Effectiveness of 190 µg Fluocinolone Acetonide and 700 µg Dexamethasone Intravitreal Implants in Diabetic Macular Edema Using the Area-Under-the-Curve Method: The CONSTANT Analysis

The Treatment of Diabetic Retinal Edema with Intravitreal Steroids: How and When

Diabetic macular edema (DME) is a common complication of diabetes mellitus and a leading cause of visual impairment worldwide. It is defined as the diabetes-related accumulation of fluid, proteins, and lipids, with retinal thickening, within the macular area. DME affects a significant proportion of individuals with diabetes, with the prevalence increasing with disease duration and severity. It is estimated that approximately 25-30% of diabetic patients will develop DME during their lifetime. Poor glycemic control, hypertension, hyperlipidemia, diabetes duration, and genetic predisposition are recognized as risk factors for the development and progression of DME. Although the exact pathophysiology is still not completely understood, it has been demonstrated that chronic hyperglycemia triggers a cascade of biochemical processes, including increased oxidative stress, inflammation, activation of vascular endothelial growth factor (VEGF), cellular dysfunction, and apoptosis, with breakdown of the blood-retinal barriers and fluid accumulation within the macular area. Early diagnosis and appropriate management of DME are crucial for improving visual outcomes. Although the control of systemic risk factors still remains the most important strategy in DME treatment, intravitreal pharmacotherapy with anti-VEGF molecules or steroids is currently considered the first-line approach in DME patients, whereas macular laser photocoagulation and pars plana vitrectomy may be useful in selected cases. Available intravitreal steroids, including triamcinolone acetonide injections and dexamethasone and fluocinolone acetonide implants, exert their therapeutic effect by reducing inflammation, inhibiting VEGF expression, stabilizing the blood-retinal barrier and thus reducing vascular permeability. They have been demonstrated to be effective in reducing macular edema and improving visual outcomes in DME patients but are associated with a high risk of intraocular pressure elevation and cataract development, so their use requires an accurate patient selection. This manuscript aims to provide a comprehensive overview of the pathology, epidemiology, risk factors, physiopathology, clinical features, treatment mechanisms of actions, treatment options, prognosis, and ongoing clinical studies related to the treatment of DME, with particular consideration of intravitreal steroids therapy.

DEXTENZA versus Topical Steroid or Antihistamine Therapy for Treatment of Allergic Conjunctivitis

Purpose

To compare clinical outcomes and patient preference for the dexamethasone intracanalicular insert (DEX) versus topical loteprednol (LOT) or olopatadine (OLO) for the treatment of allergic conjunctivitis in a real-world model of allergen exposure.

Methods

This was a prospective comparative trial. Adults with testing-confirmed bilateral allergic conjunctivitis received DEX in the more symptomatic eye and either LOT 2 times daily or OLO once daily for 30 days in the fellow eye. The primary outcome was patient preference for treatment. Clinical outcomes included ocular itching and hyperemia, lid swelling, and watering/tearing. Safety outcomes included intraocular pressure (IOP).

Results

Thirty patients participated and completed the study. All received DEX in the eye with worse symptoms and 15 received LOT and the other 15 received OLO in the other eye. Patients preferred DEX (10/15; 66.7%) over LOT (4/15; 26.7%), with one patient having no preference (p = 0.0103). Patients had no preference between DEX (8/15; 53.3%) and OLO (6/15; 40%), with one patient having no preference (p = 0.1044). In the DEX/LOT cohort, ocular itching and hyperemia improved more with DEX than LOT (p ≤ 0.009), while in the DEX/OLO cohort, the DEX eyes showed greater improvement in conjunctival hyperemia (p < 0.0001) but not itching (p = 0.074). No between-group differences were seen in eyelid swelling or tearing/watering in either cohort. Mean change in IOP was similar between the DEX and LOT eyes (p = 0.4921), and mean IOP rose more in the DEX eyes than the OLO eyes (by <1 mmHg; p = 0.0403).

