Dexamethasone implant with fixed or individualized regimen in the treatment of diabetic macular oedema: six-month outcomes of the UDBASA study

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.

Healthcare expenditure of intravitreal anti-vascular endothelial growth factor inhibitors compared with dexamethasone implant for diabetic macular oedema

PURPOSE

The aim of this study was to estimate the 1-year costs associated with treating diabetic macular oedema (DME) patients using current intravitreal anti-vascular endothelial growth factor (anti-VEGF) biologics compared with the dexamethasone implant.

METHODS

We conducted a descriptive cost-evaluation analysis using data from Oslo University Hospital and literature to compare three different intravitreal drugs for DME: bevacizumab, aflibercept and dexamethasone. Stratification of patients into 'Naive' or 'Switch' group was based on treatment history. We estimated the costs from healthcare and 'extended' healthcare perspectives. Sensitivity analysis evaluated the impact of various parameters.

RESULTS

The average injections per patient per year for the Naive group (bevacizumab), Switch group (aflibercept) and dexamethasone were 9.5, 9.1 and 3.0 respectively. From a healthcare perspective, the 1-year costs for the Naive group were 15% lower (bevacizumab, €3619), and for the Switch group, 23% higher (aflibercept, €5226) compared with dexamethasone (€4252). The 'extended' healthcare perspective showed the cost per patient per year for bevacizumab remained nominally lower in the Naive group, while dexamethasone remained lower for the Switch group (€5116 for dexamethasone, compared to €4987 for bevacizumab and €6537 for aflibercept).

CONCLUSIONS

From a primary healthcare perspective, the dexamethasone as a first-line DME treatment may increase economic costs in settings where bevacizumab is used off-label. Treating resistant DMEwith dexamethasone may reduce the costs and treatment burden compared with switching to aflibercept.

Effect of intravitreal dexamethasone implant in treatment-naive and previously-treated patients with diabetic macular edema

PURPOSE

To document the effects of intravitreal dexamethasone implant on retinal microvasculature in patients with diabetic retinopathy complicated by center-involving macular edema.

METHODS

35 eyes of 35 patients affected by retinopathy due to type 2 diabetes (15 treatment-naïve and 20 previously treated) were included in this retrospective study with a follow-up of 4 months. Foveal avascular zone (FAZ) area and superficial capillary plexus (SCP) and deep capillary plexus (DCP) densities in the foveal and parafoveal areas were measured by optical coherence tomography angiography (OCTA) at baseline and 2 and 4 months post-injection. Intraocular pressure, morphological and functional parameters were evaluated.

RESULTS

a significant difference was found in both groups at 2 months after injection in terms of functional (BCVA, p < 0.05) and morphological (CMT, p < 0.05) parameters. During follow-up, FAZ area, SCP, and DCP in the foveal and parafoveal areas did not change significantly.

CONCLUSIONS

intravitreal dexamethasone implant is effective in the treatment of diabetic center-involving macular edema and was associated with significant improvements in BCVA and CMT at 2 months after injection. After a single dexamethasone implant injection, FAZ area and retinal vascular density does not show significant variations in both naive and non-naive DME patients subgroups.

Effectiveness of a Hydrophilic Curcumin-Based Formulation in Coadjuvating the Therapeutic Effect of Intravitreal Dexamethasone in Subjects With Diabetic Macular Edema

Purpose: This study evaluates if the addition of a curcumin formulation with a polyvinylpyrrolidone-hydrophilic carrier (CHC; Diabec^®, Alfa Intes, Italy) to intravitreal injections of dexamethasone (DEX-IVT) can affect the morphological retinal characteristics, extending the steroid re-treatment period in patients with diabetic macular edema (DME).

Methods: A randomized controlled clinical trial was carried out in DME patients, randomly assigned to receive DEX-IVT or DEX-IVT and a CHC. The evaluation of the mean difference of central retinal thickness (CRT) was the primary aim. Secondary aims were the evaluations of best-corrected visual acuity, differences in the predetermined retinal layer thickness, the number/time of re-treatment, and the assessment of safety.

