Dexamethasone intravitreal implant in retinal vein occlusion: real-life data from a prospective, multicenter clinical trial

Intravitreal Injection of Conbercept Combined with Dexamethasone for Macular Edema Following Central Retinal Vein Occlusion

Background

To compare the efficacy of intravitreal injections of Conbercept combined with dexamethasone (DEX) for macular edema (ME) following central retinal vein occlusion (CRVO).

Methods

This was a prospective, single-masked, randomised, controlled clinical trial. Patients with ME following CRVO were randomised into groups to receive intravitreal injections of 0.5 mg Conbercept plus 0.2 mg DEX or 0.5 mg Conbercept alone on day 0 followed by repeat injections as indicated. The primary outcome measure was the change in best-corrected visual acuity (BCVA) from baseline to month 12. Secondary outcome measures included decrease in central retinal thickness (CRT), injection frequency and interval and percentage of patients who gained more than 15 ETDRS letters or achieved a CRT of < 250 μm at month 12.

Results

33 males (51%) and 32 females (49%) were initially recruited with an average age of 56.64 ± 13.88 years. Patients in the Conbercept and Conbercept + DEX groups gained an average of 14.55 ± 19.19 and 14.88 ± 17.68 ETDRS letters, respectively, at months 12 (t = 4.221, P = 0.000; and t = 4.834, P = 0.000) with no significant difference between the two groups (t = 0.071, P = 0.943). In the Conbercept group, the mean reduction in CRT from baseline to month 12 was 435.26 ± 293.37 μm (t = 8.261, P = 0.000) compared to 431.36 ± 294.55 (t = 8.413, P = 0.000) in the Conbercept + DEX group. There was no significant difference between the two groups (t = 0.053, P = 0.958). The Conbercept + DEX group received fewer intravitreal injections. No major complications occurred.

Conclusion

Conbercept, alone or with DEX, can improve BCVA and reduce CRT in ME following CRVO without serious adverse events. The treatment interval was longer in the Conbercept + DEX group.

Trial Registration

The study was registered with the Chinese Clinical Trial Registry at 5 July 2017. (http://www.chictr.org.cn, 05/07/2017 Registration Number: ChiCTR-INR-17011877).

Applications and Recent Developments of Hydrogels in Ophthalmology

Hydrogels are a type of functional polymer material with a three-dimensional network structure composed of physically or chemically cross-linked polymers. All hydrogels have two common features: first, their structure contains a large number of hydrophilic groups; therefore, they have a high water content and can swell in water. Second, they have good regulation, and the physical and chemical properties of their cross-linked network can be changed by environmental factors and deliberate modification methods. In recent years, the application of hydrogels in ophthalmology has gradually attracted attention. By selecting an appropriate composition and cross-linking mode, hydrogels can be used in different fields for various applications, such as gel eye drops, in situ gel preparation, intravitreal injection, and corneal contact lenses. This Review provides a detailed introduction to the classification of hydrogels and their applications in glaucoma, vitreous substitutes, fundus diseases, corneal contact lenses, corneal diseases, and cataract surgery.

Anterior segment complications after dexamethasone implantations:real world data

PURPOSE

We aim to contribute to the literature in terms of treatment safety with our real world data by examining the anterior segment complications and follow-up results of patients who underwent dexamethasone implants in our clinic.

METHODS

The records of patients treated with at least one intravitreal dexamethasone implant for various retinal diseases: diabetic macular edema (265 eyes), central retinal vein occlusion (45 eyes), retinal vein branch occlusion (91 eyes), postoperative cystoid macular edema (18 eyes), non-infectious uveitis (37 eyes) and other (14 eyes) between July 2013 and April 2020 were reviewed.

RESULTS

After 925 injections were applied to 470 eyes of a total of 383 patients, the eyes were controlled during a mean follow-up of 24 months. No complications were detected in 328 eyes. Intraocular pressure (IOP) above 25 mmHg was detected in 97 eyes (20.6%) that had no previous history of ocular hypertension. Of these 97 eyes, 71 (73.1%) eyes with increased IOP were treated with topical monotherapy, 26 (26.8%) eyes were treated with topical combined therapy and 1 (1.03%) patient had glaucoma surgery. Cataracts requiring surgical intervention developed in 55 (%21.73) of 253 phakic eyes. Three patients have anterior chamber dislocation of dexamethasone, 1 patient was hospitalized with sterile endophthalmitis on the 7th day after the injection, and pars plana vitrectomy was performed.

CONCLUSION

This study is the first long-term follow-up study in our country evaluating the safety of dexamethasone implant injections in various retinal diseases and presenting the first real world data. Cataract progression and increased IOP were found to be the most common side effects. We observed that the patient's diagnosis did not cause a statistically significant change in the observation of side effects. As a result of our findings, close follow-up of IOP after the injection of dexamethasone implants would be appropriate.

