. Different optical coherence tomography biomarkers, such as disorganization of the retinal inner layers, hyperreflective dots, and cysts, have been identified as prognostic factors.

Conclusion

This document has sought to lay down a set of recommendations and to identify key issues that may be useful for the daily management of DME patients.

Diabetic retinopathy and diabetic macular oedema pathways and management: UK Consensus Working Group

The management of diabetic retinopathy (DR) has evolved considerably over the past decade, with the availability of new technologies (diagnostic and therapeutic). As such, the existing Royal College of Ophthalmologists DR Guidelines (2013) are outdated, and to the best of our knowledge are not under revision at present. Furthermore, there are no other UK guidelines covering all available treatments, and there seems to be significant variation around the UK in the management of diabetic macular oedema (DMO). This manuscript provides a summary of reviews the pathogenesis of DR and DMO, including role of vascular endothelial growth factor (VEGF) and non-VEGF cytokines, clinical grading/classification of DMO vis a vis current terminology (of centre-involving [CI-DMO], or non-centre involving [nCI-DMO], systemic risks and their management). The excellent UK DR Screening (DRS) service has continued to evolve and remains world-leading. However, challenges remain, as there are significant variations in equipment used, and reproducible standards of DMO screening nationally. The interphase between DRS and the hospital eye service can only be strengthened with further improvements. The role of modern technology including optical coherence tomography (OCT) and wide-field imaging, and working practices including virtual clinics and their potential in increasing clinic capacity and improving patient experiences and outcomes are discussed. Similarly, potential roles of home monitoring in diabetic eyes in the future are explored. The role of pharmacological (intravitreal injections [IVT] of anti-VEGFs and steroids) and laser therapies are summarised. Generally, IVT anti-VEGF are offered as first line pharmacologic therapy. As requirements of diabetic patients in particular patient groups may vary, including pregnant women, children, and persons with learning difficulties, it is important that DR management is personalised in such particular patient groups. First choice therapy needs to be individualised in these cases and may be intravitreal steroids rather than the standard choice of anti-VEGF agents. Some of these, but not all, are discussed in this document.

SYSTEMIC FACTORS AND EARLY TREATMENT RESPONSE TO INTRAVITREAL INJECTION FOR DIABETIC MACULAR EDEMA: The Role of Renal Function

PURPOSE

To investigate the effect of systemic factors on early treatment response to intravitreal bevacizumab injection (IVBI) and intravitreal dexamethasone implant (IVDI) in patients with diabetic macular edema (DME).

METHODS

We reviewed the medical records of 117 treatment naïve DME patients who underwent IVBI. We divided the patients according to their IVBI response. An IVDI was performed in patients with poor response to IVBIs. We investigated the various systemic factors of diabetic patients and examined the relationship between systemic factors and the treatment response to IVBI and IVDI.

RESULTS

In a total of 117 treatment naïve DME eyes, 61 eyes (52.14%) were classified as IVBI responders. An IVDI was performed in 23 of 56 eyes with poor response to IVBI, and 17 eyes (73.91%) had a good response. Among various systemic factors of patients with diabetes, renal function (blood urea nitrogen, creatinine, and estimated glomerular filtration rate) showed a significant negative correlation with central subfield retinal thickness improvement after treatment (P < 0.05). However, there was no difference in HbA1C levels regarding the treatment response to IVBI and IVDI.

CONCLUSION

Renal function was significantly worse in patients with a poor response to IVBI and IVDI. Renal function could be used as a possible predictor for treatment response in certain patients with DME. Furthermore, for patients with DME with poor responses to anti-vascular endothelial growth factor or steroid treatments, assessment of renal function could help explain the poor treatment response.

