Three-Year, Randomized, Sham-Controlled Trial of Dexamethasone Intravitreal Implant in Patients with Diabetic Macular Edema

A 12-MONTH, SINGLE-MASKED, RANDOMIZED CONTROLLED STUDY OF EYES WITH PERSISTENT DIABETIC MACULAR EDEMA AFTER MULTIPLE ANTI-VEGF INJECTIONS TO ASSESS THE EFFICACY OF THE DEXAMETHASONE-DELAYED DELIVERY SYSTEM AS AN ADJUNCT TO BEVACIZUMAB COMPARED WITH CONTINUED BEVACIZUMAB MONOTHERAPY

PURPOSE

To determine whether a dexamethasone intravitreal implant 0.7 mg (dexamethasone delivery system [DDS], Ozurdex) combined with bevacizumab 1.25 mg (Avastin) provides greater benefit than bevacizumab monotherapy in eyes with diabetic macular edema with incomplete response to multiple antivascular endothelial growth factor injections.

METHODS

Eyes with diabetic macular edema were randomly assigned to receive combination therapy (bevacizumab plus DDS) or bevacizumab monotherapy. Combination therapy eyes received intravitreal bevacizumab at baseline, DDS at Month 1, and subsequent DDS (at Months 5 and 9), whereas monotherapy eyes received bevacizumab (monthly) if indicated. Eyes were eligible for retreatment if the central subfield thickness measured >250 μm, and Early Treatment of Diabetic Retinopathy Study visual acuity was <80 letters (20/25).

RESULTS

Forty eyes of 30 patients were enrolled. The mean visual acuity changes from baseline to 12 months were similar in the 2 groups (combined: +5.4 letters; bevacizumab: +4.9 letters; difference = 0.2 letters, 95% confidence interval = -5.9 to 6.3; P = 0.75). The mean reduction in central subfield thickness was greater in the combination group (-45 μm vs. -30 μm, difference = 69 μm, 95% confidence interval = 9-129; P = 0.03) and more patients in the combination group had central subfield thickness <250 μm. The combined treatment group received three fewer supplemental injections of bevacizumab, but this was counterbalanced by the need for an average of 2.1 DDS injections.

CONCLUSIONS

The dexamethasone implant combined with bevacizumab significantly improves visual acuity and significantly improves macular morphology in eyes with refractory diabetic macular edema, although visual acuity changes are not superior to continued bevacizumab monotherapy.

Fluocinolone acetonide for the treatment of diabetic macular edema

In addition to VEGF inhibitors such as ranibizumab, aflibercept or bevacizumab, clinical and experimental investigations have revealed the great potential of steroids in the treatment of DME. At present two intravitreal steroid inserts are approved for the treatment of DME containing either dexamethasone or fluocinolone acetat (FA) as a pharmacological compound. The non degradable intravitreal FA insert releases 0.2 µg FA per day (Iluvien, Alimera Sciences). Clinical phase III studies have demonstrated the beneficial effect of the FA insert to last up to three years, especially in patients with a prolonged history of DME of at least three years at the initiation of therapy. While the treatment appears to be well tolerated over all, side effects such as cataract formation in nearly all treated phakic patients and raise of intraocular pressure need to be discussed with the patients as potential complications of the treatment.

Treatment strategies for refractory diabetic macular edema: switching anti-VEGF treatments, adopting corticosteroid-based treatments, and combination therapy

INTRODUCTION

The pathophysiology of diabetic macular edema (DME) is complex, involving vascular endothelial growth factor (VEGF) and other inflammatory mediators. DME is currently treated first-line with intravitreal anti-VEGF treatments, though some cases are refractory to multiple anti-VEGF treatments.

AREAS COVERED

This article examines the evolution of treatment practices for DME, with discussion of the recent studies that guide treatment for refractory cases of DME. A literature search was performed using the following terms: anti-VEGF, DME, aflibercept, bevacizumab, ranibizumab, refractory macular edema, and VEGF.

EXPERT OPINION

Focal extrafoveal DME may be treated first-line with laser. In patients with center-involving DME and only mild vision loss, consider starting treatment with bevacizumab, especially when cost is an issue, whereas aflibercept may be considered more strongly in patients with moderate visual loss or worse. There are no standard protocols that define 'treatment failure,' but several studies have reported that switching from bevacizumab to either ranibizumab or aflibercept will result in further reduction of CSFT and improvement in BCVA. Further study with prospective randomized trials is warranted to validate these findings. Switching to intravitreal corticosteroids may be of particular benefit to pseudophakic patients. Anti-VEGF combination with sustained-release corticosteroids also appears promising for refractory DME.

Ocular Complications of Diabetes and Therapeutic Approaches

Diabetes mellitus (DM) is a metabolic disease defined by elevated blood glucose (BG). DM is a global epidemic and the prevalence is anticipated to continue to increase. The ocular complications of DM negatively impact the quality of life and carry an extremely high economic burden. While systemic control of BG can slow the ocular complications they cannot stop them, especially if clinical symptoms are already present. With the advances in biodegradable polymers, implantable ocular devices can slowly release medication to stop, and in some cases reverse, diabetic complications in the eye. In this review we discuss the ocular complications associated with DM, the treatments available with a focus on localized treatments, and what promising treatments are on the horizon.

The combination of phacoemulsification surgery and intravitreal triamcinolone injection in patients with cataract and diabetic macular edema

PURPOSE

To assess the safety and efficiency of combined phacoemulsification (PHACO) surgery and intravitreal triamcinolone (IVTA) injection with or without macular grid laser photocoagulation in patients with cataract and diabetic macular edema.

MATERIAL AND METHODS

This prospective study included 41 eyes of 36 diabetic patients with cataract and coexisting clinically significant macular edema (CSME). After PHACO and IVTA injection eyes were divided into two groups: the laser and IVTA group (Group 1) and only IVTA group (Group 2). Preoperative and postoperative best corrected visual acuity (BCVA), central macular thickness (CMT), and intraocular pressure (IOP) were recorded. Paired sample t-test was used to compare data in the groups and C square test for qualitative variables.

RESULTS

Postoperative BCVA was significantly higher than the initial BCVA during the follow-up period in both groups (p < 0.01). The BCVA 6 months after surgery was significantly higher in group 1 than in group 2 (p < 0.01). There was no statistically significant difference in IOP between two groups preoperatively and postoperatively during the follow-up period (p > 0.05). There was no statistically significant difference between both groups in mean CMT preoperatively and 2nd week, 2nd month and 3rd month after surgery (p > 0.05). The mean CMT 6 months after surgery was statistically significantly lower in group 1 than in group 2 (p < 0.01).

CONCLUSIONS

PHACO surgery combined with IVTA injection improves BCVA and provides a decrease in CMT in diabetic patients with CSME. Additional macular grid laser photocoagulation after surgery helps to preserve this improvement in BCVA and decrease in CMT.

