Effect of Adding Dexamethasone to Continued Ranibizumab Treatment in Patients With Persistent Diabetic Macular Edema: A DRCR Network Phase 2 Randomized Clinical Trial

Visual and anatomic outcomes of sustained single agent anti-VEGF treatment versus double anti-VEGF switching in the treatment of persistent diabetic macular edema

Background

To compare the anatomical and visual outcomes in eyes with persistent diabetic macular edema (DME) after initial anti-VEGF therapy that were retreated continuously with the same anti-VEGF drug versus those that underwent two successive cycles of medication change in anti-VEGF drugs (double anti-VEGF switch).

Methods

Retrospective review of eyes with persistent DME after 3 initial consecutive monthly anti-VEGF injections. This cohort was divided into two groups: Group 1 continued to receive the same initial anti-VEGF drug for at least 18 months while group 2 eyes were switched to different anti-VEGF medications twice. Group 1 was further subdivided into: Group 1A composed of eyes with less than 20% reduction in central subfield thickness (CRT) at month 3; and group 1B eyes with greater than or equal to 20% reduction in CRT. The percentage of eyes that achieved greater than 10 letters visual acuity (VA) gain or loss was recorded as the primary end point (through month 18 in group 1 and month 6 after 2nd switch in group 2).

Results

Group 1A, 1B and group 2 were composed of 24, 18, and 14 eyes respectively. 34.7%, 56.2% and 36.3% of eyes achieved > 10 letters gain, while 4.3%, 6.2% and 27.2% of eyes lost > 10 letters in groups 1A, 1B, and 2, respectively. Analysis of the visual acuity (VA) letter change in this time interval revealed no significant difference between all groups (p = 0.11). Mean VA and CRT measurements at the primary endpoint in all groups were 0.5, 0.39, and 0.47 logMAR (p = 0.44), and 369.7, 279.9, 321 µm, (p = 0.01) respectively.

Conclusions

There was no difference in the visual outcomes between the two treatment strategies in eyes with persistent DME after 3 consecutive anti-VEGF injections. This may indicate that anti-VEGF switching—even if it is done twice—may have comparable clinical outcomes to sustained treatment with one agent.

Results of dexamethasone intravitreal implant (Ozurdex) in diabetic macular edema patients: Early versus late switch

PURPOSE

To assess the functional and anatomical outcomes of intravitreal dexamethasone implant Ozurdex® in eyes with diabetic macular edema that did not adequately respond to vascular endothelial growth factor inhibitors.

METHODS

Multicenter, retrospective, and real-life case series study conducted on consecutive diabetic macular edema patients who underwent treatment with one or more dexamethasone implant injections and were followed up for a minimum of 12 months. Subjects were divided into three groups: I-naïve patients, II-previously treated eyes that received three intravitreal antivascular endothelial growth factor inhibitors injections before the study (early switch), and III-previously treated eyes that received >3 intravitreal antivascular endothelial growth factor inhibitors injections before the study (late switch). Primary endpoints were best-corrected visual acuity and central retinal thickness at month 12.

RESULTS

A total of 129 eyes (21 naïve and 108 previously treated, Group II: 32 and Group III: 76) were included. At month 12, best-corrected visual acuity significantly improved from 0.27 ± 0.23 and 0.31 ± 0.22 at baseline to 0.36 ± 0.25 and 0.37 ± 0.23 at month 12 in naïve and previously treated eyes, respectively, and p = 0.0063 and 0.0060, respectively. Central retinal thickness, in naïve and previously treated eyes, was significantly reduced from 483.0 ± 143.4 and 431.3 ± 115.5 µm, at baseline, to 278.8 ± 72.1 and 269.3 ± 66.2 µm, at month 12, respectively, and p < 0.0001 each, respectively. Best-corrected visual acuity improvement was significantly greater in both absolute and percentage values, p = 0.0393 and 0.0118, respectively, in Group II than in Group III.

CONCLUSION

In eyes with insufficient response to antivascular endothelial growth factor inhibitors, switching to dexamethasone at the time to 3-monthly antivascular endothelial growth factor inhibitors injections provided better functional outcomes than those that received >3 antivascular endothelial growth factor inhibitors injections.

Aqueous humour cytokine changes during a loading phase of intravitreal ranibizumab or dexamethasone implant in diabetic macular oedema

PURPOSE

To determine the effect of intravitreal ranibizumab and a dexamethasone implant on aqueous humour cytokine, protein and enzyme levels and to correlate findings to morphologic and functional changes.

METHODS

In a prospective, randomized, controlled, double-blind study, patients with clinically significant diabetic macular oedema (CSME) were randomly allocated to receive either monthly intravitreal injections of ranibizumab (Lucentis, Novartis Pharma) or a single dexamethasone implant (Ozurdex, Pharm-Allergan) at baseline (BL). Aqueous humour samples were collected at BL and weeks 2, 8 and 20.

RESULTS

The study included 18 eyes of 18 patients. In the dexamethasone implant group, soluble intercellular adhesion molecule 1 (sICAM-1) (weeks 2 and 8), CXCL9/monokine induced by gamma interferon (MIG) (weeks 2 and 8), soluble vascular cell adhesion protein 1 (sVCAM-1) (weeks 2 and 8) and monocyte chemo-attractant protein 1 (MCP-1) (week 2) levels were significantly decreased compared with baseline. In the ranibizumab group, placental growth factor (PIGF) (week 2) and vascular endothelial growth factor (VEGF) (week 2 and 8) levels were significantly decreased compared with baseline. No significant changes in central retinal thickness (CRT) or Early Treatment Diabetic Retinopathy Study (ETDRS) best corrected visual acuity (BCVA) were observed in the Ozurdex group at any time-points. ETDRS scores significantly increased at week 20 (84.88 ± 8.88 letters) compared with baseline (74.78 ± 14.85 letters), and the CRT decreased significantly at week 4 (381.00 ± 114.64 μm) compared with baseline (440 ± 144 μm) in the Lucentis group.

CONCLUSION

The dexamethasone implant affected the aqueous cytokines and proteins MCP-1, sICAM-1, sVCAM-1 and MIG, whereas ranibizumab treatments reduced VEGF and PIGF levels. Morphological changes may diverge from cytokine changes. Results may indicate a rationale for a combination therapy for CSME using both agents, the dexamethasone implant and repeatedly administered ranibizumab injections.

Serum pro-inflammatory factors as predictors of persistent diabetic macular oedema with limited anatomic response to anti-VEGF: association with intravitreal injection treatment profiles in real-world setting

PURPOSE

To study the role of serum levels of pro-inflammatory factors in the identification of persistent diabetic macular oedema (DME) cases with limited anatomic response to anti-VEGF. Additionally, possible predictive associations between serum factors and intravitreal treatment profiles were analysed.

METHODS

Cases with DME were treated with monthly bevacizumab (BVZ). After the sixth month of follow-up, if the change in central foveal thickness (CFT) was <20% of baseline, combination treatment with triamcinolone was initiated. All cases underwent a baseline laboratory workup including inflammatory, metabolic and prothrombotic factors. The following outcome parameters were evaluated: percentage of CFT change from baseline, occurrence of persistent DME with <20% change in CFT, achieving CFT <330 μm with ≤6 BVZ injections, total number of intravitreal injections (IVI), number of IVI after the 6th month and number of triamcinolone acetonide (TCA) injections.

