Intravitreal ranibizumab and dexamethasone implant injections as primary treatment of diabetic macular edema: simultaneously double protocol

Efficacy and safety of dexamethasone or triamcinolone in combination with anti-vascular endothelial growth factor therapy for diabetic macular edema: A systematic review and meta-analysis with trial sequential analysis

BACKGROUND

The clinical efficacy of anti-vascular endothelial growth factors (anti-VEGFs), corticosteroids, and their combined treatment for diabetic macular edema (DME) has been substantiated by numerous studies. However, it remains uncertain whether the therapeutic benefits of the combined treatment with corticosteroids and anti-VEGFs is superior to those of anti-VEGF monotherapy. Consequently, we conducted a meta-analysis to compare the efficacy and safety of combined treatment with dexamethasone or triamcinolone and anti-VEGF versus anti-VEGF monotherapy in DME treatment.

METHODS

An exhaustive search of the literature was performed on February 23, 2024, scanning through the databases including PubMed, Web of Science, Embase, and the Cochrane Library, with the aim of identifying all relevant studies. The combined results for efficacy and safety were analyzed using the standard mean difference (SMD) and relative risk (RR), both of which were presented with 95% confidence interval (CI). The assessment of heterogeneity was conducted via Cochran's Q test, I2 statistics, and the implementation of a 95% prediction interval (PI). All analyses were performed by R 4.3.1, Stata 12.0, and TSA v0.9.5.10 Beta software.

RESULTS

This meta-analysis incorporated 21 eligible studies. The overall analysis revealed that combined treatment of dexamethasone or triamcinolone with anti-VEGF agents did not demonstrate superiority over anti-VEGF monotherapy in improving best-corrected visual acuity (BCVA) (Dexamethasone: SMD -0.266, 95% CI -1.001 to 0.468, 95% PI -2.878 to 2.346; Triamcinolone: SMD -0.340, 95% CI -1.230 to 0.550, 95% PI -3.554 to 2.874) and reducing central macular thickness (CMT) (Dexamethasone: SMD -1.255, 95% CI -2.861 to 0.350; Triamcinolone: SMD -0.207, 95% CI -0.895 to 0.481, 95% PI -2.629 to 2.215). However, the combination therapy significantly increased the risk of elevated intraocular pressure (RR 5.783, 95% CI 3.007 to 11.121, 95% PI 0.520 to 56.931) and ocular hypertension (RR 8.885, 95% CI 2.756 to 28.649, 95% PI 1.262 to 39.208). Subgroup analysis suggests that dexamethasone plus anti-VEGF therapy showed a greater reduction in central subfield thickness (SMD -0.440, 95% CI -0.755 to -0.126) compared to anti-VEGF monotherapy among patients with persistent DME.

CONCLUSION

Our study confirmed that dexamethasone or triamcinolone plus anti-VEGF therapy did not show superior efficacy in improving BCVA and reducing CMT in DME patients compared with anti-VEGF monotherapy. Clinicians should weigh the pros and cons comprehensively when implementing combined therapy.

Anti-VEGF Monotherapy vs Anti-VEGF and Steroid Combination Therapy for Diabetic Macular Edema: A Meta-analysis

Introduction: To compare the safety and efficacy of antivascular endothelial growth factor (anti-VEGF) monotherapy vs anti-VEGF and steroid combination therapy in treatment-naïve and treatment-resistant patients with diabetic macular edema (DME). Methods: A systematic literature search was conducted from January 2005 to December 2022. Sixteen randomized control trials (RCTs) published in English that reported the efficacy or safety of monotherapy and combination therapy in patients with DME were included. Results: The 16 RCTs included 1166 eyes. Monotherapy was associated with a significantly better best-corrected visual acuity (BCVA) at the final follow-up (weighted mean difference [WMD], -0.04 logMAR; 95% CI, -0.07 to -0.02; P = .002; I 2 = 0%). No significant differences were observed in the change in BCVA between groups at the final observation. Monotherapy was associated with a significantly smaller change in retinal thickness at the final follow-up (WMD, 37.63 μm; 95% CI, 11.67-63.60; P = .005; I 2 = 78%) and with a significantly lower risk for intraocular pressure-related adverse events (AEs) (risk ratio, 0.27; 95% CI, 0.15-0.46; P ≤ .001; I 2 = 0%). The risk for cataract-related AEs was not significantly different between groups (P = .06). The results in treatment-naïve patients were similar. In treatment-resistant patients, the change in retinal thickness at the final follow-up was similar between groups (P = .14) but the risk for cataract-related AEs was significantly lower in the monotherapy group in 2 RCTs (risk ratio, 0.09; 95% CI, 0.01-0.66; P = .02; I 2 = 0%). Conclusions: The changes in BCVA were similar despite combination therapy being associated with greater changes in retinal thickness. However, increased complications were seen with combination therapy. Most results in treatment-naïve patients and treatment-resistant patients were similar.