Morphology and Function over a One-Year Follow Up Period after Intravitreal Dexamethasone Implant (Ozurdex) in Patients with Diabetic Macular Edema

Background

To investigate changes in macular morphology and function after an intravitreal dexamethasone implant for diabetic macular edema (DME).

Methods

Twenty-seven eyes in 27 treatment-naive patients affected by DME were treated with intravitreal Ozurdex® injections (IVOI) and followed up 12 months to evaluate morphological and functional changes by means of best-corrected visual acuity (BCVA), microperimetry (MP1), multifocal electroretinography (mfERG), pattern electroretinography (PERG) and spectral domain optical coherence tomography (SD-OCT).

Results

Both BCVA and retinal sensitivity improved significantly at one month after the IVOI (p = 0.031 and p<0.0001, respectively). After five months, the improvement of BCVA remained statistically significant compared with baseline values (p = 0.022); retinal sensitivity improvement was statistically significant for up to four months after the IVOI (p = 0.059). Moreover, central macular thickness significantly decreased for up to four months. Interestingly, PERG and mfERG values did not change significantly for up to four months post-IVOI, but then began to worsen.

Conclusions

In eyes with DME, intravitreal dexamethasone implant determined morphological and functional improvement as soon as one month and for up to four months after the treatment.

Dexamethasone intravitreal implant for treatment of persistent macular oedema in Birdshot retinochoroidopathy

CLINICAL CASE

The case is reported of a 32 year-old man with a bilateral cystoid macular oedema and serous macular detachment due to birdshot retinochoroidopathy. An intravitreal implant of 0.7 mg dexamethasone (Ozurdex®, Allergan) was performed on both eyes, after a partial response of the macular oedema to oral and subtenon corticosteroids. Anatomical and visual improvements were observed and maintained after six months of follow up.

DISCUSSION

Intravitreal dexamethasone implant may be a good therapeutic option in patients with macular oedema due to Birdshot retinochoroidopathy, and who were refractory or had intolerance to previous therapies.

Efficacy of single-dose dexamethasone implantation in patients with persistent diabetic macular edema

To investigate the efficacy of single-dose intravitreal dexamethasone implantation in the treatment of persistent diabetic macular edema (DME) unresponsive to 3 consecutive ranibizumab injections over a period of 6 months. Forty-one patients with a previous history of treatment for DME including at least three consecutive intravitreal ranibizumab injections were enrolled in this retrospective study. Main outcome measures were change in best-corrected visual acuity (BCVA), central macular thickness (CMT), and intraocular pressure from baseline to 6th month. At the baseline, the mean CMT was 572.4 ± 123.1 μm which improved to 264.2 ± 114.4, 317.7 ± 141.7, 410.6 ± 169.1, and 382.8 ± 181.5 μm at the 1st, 3rd, 5th, and 6th month, respectively (p < 0.05). The preoperative mean BCVA was 0.85 ± 0.54 logMAR units which improved to 0.76 ± 0.5 (p = 0.08), 0.69 ± 0.4 (p = 0.02), 0.74 ± 0.4 (p = 0.284), and 0.72 ± 0.3 (p = 0.489) logMAR units at the 1st, 3rd, 5th, and 6th months, respectively. Additional injections were required for 13 (31 %) eyes at 3rd month and 14 (34 %) eyes at 5th month due to recurrence of macular edema. Intravitreal dexamethasone implantation caused a significant improvement of BCVA and reduction of CMT in the patients with persistent DME that were unresponsive to 3 consecutive ranibizumab injections. However, retreatment before 6 months in the majority of the patients was needed despite the beneficial effects after the index procedure.

Steroids in Central Retinal Vein Occlusion: Is There a Role in Current Treatment Practice?

With the current widespread use of anti-VEGFs in the treatment of central retinal vein occlusion (CRVO), the role for steroids has become greatly diminished. Recent large scale randomized control trials (RCTs) have established the efficacy and safety of anti-VEGFs in the treatment of CRVO. Steroids are known to cause elevations in intraocular pressure as well as increase the risk of cataract formation. With that in mind many ophthalmologists are injecting steroids less frequently. This paper aims to review some of the data pertaining to the use of steroids either as a first line monotherapy, adjunct therapy, or an alternative therapy to help answer the question: Is there currently any role for steroids in the management of CRVO?

INTRAVITREAL CORTICOSTEROIDS IN DIABETIC MACULAR EDEMA: PHARMACOKINETIC CONSIDERATIONS

PURPOSE

To review the relationship between kinetics, efficacy, and safety of several corticosteroid formulations for the treatment of diabetic macular edema.

METHODS

Reports of corticosteroid use for the treatment of diabetic macular edema were identified by a literature search, which focused on the pharmacokinetics, efficacy, and safety of these agents in preclinical animal models and clinical trials.

RESULTS

Available corticosteroids for diabetic macular edema treatment include intravitreal triamcinolone acetonide, dexamethasone, and fluocinolone acetonide. Because of differences in solubility and bioavailability, various delivery mechanisms are used. Bioerodible delivery systems achieve higher maximum concentrations than nonbioerodible formulations. There is a relationship between visual gains and drug persistence in the intravitreal compartment. Safety effects were more complex; level of intravitreal triamcinolone acetonide exposure is related to development of elevated intraocular pressure and cataract; this does not seem to be the case for dexamethasone, where two different doses showed similar mean intraocular pressure and incidence of cataract surgery. With fluocinolone acetonide, rates of intraocular pressure elevations requiring surgery seem to be dose related; rates of cataract extraction were similar regardless of dose.

CONCLUSION

Available corticosteroids for diabetic macular edema exhibit different pharmacokinetic profiles that impact efficacy and adverse events and should be taken into account when developing individualized treatment plans.

Dexamethasone implant in diabetic macular edema in real-life situations

PURPOSE

To report outcome of eyes with recalcitrant and naive eyes with diabetic macular edema (DME) treated with intravitreal dexamethasone implants (Ozurdex) injection.

METHODS

Retrospective multicenter data analysis of eyes with DME treated with Ozurdex implant and with minimum follow-up of at least one year after the first implant. Data collected included demographic details, history of presenting illness, past treatment history, clinical examination details including visual acuity at presentation, and follow-up with imaging and treatment details. Paired sample t-test was used to measure mean differences between pre- and post-implant values obtained at baseline and last follow-up.

RESULTS

A total of 79 eyes (62 subjects) were included. Sixty-four eyes had been previously treated; 15 eyes were naive. Among the previously treated eyes, mean interval between first Ozurdex injection and any previous treatment was 7.69±8.2 months. In naive eyes, the visual acuity improved from baseline 0.58±0.25 to 0.44±0.33 logMAR at last follow-up (P=0.05). In eyes that had been previously treated, the improvement was from 0.65±0.34 at baseline to 0.48±0.35 logMAR (P=0.01). Mean treatment-free interval was 6.5±4.5 months. Nine eyes were steroid responder with controlled intraocular pressure (IOP), none showed any spike in IOP during the follow-up period.