Polymeric Implants for the Treatment of Intraocular Eye Diseases: Trends in Biodegradable and Non-Biodegradable Materials

Intraocular/Intravitreal implants constitute a relatively new method to treat eye diseases successfully due to the possibility of releasing drugs in a controlled and prolonged way. This particularity has made this kind of method preferred over other methods such as intravitreal injections or eye drops. However, there are some risks and complications associated with the use of eye implants, the body response being the most important. Therefore, material selection is a crucial factor to be considered for patient care since implant acceptance is closely related to the physical and chemical properties of the material from which the device is made. In this regard, there are two major categories of materials used in the development of eye implants: non-biodegradables and biodegradables. Although non-biodegradable implants are able to work as drug reservoirs, their surgical requirements make them uncomfortable and invasive for the patient and may put the eyeball at risk. Therefore, it would be expected that the human body responds better when treated with biodegradable implants due to their inherent nature and fewer surgical concerns. Thus, this review provides a summary and discussion of the most common non-biodegradable and biodegradable materials employed for the development of experimental and commercially available ocular delivery implants.

COMPARISON OF INTRAVITREAL DEXAMETHASONE IMPLANT AND AFLIBERCEPT IN PATIENTS WITH TREATMENT-NAIVE DIABETIC MACULAR EDEMA WITH SEROUS RETINAL DETACHMENT

PURPOSE

To compare the efficacy and safety of intravitreal dexamethasone (DEX) implant versus aflibercept in patients with treatment-naive diabetic macular edema with inflammatory biomarkers.

METHODS

Ninety-eight eyes of 62 treatment-naive patients with diabetic macular edema with serous retinal detachment and hyperreflective foci were enrolled. Each patient was randomized to receive either aflibercept or DEX implant treatment. The treatment protocol included 3 monthly injections of 2 mg of aflibercept as a loading phase in the anti-vascular endothelial growth factor group and 0.7 mg of DEX implant in the DEX group and then pro re nata treatment. Primary outcome measures were mean changes in visual acuity and central retinal thickness at the end of the 12-month follow-up.

RESULTS

Forty-eight eyes of 29 patients were received DEX implant, and 50 eyes of 33 patients received the aflibercept injection. Mean central retinal thickness decreased from 615.2 µm at baseline to 297.7 µm at 12 months in the DEX group (P < 0.001) and from 576.5 µm to 367.4 µm in the aflibercept group (P < 0.001). Except for the first month, mean central retinal thickness reduction was significantly higher in the DEX group (P < 0.05, Mann-Whitney U Test). Visual acuity improved significantly at the end of the follow-ups (46.3-52.7 Early Treatment Diabetic Retinopathy Study letters in the DEX group and 47.5-56.8 Early Treatment Diabetic Retinopathy Study letters in the aflibercept group at 12 months, P < 0.001, paired-sample t-test). Adjusting by baseline values, the increase in mean visual acuity during the 12-month follow-ups favored the aflibercept group (P < 0.01), 25% of the DEX-treated eyes and 42% of the aflibercept treated eyes experienced 10 or more Early Treatment Diabetic Retinopathy Study letters visual gain (P: 0.058). The DEX group received significantly fewer (2.6 vs. 7.2) injections (P: 0.001).

CONCLUSION

It was observed that the both of DEX implant and aflibercept were effective and safe in treatment-naive diabetic macular edema patients with inflammatory phenotype. Anatomical results were found to be better in the DEX group, and functional results were found to be better in the aflibercept group. In pseudophakic eyes, the functional superiority of aflibercept ceased to exist, and the low number of injections in the DEX implant group was seen as an advantage.

DIABETIC MACULAR EDEMA AND CATARACT SURGERY: Phacoemulsification Combined With Dexamethasone Intravitreal Implant Compared With Standard Phacoemulsification

PURPOSE

To compare functional and anatomical results of combined phacoemulsification and dexamethasone intravitreal implant (Ozurdex; DEX-I) with standard phacoemulsification in diabetic patients with cataract.

METHODS

Retrospective, comparative, cohort study. Patients with nonproliferative diabetic retinopathy, macular edema, and cataract, treated routinely at the Eye Clinic, Azienda Ospedaliero Universitaria Policlinico, Bari, Italy with phacoemulsification associated with DEX-I (n = 23; Phaco-Dex) or standard phacoemulsification (n = 23; Phaco-alone). Best-correct visual acuity, central subfield thickness, and intraocular pressure were assessed at baseline and monthly for 3 months after surgery, and t-test was used to assess change from baseline. A multilevel regression model with an unstructured correlation-type matrix to account for repeated data measures was used for statistical analysis in and between groups.