Conclusion

Overall, this real-world study demonstrated that the dexamethasone intracanalicular insert was as effective as a topical antihistamine/mast cell stabilizer and more effective than topical steroids in relieving the signs and symptoms of allergic conjunctivitis. This insert should be considered as an alternative to topical therapy for the treatment of allergic conjunctivitis.

Functional and Morphological Responses to Fluocinolone Acetonide 0.19 mg in Noninfectious Uveitic Macular Edema Evaluated as the Area-Under-the-Curve

Purpose: This study investigated the impact of baseline clinical and optical coherence tomography (OCT) factors on the response to a 0.19-mg fluocinolone acetonide (FAc) implant in patients with noninfectious uveitic macular edema evaluated by the area under the curve over 24 months. Methods: A retrospective study was conducted of eyes of patients with noninfectious uveitic macular edema undergoing FAc treatment, with follow-up from baseline to 24 months. The area under the curve (AUC) of best-corrected visual acuity (BCVA) and the central macular thickness (CMT) were calculated using the trapezoidal rule. Clinical and OCT data at the time of FAc administration were collected, and associations with AUC of BCVA and CMT changes were investigated. Results: Twenty-three patients were enrolled. BCVA and CMT significantly improved after FAc implantation (P < 0.05). AUCBCVA and AUCCMT were 0.41 ± 0.33 logarithm of minimal angle of resolution/6 months and 320.15 ± 321.64 μm/6 months, respectively. Better baseline BCVA (coefficient [coef.] = 0.83, P < 0.001) and macular thickness reduction after FAc administration (coef. = -0.0001, P < 0.05) were associated with better BCVA after FAc treatment. In contrast, baseline OCT biomarkers such as ellipsoid zone reflectivity and choroidal vascularity index, sex, or disease duration before FAc injection showed no correlation with AUCBCVA and AUCCMT (P > 0.05). The younger the patient at the time of FAc injection, the greater the reduction in CMT (coef. = 1.76, P < 0.05). Conclusions: Among all clinical and morphological baseline factors, Baseline BCVA was the strongest predictor for AUCBCVA, while no association with baseline OCT features was observed. Overall, improvement of BCVA and CMT after FAc injection was maintained over 24 months. This study is registered in the German Clinical Trials Register under the DRKS-ID: DRKS00024399.

Factors associated with the response to fluocinolone acetonide 0.19 mg in diabetic macular oedema evaluated as the area-under-the-curve

OBJECTIVES

The area-under-the-curve (AUC) measures the average drug effect over time. We investigated the impact of baseline clinical and optical coherence tomography (OCT) factors on the response to fluocinolone acetonide (FAc) 0.19 mg implant in patients with diabetic macular oedema (DMO) as the AUC over 36 months.

METHODS

Retrospective study of DMO eyes undergoing FAc with follow-up from 12 to 36 months. The AUC of the best-corrected visual acuity (BCVA) and the central macular thickness (CMT) were calculated with the trapezoidal rule. Demographic and clinical data at the time of FAc administration were collected, and associations with BCVA and CMT changes were investigated with linear mixed models.

RESULTS

Eighty-nine eyes of 63 patients were enroled; median follow-up was 26 months. Mean±standard deviation (SD) AUCBCVA and AUCCMT after FAc injection were 0.24 ± 0.17 LogMAR/month and 179.6 ± 54.3 μm/month, respectively. Worse baseline BCVA (β = 0.30 LogMAR/month, p < 0.001), higher AUCCMT after FAc administration (β = 0.08 LogMAR/month, p < 0.001), diagnosis of type 1 diabetes (β = -0.04 LogMAR/month, p = 0.04), and absent ELM/EZ layers (β = 0.06 LogMAR/month, p = 0.01) were associated with worse vision over time (higher AUCBCVA). Eyes with higher CMT at baseline (β = 9.61 μm/month, p < 0.001) and those with tractional DMO (β = 24.7 μm/month, p = 0.01) had worse anatomic outcomes (higher AUCCMT). The need for additional treatments after FAc was also associated with higher AUCCMT (β = 33.9 μm/month, p = 0.001).