RESULTS

A total of 58 cases were included receiving a mean of 7.23 ± 1.55 IVI in 12 months, resulting in a significant improvement of visual acuity (VA) and CFT. No significant differences were found for baseline CFT, baseline LogMAR VA, diabetic retinopathy grade, age or duration of DM2 between cases initiating TCA and those treated only with anti-VEGF. Significant correlations were found between total number of IVI and the following serum factors: high-sensitivity C-reactive protein (hsCRP) (p = 0.004, r = 0.395), creatinine (p = 0.023, r = 0.338) and homocysteine (p = 0.037, r = 0.309). Regression analysis revealed that hsCRP was a significant predictor of TCA treatment (p = 0.028, r²  = 0.350). Cases requiring ≤6 IVI had significantly lower values of hsCRP (1.33 ± 1.07 versus 2.46 ± 2.18 mg/l, p = 0.016) and creatinine (0.71 ± 0.28 versus 0.94 ± 0.19 mg/dl, p = 0.003).

CONCLUSIONS

Serum markers of microvascular damage (hsCRP, homocysteine and creatinine) were associated with a higher frequency of IVI due to persistent DME, suggesting a role for such biomarkers in the identification of limited responders to anti-VEGF monotherapy.

Anti-VEGF Therapy Reduces Inflammation in Diabetic Macular Edema

PURPOSE

Correlations among the aqueous flare value (an indicator of inflammation), several functional-morphologic parameters, and aqueous humor levels of multiple cytokines or inflammatory factors were investigated in patients with diabetic macular edema (DME) receiving intravitreal rani-bizumab injection (IRI).

METHODS

Aqueous humor levels of 12 cytokines, growth factors, or inflammatory factors were measured in 46 DME patients who received IRI. Vascular endothelial growth factor (VEGF), soluble VEGF receptor (sVEGFR), and the other cytokines/inflammatory factors were measured by the suspension array method. In addition, aqueous flare values were measured with a laser flare meter, and central macular thickness (CMT) was examined by optical coherence tomography.

RESULTS

At 1 month after IRI therapy, the aqueous flare value showed a significant decrease compared with before treatment (baseline). Significant correlations were noted between the aqueous flare value and the aqueous humor levels of 6 factors/cytokines, including sVEGFR-1, placental growth factor, monocyte chemoattractant protein 1, soluble intercellular adhesion molecule-1, interleukin (IL)-6, and interferon-inducible 10-kDa protein (IP-10). There was also a significant correlation between the change in aqueous flare value and improvement in CMT 1 month after IRI.

CONCLUSIONS

These findings suggest that IRI reduces subclinical inflammation and that the aqueous flare value is influenced by inflammatory factors/cytokines. In addition, the change in the aqueous flare value may be an indicator of the response of CMT to IRI in patients with DME.

Claudin-5 Redistribution Induced by Inflammation Leads to Anti-VEGF-Resistant Diabetic Macular Edema

Approximately 40% of patients with diabetic macular edema (DME) are resistant to anti-vascular endothelial growth factor (VEGF) therapy (rDME). Here, we demonstrate that significant correlations between inflammatory cytokines and VEGF, as observed in naive DME, are lost in patients with rDME. VEGF overexpression in the mouse retina caused delayed inflammatory cytokine upregulation, monocyte/macrophage infiltration (CD11b⁺ Ly6C⁺ CCR2⁺ cells), macrophage/microglia activation (CD11b⁺ CD80⁺ cells), and blood-retinal barrier disruption due to claudin-5 redistribution, which did not recover with VEGF blockade alone. Phosphorylated protein analysis of VEGF-overexpressed retinas revealed rho-associated coiled-coil-containing protein kinase (ROCK) activation. Administration of ripasudil, a selective ROCK inhibitor, attenuated retinal inflammation and claudin-5 redistribution. Ripasudil also contributed to the stability of claudin-5 expression by both transcriptional enhancement and degradation suppression in inflammatory cytokine-stimulated endothelium. Notably, the anti-VEGF agent and the ROCK inhibitor were synergic in suppressing cytokine upregulation, monocyte/macrophage infiltration, macrophage/microglia activation, and claudin-5 redistribution. Furthermore, in vitro analysis confirmed that claudin-5 redistribution depends on ROCK2 but not on ROCK1. This synergistic effect was also confirmed in human rDME cases. Our results suggest that ROCK-mediated claudin-5 redistribution by inflammation is a key mechanism in the anti-VEGF resistance of DME.

A 12-month prospective study to evaluate the efficacy of using the treat-and-extend regimen with intravitreal aflibercept as a Second-Line Treatment for Diabetic Macular Oedema (the TADI Study)

PURPOSE

To evaluate the efficacy of intravitreal aflibercept as a second-line therapy in eyes with persistent diabetic macular oedema (DMO) despite receiving initial bevacizumab treatment.

METHODS

A prospective multicentre study was conducted in nine academic clinics in Israel. Starting from the first follow-up visit, a treat-and-extend regimen was applied in which the treatment intervals were extended by 2 weeks based on macular thickness using SD-OCT. The primary outcome was central subfield thickness (CST) at week 52.

RESULTS

Forty-four patients (n = 48 eyes) were recruited to the study, and 43 eyes completed 52 weeks of follow-up. Patients received a mean (±SD) of 7.9 ± 3.5 bevacizumab injections before enrolment. The mean (±SD) CST under aflibercept therapy decreased from 468 ± 131 μm at baseline to 303 ± 67 μm at 52 weeks (p = 0.002), and best corrected visual acuity improved from 64 ± 15 ETDRS letters at baseline to 75 ± 8 letters at week 52 (p = 0.001). Twenty (46%) eyes met the treat-and-extend criteria and received a mean (±SD) of 10.9 ± 2 aflibercept injections.

CONCLUSIONS

Eyes with persistent DMO following initial bevacizumab therapy had a marked reduction in macular thickness and improved visual acuity following 1 year of treatment with intravitreal aflibercept. Less than half of the patients met eligibility criteria for extension of the treatment interval; for these patients, the treat-and-extend regimen resulted in a maximum treatment interval of 10 weeks during the first year.

Management of diabetic macular edema: experts' consensus in Taiwan

Diabetic macular edema (DME) is the most common cause of vision loss among patients with diabetes mellitus (DM), rendering it an important growing challenge in ophthalmology. In the past decades, the management strategies for DME had a few paradigm shifts, and the advent of an expanding number of anti-vascular endothelial growth factor (VEGF) agents also calls for an in-depth examination of the currently available evidence. This article was composed with the intention to provide recommendations for practicing clinicians to improve the management and, through it the outcomes of DME. Drawing from current guideline recommendations, clinical trial findings and local clinical experiences, these consensus recommendations for the management of DME were formed by an expert panel through iterations of discussion and voting. First, the treatment goal of DME is to achieve best visual outcome with edema improvement while minimizing treatment burden. Second, anti-VEGF therapy should be considered as the first-line treatment for patients with center-involving DME causing vision loss. Baseline visual acuity (VA) and central subfield thickness (CST) should be taken into consideration when choosing anti-VEGF agents. Third, early intensive anti-VEGF therapy (at least 3 monthly doses) is important for better patients' VA and anatomical improvement. In non-responders who have already been treated with 3-5 injections of anti-VEGF agents, it is reasonable to switch to other modalities, such as steroids. Finally, for the follow-up phase, fixed or individualized dosing should be considered based on VA and OCT.