RESULTS

With Phaco-Dex, best-correct visual acuity increased significantly from the first month (P = 0.0005 vs. baseline) and remained stable at the following visits; central subfield thickness decreased significantly from Month 2 (P = 0.049 and P = 0.04 vs. baseline, respectively); at each timepoint, central subfield thickness was significantly lower in the Phaco-Dex group versus Phaco-alone. Intraocular pressure increased significantly during follow-up (P = 0.001 at Month 3 vs. baseline) but remained within the normal range. In the Phaco-alone group, best-correct visual acuity, and intraocular pressure did not show any significant changes after surgery, whereas central subfield thickness increased from Month 2 (P = 0.05 vs. baseline).

CONCLUSION

In diabetic patients with macular edema and visually significant cataract, combined treatment with phacoemulsification and DEX-I seemed to be effective, safe, and superior to standard phacoemulsification considering both functional and tomographic parameters.

Bone Morphogenetic Proteins and Diabetic Retinopathy

Bone morphogenetic proteins (BMPs) play an important role in bone formation and repair. Recent studies underscored their essential role in the normal development of several organs and vascular homeostasis in health and diseases. Elevated levels of BMPs have been linked to the development of cardiovascular complications of diabetes mellitus. However, their particular role in the pathogenesis of microvascular dysfunction associated with diabetic retinopathy (DR) is still under-investigated. Accumulated evidence from our and others’ studies suggests the involvement of BMP signaling in retinal inflammation, hyperpermeability and pathological neovascularization in DR and age-related macular degeneration (AMD). Therefore, targeting BMP signaling in diabetes is proposed as a potential therapeutic strategy to halt the development of microvascular dysfunction in retinal diseases, particularly in DR. The goal of this review article is to discuss the biological functions of BMPs, their underlying mechanisms and their potential role in the pathogenesis of DR in particular.

Intravitreal Therapy for Diabetic Macular Edema: An Update

Diabetic macular edema (DME) represents a prevalent and disabling eye condition. Despite that DME represents a sight-threatening condition, it is also among the most accessible to treatment. Many different treatment options including photocoagulation, intravitreal medical treatment (either vascular endothelial growth factor inhibitors or corticosteroids therapies), and surgical removal are currently available. Although laser has been considered as the gold standard for many years, over the past several years vascular endothelial growth factor inhibitors (anti-VEGFs) have become first-line therapy. However, many patients do not adequately respond to them. With the development of sustained-release corticosteroid devices, steroids have gained a presence in the management of the DME. We review and update the role of anti-VEGF and intravitreal sustained-release corticosteroid management of DME. According to the currently available scientific evidence, the choice of one anti-VEGF over another critically depends on the baseline best-corrected visual acuity (BCVA). While aflibercept may be the drug of choice in low baseline BCVA, the three anti-VEGFs (bevacizumab, ranibizumab, and aflibercept) provided similar functional outcomes when the baseline BCVA was higher. DEX implants are a valuable option for treating DME, although they are usually seen as a second choice, particularly in those eyes that have an insufficient response to anti-VEGF. The new evidence suggested that, in eyes that did not adequately respond to anti-VEGF, switching to a DEX implant at the time to 3 monthly anti-VEGF injections provided better functional outcomes.

Saudi Arabia Guidelines for diabetic macular edema: A consensus of the Saudi Retina Group

Diabetes mellitus (DM) and its complications are major public health burdens in Saudi Arabia. The prevalence of diabetic retinopathy (DR) is 19.7% and the prevalence of diabetic macular edema (DME) is 5.7% in Saudi Arabia. Diabetic macular edema is a vision-threatening complication of DR and a major cause of vision loss worldwide. Ocular treatments include retinal laser photocoagulation, anti-vascular endothelial growth factor (anti-VEGF) agents, intravitreal corticosteroids, and vitreoretinal surgery when necessary. The present consensus was developed as a part of the Saudi Retina Group's efforts to generate Saudi guidelines and consensus for the management of DME, including recommendations for its diagnosis, treatment, and best practice. The experts' panel stipulates that the treatment algorithm should be categorized according to the presence of central macula involvement. In patients with no central macular involvement, laser photocoagulation is recommended as the first-line option. Patients with central macular involvement and no recent history of cardiovascular (CVS) or cerebrovascular disorders can be offered anti-VEGF agents as the first-line option. In the case of non-responders (defined as an improvement of <20% in optical coherence tomography or a gain of fewer than 5 letters in vision), switching to another anti-VEGF agent or steroids should be considered after 3 injections. Within the class of steroids, dexamethasone implants are recommended as the first choice. In patients with a recent history of CVS events, the use of anti-VEGF agents is not recommended, regardless of their lens status. The experts' panel recommends that a future study be conducted to provide a cut-off point for early switching to steroid implants in pseudo-phakic eyes.