Injectable Anti-Inflammatory Supramolecular Nanofiber Hydrogel to Promote Anti-VEGF Therapy in Age-Related Macular Degeneration Treatment

Age-related macular degeneration (AMD) is a major cause of visual impairment and severe vision loss worldwide, while the currently available treatments are often unsatisfactory. Previous studies have demonstrated both inflammation and oxidative-stress-induced damage to the retinal pigment epithelium are involved in the pathogenesis of aberrant development of blood vessels in wet AMD (wet-AMD). Although antivascular endothelial growth factor (VEGF) therapy (e.g., Ranibizumab) can impair the growth of new blood vessels, side effects are still found with repeated monthly intravitreal injections. Here, an injectable antibody-loaded supramolecular nanofiber hydrogel is fabricated by simply mixing betamethasone phosphate (BetP), a clinic anti-inflammatory drug, anti-VEGF, the gold-standard anti-VEGF drug for AMD treatment, with CaCl₂ . Upon intravitreal injection, such BetP-based hydrogel (BetP-Gel), while enabling long-term sustained release of anti-VEGF to inhibit vascular proliferation in the retina and attenuate choroidal neovascularization, can also scavenge reactive oxygen species to reduce local inflammation. Remarkably, such BetP-Gel can dramatically prolong the effective treatment time of conventional anti-VEGF therapy. Notably, anti-VEGF-loaded supramolecular hydrogel based on all clinically approved agents may be readily translated into clinical use for AMD treatment, with the potential to replace the current anti-VEGF therapy.

Results of intravitreal dexamethasone implant (Ozurdex®) for retinal vascular diseases with macular edema: An observational study of real-life situations

To evaluate the efficacy of intravitreal dexamethasone implants (Ozurdex®) for the treatment of macular edema (ME) associated with retinal vascular diseases in real-life situations. This retrospective study included patients with ME associated with retinal vascular occlusion (RVO) or diabetic macular edema (DME) treated with dexamethasone implants. Demographic data, best-corrected visual acuity (BCVA), and central retinal thickness (CRT) at baseline and at 1, 3, and 6 months postoperatively were collected and analyzed, and the adverse events were recorded. Forty-four eyes, 42 patients were included in the study. The mean logMAR BCVA improved from 0.79 ± 0.38 at baseline to 0.60 ± 0.34 (P < 0.001), 0.72 ± 0.38 (P = .002), and 0.72 ± 0.37 (P = .002) at 1, 3, and 6 months, respectively. The CRT decreased from 526.70 ± 159.58 µm at baseline to 279 ± 66.23, 422.91 ± 206.99, and 350.23 ± 151.51 µm at 1, 3, and 6 months, respectively (P < 0.001, all visits). The average number of injections was 1.43 ± 0.5. Nineteen eyes (43.18%) received second injections at an interval of 4.20 ± 0.61 months. The mean logMAR BCVA was greater in RVO than in DME patients and in treatment-naïve eyes than in previously treated ones. The baseline CRT of the reinjection group was significantly higher than that of the single-injection group for both the RVO (P < 0.001) and DME groups (P = .002). Nine eyes (20.45%) with increasing intraocular pressure (IOP) were well controlled with medication, and cataract progression was observed in five eyes (21.73%) during follow-up. The dexamethasone implant was effective for the treatment of macular edema secondary to RVO and DME in terms of visual acuity and CRT improvement over 6 months. The visual acuity was greater in the RVO and treatment-naïve eyes. Reinjection may be associated with a high baseline CRT. The increase in the occurrence of IOP and cataract progression was similar to that reported in previous studies.

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

Purpose

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

Methods

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

Results

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

Conclusion

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

Dexamethasone Intravitreal Implant for the Treatment of Macular Edema Following Retinal Vein Occlusion: Post Hoc Analysis of Post-Marketing Surveillance Data in the Real-World Setting in Korea

Purpose

To supplement established efficacy and safety data, this analysis evaluated the real-world use of dexamethasone (DEX) intravitreal implant 700 µg for retinal vein occlusion (RVO)-related macular edema in an Asian population and baseline factors potentially associated with DEX implant efficacy.

Patients and Methods

A prospective, observational, post-marketing surveillance study was conducted at 38 sites in South Korea in patients consecutively presenting with macular edema following branch or central RVO (BRVO, CRVO), and administered a first DEX implant. Follow-up visits and subsequent DEX or other therapies conformed with local practice. Outcome measures included best-corrected visual acuity (BCVA), change in BCVA from baseline, responder rates, and adverse events. Associations between baseline characteristics and BCVA gains were evaluated. Month-1, -2, -4, and -6 visit analysis windows were established.

Results

In all, 700 patients (79.1% BRVO, 20.9% CRVO) received 1.12 DEX implants (mean) and were followed for 101.5 days (standard deviation, 51.7); 90% received a single implant. Among patients with analyzable data, mean BCVA improved from baseline with peak changes in Month 2 of −0.193 and −0.212 LogMAR, (P < 0.0001) and remained significant in the BRVO subgroup at the Month 4 and 6 windows (P < 0.0001 and P = 0.0039, respectively). Treatment-naïve patients experienced greater BCVA increases. The proportion of patients with stable/improved BCVA tended to decrease after Month 2 through Month 6 and the decline was greater in the CRVO subgroup. At the Month-2 window, ≥1-, 2- and 3-line increases were positively associated with younger age, worse baseline BCVA, and treatment naivety. The most common adverse event was increased intraocular pressure.