Glucocorticoid-transactivated TSC22D3 attenuates hypoxia- and diabetes-induced Müller glial galectin-1 expression via HIF-1α destabilization

Galectin‐1/LGALS1, a newly recognized angiogenic factor, contributes to the pathogenesis of diabetic retinopathy (DR). Recently, we demonstrated that glucocorticoids suppressed an interleukin‐1β‐driven inflammatory pathway for galectin‐1 expression in vitro and in vivo. Here, we show glucocorticoid‐mediated inhibitory mechanism against hypoxia‐inducible factor (HIF)‐1α‐involved galectin‐1 expression in human Müller glial cells and the retina of diabetic mice. Hypoxia‐induced increases in galectin‐1/LGALS1 expression and promoter activity were attenuated by dexamethasone and triamcinolone acetonide in vitro. Glucocorticoid application to hypoxia‐stimulated cells decreased HIF‐1α protein, but not mRNA, together with its DNA‐binding activity, while transactivating TSC22 domain family member (TSC22D)3 mRNA and protein expression. Co‐immunoprecipitation revealed that glucocorticoid‐transactivated TSC22D3 interacted with HIF‐1α, leading to degradation of hypoxia‐stabilized HIF‐1α via the ubiquitin‐proteasome pathway. Silencing TSC22D3 reversed glucocorticoid‐mediated ubiquitination of HIF‐1α and subsequent down‐regulation of HIF‐1α and galectin‐1/LGALS1 levels. Glucocorticoid treatment to mice significantly alleviated diabetes‐induced retinal HIF‐1α and galectin‐1/Lgals1 levels, while increasing TSC22D3 expression. Fibrovascular tissues from patients with proliferative DR demonstrated co‐localization of galectin‐1 and HIF‐1α in glial cells partially positive for TSC22D3. These results indicate that glucocorticoid‐transactivated TSC22D3 attenuates hypoxia‐ and diabetes‐induced retinal glial galectin‐1/LGALS1 expression via HIF‐1α destabilization, highlighting therapeutic implications for DR in the era of anti‐vascular endothelial growth factor treatment.

The Evolving Treatment of Diabetic Retinopathy

Purpose

To review the current therapeutic options for the management of diabetic retinopathy (DR) and diabetic macular edema (DME) and examine the evidence for integration of laser and pharmacotherapy.

Methods

A review of the PubMed database was performed using the search terms diabetic retinopathy, diabetic macular edema, neovascularization, laser photocoagulation, intravitreal injection, vascular endothelial growth factor (VEGF), vitrectomy, pars plana vitreous surgery, antiangiogenic therapy. With additional cross-referencing, this yielded 835 publications of which 301 were selected based on content and relevance.

Results

Many recent studies have evaluated the pharmacological, laser and surgical therapeutic strategies for the treatment and prevention of DR and DME. Several newer diagnostic systems such as optical coherence tomography (OCT), microperimetry, and multifocal electroretinography (mfERG) are also assisting in further refinements in the staging and classification of DR and DME. Pharmacological therapies for both DR and DME include both systemic and ocular agents. Systemic agents that promote intensive glycemic control, control of dyslipidemia and antagonists of the renin-angiotensin system demonstrate beneficial effects for both DR and DME. Ocular therapies include anti-VEGF agents, corticosteroids and nonsteroidal anti-inflammatory drugs. Laser therapy, both as panretinal and focal or grid applications continue to be employed in management of DR and DME. Refinements in laser devices have yielded more tissue-sparing (subthreshold) modes in which many of the benefits of conventional continuous wave (CW) lasers can be obtained without the adverse side effects. Recent attempts to lessen the burden of anti-VEGF injections by integrating laser therapy have met with mixed results. Increasingly, vitreoretinal surgical techniques are employed for less advanced stages of DR and DME. The development and use of smaller gauge instrumentation and advanced anesthesia agents have been associated with a trend toward earlier surgical intervention for diabetic retinopathy. Several novel drug delivery strategies are currently being examined with the goal of decreasing the therapeutic burden of monthly intravitreal injections. These fall into one of the five categories: non-biodegradable polymeric drug delivery systems, biodegradable polymeric drug delivery systems, nanoparticle-based drug delivery systems, ocular injection devices and with sustained release refillable devices. At present, there remains no one single strategy for the management of the particular stages of DR and DME as there are many options that have not been rigorously tested through large, randomized, controlled clinical trials.

Conclusion

Pharmacotherapy, both ocular and systemic, will be the primary mode of intervention in the management of DR and DME in many cases when cost and treatment burden are less constrained. Conventional laser therapy has become a secondary intervention in these instances, but remains a first-line option when cost and treatment burden are more constrained. Results with subthreshold laser appear promising but will require more rigorous study to establish its role as adjunctive therapy. Evidence to support an optimal integration of the various treatment options is lacking. Central to the widespread adoption of any therapeutic regimen for DR and DME is substantiation of safety, efficacy, and cost-effectiveness by a body of sound clinical trials.

DEXAMETHASONE IMPLANT FOR DIABETIC MACULAR EDEMA IN NAIVE COMPARED WITH REFRACTORY EYES: The International Retina Group Real-Life 24-Month Multicenter Study. The IRGREL-DEX Study

PURPOSE

To investigate efficacy and safety of repeated dexamethasone (DEX) implants over 24 months, in diabetic macular edema (DME) eyes that were treatment naive compared with eyes refractory to anti-vascular endothelial growth factor treatment, in a real-life environment.

METHODS

This multicenter international retrospective study assessed best-corrected visual acuity and central subfield thickness (CST) of naive and refractory eyes to anti-vascular endothelial growth factor injections treated with dexamethasone implants. Safety data (intraocular pressure rise and cataract surgery) were recorded.

RESULTS

A total of 130 eyes from 125 patients were included. Baseline best-corrected visual acuity and CST were similar for naive (n = 71) and refractory eyes (n = 59). Both groups improved significantly in vision after 24 months (P < 0.001). However, naive eyes gained statistically significantly more vision than refractory eyes (+11.3 ± 10.0 vs. 7.3 ± 2.7 letters, P = 0.01) and were more likely to gain ≥10 letters (OR 3.31, 95% CI 1.19-9.24, P = 0.02). At 6, 12, and 24 months, CST was significantly decreased compared with baseline in both naive and refractory eyes; however, CST was higher in refractory eyes than in naive eyes (CST 279 ± 61 vs. 313 ± 125 μm, P = 0.10).

CONCLUSION

Over a follow-up of 24 months, vision improved in diabetic macular edema eyes after treatment with dexamethasone implants, both in eyes that were treatment naive and eyes refractory to anti-vascular endothelial growth factor treatment; however, improvement was greater in naive eyes.

Deep learning-based single-shot prediction of differential effects of anti-VEGF treatment in patients with diabetic macular edema

Anti-vascular endothelial growth factor (VEGF) agents are widely regarded as the first line of therapy for diabetic macular edema (DME) but are not universally effective. An automatic method that can predict whether a patient is likely to respond to anti-VEGF therapy can avoid unnecessary trial and error treatment strategies and promote the selection of more effective first-line therapies. The objective of this study is to automatically predict the efficacy of anti-VEGF treatment of DME in individual patients based on optical coherence tomography (OCT) images. We performed a retrospective study of 127 subjects treated for DME with three consecutive injections of anti-VEGF agents. Patients' retinas were imaged using spectral-domain OCT (SD-OCT) before and after anti-VEGF therapy, and the total retinal thicknesses before and after treatment were extracted from OCT B-scans. A novel deep convolutional neural network was designed and evaluated using pre-treatment OCT scans as input and differential retinal thickness as output, with 5-fold cross-validation. The group of patients responsive to anti-VEGF treatment was defined as those with at least a 10% reduction in retinal thickness following treatment. The predictive performance of the system was evaluated by calculating the precision, sensitivity, specificity, and area under the receiver operating characteristic curve (AUC). The algorithm achieved an average AUC of 0.866 in discriminating responsive from non-responsive patients, with an average precision, sensitivity, and specificity of 85.5%, 80.1%, and 85.0%, respectively. Classification precision was significantly higher when differentiating between very responsive and very unresponsive patients. The proposed automatic algorithm accurately predicts the response to anti-VEGF treatment in DME patients based on OCT images. This pilot study is a critical step toward using non-invasive imaging and automated analysis to select the most effective therapy for a patient's specific disease condition.

