Ozurdex (dexamethasone intravitreal implant) for the treatment of intermediate, posterior, and panuveitis: a systematic review of the current evidence

Clinical prediction nomogram for steroid-induced ocular hypertension risk in patients with intravitreal dexamethasone implant

Background

Recognizing the risk factors and understanding the mechanisms underlying steroid-induced ocular hypertension (SIOH) are vital to prevent potent vision loss and ensure the safety and effectiveness of dexamethasone (DEX) injections. The study aimed to develop a novel nomogram for predicting the risk of SIOH and determining safety zones for steroid injections.

Methods

This single-center, retrospective, case-control study included a total of 154 eyes with available measured axial length that had undergone AS-OCT and DEX implantation at the Yonsei University Health System. The eyes were categorized into the SIOH (n = 39) and post-steroid normal IOP (n = 115) groups. We measured intraocular pressure (IOP) for all eyes prior to DEX implantation, at 1 week post-implantation, and at 1, 2, 3, 6, and 12 months thereafter. We used AS-OCT to analyze the trabecular meshwork (TM) height and ocular parameters.

Results

The predictive nomogram, including TM height, yielded an AUC of 0.807 (95 % confidence interval [CI], 0.737-0.877) and demonstrated significantly higher predictive accuracy than that of previous nomograms, which did not consider TM height and had an AUC of 0.644 (95 % CI, 0.543-0.745) (p = 0.031). The calibration plot demonstrated a strong predictive accuracy for a predicted value of approximately 0.4. We established cutoff values to ensure different levels of sensitivity and specificity within the safety zone following DEX implantation.

Conclusion

Our improved nomogram incorporating TM height as a newly identified risk factor, established a safety threshold for intravitreal DEX implantation, helping identify safe individuals from those who require caution.

Diabetic macular edema: Upcoming therapies

Diabetic macular edema (DME) is a serious vision-threatening complication that can arise at any stage of diabetic retinopathy. Primary treatment involves anti-vascular endothelial growth factor (VEGF) agents, which are highly effective but associated with challenges, such as the need for frequent injections, relapses, and resistance to therapy. Therefore, there has been a growing interest in developing new treatments that offer similar or superior outcomes in DME. This review article explores emerging treatments, including WNT agonists, gene therapy, protein inhibitors, and, most importantly, the first-ever non-invasive and oral drugs. The evolving therapies in diabetic retinopathy offer hope for continued improvement in vision loss associated with one of the most common chronic conditions worldwide.

Improving corneal permeability of dexamethasone using penetration enhancing agents: First step towards achieving topical drug delivery to the retina

With an ever-increasing burden of vision loss caused by diseases of the posterior ocular segment, there is an unmet clinical need for non-invasive treatment strategies. Topical drug application using eye drops suffers from low to negligible bioavailability to the posterior segment as a result of static and dynamic defensive ocular barriers to penetration, while invasive delivery systems are expensive to administer and suffer potentially severe complications. As the cornea is the main anatomical barrier to uptake of topically applied drugs from the ocular surface, we present an approach to increase corneal permeability of a corticosteroid, dexamethasone sodium-phosphate (DSP), using a novel penetration enhancing agent (PEA). We synthesised a novel polyacetylene (pAc) polymer and compared its activity to two previously described cell penetrating peptide (CPP) based PEAs, TAT and penetratin, with respect to increasing transcorneal permeability of DSP in a rapid ex-vivo porcine corneal assay over 60 min. The transcorneal apparent permeability coefficients (Papp) for diffusion of pAc, and fluorescein isothiocyanate (FITC) conjugated TAT and penetratin were up to 5 times higher (p < 0.001), when compared to controls. When pAc was used in formulation with DSP, an almost 5-fold significant increase was observed in Papp of DSP across the cornea (p = 0.0130), a significant 6-fold increase with TAT (p = 0.0377), and almost 7-fold mean increase with penetratin (p = 0.9540). Furthermore, we investigated whether the PEAs caused any irreversible damage to the barrier integrity of the corneal epithelium by measuring transepithelial electrical resistance (TEER) and immunostaining of tight junction proteins using zonula occludens-1 (ZO-1) and occludin antibodies. There was no damage or structural toxicity, and the barrier integrity was preserved after PEA application. Finally, an in-vitro cytotoxicity assessment of all PEAs in human retinal pigment epithelium cells (ARPE-19) demonstrated that all PEAs were very well-tolerated, with IC50 values of 64.79 mM for pAc and 1335.45 µM and 87.26 µM for TAT and penetratin, respectively. Our results suggest that this drug delivery technology could potentially be used to achieve a significantly higher intraocular therapeutic bioavailability after topical eye drop administration, than currently afforded.