Efficacy and safety of intravitreal dexamethasone implant in treatment naïve eyes with diabetic macular edema: Real world experience

PURPOSE

To evaluate the efficacy and safety of intravitreal dexamethasone implant in treatment naïve eyes with diabetic macular edema (DME).

METHODS

A retrospective analysis of treatment naïve eyes with DME which received intravitreal dexamethasone implant between January 2016 and March 2018 was done. Demographic details of the patients, ocular examination findings at baseline and on follow up visits were noted. Morphological features of DME and central macular thickness were noted on optical coherence tomography at each visit. The details regarding additional treatment for macular edema on follow up were noted.

RESULTS

Sixty five eyes were included in the study. The mean age was 59.14 ± 9.59 years. The follow up ranged from 6 to 48 months. Psuedophakic eyes showed visual improvement whereas the phakic eyes showed stable vision. The central foveal thickness showed significant reduction (p = 0.05) in all the eyes. The best corrected visual acuity at final follow up (+0.65 logMAR) was slightly less as compared to baseline (+0.62 logMAR). Retreatment was needed in 37% eyes and antiglaucoma medications in 8% eyes. Cataract progression was noted in 24 eyes (37%); 17 eyes (26.1%) underwent surgery. Notably, 27 eyes (41.5%) had some degree of macular ischemia at baseline. And five eyes (7.7%) showed progression of retinopathy leading to vitreous hemorrhage.

CONCLUSION

Dexamethasone implant is helpful in reducing the macular thickness and stabilizing the vision in treatment naïve DME; requiring less number of treatment sessions. However, it does not prevent progression of diabetic retinopathy. The visual improvement may be affected by cataract and macular ischemia.

Intravitreal Dexamethasone Implant as a Sustained Release Drug Delivery Device for the Treatment of Ocular Diseases: A Comprehensive Review of the Literature

Drug delivery into the vitreous chamber remains a great challenge in the pharmaceutical industry due to the complex anatomy and physiology of the eye. Intravitreal injection is the mainstream route of drug administration to the posterior segment of the eye. The purpose of this review is to assess the current literature about the widening use of the intravitreal 0.7 mg dexamethasone (Dex) implant, and to provide a comprehensive collection of all the ocular disorders that benefit from Dex administration. Although anti-vascular endothelial growth-factors (VEGFs) have been largely indicated as a first-choice level, the Dex implant represents an important treatment option, especially in selected cases, such as vitrectomized eyes or patients in whom anti-VEGF failed or are contraindicated. In this article, the safety profile as well as the list of the possible complications related to intravitreal Dex injection are also discussed.

Drug Tissue Distribution of TUDCA From a Biodegradable Suprachoroidal Implant versus Intravitreal or Systemic Delivery in the Pig Model

Purpose

To determine local ocular tissue levels of the bile acid, tauroursodeoxycholic acid (TUDCA), in the pig model using oral, intravenous (IV), intravitreal injection (IVitI) and low- and high-dose suprachoroidal, sustained-release implants (SCI-L or SCI-H).

Methods

Forty-six pigs (92 globes) were included in the study. TUDCA was delivered orally in 5 pigs, IV in 4, IVitI in 6, SCI-L in 17, and SCI-H in 14. Testing timeframes varied from the same day (within minutes) for IV; 1 to 6 days, oral; and 1 to 4 weeks, IVitI and SCI. Enucleated globes were dissected, specimens from specific tissues were separated, and TUDCA was extracted and quantified using mass spectrometry.