Current concepts of pharmacotherapy of diabetic macular edema

Introduction: Diabetic macular edema (DME) is a sight threatening disease and a major cause for blindness for people in working age. The pathogenesis is multifactorial and complex. The pharmacotherapy of DME addresses both the inhibition of vascular endothelial growth factor (VEGF) by the intravitreal injection of VEGF inhibitors and inflammatory processes by the intravitreal application of steroids. Several trials have been published reporting on the efficacy and safety of these treatments.Areas covered: This review discusses original research articles including basic science and clinical studies as well as review articles focusing on the role of inflammation and VEGF expression in DME. It discusses newly published clinical trials on intravitreal pharmacotherapy for DME. The literature was searched using Medline/PubMed and was selected given its relevance for the topic to be discussed.Expert opinion: Our knowledge regarding the pathophysiology of diabetic macular edema has significantly increased. Some of these insights have been successfully transferred into current treatment strategies already including VEGF suppression or anti-inflammatory treatments using steroids. The identification of additional pathophysiological aspects and their relevance as potential treatment targets will be a future challenge in the treatment of DME. A better knowledge on the complex pathophysiology will also help to establish combination strategies.

Bevacizumab versus triamcinolone for persistent diabetic macular edema: a randomized clinical trial

PURPOSE

To evaluate 24-week visual acuity and anatomic outcomes of two "pro re nata" (prn) treatment strategies (intravitreal bevacizumab [IVB] prn versus intravitreal triamcinolone acetonide [IVT] prn) in patients with persistent diabetic macular edema (pDME) after 24 weeks of prn-IVB.

METHODS

One hundred eyes with center-involving DME were enrolled and treated with prn-IVB for 24 weeks; at week 24, eyes with pDME (central subfield thickness [CST] on spectral domain optical coherence tomography > 300 μm) were randomized to IVB monthly prn (group I; prn-IVB) or IVT every 3 months prn (group II; prn-IVT) and eyes in which the CST was ≤ 300 μm were assigned to continue prn-IVB (group III).

RESULTS

Seventy-four eyes completed a 48-week study period. At week 24, 65 (79.3%) eyes still had DME with CST > 300 μm and, therefore, were randomized to prn-IVB (group I, n = 33) or prn-IVT (group II, n = 32); the remaining 17 (20.7%) eyes had CST ≤ 300 μm and were assigned to continued treatment with prn-IVB (group III). At baseline, mean CST (μm) ± standard error of the mean (SEM) was 447.2 ± 24.4, 478.0 ± 19.7, and 386.0 ± 21.0 in groups I, II, and III, respectively (p > 0.05). At week 48, there was no significant difference in mean CST between groups I and II (369.9 ± 23.3 and 426.0 ± 26.1, respectively; p = 0.9995). A significant reduction in mean CST, compared with baseline, was noted at weeks 28 (p = 0.0002) and 44 (p = 0.0002) in group II. Group I did not show a significant reduction in mean CST compared with baseline at any study visit. There were no significant differences in mean CST between groups I and II at any study visit. At baseline, mean ± SEM best-corrected visual acuity (BCVA) (logMAR) was 0.50 ± 0.00, 0.60 ± 0.10, and 0.50 ± 0.10 in groups I, II, and III, respectively (p > 0.05). At week 48, there was no statistically significant difference in mean BCVA between groups I and II (0.50 ± 0.10 and 0.80 ± 0.10, respectively; p = 0.4473). There was no significant improvement in mean BCVA, as compared with baseline, at any study follow-up visit in any of the groups. Group II demonstrated significantly lower BCVA after 24 weeks of IVT (at week 48) compared with baseline (p = 0.0435). There was no significant difference in mean BCVA between groups I and II at any time-point.

CONCLUSION

In eyes with pDME after 24 weeks of treatment with prn-IVB, there was no difference between continued treatment with prn-IVB versus a treatment switch to prn-IVT with respect to mean BCVA or mean CST at week 48. However, BCVA was stable in the prn-IVB group, while prn-IVT was associated with BCVA reduction from baseline and a higher risk of IOP elevation.

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.

Surgical Therapy for Macular Edema: What We Have Learned through the Decades

Macular edema is a leading cause of functional visual loss in retinal vascular or ocular inflammatory diseases. Because persistent macular edema can lead to irreversible retinal damage, multi-approached treatment should be considered to achieve complete resolution of macular edema. With an enhanced understanding of its pathophysiology, numerous therapeutic options have been developed for the management of macular edema over the decades. Although medical therapies account for the mainstay of treatment, surgical approaches with vitrectomy can play an important role in the management of macular edema, depending on its mechanism of fluid accumulation. The index review focuses on the efficacy of surgical therapy for macular edema secondary to various ocular diseases including diabetic retinopathy, uveitis, and retinal vein occlusion, and consequently provides the evidences that may expand the knowledge and support the employment of surgical options.

Aqueous Humor Cytokines and Long-Term Response to Anti-Vascular Endothelial Growth Factor Therapy in Diabetic Macular Edema

PURPOSE

To determine the association of aqueous humor cytokine concentrations with long-term treatment response to anti-vascular endothelial growth factor (VEGF) agents in diabetic macular edema (DME).

DESIGN

Retrospective case series.

METHODS

Pooled data of aqueous humor cytokine concentrations collected at baseline and 2-month follow-up (2 injections) for treatment-naïve eyes with center-involving DME previously enrolled in a prospective study were reviewed. Subjects receiving intravitreal anti-VEGF injections outside of study protocol as per standard of care were classified into Responders versus Nonresponders based on qualitative assessment of optical coherence tomography for persistence of DME at longitudinal follow-up visits.

RESULTS

Of the 41 eyes, 85% were classified as Responders with a significant decline in baseline central subfield thickness and macular volume (P values < .001), and 15% were identified as Nonresponders to anti-VEGF therapy over 51.4 ± 18.7 months of follow-up. No significant difference in baseline aqueous humor VEGF concentration was noted, while at the 2-month follow-up the Nonresponder group had a significantly higher VEGF concentration compared with the Responder group (451.5 ± 690.9 pg/mL vs 113.7 ± 211.4 pg/mL; P = .02). The Responder group also demonstrated a significant decline from baseline to 2-month follow-up in concentration of intercellular adhesion molecule-1 (P < .001), interleukin-10 (P = .041), monocyte chemotactic protein-1 (P = .046), placental growth factor (P = .027), and transforming growth factor-β2 (P = .017).

CONCLUSIONS

Aqueous humor cytokine concentrations serve as an early biomarker for long-term response to anti-VEGF therapy and may enable more effective treatment regimens that improve anatomical outcomes in eyes with DME.

The Diabetic Retinopathy Clinical Research Network (DRCR.net) and Its Contributions to the Treatment of Diabetic Retinopathy

Over the past two decades, the Diabetic Retinopathy Clinical Research Network (now known as the DRCR Retina Network) has contributed to multiple and substantial advances in the clinical care of diabetic eye disease. Network studies helped establish anti-vascular endothelial growth factor (VEGF) agents as an effective alternative to panretinal photocoagulation for eyes with proliferative diabetic retinopathy (PDR) and as first-line therapy for eyes with visual impairment for diabetic macular edema (DME), defined treatment algorithms for the use of intravitreal medications in these conditions, and provided critical data to understand how to better evaluate the diabetic eye using optical coherence tomography and other imaging modalities. Ongoing DRCR.net studies will address whether anti-VEGF therapy is effective at preventing vision-threatening complications in eyes with severe non-proliferative diabetic retinopathy, if photobiomodulation has a beneficial effect in eyes with DME, and whether initiation of DME treatment with bevacizumab and rescue with aflibercept can provide visual outcomes as good as those achieved with aflibercept alone. Future plans for the Network also include the expansion into non-diabetic eye disease in areas such as age-related macular degeneration.