CONCLUSIONS

Ozurdex implant could be a good alternative for recalcitrant as well as naive eyes with DME. The visual gain after initial implant injection was fairly maintained, with additional treatment usually after 6 months in naive eyes. Ozurdex appeared safe even in steroid responders with good control of IOP with antiglaucoma medications.

Anatomical effects of dexamethasone intravitreal implant in diabetic macular oedema: a pooled analysis of 3-year phase III trials

BACKGROUND/AIM

To assess long-term effects of dexamethasone intravitreal implant (DEX implant) monotherapy on retinal morphology in diabetic macular oedema (DME).

METHODS

Two multicentre, masked, phase III studies with identical protocols randomised patients with DME, best-corrected visual acuity of 34-68 Early Treatment Diabetic Retinopathy Study letters and central subfield retinal thickness (CSRT) ≥300 µm to DEX implant 0.7, 0.35 mg or sham procedure. Patients were followed up for 3 years (39 months if treated at month 36), with retreatment allowed at ≥6-month intervals. Patients needing other macular oedema (ME) therapy exited the study. Changes from baseline in CSRT, macular volume and ME grade, area of retinal thickening, macular leakage, macular capillary loss and diabetic retinopathy severity were assessed.

RESULTS

After 3 years, more eyes treated with DEX implant 0.7 and 0.35 mg than sham showed improvement (although small) in ME grade (p<0.05 vs sham). DEX implant 0.7 mg delayed time to onset of two-step progression in diabetic retinopathy severity by ∼12 months. DEX implant 0.7 and 0.35 mg produced small, non-sustained reductions in macular leakage but had no significant effect on macular capillary loss.

CONCLUSIONS

DEX implant 0.7 or 0.35 mg, administered at ≥6-month intervals over 3 years, produced sustained retinal structural improvement in DME.

TRIAL REGISTRATION NUMBER

NCT00168337 and NCT00168389.

Curing diabetic retinopathy: Is a strategy emerging?

Diabetic macular edema (DME) is the leading cause of blindness among working aged individuals of industrialized countries. The Early Treatment of Diabetic Retinopathy Studies (ETDRS) demonstrated that timely laser photocoagulation significantly decreases vision loss from DME, thereby establishing laser as standard- of- care for over 2 decades. Unfortunately, only a minority of patients treated in the ETDRS experienced significant improvements in visual acuity (VA), leaving researchers to look for more effective interventions. The recently introduced drugs (ranibizumab, aflibercept) that prevent the binding of vascular endothelial growth factor (VEGF) to its trans-membrane receptors produce superior improvements in VA over laser, either when administered as monotherapy or when combined with as-needed supplemental macular laser photocoagulation. The pivotal phase III trials featured monthly (ranibizumab, aflibercept) or bimonthly (aflibercept) injections of each drug for 2 years during which a significant number of patients experienced improved diabetic retinopathy (DR) severity scores. The need for anti-VEGF injections dropped significantly after 1-3 years in both the RISE/RIDE and DRCR.net Protocol I trials indicating that VEGF production had diminished. These data led to the FDA approval of both ranibizumab and aflibercept for the treatment of DR complicated by DME. Physicians may now treat vision-threatening DME with ranibizumab or aflibercept while simultaneously improving DR and possibly achieving long-term regression.

Repeated intravitreal dexamethasone implant (Ozurdex) for diabetic macular edema

PURPOSE

To evaluate the effects of repeated intravitreal dexamethasone implant.

METHODS

We reviewed the charts of 12 patients with diabetic macular edema, who received at least 2 intravitreal Ozurdex (0.7 mg) on an "as needed" basis. Main outcome measures included changes in best-corrected visual acuity, central macular thickness, retreatment interval, and incidence of side effects.

RESULTS

A total of 15 eyes of 12 patients (6 men, 6 women; mean age 62 ± 12 years) were included. Retreatment was judged necessary after mean of 7.8 ± 4.1 months from the first Ozurdex (median, 6 months) (15 of 15 eyes), mean of 4.8 ± 0.9 months from the second Ozurdex (median, 5 months) (7 of 15 eyes), mean of 5.3 ± 1.5 months from the third Ozurdex (median, 5 months) (3 of 15 eyes), and mean of 5.6 ± 2 months from the fourth Ozurdex (median, 5 months) (3 of 15 eyes). Mean baseline best-corrected visual acuity was 0.67 ± 0.33 logMAR in the overall diabetic macular edema population; it significantly improved to 0.53 ± 0.31 logMAR after mean of 40.9 ± 18.2 days from the first Ozurdex (peaking efficacy) (P < 0.001), to 0.53 ± 0.29 logMAR after mean of 34.4 ± 9.0 days from the second Ozurdex (peaking efficacy) (P < 0.003), and stabilized to 0.62 ± 0.26 logMAR after mean of 29.8 ± 12.1 days from the third Ozurdex (peaking efficacy) (P = 0.05), to 0.5 ± 0.26 logMAR after mean of 36.3 ± 3.2 days from the fourth Ozurdex (peaking efficacy) (P = 0.2), and to 0.50 ± 0.26 logMAR after mean of 37.0 ± 2.6 days from the fifth Ozurdex (peaking efficacy) (P = 0.2). Mean baseline central macular thickness significantly decreased from 546 ± 139 μm to 292 ± 43 μm at 39.4 ± 17.9 days from the first Ozurdex (peaking efficacy) (P < 0.001), to 297 ± 47 μm at 33 ± 9.4 days from the second Ozurdex (peaking efficacy) (P < 0.001), to 293 ± 22 μm at 29.8 ± 12.1 days from the third Ozurdex (peaking efficacy) (P = 0.01), and stabilized to 309 ± 35 μm at 36.3 ± 3.2 days from the fourth Ozurdex (peaking efficacy) (P = 0.1), and to 295 ± 7 μm at 37.0 ± 2.6 days from the fifth Ozurdex (peaking efficacy) (P = 0.1). No serious adverse events were observed; three eyes developed a transient intraocular pressure increase, and cataract was extracted in one eye.

CONCLUSION

Repeated intravitreal Ozurdex on an "as needed" basis with a variable retreatment interval may produce long-term clinically meaningful benefits in the treatment of diabetic macular edema, without other significant side effects than expected after intraocular corticosteroid treatment.

Nonbiological pharmacotherapies for the treatment of diabetic macular edema

INTRODUCTION

During the past decade, there have been significant advances in the pharmacotherapies for the treatment of diabetic macular edema (DME). Among the presently available treatment options, anti-vascular endothelial growth factors (anti-VEGF) agents are the most favored agents due to their efficacy and safety. The index review focuses on nonbiological therapies that have entered in phase 3 clinical trials for DME.