The natural compound sinometumine E derived from Corydalis decumbens promotes angiogenesis by regulating HIF-1/ VEGF pathway in vivo and in vitro

The rhizome of Corydalis decumbens is a traditional Chinese medicine commonly utilized in the clinical treatment of acute ischemic stroke. Numerous phytochemical and biological investigations have demonstrated that protoberberine alkaloids from C. decumbens exhibit diverse pharmaceutical activities against various diseases. Sinometumine E (SE), a protoberberine alkaloid isolated from C. decumbens for the first time, is characterized by a complex 6/6/6/6/6/6 hexacyclic skeleton. In the current study, we investigated the protective effects of SE on endothelial cell injury and its angiogenesis effects in zebrafish. The results suggested that SE showed significant anti-ischemic effects on OGD/R-induced HBEC-5i and HUVECs cell ischemia/reperfusion injury model. Furthermore, it promoted angiogenesis in PTK787-induced, MPTP-induced, and atorvastatin-induced vessel injury models of zebrafish, while also suppressing hypoxia-induced locomotor impairment in zebrafish. Transcriptome sequencing analysis provided a sign that SE likely to promotes angiogenesis through the HIF-1/VEGF signaling pathway to exert anti-ischemic effects. Consistently, SE modulated several genes related to HIF-1/VEGF signal pathway, such as hif-1, vegf, vegfr-2, pi3k, erk, akt and plcγ. Molecular docking analysis revealed that VEGFR-2 exhibited high binding affinity with SE, and western blot analysis confirmed that SE treatment enhanced the expression of VEGFR-2. In conclusion, our study profiled the angiogenic activities of SE in vitro and in vivo. The key targets and related pathways involved in anti-ischemic effects of SE, shedding light on the pharmacodynamic components and mechanisms of Corydalis decumbens, and provides valuable insights for identifying effective substances for the treatment of ischemic stroke.

Intraretinal Hyper-Reflective Foci Are Almost Universally Present and Co-Localize With Intraretinal Fluid in Diabetic Macular Edema

Purpose

In diabetic macular edema (DME), hyper-reflective foci (HRF) has been linked to disease severity and progression. Using an automated approach, we aimed to investigate the baseline distribution of HRF in DME and their co-localization with cystoid intraretinal fluid (IRF).

Methods

Baseline spectral-domain optical coherence tomography (SD-OCT) volume scans (N = 1527) from phase III clinical trials YOSEMITE (NCT03622580) and RHINE (NCT03622593) were segmented using a deep-learning-based algorithm (developed using B-scans from BOULEVARD NCT02699450) to detect HRF. The HRF count and volume were assessed. HRF distributions were analyzed in relation to best-corrected visual acuity (BCVA), central subfield thickness (CST), and IRF volume in quartiles, and Diabetic Retinopathy Severity Scores (DRSS) in groups. Co-localization of HRF with IRF was calculated in the central 3-mm diameter using the en face projection.

Results

HRF were present in most patients (up to 99.7%). Median (interquartile range [IQR]) HRF volume within the 3-mm diameter Early Treatment Diabetic Retinopathy Study ring was 1964.3 (3325.2) pL, and median count was 64.0 (IQR = 96.0). Median HRF volumes were greater with decreasing BCVA (nominal P = 0.0109), and increasing CST (nominal P < 0.0001), IRF (nominal P < 0.0001), and DRSS up to very severe nonproliferative diabetic retinopathy (nominal P < 0.0001). HRF co-localized with IRF in the en face projection.

Conclusions

Using automated HRF segmentation of full SD-OCT volumes, we observed that HRF are a ubiquitous feature in DME and exhibit relationships with BCVA, CST, IRF, and DRSS, supporting a potential link to disease severity. The spatial distribution of HRF closely followed that of IRF.