Conclusion

In the real-world clinical setting in South Korea, DEX implant improved visual acuity and had a favorable safety profile similar to that reported in randomized controlled trials and observational European and North American studies. These data further support the value of DEX implant as a treatment option for RVO.

ClinicalTrials.gov Identifier

NCT01976650. Date of registration: November 6, 2013.

Intravitreal Dexamethasone Implants for Refractory Macular Edema in Eyes with Noninfectious Uveitis

Macular edema (ME) is a common cause of visual loss among eyes with uveitis, and its management can be challenging. Steroids are an effective treatment for ME, and intravitreal dexamethasone (DEX) implants provide sustained steroid release. The purpose of this study is to evaluate intravitreal DEX implant on refractory ME in eyes with noninfectious uveitis. A retrospective study including 52 eyes of 37 patients with refractory uveitic ME was conducted from January 2011 through August 2017 at Linkou Chang Gung Memorial Hospital in Taiwan. Patients’ demographic characteristics were collected. In addition, clinical information, including corrected visual acuity (VA), intraocular pressure (IOP), and central retinal thickness (CRT) on optical coherence tomography, was recorded and analyzed. During the study period, affected eyes received a total of 110 intravitreal DEX implants (range, one to six in each eye). After the first DEX implant injection in all eyes, VA significantly improved at one and two months. CRT significantly decreased one month after a single DEX implant, and the effect lasted for six months and waned over time. Patients receiving multiple DEX implants still showed significant decreases in CRT one month after the first implant. Increases in IOP were noted one month after the DEX implant, but the IOP could be medically controlled. Intravitreal DEX implants can effectively treat refractory uveitic ME, improving both VA and CRT with an acceptable safety profile. Further studies are necessary to evaluate the effect of multiple implants and long-term outcomes.

Short-term effectiveness prognostic factors after dexamethasone intravitreal implant in macular edema due to retinal vein occlusion

INTRODUCTION

The aim of this study was to describe functional and anatomical changes (best-corrected visual acuity [BCVA], central macular thickness [CMT], and central macular volume [CMV]) in patients with macular edema (ME) secondary to retinal vein occlusion (RVO) treated with intravitreal dexamethasone implant (IDI) and identify its clinical predictors in a real-world setting.

METHODS

Data from 111 patients who underwent IDI to treat RVO-associated ME were retrospectively reviewed. Demographic, preoperative, and postoperative variables were assessed using a logistic regression analysis to determine predictors of visual and anatomical improvement.

RESULTS

Mean BCVA, CMT, and CMV improved from baseline after IDI (p < 0.001). The strongest predictors of different treatment outcomes were: a baseline BCVA ⩽60 ETDRS letters (OR = 50.600; p < 0.001) and first IDI injection (OR = 2.988; p < 0.001) for BCVA gain ⩾15 Early Treatment Diabetic Retinopathy Study (ETDRS) letters; a baseline BCVA ⩽60 ETDRS letters (OR = 7.893; p = 0.002) and non-chronic ME (OR = 3.875; p = 0.019) for BCVA ⩾80 ETDRS letters achievement; a baseline CMT ⩾400 µm (OR = 49.083; p < 0.001) and a baseline CMV ⩾12 mm³ (OR = 4.235; p < 0.001) for CMT reduction ⩾50%; and a baseline CMT ⩾400 µm (OR = 11.471; p < 0.001) and a baseline CMV ⩾12 mm³ (OR = 10.284; p < 0.001) for CMV reduction ⩾15%.

CONCLUSION

This study confirmed the effectiveness of IDI to treat ME secondary to RVO and identified new predictive factors for two visual (⩾15 ETDRS letters gain and BCVA ⩾80 ETDRS letters) and two anatomical outcomes (>50% CMT and >15% CMV reduction).

Anterior chamber changes assessment by Scheimpflug analysis after intravitreal dexamethasone implantation

PURPOSE

To evaluate structural changes in the anterior chamber and intraocular pressure (IOP) changes following intravitreal dexamethasone implantation.

METHODS

Forty-two eyes of 42 patients that received intravitreal dexamethasone implant for the management of macular edema secondary to diabetic retinopathy or branch retinal vein occlusion (BRVO) were included in the study. IOP was measured by Goldmann applanation tonometry. Anterior chamber depth (ACD) and iridocorneal angle (ICA) was measured by a Scheimflug camera (Sirius, CSO, Italy) the day before the injection of the dexamethasone implant and on postoperative day 1, first week, and first month.

RESULTS

Mean IOP was 15.14 ± 2.77 mmHg before the procedure and, 15.67 ± 3.70 mmHg, 15.86 ± 3.11 mmHg, 16.21 ± 2.75 mmHg on day 1, first week, and first month following intravitreal dexamethasone implantation, respectively. Mean ICA and ACD were significantly higher in pseudophakic eyes compared to phakic eyes. However, there was no statistically significant change in ICA before and after the procedure (on postoperative day 1, first week, and first month) among both phakic and pseudophakic patients (p = 0.783). Similarly, ACD remained unchanged after the procedure (on postoperative day 1, first week, and first month) compared to the initial measurement (p = 0.802).

CONCLUSION

This study confirmed that there was an increase in IOP. However, these changes were not accompanied with a change in ACD or ICA.