AREAS COVERED

An extensive review of the literature was performed to identify various nonbiological immunotherapies i.e., drugs other than '-mAbs' (monoclonal antibodies including anti-VEGF agents), '-mibs' (proteasome inhibitors), '-NAbs' (nanoparticle albumin-bound), and '-nibs' (small molecule inhibitor/tyrosine kinase inhibitors), among others. Extended-release low-dose corticosteroid devices have been recently approved for the treatment of DME. Other compounds such as non-steroidal anti-inflammatory drugs, antibody mimetic proteins, nonbiological growth factor inhibitors, and inhibitors of protein kinase C have been described.

EXPERT OPINION

A number of therapies are under development for the pharmacological management of DME. Due to the rising healthcare costs associated with anti-VEGF agents, a number of alternate treatment options have been explored recently. Some of these agents have reached phase 3 in clinical trials and appear to have a promising role in the management of DME. As further research is conducted, the role of each individual agent will become more defined, alone or in combination therapy.

Sustained-release steroids for the treatment of diabetic macular edema

Glucocorticoids have been used for decades in the treatment of ocular disorders via topical, periocular, and more recently intravitreal routes. However, their exact mechanisms of action on ocular tissues remain imperfectly understood. Fortunately, two recently approved intravitreal sustained-release drug delivery systems have opened new perspectives for these very potent drugs. To date, among other retinal conditions, their label includes diabetic macular edema, for which a long-lasting therapeutic effect has been demonstrated both morphologically and functionally in several randomized clinical trials. The rate of ocular complications of intravitreal sustained-release steroids, mainly cataract formation and intraocular pressure elevation, is higher than with anti-vascular endothelial growth factor agents. Yet, a better understanding of the mechanisms underlying these adverse effects and the search for the minimal efficient dose should help optimize their therapeutic window.

Dexamethasone intravitreal implant in previously treated patients with diabetic macular edema: subgroup analysis of the MEAD study

Background

Dexamethasone intravitreal implant 0.7 mg (DEX 0.7) was approved for treatment of diabetic macular edema (DME) after demonstration of its efficacy and safety in the MEAD registration trials. We performed subgroup analysis of MEAD study results to evaluate the efficacy and safety of DEX 0.7 treatment in patients with previously treated DME.

Methods

Three-year, randomized, sham-controlled phase 3 study in patients with DME, best-corrected visual acuity (BCVA) of 34–68 Early Treatment Diabetic Retinopathy Study letters (20/200–20/50 Snellen equivalent), and central retinal thickness (CRT) ≥300 μm measured by time-domain optical coherence tomography. Patients were randomized to 1 of 2 doses of DEX (0.7 mg or 0.35 mg), or to sham procedure, with retreatment no more than every 6 months. The primary endpoint was ≥15-letter gain in BCVA at study end. Average change in BCVA and CRT from baseline during the study (area-under-the-curve approach) and adverse events were also evaluated. The present subgroup analysis evaluated outcomes in patients randomized to DEX 0.7 (marketed dose) or sham based on prior treatment for DME at study entry.

Results

Baseline characteristics of previously treated DEX 0.7 (n = 247) and sham (n = 261) patients were similar. In the previously treated subgroup, mean number of treatments over 3 years was 4.1 for DEX 0.7 and 3.2 for sham, 21.5 % of DEX 0.7 patients versus 11.1 % of sham had ≥15-letter BCVA gain from baseline at study end (P = 0.002), mean average BCVA change from baseline was +3.2 letters with DEX 0.7 versus +1.5 letters with sham (P = 0.024), and mean average CRT change from baseline was −126.1 μm with DEX 0.7 versus −39.0 μm with sham (P < 0.001). Cataract-related adverse events were reported in 70.3 % of baseline phakic patients in the previously treated DEX 0.7 subgroup; vision gains were restored following cataract surgery.

Conclusions

DEX 0.7 significantly improved visual and anatomic outcomes in patients with DME previously treated with laser, intravitreal anti-vascular endothelial growth factor, intravitreal triamcinolone acetonide, or a combination of these therapies. The safety profile of DEX 0.7 in previously treated patients was similar to its safety profile in the total study population.

Trial registration

ClinicalTrials.gov NCT00168337 and NCT00168389, registered 12 September 2005

A randomized clinical trial comparing fixed vs pro-re-nata dosing of Ozurdex in refractory diabetic macular oedema (OZDRY study)

OBJECTIVE

To compare the clinical effectiveness and safety of 5-monthly fixed dosing vs pro-re-nata (PRN) Ozurdex treatment in patients with refractory diabetic macular oedema (DMO).

DESIGN

Prospective, multicentre, randomized active-controlled non-inferiority clinical trial.

PARTICIPANTS

Participants were 100 patients who attended Medical Retina Clinics for management of centre-involving refractory DMO.

INTERVENTIONS

Participants were randomized 1 : 1 to either 5-monthly fixed dosing or optical coherence tomography (OCT)-guided PRN regimen of Ozurdex therapy for DMO. Data were collected on best-corrected visual acuity (BCVA), patient-reported outcome measures (PROM), macular thickness and morphology, diabetic retinopathy status, number of injections and adverse events from baseline for a period of 12 months.Main outcome measuresThe primary outcome was the difference between arms in change in BCVA from baseline to 12 months. The prespecified non-inferiority margin was five ETDRS letters. Key secondary outcomes included change in PROM scores, change in macular thickness, change in retinopathy and macular morphology, and safety profile.

RESULTS

The mean change in BCVA was +1.48 (SD 14.8) in the fixed arm vs -0.17 (SD 13.1) in the PRN arm, with adjusted effect estimate +0.97, 90% confidence interval (-4.01, +5.95), P=0.02 (per protocol analysis). The conclusions of the ITT analysis were primarily supportive, -0.34 (-5.49, 4.81) P=0.07, but sensitive to an alternative assumption on missing data, +0.28 (-4.72, 5.27) P=0.04.

CONCLUSIONS

The mean change in BCVA with 5-monthly fixed dosing of Ozurdex was non-inferior to OCT-guided PRN Ozurdex therapy for refractory DMO based on a per protocol analysis.

A prospective randomised controlled clinical trial comparing a combination of repeated intravitreal Ozurdex and macular laser therapy versus macular laser only in centre-involving diabetic macular oedema (OZLASE study)

BACKGROUND/AIMS

To evaluate the clinical efficacy and safety of combined repeated Ozurdex and macular laser therapy (MLT) compared with MLT monotherapy in participants with visual impairment due to centre-involving diabetic macular oedema (DMO).