Persistent Macular Thickening Following Intravitreous Aflibercept, Bevacizumab, or Ranibizumab for Central-Involved Diabetic Macular Edema With Vision Impairment: A Secondary Analysis of a Randomized Clinical Trial

Importance

Prevalence of persistent central-involved diabetic macular edema (DME) through 24 weeks of anti-vascular endothelial growth factor therapy and its longer-term outcomes may be relevant to treatment.

Objective

To assess outcomes of DME persisting at least 24 weeks after randomization to treatment with 2.0-mg aflibercept, 1.25-mg bevacizumab, or 0.3-mg ranibizumab.

Design, Setting, and Participants

Post hoc analyses of a clinical trial, the DRCR.net Protocol T among 546 of 660 participants (82.7%) meeting inclusion criteria for this investigation.

Interventions

Six monthly intravitreous anti-vascular endothelial growth factor injections (unless success after 3 to 5 injections); subsequent injections or focal/grid laser as needed per protocol to achieve stability.

Main Outcomes and Measures

Persistent DME through 24 weeks, probability of chronic persistent DME through 2 years, and at least 10-letter (≥ 2-line) gain or loss of visual acuity.

Results

The mean age of participants was 60 years, 363 (66.5%) were white, and 251 (46.0%) were women. Persistent DME through 24 weeks was more frequent with bevacizumab (118 of 180 [65.6%]) than aflibercept (60 of 190 [31.6%]) or ranibizumab (73 of 176 [41.5%]) (aflibercept vs bevacizumab, P < .001; ranibizumab vs bevacizumab, P < .001; and aflibercept vs ranibizumab, P = .05). Among eyes with persistent DME through 24 weeks (n = 251), rates of chronic persistent DME through 2 years were 44.2% with aflibercept, 68.2% with bevacizumab (aflibercept vs bevacizumab, P = .03), and 54.5% with ranibizumab (aflibercept vs ranibizumab, P = .41; bevacizumab vs ranibizumab, P = .16). Among eyes with persistent DME through 24 weeks, proportions with vs without chronic persistent DME through 2 years gaining at least 10 letters from baseline were 62% of 29 eyes vs 63% of 30 eyes (P = .88) with aflibercept, 51% of 70 vs 55% of 31 (P = .96) with bevacizumab, and 45% of 38 vs 66% of 29 (P = .10) with ranibizumab. Only 3 eyes with chronic persistent DME lost at least 10 letters.

Conclusions and Relevance

Persistent DME was more likely with bevacizumab than with aflibercept or ranibizumab. Among eyes with persistent DME, eyes assigned to bevacizumab were more likely to have chronic persistent DME than eyes assigned to aflibercept. These results suggest meaningful gains in vision with little risk of vision loss, regardless of anti-vascular endothelial growth factor agent given or persistence of DME through 2 years. Caution is warranted when considering switching therapies for persistent DME following 3 or more injections; improvements could be owing to continued treatment rather than switching therapies.

Trial Registration

clinicaltrials.gov Identifier: NCT01627249.

Emerging Insights and Interventions for Diabetic Retinopathy

PURPOSE OF REVIEW

To introduce recent advances in the understanding of diabetic retinopathy and to summarize current and emerging strategies to treat this common and complex cause of vision loss.

RECENT FINDINGS

Advances in retinal imaging and functional analysis indicate that retinal vascular and neural pathologies exist long before the development of clinically visible retinopathy. Such diagnostics could facilitate risk stratification and selective early intervention in high-risk patients. Antagonists of the vascular endothelial growth factor pathway effectively reduce vision loss in diabetes and promote regression of disease severity. Promising new strategies to treat diabetic retinopathy involve novel systemic diabetes therapy and ocular therapies that antagonize angiogenic growth factor signaling, improve blood-retina barrier function and neurovascular coupling, modulate neuroretinal metabolism, or provide neuroprotection. Long considered a pure microvasculopathy, diabetic retinopathy in fact affects the neural and vascular retina as well as neurovascular communication. Emerging therapies include those that target neuroretinal dysfunction in addition to those modulating vascular biology.

Treatment of Diabetic Macular Edema

PURPOSE OF REVIEW

Diabetes mellitus is a global epidemic which is growing in prevalence, and diabetic macular edema (DME) is a leading cause of visual impairment among patients affected by this disease. Our objective is to review current and upcoming therapeutic approaches to DME.

RECENT FINDINGS

Once considered the gold standard in treatment of DME, focal/grid laser is now reserved mostly for non-center-involving DME, while anti-vascular endothelial growth factor (anti-VEGF) therapy has become the first-line treatment. However, suboptimal responders to anti-VEGF and the burden of frequent injections have stimulated the development of novel approaches. Corticosteroids can be effective in treating DME, but adverse effects such as intraocular pressure elevation and cataract formation must be considered. Emerging therapeutics and drug delivery systems in the pipeline offer exciting potential solutions to this vision-threatening disease. Multiple types of therapeutics targeting various pathways implicated in the pathogenesis of DME may help lessen the global burden of vision loss from diabetes.

Relationship between duration and extent of oedema and visual acuity outcome with ranibizumab in diabetic macular oedema: A post hoc analysis of Protocol I data

BACKGROUND/OBJECTIVES

This post hoc analysis explores the relationship between residual oedema exposure after ranibizumab treatment initiation and long-term visual acuity outcome in eyes with centre-involved diabetic macular oedema (DMO).

SUBJECTS/METHODS

Eyes randomised to the ranibizumab + prompt or deferred laser treatment arms in the Protocol I trial and with observed central retinal thickness (CRT) readings at baseline and ≥1 follow-up visits (n = 367) were stratified by 1) oedema duration (number of study visits with CRT ≥ 250 µm during the first 52 weeks of ranibizumab treatment); and 2) oedema extent (amount of excess CRT [≥ 250 µm] at each study visit, averaged over the first 52 weeks). Associations between measures of residual oedema and best-corrected visual acuity (BCVA) were assessed in multiple regression analyses.

RESULTS

Oedema duration and oedema extent during the first 52 weeks of ranibizumab treatment showed significant negative associations with BCVA improvement at weeks 52, 104 and 156. Eyes with the most persistent oedema gained (mean) 4.4 (95% CI 0.1─8.7) fewer Early Treatment Diabetic Retinopathy Study (ETDRS) letters at week 156 than eyes with the least persistent oedema (P = 0.044). Eyes with the greatest amount of oedema gained (mean) 9.3 (95% CI 4.0─14.5) fewer ETDRS letters at week 156 than eyes with the least amount of oedema (P < 0.001).

CONCLUSIONS

Macular oedema exposure over the first 52 weeks of ranibizumab treatment is a negative prognostic factor for long-term visual acuity improvement in centre-involved DMO.

Dexamethasone for unresponsive diabetic macular oedema: optical coherence tomography biomarkers

PURPOSE

To analyse the effects of intravitreal dexamethasone implant (DEX) in patients with diabetic macular oedema (DME) unresponsive to ranibizumab treatment, in relation to the inflammatory optical coherence tomography (OCT) retinal features, subfoveal neuroretinal detachment (SND) and hyperreflective retinal spots (HRS).