A combination of suprachoroidal injection of triamcinolone using a custom-made needle and intravitreal Ziv-aflibercept every eight weeks to manage naïve/denovo central DME: a single-center retrospective case series

BACKGROUND

Previous studies have shown promising effects of combining intravitreal bevacizumab and suprachoroidal injection of triamcinolone acetonide in treating DME. However, further research is needed.

OBJECTIVE

To assess the efficacy and safety of combining both intravitreal Ziv-aflibercept and suprachoroidal injection of triamcinolone acetonide using a custom-made needle in naïve and de novo central diabetic macular edema (DME) patients every eight weeks for 24 weeks.

METHODS

Central macular thickness was measured via spectral domain-optical coherence tomography, and best-corrected visual acuity was measured via a Snellen chart at baseline and at 4, 8, 12, 16, and 24 weeks postinjection. Additionally, cataract progression, intraocular pressure (IOP), and ocular safety were analyzed.

RESULTS

A total of 10 eyes of 6 patients were treated with suprachoroidal injections of triamcinolone acteonid combined with an intravitreal injection of Ziv-aflibercept. Vision improved from 0.69 log minimum angle of resolution (MAR) at baseline to 0.39 log MAR after treatment. Central macular thickness significantly decreased from 462.3 ± 166 μm at baseline to 362.7 ± 77.6 μm at 24 weeks postinjection.

CONCLUSION

Suprachoroidal injection of triamcinolone using a custom-made needle with the intravitreal agent Ziv-aflibercept to treat de novo/naïve central DME has favorable outcomes and adequate safety results. Moreover, this study demonstrated the benefit of adapting the previous treatment combination for extending the interval between anti-VEGF treatments from 4 to 8 weeks, which could prevent further expenses, especially in low-income countries.However, large multicenter randomized clinical trials with longer follow-up periods are needed to assess this treatment route, especially in low-income and resourced countries.

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

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

Anti-VEGF combined with ocular corticosteroids therapy versus anti-VEGF monotherapy for diabetic macular edema focusing on drugs injection times and confounding factors of pseudophakic eyes: A systematic review and meta-analysis

PURPOSE

To assess the effectiveness and safety of combining intravitreal endothelial growth factor inhibitor (anti-VEGF) and ocular corticosteroids for diabetic macular edema (DME).

METHODS

Articles concentrating on the efficacy and safety of combining anti-VEGF and ocular corticosteroids therapy for DME versus anti-VEGF monotherapy was screened systematically. Meta-analysis was conducted on the basis of a protocol registered in the PROSPERO (CRD42023408338) and performed on the extracted continuous variables and dichotomous variables. The outcome was expressed as weighted mean difference (MD) and risk ratio (RR).

RESULTS

Add up to 21 studies including 1468 eyes were enrolled in this study. The MD for best-corrected visual acuity (BCVA) improvement at 1/3/6/12-month between the combination therapy group and monotherapy group were 2.56 (95% CI [0.43, 4.70]), 2.46 (95% CI [-0.40, 5.32]), - 1.76 (95% CI [-3.18, -0.34]), - 1.94 (95% CI [-3.87, 0.00]), respectively. The MD for central retinal thickness (CMT) reduction at 1/3/6/12-month between two groups were - 66.27 (95% CI [-101.08, -31.47]), - 33.62 (95% CI [-57.55, -9.70]), - 4.54 (95% CI [-16.84, 7.76]), - 26.67 (95% CI [-41.52, -11.82]), respectively. Additionally, the combination group had higher relative risk of high intraocular pressure and cataract progression events.

CONCLUSIONS

Anti-VEGF combined with ocular corticosteroids had a significant advantage over anti-VEGF monotherapy within 3 months of DME treatment, which reached the maximum with increasing anti-VEGF injection times to 3. However, with the prolongation of the treatment cycle, the effect of combined therapy after 6 months was no better than monotherapy, and the side effects of combined therapy were more severe.