Results

The highest TUDCA tissue levels occurred after IV delivery in the macula (252 ± 238 nM) and peripheral retina (196 ± 171 nM). Macular choroid and peripheral choroid levels were also high (1032 ± 1269 and 1219 ± 1486 nM, respectively). For IVitI delivery, macular levels at day 6 were low (0.5 ± 0.5 nM), whereas peripheral choroid was higher (15.3 ± 16.7 nM). Neither the SCI-L nor SCI-H implants delivered meaningful macular doses (≤1 nM); however, peripheral retina and choroid levels were significantly higher. Bile acid isoforms were found in the serum specimens.

Conclusions

The highest TUDCA tissue levels in the pig model were obtained using IV delivery. Oral delivery was associated with reasonable tissue levels. Local delivery (IVitI and SCI) was able to achieve measurable local ocular tissue levels.

Translational Relevance

Diffusional kinetics from the suprachoroidal space follow the choroidal blood flow, away from the macula and toward the periphery.

Real-Life Management of Diabetic Macular Edema with Dexamethasone Intravitreal Implant: A Retrospective Analysis of Long-Term Clinical Outcomes

PURPOSE

Inflammation plays a key role in the pathogenesis of diabetic macular edema (DME), and intravitreal corticosteroids are among the recommended therapies. The goal of this retrospective analysis was to describe outcomes with dexamethasone intravitreal implant (DEX implant) in real life.

METHODS

Medical digital records of DME patients treated with DEX implant and followed up for 3 years were analyzed. Treatment with DEX implant was started either as first-line therapy in pseudophakic patients and in patients with cardiovascular comorbidities or as second-line therapy in patients refractory to the inhibitor of the vascular endothelial growth factor (anti-VEGF) therapy. Analyzed outcomes included central macular thickness (CMT) and best-corrected visual acuity (BCVA). Mean number of implant injections per patient and mean duration of the interval between injections were also estimated.

RESULTS

Seventy-five patients (mean age 65.7 (±12.3) years; 53 phakic and 22 pseudophakic) with DME were included. Overall, 84 eyes were treated. Mean CMT improved from 380.1 (±100.3) µm at baseline to 306.8 (±77.0) µm at 36 months (p=0.0003). Mean BCVA improved for up to 6 months (p=0.08) and then started to decrease reaching values lower than baseline after 24 months. In pseudophakic patients, BCVA improvements were more pronounced and sustained up to 36 months (p=0.6). Over 36 months, each patient received on average 2.4 (±1.6) intravitreal injections of DEX implant. The time interval between consecutive injections was included between 180 and 240 days. No unexpected safety issues were reported.

CONCLUSIONS

With fewer than 3 injections per patient over a 3-year period, DEX implant was able to improve anatomic outcomes in DME patients. Only pseudophakic eyes showed also a long lasting functional benefit at 36 months.

Real-world experience with pro re nata dosing of intravitreal dexamethasone implant for eyes with refractory diabetic macular edema

Aims: To evaluate treatment outcomes of pro re nata dosing of intravitreal dexamethasone implant in eyes with refractory diabetic macular edema (DME) amongst Indian subjects.

Methods and material: Retrospective, interventional case series. Medical records of 28 eyes of 23 patients with refractory DME who underwent intravitreal dexamethasone (700 µ) implant were reviewed.

Paired t-test was carried out to measure mean change in the parameters evaluated. Mann-Whitney U test and Fisher’s exact t-test were done to explore differences between groups receiving single or multiple injections.

Results: Best corrected visual acuity (BCVA) and central macular thickness (CMT) at baseline were 0.85 (±0.44) and 612 µm (±123), respectively. Mean CMT over 6 months (measured monthly) following injection was 340±119 µm (p=0.001), 346±150 µm (p=0.02), 368±169 µm (p=0.02), 304±174 µm (p=0.001), 525±216 µm (p=0.94) and 532±201 µm (p=0.46), respectively. Mean BCVA at each month following injection was 0.68±0.36 (p=0.02), 0.75±0.45 (p=0.42), 0.55±0.40 (p=0.11), 0.63±0.40 (p=0.12), 0.78±0.30 (p=0.90) and 0.60±0.47 (p=0.92), respectively. Mean follow-up was 12 months (range: 6–33 months). Mean BCVA and CMT at mean 12 months were 0.72±0.46 (p=0.10) and 358 µm±189 (p=0.0001), respectively. Seven eyes had raised IOP; five eyes required cataract extraction.