METHODS

Patients with DME poorly responsive to three injections of ranibizumab were treated with DEX. Best-corrected visual acuity (BCVA) and central macula thickness (CMT, measured by Spectralis SD-OCT) were assessed at baseline and at 1, 3, and 6 months.

RESULTS

Overall, 44 eyes were included in the study. In the whole group, mean BCVA (baseline 51.5 ± 8.3 letters) increased significantly at 1 month (to 56.9 ± 8.8 letters; Tukey HSD p = 0.017) and was 55.5 ± 8.8 letters at 3 months (Tukey HSD p = 0.128). Central macula thickness (CMT) reduced significantly at 1 and 3 months (417 ± 149 μm and 469 ± 128 μm, respectively, both Tukey HSD p < 0.001 versus baseline). Subgroup analysis showed a significant BCVA increase at 1 month in eyes with SND + HRS (from 51.2 ± 9.2 to 58.2 ± 9.0, p = 0.029), and a trend to BCVA increase in eyes with HRS (from 52.3 ± 6.4 to 56.8 ± 7.9, p = 0.080), with a significant CMT decrease in both groups (p < 0.001). No changes of either parameter were found in eyes without SND and HRS.

CONCLUSION

Spectral domain OCT is useful in identifying some inflammatory features in DME. Among DME eyes 'poorly responsive' to ranibizumab, those with SND and HRS responded better to DEX implants than those without these features.

Long-term outcomes after intravitreal dexamethasone treatment in steroid responders

AIMS

Intravitreal steroid implants have emerged as an adjunctive therapy in diabetic macular edema (DME) in patients refractory to anti-vascular endothelial growth factor agents. However, the use of these agents in patients with a prior history of steroid-induced ocular hypertension is limited. The present study aimed to analyze long-term intraocular pressure (IOP) response to the dexamethasone implant in patients with DME and a history of steroid-induced increase in IOP.

METHODS

In a multicenter retrospective review, 17 eyes with DME and a history of steroid-induced increase in IOP to > 21 mmHg were treated with the dexamethasone implant and followed for 18 months. Patients with a history of vitrectomy of vitreoretinal interface pathology were excluded. The primary outcomes were the change in IOP and use of IOP-lowering agents.

RESULTS

Among the study population (17 eyes), there was no significant change in mean IOP from baseline through 18 months (15.9 ± 2.0-14.6 ± 2.8 mmHg; p = 0.18). The number of patients requiring IOP-lowering agents rose from 5 at baseline to 14 at 18 months (p = 0.0049). None of the study eyes required surgical treatment.

CONCLUSIONS

Though dexamethasone does predictably lead to an increase in IOP, this adverse effect was effectively managed with topical treatment. The present study suggests that the intravitreal dexamethasone implant may be considered in patients with DME and a history of steroid-induced ocular hypertension who have exhausted first-line treatments.

Early versus late switch: How long should we extend the anti-vascular endothelial growth factor therapy in unresponsive diabetic macular edema patients?

PURPOSE

To compare the results of early versus late switch to the dexamethasone intravitreal implant Ozurdex^® in patients with diabetic macular edema who had a poor response to vascular endothelial growth factor inhibitors.

METHODS

Retrospective and single-center study conducted, in a real setting, on consecutive diabetic macular edema patients who were switch to an intravitreal dexamethasone implant after a poor response to anti-vascular endothelial growth factor treatment. Study sample was divided into two groups: (1) early-switch group, included those eyes who received three anti-vascular endothelial growth factor injections before switch and (2) late-switch group, included those eyes that received six or more anti-vascular endothelial growth factor injections before switch. The primary end-point was the difference in mean change in best-corrected visual acuity and in central subfoveal thickness.

RESULTS

A total of 69 (31 early-switch group and 38 late-switch group) eyes were included. In the early-switch group, median (25-75 quartile range) best-corrected visual acuity significantly increase from 0.2 (0.2-0.5) at baseline to 0.4 (0.3 -0.7) at month 24 (p = 0.0043). Whereas, in the late-switch group, best-corrected visual acuity did not increase (p = 0.8602). Central subfoveal thickness was significantly reduced in both early- and late-switch groups, p = 0.0002 and 0.0038, respectively. The proportion of eyes obtaining a central subfoveal thickness reduction ⩾ 10% was significantly greater in the early-switch group than in the late-switch group (71.0% vs 47.4%, respectively, p = 0.0498). Three (9.7%) and 10 (26.3%) eyes have developed ocular hypertension during the study in the early- and late-switch groups, respectively, p = 0.0816.

CONCLUSION

Early switch to Ozurdex in patients who did not adequately respond to anti-vascular endothelial growth factor therapy provided better functional and anatomical outcomes.

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.

Current and Future Pharmacologic Therapies for Diabetic Retinopathy

Background:

Currently, diabetic retinopathy is the leading cause of permanent visual loss in workingage adults in industrialized nations. The chronic microangiopathic changes associated with diabetic retinopathy lead to the most common causes of severe permanent visual loss: diabetic macular edema (DME) and proliferative diabetic retinopathy (PDR). Multiple studies have evaluated different pharmacotherapies for different levels of retinopathy.

Methods:

A review of the pathophysiology of diabetic retinopathy and current and emerging pharmacotherapies for diabetic retinopathy.

Results:

Historically, DME has been the primary focus of treatment in patients with nonproliferative diabetic retinopathy (NPDR). Due to the rapidly increasing number of agents and treatment options, management algorithms for DME have become increasingly complex. Furthermore, spectral domain optical coherence tomography (OCT) has allowed unparalleled sensitivity and specificity for detecting macular edema. All available intravitreal vascular endothelial growth factor (VEGF) inhibitors have demonstrated efficacy in the treatment of patients with DME and PDR. Intravitreal triamcinolone acetonide has also proven beneficial in diabetic retinopathy. Most recently, various corticosteroids have been designed as sustained-release intraocular implants in order to reduce the burden and risks associated with retreatment. Current research is focused on providing new agents that target alternate pathways and signaling molecules to provide patients with additional therapeutic tools, especially in patients who have an incomplete response to the current medications.

Conclusion:

Anti-VEGF therapy has revolutionized the medical management of diabetic retinopathy. The most important existing challenges in the treatment of diabetic retinopathy are improving visual outcomes and decreasing the treatment burden associated with repeated intravitreal injections. Combination therapy with anti-VEGF and corticosteroids with other previously available treatments, such as panretinal photocoagulation, may be a reasonable clinical strategy to reduce the intravitreal injections burden. Many exciting novel drugs that target newly discovered pathways hold clinical promise. The results of ongoing randomized clinical trials will answer the important concerns surrounding new drugs and delivery devices: safety and visual outcomes.

Three-dimensional analysis of morphologic changes and visual outcomes in diabetic macular edema

PURPOSE

To investigate the association of retinal fluid volume with the visual and anatomic outcomes of patients with diabetic macular edema (DME) after treatment with bevacizumab.

STUDY DESIGN

Retrospective observational study.

METHODS

We retrospectively analyzed 65 eyes of 58 DME patients treated with bevacizumab. The volumes of the inner intraretinal fluid (IRF) in the inner nuclear layer (INL), outer IRF in the outer plexiform layer (OPL)/outer nuclear layer (ONL), and subretinal fluid (SRF) were calculated. The correlations between the baseline fluid volumes and best-corrected visual acuity (BCVA), area of disorganization of the retinal inner layers (DRIL), disrupted external limiting membrane (ELM), and disrupted ellipsoid zone (EZ) at 12 months after treatment were assessed.