Efficacy and safety profile of intravitreal dexamethasone implant versus antivascular endothelial growth factor treatment in diabetic macular edema: a systematic review and meta-analysis

To better understand the efficacy of intravitreal dexamethasone implant (Ozurdex) versus antivascular endothelial growth factor (anti-VEGF) treatment in patients with diabetic macular edema (DME). A systematic review and meta-analysis. The study included randomized control trials (RCTs) and non-randomized control trials (Non-RCTs) before December 2021 that compare the efficacy of Ozurdex-related therapyand anti-VEGF therapy. We searched PubMed, Cochrane Library, and EMBASE. The quality of the included studies was assessed carefully. 30 studies were included. Regarding BCVA change, the overall result revealed no significant differences between Ozurdex and anti-VEGF therapies in patients with nonresistant DME, but Ozurdex group had significantly more VA improvement than anti-VEGF therapies in patients with resistant DME (MD 0.12, 95% CI 0.02-0.21). In terms of central retinal thickness (CRT) decrease, there was a significant difference between Ozurdex therapy and anti-VEGF therapy in patients with nonresistant DME (MD 48.10, 95% CI 19.06-77.13) and resistant DME (MD 65.37, 95% CI 3.62-127.13). Overall, Ozurdex therapy resulted in significantly greater VA improvement and CRT decrease than anti-VEGF therapy in resistant DME patients. Ozurdex therapy was not inferior to anti-VEGF therapy in patients with nonresistant DME.

Intravitreal Ranibizumab and Dexamethasone Implant Injections as Primary Treatment of Diabetic Macular Edema: The Month 24 Results from Simultaneously Double Protocol

PURPOSE

To compare efficacy of simultaneously administered intravitreal dexamethasone implant (DEX implant) and ranibizumab (simultaneous double protocol) injections with ranibizumab monotherapy for diabetic macular edema (DME) at month 24.

METHODS

This is a prospective, consecutive, clinical interventional study. Naïve eyes with DME were randomized into two groups: 34 eyes received simultaneous double-protocol therapy and 34 eyes received ranibizumab monotherapy. The primary efficacy endpoint was change in visual acuity in month 24. The secondary efficacy endpoints were to evaluate gain of ≥15 letters, morphological changes and central foveal thickness. Decreased vision from DME (study eye BCVA, 20/40 or worse Snellen equivalent using ETDRS testing), the presence of DME with ≥300 μm foveal intraretinal cystoid spaces (within 1000 μm of the centre of the fovea), subfoveal neuroretinal detachment (SND), intraretinal hyperreflective foci (HRF, within 500 μm of the centre of the fovea) or foveal lipid exudates and external limiting membrane (ELM) and ellipsoid zone (EZ) disruption (within 500 μm of the centre of the fovea) on SD-OCT were eligible to enrol.

RESULTS

The mean baseline BCVA was 48 ± 23 letters in double protocol group and 52 ± 14 letters ranibizumab monotherapy group (p = 0.416). The mean number of ETDRS letters changed from baseline at 12 months versus change from baseline at month 24 in double protocol group and ranibizumab monotherapy group were +21.6 versus +20.2 and +9.6 versus +9.1, respectively. At the month 24 time point, 65.4% of patients in double protocol group and 26.2% of patients in ranibizumab monotherapy group had gained ≥15 ETDRS letters in BCVA from baseline (p < 0.001). The external limiting membrane (ELM) and ellipsoid zone (EZ) integrity were better in the double protocol group in comparison to ranibizumab monotherapy group at month 24. In addition, there was no statistically significant increase in the proportion of patients with epiretinal membrane in double protocol group at month 24, by the contrast with ranibizumab monotherapy group (p = 0.06 and p = 0.04 in the double protocol and ranibizumab monotherapy groups, respectively). From baseline to month 24, the mean central foveal thickness (CFT) was 672 ± 293 μm reduced to 278 ± 84 μm in double protocol group and was 631 ± 279 μm reduced to 356 ± 108 μm in ranibizumab monotherapy group (p < 0.001 and p < 0.001). From baseline to month 24, 38% (13/34) of eyes in double protocol group and 18% (6/34) of eyes in ranibizumab monotherapy group had at least 5 mmHg of IOP elevation (p = 0.012). Two grades or more increased cataract density were detected 27% (6/22) of eyes in the double protocol group and in 12.5% (3/24) of eyes in the ranibizumab monotherapy group from baseline to month 24 (p = 0.032).