Conclusions: Intravitreal dexamethasone implant is effective in treatment of refractory DME. However, its therapeutic effect lasts for about 4 months.

Local delivery of corticosteroids in clinical ophthalmology: A review

Locally administered steroids have a long history in ophthalmology for the treatment of inflammatory conditions. Anterior segment conditions tend to be treated with topical steroids whilst posterior segment conditions generally require periocular, intravitreal or systemic administration for penetration. Over recent decades, the clinical applications of periocular steroid delivery have expanded to a wide range of conditions including macular oedema from retino-vascular conditions. Formulations have been developed with the aim to provide practical, targeted, longer-term and more efficacious therapy whilst minimizing side effects. Herein, we provide a comprehensive overview of the types of periocular steroid delivery, their clinical applications in ophthalmology and their side effects.

Diabetic Macular Edema: State of Art and Intraocular Pharmacological Approaches

Diabetic macular edema (DME) is the main cause of vision loss in diabetic retinopathy (DR). Although it is one of the main complications of diabetes, the pathogenesis of DME is not completely understood. The hyperglycemic state promotes the activation of multiple interlinked pathways leading to DME. Different classifications have been proposed: based on clinical features, on pathogenesis or on diagnostic tests (optical coherence tomography - OCT and fluorescin angiography - FA). The multimodal imaging allows a better analysis of the morphological features of the DME. Indeed, new inflammatory biomarkers have been identified on OCT. Also, several studies are evaluating the role of the morphological features, identified on multimodal imaging, to find new prognostic factors. Over the past decade, great progresses have been made in the management of DME. Therapeutic alternatives include intraocular injection of anti-vascular endothelial grow factor agents (anti-VEGF) and steroid molecules, focal/grid laser photocoagulation and vitreo-retinal surgery. This review is focused on the description and analysis of the current intravitreal therapeutic pharmacological strategies. Current guidelines recommend anti-VEGF as first line therapy in DME. Corticosteroids are becoming increasingly relevant blocking the inflammatory cascade and indirectly reducing VEGF synthesis.

Corticosteroids for Diabetic Macular Edema

Diabetic macular edema (DME) is a chronic condition with a multifactorial pathogenesis. Vascular endothelial growth factor (VEGF) and several inflammatory mediators are upregulated in eyes with DME. VEGF inhibitors and corticosteroids have all been used successfully in the management of DME. Currently available corticosteroids include triamcinolone acetonide (TA), the dexamethasone (DEX) intravitreal implant, and the fluocinolone acetonide (FA) intravitreal implant. The response to treatment can vary substantially with each treatment modality. Some cases of DME are VEGF driven, and in others, inflammation plays a key role. Chronicity appears to favor corticosteroid treatment. There are no clear guidelines to guide switching from an anti-VEGF to a corticosteroid. Combination therapy of an anti-VEGF drug and a corticosteroid does not appear to provide additional benefit over monotherapy with either drug. The main advantage of corticosteroids over VEGF inhibitors is their longer duration of action. Vitrectomy does not affect the pharmacokinetics of the corticosteroid implants. Common adverse events of corticosteroids include cataract formation, cataract progression, and ocular hypertension. TA may cause a sterile endophthalmitis and pseudoendophthalmitis. Migration of the intravitreal DEX and FA implants into the anterior chamber can be problematic. Because of their less favorable safety profile, corticosteroids are generally used as a second-line treatment for DME. Advantages of using an intravitreal corticosteroid implant include the reduction of treatment burden and predictable pharmacokinetics even in vitrectomized eyes. Pseudophakic eyes, previously vitrectomized eyes and eyes with long-standing DME, particularly of patients who have difficulty in maintaining a monthly appointment, may benefit from primary treatment with a corticosteroid intravitreal implant.