RESULTS

The baseline volume of the inner IRF correlated with poor BCVA at the final visit (r = 0.52, P < .001) whereas the baseline volume of the outer IRF and SRF volume did not show a significant correlation with BCVA at the final visit (P = .07 and P = .61, respectively). The improvement in BCVA correlated with the reduction in the baseline volume of the inner IRF and outer IRF (r = 0.25, P = .04 and r = 0.36, P = .003), but not with the SRF volume (P = .59). The baseline volume of the inner IRF correlated positively with the area of DRIL and the disrupted ELM at the final visit (r = 0.56, P < .001 and r = 0.25, P = .04, respectively). Such relationship remained in each quadrant of the macula (P < .005 for all quadrants).

CONCLUSION

The baseline volume of the inner IRF correlated with a poor visual outcome, an increased DRIL area, and a more disrupted ELM area in patients with DME after treatment with bevacizumab.

Diabetic macular edema: Evidence-based management

Diabetic macular edema (DME) is the most common cause of vision loss in patients with diabetic retinopathy with an increasing prevalence tied to the global epidemic in type 2 diabetes mellitus. Its pathophysiology starts with decreased retinal oxygen tension that manifests as retinal capillary hyperpermeability and increased intravascular pressure mediated by vascular endothelial growth factor (VEGF) upregulation and retinal vascular autoregulation, respectively. Spectral domain optical coherence tomography (SD-OCT) is the cornerstone of clinical assessment of DME. The foundation of treatment is metabolic control of hyperglycemia and blood pressure. Specific ophthalmic treatments include intravitreal anti-VEGF drug injections, intravitreal corticosteroid injections, focal laser photocoagulation, and vitrectomy, but a substantial fraction of eyes respond incompletely to all of these modalities resulting in visual loss and disordered retinal structure and vasculature visible on SD-OCT and OCT angiography. Efforts to close the gap between the results of interventions within randomized clinical trials and in real-world contexts, and to reduce the cost of care increasingly occupy innovation in the social organization of ophthalmic care of DME. Pharmacologic research is exploring other biochemical pathways involved in retinal vascular homeostasis that may provide new points of intervention effective in those cases unresponsive to current treatments.

Ozurdex for refractory macular edema secondary to diabetes, vein occlusion, uveitis and pseudophakia

OBJECTIVE

To analyze the functional and morphological effects of the intravitreal dexamethasone implant (Ozurdex, Allergan) on patients with macular edema secondary to retinal vein occlusion (RVO), diabetic retinopathy (DME), posterior noninfectious uveitis (NIU), or pseudophakic Irvine-Gass syndrome (IGS).

METHODS

144 charts were retrospectively reviewed; 100 eyes met inclusion criteria for analysis: at least one intravitreal dexamethasone implant injection, refractory to antivascular endothelial growth factor, and had ≥6 months of follow-up postinsertion. The primary outcome was the efficacy of the dexamethasone implant in reducing macular edema as measured by reduction in central retinal thickness (CRT). Secondary outcomes included visual acuity (VA), duration of treatment efficacy (measured by time to next treatment), and safety. The Wilcoxon signed-rank test was used to compare values from baseline, and Kaplan-Meier survival curves were used to analyze time to retreatment.

RESULTS

There were 28 patients with RVO, 30 with DME, 24 with posterior NIU, and 18 with IGS. VA improved from baseline to month 6 in all groups, but was not statistically significant. CRT improved in all 4 groups, and was statistically significant for DME (p = 0.008) and NIU (p = 0.05). At 3 months, 34 patients (41.5%) required retreatment; by month 6, 46 patients (56.1%) required retreatment. There was a large variation between the groups in number of patients requiring intraocular pressure (IOP)-lowering medications. Two patients needed IOP-lowering surgery. One patient developed endophthalmitis.

CONCLUSION

The use of intravitreal dexamethasone implants in patients with refractory retinal diseases is well tolerated and results in consistently improved anatomic outcomes, but the positive anatomic outcomes are not necessarily correlated to improvements in visual function. Patients who are treated earlier in the disease process will had better outcomes. This patient population were refractory to treatment and, therefore, have less-predictable functional outcomes.

Cost-effectiveness of fluocinolone acetonide implant (ILUVIEN®) in UK patients with chronic diabetic macular oedema considered insufficiently responsive to available therapies

BACKGROUND

Diabetic macular oedema (DMO) may lead to visual loss and blindness. Several pharmacological treatments are available on the National Health Service (NHS) to United Kingdom patients affected by this condition, including intravitreal vascular endothelial growth factor inhibitors (anti-VEGFs) and two types of intravitreal steroid implants, releasing dexamethasone or fluocinolone acetonide (FAc). This study aimed to assess the value for money (cost-effectiveness) of the FAc 0.2 μg/day implant (ILUVIEN®) in patients with chronic DMO considered insufficiently responsive to other therapies.

METHODS

We developed a Markov model with a 15-year time horizon to estimate the impact of changes in best-corrected visual acuity in DMO patients on costs and quality-adjusted life years. The model considered both eyes, designated as the "study eye", defined at model entry as phakic with an ongoing cataract formation or pseudophakic, and the "fellow eye". The model compared the FAc 0.2 μg/day implant with a 700 μg dexamethasone implant (pseudophakic patients only) or with usual care, defined as a mixture of laser photocoagulation and anti-VEGFs (phakic and pseudophakic patients). Costs were estimated from the perspective of the NHS and Personal Social Services; full NHS prices were used for drugs.

RESULTS

In patients who were pseudophakic at baseline, at 36 months, the FAc implant provided an additional gain of 4.01 and 3.64 Early Treatment Diabetic Retinopathy Study (ETDRS) letters compared with usual care and the dexamethasone implant, respectively. Over the 15-year time horizon, this translated into 0.185 additional quality-adjusted life years (QALYs) at an extra cost of £3066 compared with usual care, and 0.126 additional QALYs at an extra cost of £1777 compared with dexamethasone. Thus, incremental cost-effectiveness ratios (ICERs) were £16,609 and £14,070 per QALY gained vs. usual care and dexamethasone, respectively. In patients who were phakic at baseline, the FAc 0.2 μg/day implant provided an additional gain of 2.96 ETDRS letters at 36 months compared with usual care, which, over 15 years, corresponded to 0.11 additional QALYs at an extra cost of £3170, resulting in an ICER of £28,751 per QALY gained.

CONCLUSION

The FAc 0.2 μg/day implant provided good value for money compared with other established treatments, especially in pseudophakic patients.

Dexamethasone implant as an adjuvant therapy to ranibizumab loading dose in persistent diabetic macular edema

PURPOSE

This study evaluates the effectiveness of a single-dose dexamethasone implant (DI) as an auxiliary therapy to continued intravitreal ranibizumab (IVR) treatment in patients with persistent diabetic macular edema (DME).

METHODS

Twenty-five pseudophakic eyes of 25 patients with DME who underwent a single injection of DI as an adjuvant therapy following an IVR loading dose were examined retrospectively. All patients were treatment naive and had a poor response to a loading dose of three consecutive monthly IVR injections. IVR treatments were continued pro re nata after the DI. The main outcome measures were changes in best-corrected visual acuity (BCVA) and central macular thickness (CMT) at 1, 3, 6 and 8 months post-DI treatment.