CONCLUSION

According to the improvements in visual acuity and morphological changes achieved at month 24, the simultaneous double protocol therapy can be an effective treatment option for DME with inflammatory biomarkers on OCT or/and decreased visual acuity.

Expert recommendations for the management of diabetic macular edema with intravitreal dexamethasone implant: A Turkish Delphi study

PURPOSE

To provide consensus on the clinical use of intravitreal dexamethasone (DEX) implant for the treatment of diabetic macular edema (DME) in Turkey.

METHODS

A panel of 22 retina experts prepared 77 statements of recommendation, and 80 retinal specialists practicing in Turkey were chosen to vote either in support or against each one. A Delphi-based method was used through which the ophthalmologists were able to view all of the results anonymously after two rounds and modify their subsequent answers. The survey was conducted via a mini website, and statements without consensus were resent to the specialists with the latest vote results a week later.

RESULTS

A total of 72 ophthalmologists answered the first and second round questions. After the first stage, consensus was achieved on 55 of the statements, leaving 22 without agreement. After the second stage, consensus was reached on 11 of the remaining statements. Strong consensus was achieved on statements regarding the etiopathogenesis of DME and the first-line indications and safety of the DEX implant procedure. The panel recommended the use of DEX implant for patients with an arterial thromboembolic event in the last three months and also agreed that pro re nata DEX implant treatment not only provides better outcomes for DME patients but also reduces the treatment burden for those who could not receive an adequate number of anti-vascular endothelial growth factor (VEGF) injections.

CONCLUSION

This study provides clinical consensus and recommendations about the use of DEX implant in the clinical practice of DME management in Turkey.

KESTREL and KITE: 52-Week Results From Two Phase III Pivotal Trials of Brolucizumab for Diabetic Macular Edema

PURPOSE

To compare the efficacy and safety of brolucizumab with aflibercept in patients with diabetic macular edema (DME).

DESIGN

Double-masked, 100-week, multicenter, active-controlled, randomized trials.

METHODS

Subjects were randomized 1:1:1 to brolucizumab 3 mg/6 mg or aflibercept 2 mg in KESTREL (n = 566) or 1:1 to brolucizumab 6 mg or aflibercept 2 mg in KITE (n = 360). Brolucizumab groups received 5 loading doses every 6 weeks (q6w) followed by 12-week (q12w) dosing, with optional adjustment to every 8 weeks (q8w) if disease activity was identified at predefined assessment visits; aflibercept groups received 5 doses every 4 weeks (q4w) followed by fixed q8w dosing. The primary endpoint was best-corrected visual acuity (BCVA) change from baseline at Week 52; secondary endpoints included the proportion of subjects maintained on q12w dosing, change in Diabetic Retinopathy Severity Scale score, and anatomical and safety outcomes.

RESULTS

At Week 52, brolucizumab 6 mg was noninferior (NI margin 4 letters) to aflibercept in mean change in BCVA from baseline (KESTREL: +9.2 letters vs +10.5 letters; KITE: +10.6 letters vs +9.4 letters; P < .001), more subjects achieved central subfield thickness (CSFT) <280 µm, and fewer had persisting subretinal and/or intraretinal fluid vs aflibercept, with more than half of brolucizumab 6 mg subjects maintained on q12w dosing after loading. In KITE, brolucizumab 6 mg showed superior improvements in change of CSFT from baseline over Week 40 to Week 52 vs aflibercept (P = .001). The incidence of ocular serious adverse events was 3.7% (brolucizumab 3 mg), 1.1% (brolucizumab 6 mg), and 2.1% (aflibercept) in KESTREL; and 2.2% (brolucizumab 6 mg) and 1.7% (aflibercept) in KITE.

CONCLUSION

Brolucizumab 6 mg showed robust visual gains and anatomical improvements with an overall favorable benefit/risk profile in patients with DME.

Monoclonal antibodies in diabetic retinopathy

INTRODUCTION

Diabetic retinopathy (DR), as one of the main complications of diabetes, is among the leading causes of blindness and visual impairment worldwide.