Comparison of the effects of aflibercept and dexamethasone in central retinal vein occlusion with serous retinal detachment

Clinical relevance: Previous studies have shown the efficacy of aflibercept and dexamethasone in central retinal vein occlusion. However, the efficacy of these two drugs in central retinal vein occlusion accompanied by serous macular detachment has not been investigated and compared. This results in a search for more precise data to evaluate the effects of two drugs in real-world studies.Background: The aim of this study is to compare the efficacy of intravitreal aflibercept and dexamethasone implantation injections in central retinal vein occlusion accompanied by serous retinal detachment.Methods: Sixty-eight eyes of 68 patients with treatment-naive macular oedema post-central retinal vein occlusion were enrolled in the retrospectively designed study. All of the patients had serous retinal detachment at baseline. The patients received three intravitreal aflibercept injections with an interval of four weeks and followed by pro re nata treatment protocol (intravitreal aflibercept group, n = 37) or a single dose dexamethasone implantation injection (dexamethasone implantation group, n = 31). Best-corrected visual acuity, central retinal thickness and the height of serous retinal detachment parameters were compared at baseline, and in the first, second, third and sixth months.Results: The groups were similar in terms of baseline characteristics (p > 0.05 for all). The visual gain was greater in the intravitreal aflibercept group (p = 0.013). While the intravitreal aflibercept group had a significant central retinal thickness decrease in the first and sixth months (p = 0.011 and p = 0.001, respectively), this superiority was not observed during the entire follow-up period (p = 0.212). There was no difference in serous retinal detachment resolution between the groups (p = 0.403). Two patients in the intravitreal aflibercept group (5.4%) and five patients in the dexamethasone implantation group (16.1%) had serous retinal detachment at the final visit (p = 0.158).Conclusion: Both intravitreal aflibercept and dexamethasone implantation injections seemed to be effective in the treatment of central retinal vein occlusion with serous retinal detachment. Intravitreal aflibercept treatment yielded better results in terms of visual gain and showed a faster anatomical response.

Real-life medium term follow-up data for intravitreal dexamethasone implant in retinal vein occlusion

Macular edema (ME) is the most frequent vision threatening consequence after retinal vein occlusion (RVO). In this study, we evaluate the effect of dexamethasone intravitreal implants (DII, Ozurdex) in a real-life cohort of 99 patients with ME due to RVO. All patients who received DII for ME following RVO between 2011 and 2016 at the University Eye Hospital Freiburg, Germany and who had fully accessible electronic medical records were eligible for this study. Most of the patients included in this study were not treatment-naïve: 61 eyes had received prior anti-VEGF drugs, 6 eyes had received intravitreal corticosteroids (triamcinolone) and 15 had been treated with both; 17 eyes were treatment-naïve. Mean follow-up was 312 ± 310 days. Mean visual acuity (VA) was maintained throughout the observation period (mean VA at baseline: 66.7 ± 23.5 letters; at last observation 64.9 ± 28.3). Central retinal thickness (CRT) decreased from 526 ± 179 µm at baseline to 431 ± 199 µm. Mean intraocular pressure (IOP) increased from 14.4 ± 3.1 mmHg at baseline to 17.1 ± 6.3 mmHg. Cataract surgery was performed in 22% of phakic eyes. DII was used as second-line treatment in the majority of cases in this cohort. The fact that mean VA remained unchanged while mean CRT decreased illustrates that morphologic improvement does not always translate into functional gain. Mean IOP was maintained within normal limits and cataract formation was as expected in this age group.

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

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

Feelings, preoperative anxiety, and need for information in patients undergoing intravitreal injections

PURPOSE

To assess feelings, preoperative anxiety, and need for information in patients undergoing intravitreal injections (IVI).

METHODS

An observational cross-sectional study was conducted in our tertiary university care center between December 2017 and December 2018. Consecutive patients undergoing IVI were included. A paper survey was completed before and after IVI to assess patient experience. Preoperative anxiety and need for information were assessed using the Amsterdam Preoperative Anxiety Information Scale (APAIS) score.

RESULTS

Hundred patients with a median age of 76.5 years (42-95, SD = 10.1) were included. Median best-corrected visual acuity (BCVA) in both eyes was 0.4 logMAR. Main IVI indications were wet age-related macular degeneration (n = 58), diabetic macular edema (n = 19), and venous occlusion (n = 16). The IVI most unpleasant steps were as follows: using an eyelid retractor, needle entry, changing of physician from one IVI to another, the pre-IVI waiting time, and the high number of IVI required for disease control. Preoperative anxiety (APAIS score ≥ 11) was correlated in the multivariate analysis with the need for information (p = 0.004), changing of ophthalmologist between different IVI sessions (p = 0.006), and pain expected before the IVI (p = 0.010). The need for information (APAIS score ≥ 5) was only associated with the preoperative anxiety in the multivariate analysis (p = 0.001).

CONCLUSION

Preoperative anxiety and need for information are common in patients undergoing IVI even after many IVI. Being injected by different practitioners was strongly correlated with preoperative anxiety and should be avoided as much as possible. Better educational and information programs are needed.