RESULTS

After the IVR loading dose, the mean BCVA and CMT were 0.9 ± 0.6 LogMAR and 478.2 ± 107.8 µm, respectively. One month after the DI, the mean BCVA and CMT had improved to 0.6 ± 0.4 LogMAR (p = 0.005) and 313.8 ± 62.7 µm (p < 0.001), respectively. This improvement was maintained with mean 0.8 ± 0.8 IVR injections throughout the follow-up period. The final mean BCVA and CMT were 0.5 ± 0.5 LogMAR and 298.4 ± 71.5 µm. Subgroup analyses revealed that different DME types did not have any effect on CMT or BCVA improvement (p = 0.188, p = 0.136; respectively).

CONCLUSION

Adding DI results in rapid anatomical and visual improvement in patients who respond poorly to an IVR loading dose. Improvements may be maintained with additional IVR in follow-up.

Early Response to Anti-Vascular Endothelial Growth Factor and Two-Year Outcomes Among Eyes With Diabetic Macular Edema in Protocol T

PURPOSE

Assess associations of 2-year visual acuity (VA) outcomes with VA and optical coherence tomography central subfield thickness (CST) after 12 weeks of anti-vascular endothelial growth factor treatment for diabetic macular edema in DRCR.net Protocol T.

DESIGN

Randomized clinical trial.

METHODS

Setting: Multicenter (89 U.S. sites).

PATIENT POPULATION

Eyes with VA and CST data from baseline and 12-week visits (616 of 660 eyes randomized [93.3%]).

INTERVENTION

Six monthly injections of 2.0 mg aflibercept, 1.25 mg bevacizumab, or 0.3 mg ranibizumab; subsequent injections and focal/grid laser as needed for stability.

MAIN OUTCOME MEASURES

Change in VA from baseline and VA letter score at 2 years.

RESULTS

Twelve-week VA response was associated with 2-year change in VA and 2-year VA letter score for each drug (P < .001) but with substantial individual variability (multivariable R² = 0.38, 0.29, and 0.26 for 2-year change with aflibercept, bevacizumab, and ranibizumab, respectively). Among eyes with less than 5-letter gain at 12 weeks, the percentages of eyes gaining 10 or more letters from baseline at 2 years were 42% (20 of 48), 31% (21 of 68), and 47% (28 of 59), and median 2-year VA was 20/32, 20/32, and 20/25, in the aflibercept, bevacizumab, and ranibizumab groups, respectively. Twelve-week CST response was not strongly associated with 2-year outcomes.

CONCLUSIONS

A suboptimal response at 12 weeks did not preclude meaningful vision improvement (ie, ≥ 10-letter gain) in many eyes at 2 years. Eyes with less than 5-letter gain at 12 weeks often had good VA at 2 years without switching therapies.

Anti-Vascular Endothelial Growth Factor Treatment for Diabetic Macular Edema in a Real-World Clinical Setting

PURPOSE

To report the long-term outcomes of intravitreal anti-vascular endothelial growth factor (VEGF) treatment for diabetic macular edema (DME) in a real-world clinical setting and to assess the efficacy of subsequent alternative treatments in eyes with suboptimal response to anti-VEGF.

DESIGN

Retrospective interventional case series.

METHODS

The medical records of consecutive eyes with center-involving DME, treated between August 2008 and June 2015 with 3 monthly intravitreal anti-VEGF injections-with or without prompt or deferred laser-followed by pro re nata re-treatment, were reviewed. A subgroup of eyes that were unresponsive to the treatment received subsequent alternative therapeutic options, including switching to another anti-VEGF drug, intravitreal injection of dexamethasone, and vitrectomy.

RESULTS

A total of 170 eyes of 129 patients were included in the study. The mean follow-up (FU) was 45.6 months (SD 18; minimum 12-maximum 81). The change in mean best-corrected visual acuity (BCVA) at 1-year FU was +5 ETDRS letters (P < .0001). Improvement in BCVA was statistically significant up to 5 years. Improvement in central macular thickness (CMT) was statistically significant up to the last FU visit. In eyes with suboptimal response, no significant visual improvement was found by switching to another anti-VEGF (P =.4347). Twenty-four eyes treated with intravitreal dexamethasone and 14 with vitrectomy exhibited a significant reduction in CMT with variable functional responses. In these eyes, better BCVA gain was found in cases with an early change of the treatment strategy.

CONCLUSION

The results support treatment with intravitreal anti-VEGF for DME in real-world clinical settings and suggest that an early change of the therapeutic strategy should be considered for eyes unresponsive to the treatment.

Shall we stay, or shall we switch? Continued anti-VEGF therapy versus early switch to dexamethasone implant in refractory diabetic macular edema

AIMS

To compare functional and anatomical outcomes of continued anti-vascular endothelial growth factor (VEGF) therapy versus dexamethasone (DEX) implant in eyes with refractory diabetic macular edema (DME) after three initial anti-VEGF injections in a real-world setting.

METHODS

To be included in this retrospective multicenter, case-control study, eyes were required: (1) to present with early refractory DME, as defined by visual acuity (VA) gain ≤ 5 letters or reduction in central subfield thickness (CST) ≤ 20%, after a loading phase of anti-VEGF therapy (three monthly injections) and (2) to treat further with (a) anti-VEGF therapy or (b) DEX implant. Main outcome measures were change in visual acuity (VA) and central subfield thickness (CST) at 12 months. Due to imbalanced baseline characteristics, a matched anti-VEGF group was formed by only keeping eyes with similar baseline characteristics as those in the DEX group.

RESULTS

A total of 110 eyes from 105 patients were included (anti-VEGF group: 72 eyes, DEX group: 38 eyes). Mean change in VA at 12 months was - 0.4 ± 10.8 letters (anti-VEGF group), and + 6.1 ± 10.6 letters (DEX group) (P = 0.004). Over the same period, mean change in CST was + 18.3 ± 145.9 µm (anti-VEGF group) and - 92.8 ± 173.6 µm (DEX group) (P < 0.001). Eyes in the DEX group were more likely to gain ≥ 10 letters (OR 3.71, 95% CI 1.19-11.61, P = 0.024) at month 12.

CONCLUSIONS

In a real-world setting, eyes with DME considered refractory to anti-VEGF therapy after three monthly injections which were switched to DEX implant and had better visual and anatomical outcomes at 12 months than those that continued treatment with anti-VEGF therapy.

Evaluation of the effect of combined intravitreal ranibizumab injection and sub-tenon steroid injection in the treatment of resistant diabetic macular edema

PURPOSE

To compare sub-tenon steroid plus anti-VEGF injection with anti-VEGF injection solely in the treatment of resistant diabetic macular edema (DME).

METHOD

Patients who exhibited insufficient anatomic [over 350 μm central macular thickness (CMT)] and less than 3 lines of visual gain at least six anti-VEGF injections, were randomly divided into two groups. In group I, the anti-VEGF injection was performed 10 days after the sub-tenon steroid injection [Triamcinolone acetonide (Sinakort-A^®)]. And anti-VEGF was performed when needed during the follow-up period. In group II, treatment was continued with anti-VEGF only. All patients' visual acuity and CMT were followed up for 6 months.

RESULTS

The baseline BCVA in group I and group II was 0.51 ± 0.667 logMAR and 0.47 ± 0.60 logMAR, respectively (p = 0.52). In group I and II, at the end of 6-month follow-up, BCVA improved to 0.38 ± 0.60 logMAR (p < 0.001) and 0.43 ± 0.60 logMAR (p = 0.20), respectively. The baseline CMT in group I and group II was 494 ± 118.32 and 438.20 ± 90.99 μm, respectively (p = 0.029). In group I and II, at the end of 6 months, CMT decreased to 302.57 ± 69.89 μm (p < 0.001) and 439.20 ± 107.6 μm (p = 0.96), respectively.

CONCLUSION

Adding steroid to routine anti-VEGF treatment is an effective way of treatment method for resistant DME.