METHODS

80 patients with best corrected visual acuity (BCVA) between 54 and 78 ETDRS letters due to centre-involving DMO were randomised to combination therapy with Ozurdex and MLT or MLT only. The combination arm received mandated Ozurdex injections at baseline and 16 weeks followed by retreatment criteria-guided pro-re-nata therapy at 32 and 48 weeks. Patients randomised to MLT only were treated every 16 weeks if clinically significant macular oedema was present. The primary outcome was the mean change from baseline in BCVA between arms at 56 weeks.

RESULTS

The mean change in BCVA at 56 weeks was -0.3 (SD 11.4) ETDRS letters in the combination arm versus +0.4 (SD 9.6) ETDRS (Early Treatment Diabetic Retinopathy study) letters in the MLT arm (effect estimate 1.15 (95% CI -3.32 to 5.61)). However, at 56 weeks, a post hoc comparison of central subfield thickness (CST) showed a decrease of -113 μm (IQR -218, -64) (combination) versus -17 μm (-128, 12) (MLT arm) (p<0.001). Elevated intraocular pressure requiring topical therapy was observed in 8 (20%) eyes in the combination versus 1 (2.5%) in the MLT arm. 33% (9/27) of phakic patients in the combination arm underwent cataract surgery.

CONCLUSIONS

Visual outcome following combination therapy did not differ from MLT alone in the centre-involving DMO despite a significant decrease in CST likely due to an entry visual acuity-related ceiling effect and cataract development.

TRIAL REGISTRATION NUMBER

EudraCT 2011-003339-74.

Intravitreal Dexamethasone Implant for Treatment of Refractory Behçet Posterior Uveitis: One-year Follow-up Results

PURPOSE

To investigate the results of dexamethasone (DEX) implant in the treatment of eyes with refractory Behçet posterior uveitis.

METHODS

A total of 17 eyes of 12 patients with active Behçet posterior uveitis were enrolled in the study. A single intravitreal injection of DEX implant was applied to each eye. Best corrected visual acuity (BCVA), central macular thickness (CMT), vitreous haze score, and intraocular pressure (IOP) were determined, at baseline and control visits of months 1, 3, 6, and 12.

RESULTS

The mean BCVA was significantly increased from baseline at each control visit (all p < 0.05). The mean CMT and vitreous haze score were significantly decreased from baseline at each control visit (all p < 0.05). Three eyes showed IOP spikes requiring topical anti-glaucomatous treatment.

CONCLUSIONS

A single injection of DEX implant was safe and effective, as an additional treatment to systemic immunomodulatory drugs, in the treatment of refractory Behçet posterior uveitis, for a 6-month period.

Twelve-Month Results of a Single or Multiple Dexamethasone Intravitreal Implant for Macular Edema following Uncomplicated Phacoemulsification

The clinical efficacy of one or two intravitreal injections of a continued deliverance dexamethasone 700 μg implant in ten patients with persistent macular edema following uncomplicated phacoemulsification was evaluated. Complete ophthalmological examination and spectral domain optical coherence tomography were carried out. Follow-up was at day 7 and months 1, 2, 4, 6, 8, and 12. At baseline mean best corrected visual acuity was 62 Early Treatment Diabetic Retinopathy Study Chart letters, which showed statistically significant improvement at each follow-up, except at month 6, to reach 79 letters at month 12 (P = 0.018). Prior to treatment mean central foveal thickness was 622 μm, which showed statistically significant improvement at each follow-up to reach a mean value of 282 μm (P = 0.012) at month 12. Five patients received a second dexamethasone implant at month 7. Two patients were excluded from the study at months 4 and 8. Intraocular pressure remained stable during the study period with the exception of mild increase in two patients requiring topical therapy. In conclusion there was statistically significant improvement of best corrected visual acuity and mean central foveal thickness with one or two intravitreal dexamethasone implants over 12 months.

Efficacy of Dexamethasone Intravitreal Implant for the Treatment of Diabetic Macular Edema

Purpose

To assess the efficacy of a single dexamethasone intravitreal implant (Dex-I) injection for the treatment of diabetic macular edema (DME).

Methods

This was a retrospective chart review of 39 eyes (34 consecutive patients). Best-corrected visual acuity (BCVA), central macular thickness (CMT), and increase in intraocular pressure (IOP) (>24 mm Hg) were analyzed before treatment and 2 and 4 months after injection.

Results

Preoperative mean CMT was 559 ± 111 μm and decreased to 338 ± 84 and 477 ± 140 μm 2 and 4 months after injection, respectively. Although all eyes showed a significant decrease in CMT 2 months after injection (p<0.0001), a recurrence of the macular edema was observed 4 months after injection in 79% of eyes. Mean BCVA improvement (logMAR) was 0.13 ± 0.18 (p<0.0001) and 0.07 ± 0.21 (p = 0.049) 2 and 4 months after injection, respectively, without significant difference between vitrectomized and nonvitrectomized eyes. Eight eyes (21%) developed reversible increase in IOP 2 months after injection.

Conclusions

Thirty percent of DME eyes had gained more than 2 logMAR lines 2 months after Dex-I injection and safety was good. Visual acuity gain was maintained 4 months after injection despite a recurrence of edema in most cases.

Novel Therapies in Development for Diabetic Macular Edema

Diabetic macular edema (DME) secondary to diabetic retinopathy (DR) is a major cause for functional visual loss in the developed world. Laser photocoagulation has been used for decades in the treatment of DME. However, the advent of anti-vascular endothelial growth factor (anti-VEGF) has revolutionized the treatment of DME. Three important anti-VEGF agents whose efficacy has been well established via phase III clinical trials include ranibizumab, bevacizumab, and aflibercept. However, even in the era of anti-VEGF therapies, there are some challenges that retina specialists have to confront in managing patients with DME. These include the need for frequent treatment and an unpredictable response to therapy. There is evidence to suggest that pathways other than the VEGF pathway may be playing a role in the development of DME. Thus, extensive research is focused on development of novel agents that target these pathways. This review focuses on novel therapeutic agents in development, which may be used as a monotherapy or in combination with anti-VEGF agents, for the management of DME in the future.

Perspective on the role of Ozurdex (dexamethasone intravitreal implant) in the management of diabetic macular oedema

Diabetic macular oedema (DMO) is the most common cause of visual loss in the working age population. Intravitreal therapy has superseded macular laser as the first-line treatment for the management of centre-involving DMO in most patients. As well as the proven efficacy of intravitreal anti-vascular endothelial growth factor (anti-VEGF) agents, phase II and III clinical trials of Ozurdex intravitreal dexamethasone implants for DMO have also demonstrated a mean increase in visual acuity and corresponding mean reduction in central macular thickness, particularly in pseudophakic eyes. Because of the risk of visual loss from cataract, glaucoma and intraocular infection with the use of intravitreal steroids, Ozurdex tends to be reserved for use in patients unresponsive to anti-VEGF therapy for centre-involving DMO. Situations where Ozurdex may be considered a first-line treatment option for eyes with centre-involving DMO include pseudophakia, impending cataract surgery, or in the context of a recent arterial thromboembolic event. Because of their stable pharmacokinetics, Ozurdex slow-release implants may also be considered in vitrectomized eyes.