Guidelines for the Management of Retinal Vein Occlusion by the European Society of Retina Specialists (EURETINA)

The high prevalence of cardiovascular disease particularly in the elderly population is associated with retinal vascular disease. Retinal vein occlusions represent severe disturbances of the hypoxia-sensitive neurosensory retina. Acute and excessive leakage leads to the diagnostic hallmarks of retinal hemorrhage and edema with substantial retinal thickening. Advanced diagnostic tools such as OCT angiography allow to evaluate retinal ischemia and identify the risk for late complications and will soon reach clinical routine besides fluorescein angiography. Accordingly, the duration of non-perfusion is a crucial prognostic factor requiring timely therapeutic intervention. With immediate inhibition of vascular leakage, anti-VEGF substances excel as treatment of choice. Multiple clinical trials with optimal potential for functional benefit or a lesser regenerative spectrum have evaluated aflibercept, ranibizumab, and bevacizumab. As retinal vein occlusion is a chronic disease, long-term monitoring should be individualized to combine maintenance with practicability. While steroids may be considered in patients with systemic cardiovascular risk, surgery remains advisable only for very few patients. Destructive laser treatment is an option if reliable monitoring is not feasible. Ophthalmologists are also advised to perform a basic systemic workup to recognize systemic concomitants. The current edition of the EURETINA guidelines highlights the state-of-the-art recommendations based on the literature and expert opinions in retinal vein occlusion.

The effects of temporary intraocular pressure spikes after intravitreal dexamethasone implantation on the retinal nerve fiber layer

Background and objective: The dexamethasone (DEX) implant is known to cause temporary intraocular pressure (IOP) spikes after implantation. The purpose of this study is to determine if IOP spikes after DEX implant cause significant thinning in the retinal nerve fiber layer (RNFL).

Study design, patients, and methods: A total of 306 charts were reviewed with 48 and 21 patients meeting inclusion criteria for the cross-sectional and prospective groups, respectively. Cross-sectional inclusion criteria: IOP spike ≥22 mmHg up to 16 weeks after DEX implant, DEX implant in only 1 eye per patient, and spectral-domain optical coherence tomography (OCT) RNFL imaging of both eyes ≥3 months after IOP spike. Prospective inclusion criteria: OCT RNFL performed within 1 year prior to DEX implantation, IOP spike ≥22 mmHg up to 16 weeks after DEX implant, and OCT RNFL performed ≥3 months after IOP spike. The average RNFL thickness in the contralateral eye was used as the control in the cross-sectional group. Institutional review board approval was obtained.

Results: In the cross-sectional group, there was no statistically significant difference in the mean RNFL thicknesses in the treated vs untreated eyes (80.4±15.5 μm and 82.6±15.8 μm, respectively; P=0.33) regardless of treatment diagnosis, magnitude of IOP spike, or history of glaucoma. In the prospective group, mean RNFL thicknesses before and after IOP spikes ≥22 mmHg were similar (78.0±14.8 μm and 75.6±13.6 μm, respectively; P=0.13).

Conclusion and relevance: Temporary elevation of IOP after DEX implantation when treated with topical IOP lowering drops does not appear to lead to a meaningful change in RNFL thickness.

Recent advances in slow and sustained drug release for retina drug delivery

INTRODUCTION

Striking recent advance has occurred in the field of medical retina, greatly because intraocular drugs have been developed, enhancing their clinical efficacy while avoiding systemic side-effects. However, the burden of repeated intraocular administration makes limits the optimal efficacy of treatments, prompting the development of new drugs with prolonged half-life or of sustained drug delivery systems.

AREAS COVERED

In this review, we describe the various drugs and drug delivery systems that have reached the clinical stage and those that are in clinical development and we discuss the limitations to clinical translation.

EXPERT OPINION

Substantial fundamental work is still required to build guidelines on optimal animal models for ocular pharmacokinetics and safety studies depending on the target disease site and the on the type of therapeutic compounds. The effects of a drug administered as a bolus at high concentration in the vitreous might differ from those resulting from the sustained release of a lower concentration, and no delivery platform can be simply adapted to any drug. For the treatment of retinal diseases, development of therapeutic compounds should integrate from its early conception, the combination of an active drug with a specific drug delivery system, administered by a specific route.

Efficacy and safety of dexamethasone intravitreal implant in patients with retinal vein occlusion resistant to anti-VEGF therapy: a 12-month prospective study