CONCLUSION

Baseline better visual acuity, lower macular thickness, and photoreceptors' layers integrity are associated with better functional response to FAc in DMO. Eyes with severe DMO at the time of implant or tractional oedema have worse anatomic response. These findings might guide clinicians in a more informed decisional algorithm in treating DMO.

Fluocinolone acetonide implant in diabetic macular edema: International experts' panel consensus guidelines and treatment algorithm

Center-involving diabetic macular edema (DME) is a leading cause of vision impairment in working-age adults. While its management is particularly challenging in a poorly compliant population, continuous innovation and the advent of new molecules have improved its outcome. The control of glycemia and of systemic aggravating factors remain essential to slow down progression of disease complications including DME. The indications for macular laser photocoagulation has progressively been phased out as a standard of care and replaced by local intraocular anti-VEGFs biologics and glucocorticoids (GCs). Intravitreal GCs in controlled-release drug delivery systems have allowed to reduce injection frequency and treatment burden. The non biodegradable Fluocinolone Acetonide (FAc) implant allows a long-lasting stabilization of both functional and anatomic improvements. However, adequate patient selection and monitoring through regular follow-up are essential for optimal results. Based on their experience and the latest literature, the aim of the present review is to provide international expert panel consensus on the place of the FAc implant in the treatment algorithm of DME, as well as its safety profile and how to manage it.

Efficacy of 0.19 mg Fluocinolone Acetonide Implant in Non-infectious Posterior Uveitis Evaluated as Area Under the Curve

Introduction

This study reports the outcomes of fluocinolone acetonide intravitreal implant (FAc, Iluvien^®, SIFI, Italy) in patients affected by macular edema secondary to chronic non-infectious uveitis of the posterior segment (NIU-PS).

Methods

This was a retrospective study of patients with NIU-PS and macular thickening undergoing FAc implant at San Raffaele Hospital (Milan, Italy). Clinical data, including best-corrected visual acuity (BCVA), intraocular pressure (IOP), and central macular thickness (CMT), were collected at the time of FAc administration (baseline) and at 1, 6, and 12 months. The area under the curve (AUC) of the BCVA (AUC_BCVA) and CMT (AUC_CMT) was correlated with baseline factors; β estimates and 95% confidence interval (CI) are provided.

Results

Ten eyes of seven patients (60 ± 12 years; 4 male, 57%) were included. The BCVA significantly improved from month 6 (p = 0.03). The CMT improved from month 1 and was persistently lower than baseline until month 12 (p < 0.001). The AUC_BCVA correlated with baseline BCVA (β = 2.5 logMAR; 95% CI 1.59–3.41; p < 0.001), while the mean AUC_CMT positively correlated with the baseline CMT (β = 2.1 μm; 95% CI 0.41–3.80; p = 0.02). No adverse events were recorded over 1 year.

Conclusions

Better visual acuity at the time of FAc administration was associated with better visual function after FAc. Less severe macular edema correlated with better anatomic response. The FAc implant was a safe option for resolving macular edema secondary to NIU-PS.

Recent trends in drug-delivery systems for the treatment of diabetic retinopathy and associated fibrosis

Diabetic retinopathy is a frequent microvascular complication of diabetes and a major cause of visual impairment. In advanced stages, the abnormal neovascularization can lead to fibrosis and subsequent tractional retinal detachment and blindness. The low bioavailability of the drugs at the target site imposed by the anatomic and physiologic barriers within the eye, requires long term treatments with frequent injections that often compromise patient's compliance and increase the risk of developing more complications. In recent years, much effort has been put towards the development of new drug delivery platforms aiming to enhance their permeation, to prolong their retention time at the target site and to provide a sustained release with reduced toxicity and improved efficacy. This review provides an overview of the etiology and pathophysiology of diabetic retinopathy and current treatments. It addresses the specific challenges associated to the different ocular delivery routes and provides a critical review of the most recent developments made in the drug delivery field.