Results: A total of 73 DME patients were included (35 in the control group and 38 in the combined therapy group). In both the control and combined therapy groups, the mean CRT change from T₀ to the 6 months’ evaluation was significant (p = 0.00). The mean CRT result was significantly different at month 4 (p = 0.01) between the control and combined therapy groups, with a greater reduction in the combined therapy group, in particular, in patients with ≤10 years of diabetes. A trend of CRT reduction in the combined therapy group has been observed also considering patients with subfoveal neuroretinal detachment. In addition, we observed that the reduction of inner retinal layer thickness was greater in the combination group, in comparison with controls.

Conclusion: The combination of a CHC to DEX-IVT is a promising therapeutic option in case of DME, in particular, for patients with early-stage diabetes and with an inflammatory phenotype. Further studies will be necessary to confirm these findings.

Recommendations for the management of diabetic macular oedema with intravitreal dexamethasone implant: A national Delphi consensus study

PURPOSE

The intravitreal dexamethasone implant (DEX-I) is an alternative to anti-VEGF for the first-line treatment of diabetic macular oedema (DME). However, several questions remain regarding its routine use and its place in certain situations not always specified in current recommendations. A national consensus approach was, therefore, initiated by French retinal experts.

METHODS

An iterative Delphi consensus approach was used. A steering committee (SC) of seven experts analysed data from the literature to formulate statements divided into five key areas of treatment. These statements were submitted to the independent and anonymous electronic vote of 87 French retina experts among whom 39 expressed their opinion and therefore constituted the voting panel.

RESULTS

After two rounds of voting, 22 and 7 of 38 statements received a strong consensus and a good consensus, respectively. The consensus level was higher for statements regarding first-line indications and safety of DEX-I compared to those regarding efficacy assessment, reprocessing time or pathophysiological biomarkers. The panellists recommended the preferential use of DEX-I for patients with limited availability for multiple injections, those who needed to undergo cataract surgery or who had a recent cardiovascular history, and as a therapeutic alternative to anti-VEGF in patients with a history of vitrectomy, retinal serous detachment, hyper-reflective points or dry exudates in optical coherence tomography (OCT). However, some statements proposed by SC experts were not validated.

CONCLUSION

This study provides some key recommendations to clinicians treating diabetic macular oedema, which may be useful when using intravitreal dexamethasone implants in daily practice.

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.

Managing Diabetic Macular Edema in Clinical Practice: Systematic Review and Meta-Analysis of Current Strategies and Treatment Options

Purpose

This meta-analysis aims to summarize 12-month best-corrected visual acuity (BCVA) outcomes in response to anti-vascular endothelial growth factor (VEGF) therapy and dexamethasone implant for the treatment of diabetic macular edema (DME) and to identify factors affecting treatment response using evidence generated from meta-regression.

Methods

A systematic review of electronic databases was conducted to identify randomized controlled trials (RCTs) and real-life/observational studies that reported 12-month changes in BCVA in patients with DME on anti-VEGF or dexamethasone implant treatment in monotherapy. Study factors that were analyzed are baseline patient characteristics, study type, drug employed, number of injections and 12-month change in BCVA. Data were pooled in a random-effects meta-analysis with BCVA change as the main outcome. Meta-regression was conducted to assess the impact of multiple covariates.

Results

One-hundred-five heterogeneous study populations (45,032 eyes) were identified and included in the analysis. The use of anti-VEGFs and dexamethasone implant induced an overall increase of +8.13 ETDRS letters in BCVA at 12 months of follow-up. Meta-regression provided evidence that mean BCVA change using anti-VEGFs was not statistically higher for RCTs (p=0.35) compared to observational studies. Dexamethasone implant showed a trend for better results in observational studies over RCTs. Populations following a fixed aflibercept regimen performed better than those following a reactive treatment regimen. Mean BCVA gain was higher in younger populations (p<0.001), with lower baseline BCVA (p<0.0001) and longer diabetes duration (p<0.0001), receiving a higher number of injections (p<0.0001).

Conclusion

Intravitreal therapy with anti-VEGFs or dexamethasone implant produces a significant improvement in BCVA at 12 months in patients with DME. Meta-regression identified the modifiable covariates that can be targeted in order to maximize functional results.