New Therapeutic Approaches in Diabetic Retinopathy

Diabetic retinopathy is a common microvascular complication of diabetes mellitus. It affects a substantial proportion of US adults over age 40. The condition is a leading cause of visual loss. Much attention has been given to expanding the role of current treatments along with investigating various novel therapies and drug delivery methods. In the treatment of diabetic macular edema (DME), intravitreal pharmacotherapies, especially anti-vascular endothelial growth factor (anti-VEGF) agents, have gained popularity. Currently, anti-VEGF agents are often used as first-line agents in center-involved DME, with recent data suggesting that among these agents, aflibercept leads to better visual outcomes in patients with worse baseline visual acuities. While photocoagulation remains the standard treatment for proliferative diabetic retinopathy (PDR), recent FDA approvals of ranibizumab and aflibercept in the management of diabetic retinopathy associated with DME may suggest a potential for pharmacologic treatments of PDR as well. Novel therapies, including small interfering RNAs, chemokines, kallikrein-kinin inhibitors, and various anti-angiogenic agents, are currently being evaluated for the management of diabetic retinopathy and DME. In addition to these strategies, novel drug delivery methods such as sustained-release implants and refillable reservoir implants are either under active evaluation or have recently gained FDA approval. This review provides an update on the novel developments in the treatment of diabetic retinopathy.

Comparison of the release profile and pharmacokinetics of intact and fragmented dexamethasone intravitreal implants in rabbit eyes

PURPOSE

Dexamethasone intravitreal implant (DEX implant, Ozurdex(®); Allergan, Inc.) is used to treat noninfectious posterior uveitis and macular edema associated with retinal vein occlusion and diabetic retinopathy. Two recently published reports of DEX implant fragmentation shortly after injection have raised concerns about the potential for faster implant dissolution and elevated ocular dexamethasone concentrations. This study compared the in vivo release profile and pharmacokinetic behavior of intact and fragmented DEX implants.

METHODS

DEX implant was surgically implanted as a single unit or fragmented into 3 pieces in the posterior segment of opposing eyes of 36 New Zealand white rabbits. The release of dexamethasone over time from 1-piece and 3-piece fragmented implants dissolved in solution in vitro was compared with that from the 1-piece and 3-piece fragmented implants placed in the rabbit eyes. In addition, dexamethasone concentrations in the vitreous and aqueous humors of each eye were measured at 3 h and days 1, 7, 14, 21, and 28. High-performance liquid chromatography and liquid chromatography-tandem mass spectrometry were used for assays.

RESULTS

Dexamethasone release from the 1-piece and 3-piece DEX implants in vivo was not different and was consistent with the in vitro release pattern. Moreover, the concentration profile of dexamethasone in the vitreous and aqueous humors was similar for the 1-piece and 3-piece DEX implants at each time point measured.

CONCLUSIONS

DEX implant fragmentation neither accelerated its dissolution nor increased the dexamethasone concentration delivered at a given time. Accordingly, DEX implant fragmentation is unlikely to have clinically significant effects in patients.

Pro-Permeability Factors After Dexamethasone Implant in Retinal Vein Occlusion; the Ozurdex for Retinal Vein Occlusion (ORVO) Study

PURPOSE

To correlate aqueous vasoactive protein changes with macular edema after dexamethasone implant in retinal vein occlusion (RVO).

DESIGN

Prospective, interventional case series.

METHODS

Twenty-three central RVO (CRVO) and 17 branch RVO (BRVO) subjects with edema despite prior anti-vascular endothelial growth factor (VEGF) treatment had aqueous taps at baseline and 4 and 16 weeks after dexamethasone implant. Best-corrected visual acuity (BCVA) and center subfield thickness were measured every 4 weeks. Aqueous vasoactive protein levels were measured by protein array or enzyme-linked immunosorbent assay.

RESULTS

Thirty-two vasoactive proteins were detected in aqueous in untreated eyes with macular edema due to RVO. Reduction in excess foveal thickness after dexamethasone implant correlated with reduction in persephin and pentraxin 3 (Pearson correlation coefficients = 0.682 and 0.638, P = .014 and P = .003). Other protein changes differed among RVO patients as edema decreased, but ≥50% of patients showed reductions in hepatocyte growth factor, endocrine gland VEGF, insulin-like growth factor binding proteins, or endostatin by ≥30%. Enzyme-linked immunosorbent assay in 18 eyes (12 CRVO, 6 BRVO) showed baseline levels of hepatocyte growth factor and VEGF of 168.2 ± 20.1 pg/mL and 78.7 ± 10.0 pg/mL, and each was reduced in 12 eyes after dexamethasone implant.

CONCLUSIONS

Dexamethasone implants reduce several pro-permeability proteins providing a multitargeted approach in RVO. No single protein in addition to VEGF can be implicated as a contributor in all patients. Candidates for contribution to chronic edema in subgroups of patients that deserve further study include persephin, hepatocyte growth factor, and endocrine gland VEGF.

Dexamethasone intravitreal implant in the treatment of diabetic macular edema

Diabetic macular edema (DME) resembles a chronic, low-grade inflammatory reaction, and is characterized by blood–retinal barrier (BRB) breakdown and retinal capillary leakage. Corticosteroids are of therapeutic benefit because of their anti-inflammatory, antiangiogenic, and BRB-stabilizing properties. Delivery modes include periocular and intravitreal (via pars plana) injection. To offset the short intravitreal half-life of corticosteroid solutions (~3 hours) and the need for frequent intravitreal injections, sustained-release intravitreal corticosteroid implants have been developed. Dexamethasone intravitreal implant provides retinal drug delivery for ≤6 months and recently has been approved for use in the treatment of DME. Pooled findings (n=1,048) from two large-scale, randomized Phase III trials indicated that dexamethasone intravitreal implant (0.35 mg and 0.7 mg) administered at ≥6-month intervals produced sustained improvements in best-corrected visual acuity (BCVA) and macular edema. Significantly more patients showed a ≥15-letter gain in BCVA at 3 years with dexamethasone intravitreal implant 0.35 mg and 0.7 mg than with sham injection (18.4% and 22.2% vs 12.0%). Anatomical assessments showed rapid and sustained reductions in macular edema and slowing of retinopathy progression. Phase II study findings suggest that dexamethasone intravitreal implant is effective in focal, cystoid, and diffuse DME, in vitrectomized eyes, and in combination with laser therapy. Ocular complications of dexamethasone intravitreal implant in Phase III trials included cataract-related events (66.0% in phakic patients), intraocular pressure elevation ≥25 mmHg (29.7%), conjunctival hemorrhage (23.5%), vitreous hemorrhage (10.0%), macular fibrosis (8.3%), conjunctival hyperemia (7.2%), eye pain (6.1%), vitreous detachment (5.8%), and dry eye (5.8%); injection-related complications (eg, retinal tear/detachment, vitreous loss, endophthalmitis) were infrequent (<2%). Dexamethasone intravitreal implant offers a viable treatment option for DME, especially in cases that are persistent or treatment (anti-vascular endothelial growth factor/laser) refractory.