AREAS COVERED

Current clinical therapies include photocoagulation, vitrectomy, and anti-vascular endothelial growth factor (VEGF) therapies. Bevacizumab and ranibizumab are two monoclonal antibodies (mAbs) inhibiting angiogenesis. Intravitreal ranibizumab and bevacizumab can decrease the rate of blindness and retinal thickness, and improve visual acuity whether as monotherapy or combined with other treatments. They can increase the efficacy of other treatments and decrease their adverse events. Although administered intravitreally, they also might enter the circulation and cause systemic effects. This study is aimed to review our current knowledge about mAbs, bevacizumab and ranibizumab, in DR including superiorities, challenges, and limitations. Meanwhile, we tried to shed light on new ideas to overcome these limitations. Our latest search was done in April 2021 mainly through PubMed and Google Scholar. Relevant clinical studies were imported.

EXPERT OPINION

Future direction includes detection of more therapeutic targets considering other components of DR pathophysiology and shared pathogenesis of DR and neurodegenerative diseases such as Parkinson's disease and Alzheimer's disease, the treat-and-extend regimen, and new ways of drug delivery and other routes of ocular drug administration.

Add-On Effect of Simultaneous Intravitreal Dexamethasone to Intravitreal Bevacizumab in Patients with Macular Edema Secondary to Branch Retinal Vein Occlusion

Purpose: To report the effect of simultaneous dexamethasone and bevacizumab combination treatment in patients with macular edema secondary to branch retinal vein occlusion (BRVO). Methods: Treatment-naive patients who had a macular edema secondary to BRVO with a duration of less than 1 month were treated either with intravitreal bevacizumab (Group-1) or intravitreal bevacizumab simultaneously combined with dexamethasone intravitreal implant (Group-2). In both groups, patients received monthly bevacizumab injection during the first 3 months. Between months 3 and 12, all patients were allowed to receive pro-re-nata bevacizumab. In Group-2, the first dexamethasone implant injection was simultaneously received with first bevacizumab injections. The patients were evaluated for re-treatment after 6 months and 11 months for second and third dexamethasone simultaneously with intravitreal bevacizumab. Results: In Group-1, 35 eyes of 35 patients and in Group-2, 32 eyes of 32 patients were treated. The mean gains in BCVA were +10.7 letters in the Group-1 and +21.3 letters in the Group-2 (P = 0.021) at month 12. The mean reduction in Central Macular Thickness (CMT) from the baseline were -173.74 μm in the Group-1 and -257.97 μm in the Group-2 (P = 0.0018). In Group-1, the mean intravitreal bevacizumab injection number was 7.18 ± 1.05. In Group-2, the mean intravitreal bevacizumab and dexamethasone injection number was 5.15 ± 1.24. There was a significant difference in mean injection numbers between 2 groups (P = 0.044). Conclusion: In the early period of macular edema adding dexamethasone to bevacizumab therapy does improve visual acuity and CMT, and reduce the injection frequency more than bevacizumab alone.

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

Purpose

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

Patients and Methods

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

Results

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

Conclusion

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

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

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

The prognostic role of optical coherence tomography in diabetic macular edema patients undergoing early dexamethasone implant shift

PURPOSE

To determine the prognostic characteristics of optical coherence tomography (OCT) parameters by evaluating diabetic macular edema (DME) patients with early dexamethasone (DEX) shift after three doses of intravitreal ranibizumab (RNB) injection.

METHODS

Fifty-four eyes of 34 patients who had DEX implant after three doses of RNB were included in this retrospective study. Early DEX shift includes patients who received direct DEX implant replacement after three doses of RNB load. Baseline OCT values and factors affecting best corrected visual acuity (BCVA) and central macular thickness (CMT) response were analyzed with logistic regression analyses.

RESULTS

The presence of subretinal fluid and hyperreflective spot (HRS) >20 were found to be a negative predictive factor for anatomical response. (p = 0.009, p = 0.001, respectively) Low initial BCVA creates a positive effect on visual gain.( p = 0.041) Giant outer nuclear layer cysts, completely disrupted inner segment-outer segment and HRS > 20 have a negative effect on visual gain. (p = 0.025, p = 0.043, p = 0.023, respectively) According to the receiver operating characteristic analysis, the subretinal fluid volume threshold at which >20% reduction in CMT occurs was determined to be 0.85 mm³. (sensitivity 70%, specificity 84% area under the curve 0.817, p = 0.021).

CONCLUSION

The presence of high number of HRS and high subretinal fluid volume at the baseline negatively affect prognosis even in patient groups with early DEX shift.