A Real-World Study of Dexamethasone Implant in Treatment-Naïve Patients with Diabetic Macular Edema: Efficacy and Correlation Between Inflammatory Biomarkers and Treatment Outcome

Purpose

There has been an increasing clinical interest in specific retinal parameters as non-invasive biomarkers of retinal inflammation in diabetic macular edema (DME) that have been shown to have prognostic value, such as hyperreflective retinal fields (HRFs) and subfoveal neuroretinal detachment (SND).

Methods

We conducted a prospective, non-comparative study of treatment-naïve patients with DME to evaluate the efficacy of a Pro Re Nata (PRN) regimen of intravitreal dexamethasone implant 0.7 mg (DexI, Ozurdex™). After administration, patients underwent subsequent injections according to PRN criteria in case of edema relapse, but not earlier than 4 months after the previous treatment. Patients were evaluated at baseline, within 15 days of injection, and every month thereafter. During all visits, best-corrected visual acuity (BCVA) was recorded; central retinal thickness (CRT), type of edema, presence of SND, and presence and number of HRFs were evaluated using swept-source optical coherence tomography (SS-OCT) 3D. Treatment outcome was defined as changes in BCVA, CRT, SND and HRFs at 12 (T12) and 24 (T24) months compared with baseline (T0).

Results

The study enrolled 24 eyes of 18 patients. The mean duration of follow-up was 18±6.6 months; for all eyes, T12 data were available, while follow-up reached T24 for 12 eyes. BCVA improved significantly and CRT decreased significantly during treatment; the edema was no longer detectable in 13/24 eyes at T12 and 8/12 eyes at T24. No patient presented SND at T12 and T24, and the mean number of HRFs decreased significantly during treatment. Results with CRT and HRFs correlated with BCVA at 12 and 24 months. No significant adverse events were observed.

Conclusion

In patients with DME, the intravitreal dexamethasone implant was effective and safe in improving both functional and tomographic parameters. This result is consistent with improvement in biomarkers of inflammation.

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.

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.

Dexamethasone implant in the management of diabetic macular edema from clinician's perspective

The aim of this article is to provide an overview of characteristics and principles of use of dexamethasone implant in patients with diabetic macular edema (DME). The condensed information about patient selection, dosing, and postinjection management is provided to make the clinician’s decisions easier in real-life practice. DME is a common complication of diabetes and the leading cause of visual loss in the working-age population. Inflammation plays an important role in the pathogenesis of DME. The breakdown of the blood–retinal barrier involves the expression of inflammatory cytokines and growth factors, including vascular endothelial growth factor (VEGF). Steroids have proved to be effective in the treatment of DME by blocking the production of VEGF and other inflammatory cytokines, by inhibiting leukostasis, and by enhancing the barrier function of vascular endothelial cell tight junctions. Dexamethasone intravitreal implant has demonstrated efficacy in the treatment of DME resistant to anti-VEGF therapy and in vitrectomized eyes. Data from clinical trials suggest that dexamethasone implant can be considered as first-line treatment in pseudophakic eyes. Dexamethasone implant is also the first-line therapy in patients not suited for anti-VEGF therapy, pregnant women, and patients unable to return for frequent monitoring. It has been shown that the maximum effect of dexamethasone implant on visual gain and retinal thickness occurs approximately 2 months after injection. Various treatment regimens are used in real-life situations, and reported reinjection intervals were usually <6 months. The number of retreatments needed decreased over time. Treatment algorithms should be personalized. Postinjection management and follow-up should consider potential adverse events such as intraocular pressure elevation and cataract.

Long-term efficacy and safety profile of multiple injections of intravitreal dexamethasone implant to manage diabetic macular edema: A systematic review of real-world studies

INTRODUCTION

Systematic review of real-world studies about repeated dexamethasone intravitreal implant (DEXi) 0.7 mg in diabetic macular edema management, in order to identify the effective window of time occurring between injections, the critical evaluation of efficacy of the treatment, and the relative long-term safety in the real life setting.

METHODS

Literature databases such as PubMed, SCOPUS, and EMBASE were used to identify reports including DEX implant injections.