Purpose: To evaluate the safety and efficacy of repeated intravitreal dexamethasone implant (Ozurdex) injections administrated on an "as-needed" protocol for retinal vein occlusion patients with macular oedema, previously subjected to at least five anti-vascular endothelial growth factor (VEGF) injections with poor or no response. Methods: Prospective interventional case series of 13 branch retinal vein occlusion (BRVO) and 10 central retinal vein occlusion (CRVO) patients with persistent macular oedema (>250 μm) after at least five anti-VEGF injections. Exclusion criteria included: baseline visual acuity worse than 1.5 logMAR, previous intravitreal implant, history of vitreoretinal surgery, manifest glaucoma or ocular hypertension, epiretinal membrane, retinal neovascularization, massive retinal or macular ischaemia, vitreous haemorrhage or severe lens opacity, previous laser photocoagulation treatment. Each patient received an initial intraocular dexamethasone implant and the procedure was repeated at 6 months "as needed." Patients were followed up at months 2, 4, 6, 8, 10 and 12 with spectral domain optical coherence tomography and best corrected visual acuity measurements. Exclusion criteria included: baseline visual acuity worse than 1.5 logMAR, previous intravitreal implant, history of vitreoretinal surgery, manifest glaucoma or ocular hypertension, epiretinal membrane, retinal neovascularization, retinal or macular ischaemia, vitreous haemorrhage or severe lens opacity, previous laser photocoagulation treatment. Patients on topical or systemic corticosteroid therapy (during the last 3 months), and known steroid responders as well as diabetic patients were also excluded. Results: In the BRVO group, the mean central retinal thickness (CRT) and best corrected visual acuity (BCVA) significantly improved from 482.92 ± 139.99 μm (0.55 ± 0.12 logMAR) at baseline, to 369.31 ± 119.72 μm (0.43 ± 0.18 logMAR) at 6 months (p = 0.011/p = 0.019). At 12 months CRT was 295.82 ± 135.48 μm (p = 0.026) and BCVA 0.29 ± 0.17 logMAR (p = 0.002). Minimum CRT values were achieved at 3.45 months after the first injection, and 2.46 months after the second injection (197.00 ± 84.27 and 180.00 ± 76.89 μm, respectively). Best BCVA values were achieved at a mean of 4 ± 0.853 months after the first injection, and 4 months after the second injection (0.219 ± 0.129 and 0.222 ± 0.078 logMAR, respectively). In the CRVO group, neither the mean CRT nor BCVA improved significantly at 6 months: from 669.70 ± 203.20 μm (0.80 ± 0.231 logMAR) at baseline, to 586.20 ± 237.63 μm (0.740 ± 0.268 logMAR) at 6 months (p = 0.131/p = 0.333). At 12 months CRT was significantly improved: 549.90 ± 191.26 μm (p = 0.047), but BCVA lacked significant improvement: 0.690 ± 0.285 logMAR (p = 0.072). Minimum CRT values were achieved at a mean of 2 months after the first injection, and also 2 months after the second injection (261.60 ± 121.31 and 280.00 ± 177.43 μm, respectively). Best BCVA values were achieved at a mean of 2 months after the first injection, and 2 months after the second injection and were 0.390 ± 0.173 and 0.385 ± 0.233 logMAR, respectively. Cataract progression was a rare event (2/23 eyes), while transient steroid-induced ocular hypertension (5/23 eyes) was managed successfully with IOP-lowering medication Conclusion: Dexamethasone implant should be considered as an effective and safe alternative in patients with BRVO and CRVO who have failed anti-VEGF therapy. Shortening the re-injection interval especially for CRVO cases should be considered.

Comparison of dexamethasone intravitreal implant with intravitreal anti-VEGF injections for the treatment of macular edema secondary to branch retinal vein occlusion: A meta-analysis

BACKGROUND

This meta-analysis compared the efficacy and safety of dexamethasone intravitreal implant (DEX) and anti-vascular endothelial growth factor (anti-VEGF) in the treatment of macular edema (ME) secondary to branch retinal vein occlusion (BRVO).

METHODS

The PubMed, Embase, Cochrane Library, and Web of Science databases were comprehensively searched for published studies comparing DEX with anti-VEGF for the treatment of ME caused by BRVO. Outcomes of the selected studies included best-corrected visual acuity (BCVA), central macular thickness (CMT), and adverse events. Review Manager (RevMan) 5.3 was used to analyze the data.

RESULTS

Six trials comparing the efficacy and safety of DEX with anti-VEGF were included in this meta-analysis. At 1 month, DEX achieved a mean BCVA superior to that achieved by anti-VEGF (MD = -0.11, P < .0001), in addition to a superior mean BCVA change (MD = -0.35, P < .00001). At 3 months, the mean BCVA showed a significant difference (MD = -0.06, P = .03) between DEX and anti-VEGF treatment, while the mean BCVA change was similar to that with anti-VEGF treatment (MD = -0.06, P = .11). However, neither mean BCVA nor mean BCVA change showed a significant difference between DEX and anti-VEGF treatment at 6 months (MD = 0.08, P = .06; MD = 0.06, P = .43, respectively). Mean CMT and mean CMT change were significantly lower in the DEX group than in the anti-VEGF group at 1 month (MD = -53.63 μm, P < .00001; MD = -60.1 μm, P = .005, respectively). However, at 3 months, mean CMT and mean CMT change were similar between DEX and anti-VEGF treatment (MD = 17.4 μ, P = .74; MD = 18.01 μm, P = .72, respectively). Although mean CMT in the anti-VEGF group was not significantly lower than that in the DEX group at 6 months (MD = 55.53, P = .07), the mean CMT change from baseline achieved by the anti-VEGF treatment was significantly superior to that obtained with DEX (MD = 75.53, P = .0002). Concerning adverse events, no statistically significant differences were observed in the incidence of cataract (OR = 4.25, P = .07), but the use of DEX led to a higher risk of intraocular pressure elevation compared with anti-VEGF treatment (OR = 12.04, P = .006).