Switching to intravitreal fluocinolone acetonide implant for refractory diabetic macular edema: 12- and 24-month results

PURPOSE

To report visual and anatomical outcomes of chronic/refractory diabetic macular edema (DME) treated with intravitreal fluocinolone acetonide implant.

SETTING

Retrospective, one arm, multicentric study.

METHOD

Between 2013 and 2018, 27 consecutive eyes of 25 patients with chronic/refractory DME were treated with a fluocinolone acetonide intravitreal implant. Best registered visual acuity (BRVA), central retinal thickness (CRT), and Goldmann tonometry intraocular pressure (IOP) were assessed at 12 and 24 months. The need for IOP lowering treatment as well as top-up therapy during the follow-up were also assessed.

RESULTS

The duration of DME prior to treatment in our study was 54 ± 24 months. The baseline mean BRVA of 0.7 ± 0.34 logMAR improved to 0.5 ± 0.3 (p = 0.01) at 12 months and 0.46 ± 0.3 (p = 0.04) at 24 months. At 12 months, BRVA improved in 14 eyes (52%), stabilized in 5 eyes (20%), and decreased in 3 eyes (11%). At 24 months, BRVA improved further in 6 eyes (24%), stabilized in 3 eyes (12%), and decreased in 6 eyes (24 %). Mean CRT decreased from 497 ± 176 to 349 ± 186 μm at 12 months (p = 0.0005) and to 267 ± 104 μm at 24 months (p = 0.001). Only five eyes required additional treatment for DME and only three eyes required treatment for raised IOP.

DISCUSSION

Our results show that the visual and the anatomical improvements achieved by a single injection of a fluocinolone acetonide implant were maintained up to 24 months with minimal additional therapy even in eyes with a long and heavy history; however, IOP monitoring remains essential.

Differential response to intravitreal dexamethasone implant in naïve and previously treated diabetic macular edema eyes

Background

To identify different response patterns to intravitreal dexamethasone implants (IDI) in naïve and previously treated (PT) diabetic macular edema (DME) eyes in a real-life setting.

Methods

342 IDI injections (203 DME eyes) were included. Number of IDI injections, percentage (%) of eyes with 1, 2, 3 and ≥ 4 injections, time to reinjections, visual acuity (VA), intraocular pressure (IOP) and central retinal thickness (CRT) were evaluated for naïve and PT DME eyes over 24 months.

Results

Mean number of injections was significantly lower in naïve vs PT DME eyes (1.40 ± 0.9 vs 1.82 ± 0.9, p < 0.001). The percentage of eyes receiving 1 injection was significantly higher in naïve vs PT DME eyes (76.1 vs 47.7), (p < 0.001). However, it was significantly lower for 2 (16.4 vs 29.4), or 3 injections (1.4 vs 17.6) (both p < 0.001), with no differences in eyes receiving ≥4 injections (5.9 vs 5.1 respectively, p = 0.80). Mean time to reinjection was not significantly different between both groups for the second, third and fourth injection (9.6 ± 4.0 vs 10.0 ± 5.5, p = 0.75, 13.2 ± 4.0 vs 16.0 ± 3.5, p = 0.21 and 21.7 ± 3.8 vs 19.7 ± 5.8, p = 0.55). VA scores were consistently better in naïve vs PT DME eyes at all studied timepoints, with no significant differences in CRT reduction or adverse effect rates.

Conclusion

Naïve DME eyes received lower number of IDI injections and showed better VA levels than PT DME eyes for 24 months in a real-world setting. This data supports the IDI use in early DME stages and provide further evidence of better IDI response when used as first-line therapy.