RESULTS

Twenty-one peer-reviewed publications were identified. DEX implants retreatment was considered on a pro re nata (PRN) basis at any time or starting from month three or four. About 1/3 of the eyes were retreated before six months from first injection (range 0-86.7%). Mean retreatment average time was 5.3 ± 0.9 months, with an estimated average of 1.3 injections each six months. There was no statistical correlation between average retreatment time and incidence of adverse events or other variables investigated. Limited safety issues related to implants number have been found, suggesting an overall good tolerance of long-term DEXi.

CONCLUSIONS

Comprehensive evaluation of real-world data suggests an average DEXi duration close to five months, following a PRN treatment strategy, including about 1/3 of patients. Repeated DEXi administration revealed an acceptable long-term efficacy/safety ratio.

Polyester elastomers for soft tissue engineering

Polyester elastomers are soft, biodegradable and biocompatible and are commonly used in various biomedical applications, especially in tissue engineering. These synthetic polyesters can be easily fabricated using various techniques such as solvent casting, particle leaching, molding, electrospinning, 3-dimensional printing, photolithography, microablation etc. A large proportion of tissue engineering research efforts have focused on the use of allografts, decellularized animal scaffolds or other biological materials as scaffolds, but they face the major concern of triggering immunological responses from the host, on top of other issues. This review paper will introduce the recent developments in elastomeric polyesters, their synthesis and fabrication techniques, as well as their application in the biomedical field, focusing primarily on tissue engineering in ophthalmology, cardiac and vascular systems. Some of the commercial and near-commercial polyesters used in these tissue engineering fields will also be described.

Management of diabetic macular edema with intravitreal dexamethasone implants: Expert recommendations using a Delphi-based approach

OBJECTIVES:

Despite being approved and effective, steroids, and especially dexamethasone intravitreal implants, still have a poorly-defined role in management of diabetic macular edema. In order to overcome some of the limitations in current recommendations, a group of experts met to define consensus on some of the most controversial issues on the use of dexamethasone intravitreal implants in daily management of diabetic macular edema.

METHODS:

A Delphi-based approach was utilized to develop clinically relevant statements applicable to routine treatment settings. A Steering Committee composed of four experts formulated 30 relevant statements, which were voted upon by a panel of 40 ophthalmologists/retinal specialists from across Italy.

RESULTS:

Dexamethasone intravitreal implants were considered to be a valid first-line alternative to treatment with an anti-vascular endothelial growth factor agent and should be the first choice in pseudophakic and vitrectomized patients. A Pro Re Nata regimen was felt to be appropriate for retreatment with dexamethasone intravitreal implants while a 6-month waiting period was not considered suitable. Among steroid treatments, dexamethasone intravitreal implants were considered to have the best ocular tolerability. In patients with persistent macular edema after the loading-phase treatment with an anti-vascular endothelial growth factor, consensus was reached that clinicians should consider switching therapy to dexamethasone intravitreal implants. Moreover, dexamethasone intravitreal implants can reduce the treatment burden for individuals who are not able to cope with the more intensive treatment regimen required by anti-vascular endothelial growth factor therapy.

CONCLUSIONS:

While further studies are needed, this survey provides some key recommendations for clinicians treating diabetic macular edema that may be useful when choosing dexamethasone intravitreal implants in daily practice.

Fluocinolone acetonide for the treatment of diabetic macular edema

INTRODUCTION

Fluocinolone acetonide intravitreal implant is a non-erodible implant approved for the treatment of diabetic macular edema (DME) insufficiently responsive to available therapies. Areas covered: The injectable intravitreal implant releases fluocinolone acetonide at an average rate of 0.2 µg/day for at least 36 months. The two pooled pivotal FAME trials showed that, in patients with DME previously treated with laser photocoagulation, fluocinolone acetonide intravitreal implant was more beneficial than sham injection when looking at the proportion of patients with an improvement from baseline in visual acuity of more than 15 letters at 24 months and at 36 months. Cataract (82%) and intraocular pressure (IOP) elevation (37%) were the most common adverse events. Raised IOP was mostly treated with IOP-lowering medications, with <5% of eyes requiring incisional IOP-lowering surgery. FAME trial program results are confirmed by a series of real-world studies in eyes with chronic/recalcitrant DME. Expert opinion: data indicate that fluocinolone acetonide intravitreal implant is a useful second-line option for the treatment of DME.