CONCLUSIONS

Our results show that visual acuity recovery and CMT were better in the DEX group than in the anti-VEGF group after 1 and 3 months, although the difference in CMT at 3 months was not significant. However, there were no significant differences in terms of visual acuity and CMT between the two groups after 6 months of follow-up. Therefore, DEX may be recommended as the first treatment option in ME associated with BRVO.

Safety of 6000 intravitreal dexamethasone implants

PURPOSE

To evaluate the real-life safety profile of intravitreal dexamethasone implant injection for various retinal conditions.

METHODS

Retrospective multicenter analysis of intravitreal dexamethasone implant injections (700 µg) due to various retinal conditions including central retinal venous occlusion (1861 injections), diabetic macular oedema (3104 injections), post-surgical cystoid macular oedema (305 injections) and uveitis (381 injections). The eyes were evaluated mainly for the occurrence of adverse events such as glaucoma, cataract, retinal detachment and endophthalmitis along during the follow-up period.

RESULTS

A total of 6015 injections in 2736 eyes of 1441 patients (mean age of 65.7±12.9 years) were in total analysed over an average period of 18 months (range 6 months to 102 months). A total of 576 eyes (32.5% of the phakic eyes) developed cataract requiring surgical intervention. However, visually insignificant cataract progression was observed in another 259 phakic eyes (14.6%) which did not require surgical removal. A total of 727 eyes (26.5%) experienced an intraocular pressure (IOP) rise of >25 mm Hg, with 155 eyes (5.67%) having a prior history of glaucoma and 572 eyes (20.9%) having new onset IOP rise. Overall, more than 90% of eyes with IOP rise were managed medically, and 0.5% eyes required filtering surgery. Endophthalmitis (0.07%), retinal detachment (0.03%) and vitreous haemorrhage (0.03%) were rare. There was no significant change in visual acuity (p=0.87) and central macular thickness (p=0.12) at the last follow-up.

CONCLUSION

This is the largest real-life study assessing the safety of intravitreal dexamethasone implant injections in various retinal conditions. Cataract progression and intraocular pressure rise are the most common side effects, but are often rather easily manageable.

Treatment of refractory diabetic macular edema with a fluocinolone acetonide implant in vitrectomized and non-vitrectomized eyes

AIM

To report real-life data on the use of an intravitreal fluocinolone acetonide implant in the treatment of refractory diabetic macular edema (DME) in pars plana vitrectomized (PPV) and non-PPV eyes.

METHODS

This was a comparative retrospective observational study of 23 eyes with chronic DME. Best-corrected visual acuity (BCVA) and central macular thickness (CMT) were recorded at baseline, 1, 4 and 12mo. Descriptive statistics and non-parametric tests were performed to analyze and compare PPV and non-PPV eyes.

RESULTS

Seven PPV and 16 non-PPV eyes were included in the study. Median BCVA in the non-PPV group varied from 0.65 logMAR [Interquartile range (IQR): 0.40] at baseline to 0.42 logMAR (IQR: 0.40) at 12mo. Median CMT varied from 430 µm (IQR: 131.3) at baseline to 317 µm (IQR: 107.5) at 12mo. Median BCVA in the PPV group varied from 0.60 logMAR (IQR: 0.62) at baseline to 0.74 logMAR (IQR: 0.34) at 12mo. Median CMT varied from 483 µm (IQR: 146) at baseline to 397 µm (IQR: 132) at 12mo. Of 0/7 eyes and 1/16 eyes in the PPV and non-PPV eyes respectively had a baseline visual acuity of 6/12 or better (0.3 logMAR). At last follow up, 1/7 and 5/16 eyes in the PPV and non-PPV group respectively achieved a visual acuity of 6/12 or better.

CONCLUSION

Visual outcomes are modest following the use of the fluocinolone acetonide implant for chronic DME. The steroid implant is a useful treatment option in the management of refractory DME in vitrectomized and non-vitrectmized eyes.

Polyester elastomers for soft tissue engineering

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

The efficacy of intravitreal dexamethasone implant as the first-line treatment for retinal vein occlusion-related macular edema in a real-life scenario

Purpose

This study evaluated the effect of intravitreal dexamethasone implant (IDI; Ozurdex) injection for treating macular edema in patients with branch retinal vein occlusion (BRVO) or central retinal vein occlusion (CRVO).

Methods

This prospective study included 40 eyes of 40 patients with nonischemic BRVO and 31 eyes of 31 patients with nonischemic CRVO who received IDI injection as the first-line treatment for macular edema. The best-corrected visual acuity (BCVA) value before and after the treatment; intraocular pressure; optic coherence tomography findings; and all ocular examination findings, including central foveal thickness (CFT) measurement and fluorescein angiography findings, were evaluated for each patient.

Results

After the IDI injection, BCVA value increased (P < 0.001) and CFT value decreased (P < 0.001) in both groups. The recurrence rates of CFT elevation after the first and the second Ozurdex injections were 65.0% and 65.3%, respectively, in patients with BRVO and 70.9% and 68.1%, respectively, in patients with CRVO. A statistically significant correlation was observed between preinjection CFT value and postinjection recurrence of CFT elevation (P = 0.017).

Conclusion

Treatment with the IDI injections resulted in significant short-term improvement in CFT and BCVA values in patients with clinically significant RVO-related macular edema. Moreover, we observed that high preinjection CFT value was associated with a risk of postinjection recurrence of CFT elevation.