Real-world assessment of intravitreal dexamethasone implant (0.7 mg) in patients with macular edema: the CHROME study

Background

The purpose of this study was to evaluate the real-world use, efficacy, and safety of one or more dexamethasone intravitreal implant(s) 0.7 mg (DEX implant) in patients with macular edema (ME).

Methods

This was a retrospective cohort study of patients with ME secondary to retinal disease treated at ten Canadian retina practices, including one uveitis center. Best-corrected visual acuity (BCVA), central retinal thickness (CRT), intraocular pressure (IOP), glaucoma and cataract surgery, and safety data were collected from the medical charts of patients with ≥3 months of follow-up after the initial DEX implant.

Results

One hundred and one patient charts yielded data on 120 study eyes, including diagnoses of diabetic ME (DME) (n=34), retinal vein occlusion (RVO, n=30; branch in 19 and central in 11), and uveitis (n=23). Patients had a mean age of 60.9 years, and 73.3% of the study eyes had ME for a duration of ≥12 months prior to DEX implant injection(s). Baseline mean (± standard error) BCVA was 0.63±0.03 logMAR (20/86 Snellen equivalents) and mean CRT was 474.4±18.2 μm. The mean number of DEX implant injections was 1.7±0.1 in all study eyes; 44.2% of eyes had repeat DEX implant injections (reinjection interval 2.3–4.9 months). The greatest mean peak changes in BCVA lines of vision occurred in study eyes with uveitis (3.3±0.6, P<0.0001), followed by RVO (1.3±0.5, P<0.01) and DME (0.7±0.5, P>0.05). Significant decreases in CRT were observed: −255.6±43.6 μm for uveitis, −190.9±23.5 μm for DME, and −160.7±39.6 μm for RVO (P<0.0001 for all cohorts). IOP increases of ≥10 mmHg occurred in 20.6%, 24.1%, and 22.7% of DME, RVO, and uveitis study eyes, respectively. IOP-lowering medication was initiated in 29.4%, 16.7%, and 8.7% of DME, RVO, and uveitis study eyes, respectively. Glaucoma surgery was performed in 1.7% of all study eyes and cataract surgery in 29.8% of all phakic study eyes receiving DEX implant(s).

Conclusion

DEX implant(s) alone or combined with other treatments and/or procedures resulted in functional and anatomic improvements in long-standing ME associated with retinal disease.

Diabetic Macular Edema: Pathophysiology and Novel Therapeutic Targets

Diabetic macular edema (DME) is the major cause of vision loss in diabetic persons. Alteration of the blood-retinal barrier is the hallmark of this disease, characterized by pericyte loss and endothelial cell-cell junction breakdown. Recent animal and clinical studies strongly indicate that DME is an inflammatory disease. Multiple cytokines and chemokines are involved in the pathogenesis of DME, with multiple cellular involvement affecting the neurovascular unit. With the introduction of anti-vascular endothelial growth factor (VEGF) agents, the treatment of DME has been revolutionized, and the indication for laser therapy has been limited. However, the response to anti-VEGF drugs in DME is not as robust as in proliferative diabetic retinopathy, and many patients with DME do not show complete resolution of fluid despite multiple intravitreal injections. Potential novel therapies targeting molecules other than VEGF and using new drug-delivery systems currently are being developed and evaluated in clinical trials.

Long-term outcomes of phakic patients with diabetic macular oedema treated with intravitreal fluocinolone acetonide (FAc) implants

PURPOSE

Diabetic macular oedema (DMO) is a leading cause of blindness in working-age adults. Slow-release, nonbioerodible fluocinolone acetonide (FAc) implants have shown efficacy in the treatment of DMO; however, the National Institute for Health and Care Excellence recommends that FAc should be used in patients with chronic DMO considered insufficiently responsive to other available therapies only if the eye to be treated is pseudophakic. The goal of this analysis was to examine treatment outcomes in phakic patients who received 0.2 μg/day FAc implant.

METHODS

This analysis of the phase 3 FAME (Fluocinolone Acetonide in Diabetic Macular Edema) data examines the safety and efficacy of FAc implants in patients who underwent cataract extraction before (cataract before implant (CBI) group) or after (cataract after implant (CAI) group) receiving the implant. The data were further examined by DMO duration.

RESULTS

Best corrected visual acuity (BCVA) after 36 months was comparable in the CAI and CBI groups. Both the percentage of patients gaining ≥ 3 lines of vision and mean change in BCVA letter score were numerically greater in the CAI group. In addition, most patients who underwent cataract surgery experienced a net gain in BCVA from presurgery baseline as well as from original study baseline.

CONCLUSIONS

These data support the use of 0.2 μg/day FAc implants in phakic as well as in pseudophakic patients. These findings will serve as a pilot for design of future studies to evaluate the potential protective effect of FAc implants before cataract surgery in patients with DMO and cataract.

A review of therapies for diabetic macular oedema and rationale for combination therapy

Diabetic macular oedema (DMO) is responsible for significant visual impairment in diabetic patients. The primary cause of DMO is fluid leakage resulting from increased vascular permeability through contributory anatomical and biochemical changes. These include endothelial cell (EC) death or dysfunction, pericyte loss or dysfunction, thickened basement membrane, loss or dysfunction of glial cells, and loss/change of EC Glycocalyx. The molecular changes include increased reactive oxygen species, pro-inflammatory changes: advanced glycation end products, intracellular adhesion molecule-1, Complement 5-9 deposition and cytokines, which result in increased paracellular permeability, tight junction disruption, and increased transcellular permeability. Laser photocoagulation has been the mainstay of treatment until recently when pharmacological treatments were introduced. The current treatments for DMO target reducing vascular leak in the macula once it has occurred, they do not attempt to treat the underlying pathology. These pharmacological treatments are aimed at antagonising vascular endothelial growth factor (VEGF) or non-VEGF inflammatory pathways, and include intravitreal injections of anti-VEGFs (ranibizumab, aflibercept or bevacizumab) or steroids (fluocinolone, dexamethasone or triamcinolone) as single therapies. The available evidence suggests that each individual treatment modality in DMO does not result in a completely dry macula in most cases. The ideal treatment for DMO should improve vision and improve morphological changes in the macular (eg, reduce macular oedema) for a significant duration, reduced adverse events, reduced treatment burden and costs, and be well tolerated by patients. This review evaluates the individual treatments available as monotherapies, and discusses the rationale and potential for combination therapy in DMO. A comprehensive review of clinical trials related to DMO and their outcomes was completed. Where phase III randomised control trials were available, these were referenced, if not available, phase II trials have been included.