Intravitreal dexamethasone implant Ozurdex in the treatment of diabetic macular edema in patients not previously treated with any intravitreal drug: a prospective 12-month follow-up study

Objective: To evaluate the mid-long-term efficacy and safety of the dexamethasone intravitreal (DEX) implant (Ozurdex¹) in naïve patients with diabetic macular edema (DME).Methods: Prospective and single-center study conducted on consecutive patients with a diagnosis of DME, who received a DEX implant and were followed up for at least 12 months. The main outcomes measurements were the mean change in best corrected visual acuity (BCVA) and in foveal thickness (FT) as compared to the baseline values.Results: Of the 84 screened patients 50 were included in the study. The BCVA significantly improved from 52.4 (20.4) letters at baseline to 62.6 (15.6), 61.2 (18.4), 61.6 (18.6), 60.6 (19.0), and 60.6 (18.8) at 2, 4, 6, 12 months and end of follow-up period, respectively (repeated measures ANOVA and the Greenhouse-Geisser correction; p = .0008). At the end of the follow-up period, a gain of BCVA of ≥5, ≥10, and ≥15 letters were observed in 26 (52.0%), 18 (36.0%), and 16 (32.0%) patients, respectively. The mean FT was significantly reduced from 446.0 (139.9) µm at baseline to 327.2 (103.6) at the end of follow-up (repeated measures ANOVA and the Greenhouse-Geisser correction; p = .0008). During the study follow-up, the patients receive a mean of 3.4 (2.9-3.9) implants. Of the 32 phakic eyes at baseline, 17 (53.1%) either developed new lens opacity or progression of an existing opacity.Conclusion: In eyes with DME not previously treated with intravitreal drugs, DEX implants provide meaningful functional and anatomical benefits, and these results are sustained mid-long-term.

A Collaborative Retrospective Study on the Efficacy and Safety of Intravitreal Dexamethasone Implant (Ozurdex) in Patients with Diabetic Macular Edema: The European DME Registry Study

PURPOSE

To evaluate the efficacy, effect profile, and safety of dexamethasone implant on diabetic macular edema (DME) in a real-life setting, further comparing results by DME duration, previous treatment status, and diabetic control.

DESIGN

A multicenter, retrospective cohort of 340 DME eyes of 287 patients from 25 clinical sites from 8 countries.

METHODS

Data were analyzed in 2 perspectives: per injection, in which all measurements were grouped and baseline was defined as the day of injection, and thus the pharmacodynamics of single injections could be assessed; and injection series, defined as 2 or more injections with 3 to 6 months between injections analyzing the outcome 3 to 6 months after the last injection.

MAIN OUTCOME MEASURES

Primary outcome was improvement of 15 or more letters in best-corrected visual acuity (BCVA) from baseline. Secondary outcomes included improvement of 10 letters or more in BCVA, change in central macular thickness (CMT), and time to maximum improvement and safety.

RESULTS

Overall, 762 injections were administered to 340 eyes of 287 patients. Injection series analysis included 171 series in 171 eyes of 150 patients, for a total of 444 injections, with a mean follow-up of 1.7±0.8 years. Of the 762 injections analyzed per injection, 22.7% achieved a 15-letter or more improvement, and 37.8% achieved a 10-letter or more improvement. Mean time to peak improvement was 81.9±39.7 days. Mean maximum change in CMT was -174±171 μm. Overall, 7.6% lost 15 or more letters. More eyes with early DME gained 10 or more letters and fewer eyes lost 10 or more letters compared with eyes with late DME (47.4% vs. 33.9% [P = 0.001] and 8.2% vs. 13.5% [P = 0.029], respectively). Patients with controlled diabetes showed greater CMT reduction (P = 0.0002). A higher percentage of treatment-naive patients gained 10 or 15 letter or more in BCVA (P = 0.001 and P = 0.006, respectively). Intraocular pressure elevation of more than 25 mmHg was found following 7.9% of injections; no endophthalmitis was reported.

CONCLUSIONS

Dexamethasone implant is an effective and safe treatment for DME. Peak improvement was achieved 3 months after injection and dissipated thereafter. Clinicians and providers may consider shortening treatment intervals.