Safety and efficacy of dexamethasone intravitreal implant for treatment of macular edema secondary to retinal vein occlusion in Chinese patients: randomized, sham-controlled, multicenter study

PURPOSE

The purpose of this study was to evaluate the safety and efficacy of dexamethasone intravitreal implant 0.7 mg (DEX) for treatment of macular edema associated with retinal vein occlusion (RVO).

METHODS

This study was a six-month, randomized, double-masked, sham-controlled, multicenter, phase 3 clinical trial with a 2-month open-label study extension. Patients with branch or central RVO received DEX (n = 129) or sham procedure (n = 130) in the study eye at baseline; all patients who met re-treatment criteria received DEX at month 6. Efficacy measures included Early Treatment Diabetic Retinopathy Study (ETDRS), best-corrected visual acuity (BCVA), and central retinal thickness (CRT) on optical coherence tomography.

RESULTS

Time to ≥15-letter BCVA improvement from baseline during the first 6 months (primary endpoint) was earlier with DEX than sham (p < 0.001). At month 2 (peak effect), the percentage of patients with ≥15-letter BCVA improvement from baseline was DEX: 35%, sham: 12%; mean BCVA change from baseline was DEX: +10.6 letters, sham: +1.7 letters; and mean CRT change from baseline was DEX: -407 μm, sham: -62 μm (all p < 0.001). Outcomes were better with DEX than sham in both branch and central RVO. The most common treatment-emergent adverse event was increased intraocular pressure (IOP). Increases in IOP generally were controlled with topical medication. Mean IOP normalized by month 4, and no patient required incisional glaucoma surgery.

CONCLUSIONS

DEX had a favorable safety profile and provided clinically significant benefit in a Chinese patient population with RVO. Visual and anatomic outcomes were improved with DEX relative to sham for 3-4 months after a single implant.

Dexamethasone Intravitreal Implant in Diabetic Macular Edema: Real-Life Data from a Prospective Study and Predictive Factors for Visual Outcome

INTRODUCTION

The purpose of the study was to evaluate the long-term anatomical and functional outcomes in patients with diabetic macular edema (DME) treated with intravitreal dexamethasone implant and to determine the predictive factors for the final visual outcome.

METHODS

The study included 54 patients with DME refractory to previous antivascular endothelial growth factor (anti-VEGF) who were treated with intravitreal dexamethasone implant. Predictive factors for visual outcome were assessed. In addition, the change in best-corrected visual acuity (BCVA) and the percentage of patients with edema resolution were evaluated.

RESULTS

At the end of the 12-month follow-up, patients with DME gained + 5.2 letters (about 1 Snellen line), while 57.4% of patients presented total resolution of macular edema. Negative predictive factors for the final visual outcome were found to be increasing age, increasing macular thickness, phakic status, the presence of intraretinal fluid, hyperreflective foci, hard exudates, as well as external limiting membrane and ellipsoid zone disruption. The mean number of injections was 2.1.

CONCLUSIONS

The various predictive factors that determine the visual outcome and possibly define patient prognosis after dexamethasone intravitreal implant in DME cases have been studied. The long follow-up showed that dexamethasone intravitreal implant seems to be a safe and effective treatment for this disease, requiring a limited number of injections.

Real-life clinical data for dexamethasone and ranibizumab in the treatment of branch or central retinal vein occlusion over a period of six months

PURPOSE

To evaluate the therapeutic outcome for dexamethasone implant (DEX) or intravitreal ranibizumab (IVR) injections over 6 months in patients with macular edema due to branch or central retinal vein occlusion (BRVO, CRVO), in a real-life setting.

METHODS

A total of 107 patients with BRVO or CRVO were included into this retrospective single-center observational study. Patients were treated with monotherapy consisting of DEX or three monthly IVR injections following a pro re nata regimen (PRN). Best-corrected visual acuity (BCVA), central retinal thickness (CRT) and intraocular pressure (IOP) were compared between the two therapy groups after 1, 3 and 6 months.

RESULTS

BRVO patients treated with DEX achieved a statistically significant gain in BCVA measured in logMAR after 1 month (mean gain, 95% CI: 0.21, 0.08-0.34, p = 0.001), 3 months (0.16, 0.03-0.28, p = 0.012) and 6 months (0.19, 0.07-0.32, p = 0.002), whereas patients treated with IVR showed a statistically significant BCVA gain in month 3 (mean improvement, 95% CI: 0.13, 0.01-0.26, p = 0.039) and month 6 (0.16, 0.03-0.29, p = 0.018). BCVA in CRVO patients with DEX worsened slightly at month 6 (mean worsening, 95% CI: -0.08, -0.24 to 0.08, p = 0.305), while IVR treated-patients achieved a statistically significant BCVA gain at 3 months (mean improvement, 95% CI: 0.14, 0.02-0.25, p = 0.021). Both therapies were accompanied by statistically significant CRT reductions of 150 to 200 μm (median). Adverse events reported were predictable and limited.

CONCLUSIONS

In a clinical setting, comparable improvement in BCVA and CRT were observed after DEX and IVR injections for treatment of BRVO. CRVO patients showed greater benefit with IVR.