[Ocular hypertension after intravitreal steroid injections: Clinical update as of 2015]

Intravitreal injections are a therapeutic delivery method best suited to the treatment of retinal diseases. Recent years have been marked by the use of anti-VEGF agents as well as the arrival of sustained-release corticosteroid implants in France, replacing triamcinolone acetonide. A common complication of IVT steroids is secondary ocular hypertension (OHT) resulting from increased outflow resistance. This article summarizes current understanding. OHT induced by topical steroids has been described for 60 years. Intravitreal use also shows a temporary effect if the exposure is short, dose dependence, and varying incidence depending on the drug used. Sustained release formulations and discontinuing treatment have reduced the risk of induced OHT. Risk factors that induce OHT must be clearly identified prior to an injection. Most cases of OHT can be controlled medically, although differences exist between different drugs. In cases where it cannot be controlled, removal of the implant, selective laser trabeculoplasty, and filtration surgery can be discussed.

Dexamethasone Intravitreal Implant as Adjunctive Therapy to Ranibizumab in Neovascular Age-Related Macular Degeneration: A Multicenter Randomized Controlled Trial

Purpose: To evaluate the efficacy and safety of dexamethasone intravitreal implant 0.7 mg (DEX) as adjunctive therapy to ranibizumab in neovascular age-related macular degeneration (nvAMD). Procedures: This was a 6-month, single-masked, multicenter study. Patients were randomized to DEX implant (n = 123) or sham procedure (n = 120) and received 2 protocol-mandated intravitreal ranibizumab injections. The main outcome measure was injection-free interval to first as-needed ranibizumab injection. Results: DEX increased the injection-free interval versus sham (50th percentile, 34 vs. 29 days; 75th percentile, 85 vs. 56 days; p = 0.016). 8.3% of DEX versus 2.5% of sham-treated patients did not require rescue ranibizumab (p = 0.048). Visual acuity and retinal thickness outcomes were similar in DEX and sham-treated patients. Only reports of conjunctival hemorrhage (18.2 vs. 8.5%) and intraocular pressure elevation (13.2 vs. 4.2%) were significantly different in the DEX versus the sham treatment groups. Conclusion: DEX reduced the need for adjunctive ranibizumab treatment and showed acceptable tolerability in nvAMD patients.

Optimal Treatment of Retinal Vein Occlusion: Canadian Expert Consensus

Background: The availability of new therapeutic approaches, particularly intravitreal anti-vascular endothelial growth factor (anti-VEGF) therapies, has prompted significant changes to the established treatment paradigms for retinal vein occlusion (RVO). Better visual outcomes and significantly lower rates of adverse events have been noted in multiple large randomized clinical trials and have led to a new standard of care for this sight-threatening condition. Objective: To develop an expert consensus for the management of RVO and associated complications in the context of recent clinical evidence. Methods: The development of a Canadian expert consensus for optimal treatment began with a review of clinical evidence, daily practice, and existing treatment guidelines and algorithms. The expert clinicians (11 Canadian retina specialists) met on February 1, 2014, in Toronto to discuss their findings and to propose strategies for consensus. Results: The result of this expert panel is a consensus proposal for Canadian ophthalmologists and retina specialists treating patients presenting with RVO. Treatment algorithms specific to branch and central RVO (BRVO and CRVO) were also developed. Conclusions: The consensus provides guidelines to aid clinicians in managing RVO and associated complications in their daily practice. In summary, laser remains the therapy of choice when neovascularization secondary to RVO is detected. Adjunctive anti-VEGF could be considered in managing neovascularization secondary to RVO in cases of vitreous hemorrhage. Intravitreal anti-VEGF should be considered for symptomatic visual loss associated with center-involving macular edema on optical coherence tomography. Patients with BRVO and a suboptimal response to anti-VEGF could be treated with grid laser, and those with CRVO and an inadequate response to anti-VEGF may be candidates for intravitreal steroids.

Current intravitreal pharmacologic therapies for diabetic macular edema

INTRODUCTION

Diabetic retinopathy is the leading cause of vision loss in working-age adults; it is a highly prevalent cause of vision loss overall and has a potent impact on the quality of life in those with diabetes mellitus and public health in general. Diabetic macular edema (DME) is the most common cause of vision loss from diabetic retinopathy. In patients with diabetes mellitus, chronic hyperglycemia leads to activation of the inflammatory cascade and retinal capillary damage that result in microaneurysm formation in the retina. In addition to the possibility of associated ischemia, microaneurysms are hyperpermeable; the resultant loss of the blood-retinal barrier leads to vision loss if consequent edema involves the center of the fovea. The standard of DME therapy for >25 years was focal laser photocoagulation applied to or near the microaneurysms. However, results from clinical trials of intravitreal vascular endothelial growth factor (VEGF) blockers and corticosteroids for the treatment of DME have led to a dramatic paradigm shift away from laser therapy to primary treatment with these pharmacologic agents.

METHODS

Medline literature search of approaches for treating DME.

RESULTS

Intravitreal pharmacologic treatments with anti-VEGF agents and corticosteroids have recently been shown to be superior to laser treatment of DME.

CONCLUSION

The existence of pharmacologic treatment of DME, shown to be superior to laser monotherapy, has created a seismic change in the approach of treatment of these patients. This review provides a summary of the therapies and the rationale regarding the current pharmacologic therapy of DME.

Advances in drug delivery to the posterior segment

PURPOSE OF REVIEW

Emerging developments and research for drug delivery to the posterior segment offer a promising future for the treatment of vitreoretinal disease. As new technologies enter the market, clinicians should be aware of new indications and ongoing clinical trials.

RECENT FINDINGS

This review summarizes the advantages and shortcomings of the most commonly used drug delivery methods, including vitreous dynamics, physician sustainability and patient preferences. Currently available, intravitreal, corticosteroid-release devices offer surgical and in-office management of retinal vascular disease and posterior uveitis. The suprachoroidal space offers a new anatomic location for the delivery of lower dose medications directly to the target tissue. Implantable drug reservoirs would potentially allow for less frequent intravitreal injections reducing treatment burdens and associated risks. Newer innovations in encapsulated cell technology offer promising results in early clinical trials.

SUMMARY

Although pars plana intravitreal injection remains the mainstay of therapy for many vitreoretinal diseases, targeted delivery and implantable eluting devices are rapidly demonstrating safety and efficacy. These therapeutic modalities offer promising options for the vitreoretinal therapeutic landscape.