Intravitreal implants manufactured by supercritical foaming for treating retinal diseases

Chronic retinal diseases, such as age-related macular degeneration (AMD), are a major cause of global visual impairment. However, current treatment methods involving repetitive intravitreal injections pose financial and health burdens for patients. The development of controlled drug release systems, particularly for biological drugs, is still an unmet need in prolonging drug release within the vitreous chamber. To address this, green supercritical carbon dioxide (scCO2) foaming technology was employed to manufacture porous poly(lactic-co-glycolic acid) (PLGA)-based intravitreal implants loaded with dexamethasone. The desired implant dimensions were achieved through 3D printing of customised moulds. By varying the depressurisation rates during the foaming process, implants with different porosities and dexamethasone release rates were successfully obtained. These implants demonstrated controlled drug release for up to four months, surpassing the performance of previously developed implants. In view of the positive results obtained, a pilot study was conducted using the monoclonal antibody bevacizumab to explore the feasibility of this technology for preparing intraocular implants loaded with biologic drug molecules. Overall, this study presents a greener and more sustainable alternative to conventional implant manufacturing techniques, particularly suited for drugs that are susceptible to degradation under harsh conditions.

Beyond Tissue replacement: The Emerging role of smart implants in healthcare

Smart implants are increasingly used to treat various diseases, track patient status, and restore tissue and organ function. These devices support internal organs, actively stimulate nerves, and monitor essential functions. With continuous monitoring or stimulation, patient observation quality and subsequent treatment can be improved. Additionally, using biodegradable and entirely excreted implant materials eliminates the need for surgical removal, providing a patient-friendly solution. In this review, we classify smart implants and discuss the latest prototypes, materials, and technologies employed in their creation. Our focus lies in exploring medical devices beyond replacing an organ or tissue and incorporating new functionality through sensors and electronic circuits. We also examine the advantages, opportunities, and challenges of creating implantable devices that preserve all critical functions. By presenting an in-depth overview of the current state-of-the-art smart implants, we shed light on persistent issues and limitations while discussing potential avenues for future advancements in materials used for these devices.

The Efficacy and Safety of Intravitreal Dexamethasone Implant as Anti-inflammatory Monotherapy in the Management of Tuberculosis-associated Intermediate Uveitis

AIM

To study the long-term efficacy and safety of Ozurdex as anti-inflammatory monotherapy in the management of tuberculosis-associated intermediate uveitis (TBIU).

METHODS

Retrospective analysis of eyes with TBIU that received Ozurdex as anti-inflammatory monotherapy with a follow-up of at least 1 year.

RESULTS

13 eyes (2 pseudophakic) of 11 patients were included. Mean BCVA improved from 0.65 to 0.11 at 3 months (p = .0005) and remained 0.11 at 1 year. Mean central foveal thickness improved from 452.87µ to 187.25µ at 3 months (p = .0009) and 184.62µ at 1 year in 8 eyes with CME. Mean vitreous haze improved from 2.38 to 0.11 at 3 months with no recurrences at 1 year. Mean IOP increased from 13.15mmHg to 15.53mmHg (p = .013) at 2 months and reduced to 12.46mmHg by 1 year. None required antiglaucoma medication. One eye underwent cataract surgery. The mean follow-up was 18.4 months.

CONCLUSION

Ozurdex is safe and efficacious in TBIU as anti-inflammatory monotherapy in conjunction with antitubercular therapy.

A New Era in Ocular Therapeutics: Advanced Drug Delivery Systems for Uveitis and Neuro-Ophthalmologic Conditions

The eye's intricate anatomical barriers pose significant challenges to the penetration, residence time, and bioavailability of topically applied medications, particularly in managing uveitis and neuro-ophthalmologic conditions. Addressing this issue, polymeric nano-based drug delivery systems (DDS) have surfaced as a promising solution. These systems enhance drug bioavailability in hard-to-reach target tissues, extend residence time within ocular tissues, and utilize biodegradable and nanosized polymers to reduce undesirable side effects. Thus, they have stimulated substantial interest in crafting innovative treatments for uveitis and neuro-ophthalmologic diseases. This review provides a comprehensive exploration of polymeric nano-based DDS used for managing these conditions. We discuss the present therapeutic hurdles posed by these diseases and explore the potential role of various biopolymers in broadening our treatment repertoire. Our study incorporates a detailed literature review of preclinical and clinical studies from 2017 to 2023. Owing to advancements in polymer science, ocular DDS has made rapid strides, showing tremendous potential to revolutionize the treatment of patients with uveitis and neuro-ophthalmologic disorders.

Ocular immunosuppressive microenvironment and novel drug delivery for control of uveitis

Ocular immune privilege is a phenomenon described by Peter Medawar in relation to the indefinite survival of the placement of foreign tissue grafts into the eye. Several mechanisms have been described that contribute to ocular immune privilege, such as a blood-ocular barrier and lack of lymphatics in the eye, the production of immune-suppressing molecules inside the ocular microenvironment, and the induction of systemic regulatory immunity against antigens found in the eye. Because ocular immune privilege is not absolute, failure of it can result in uveitis. Uveitis is a group of inflammatory disorders that can lead to vision loss if not treated properly. The current uveitis treatments involve the use of immunosuppressive and anti-inflammatory medications. Researching mechanisms of ocular immune privilege and the development of novel treatments for uveitis is ongoing. This review discusses mechanisms of ocular immune privilege, followed by an overview of uveitis treatments and ongoing clinical trials.

Treatment of Non-Infectious Posterior Uveitis with Dexamethasone Intravitreal Implants in a Real-World Setting

Purpose

The present study aimed to assess the efficacy and safety associated to the treatment of patients with non-infectious posterior uveitis with intravitreal dexamethasone (DEX) implants in a real-world clinical setting.

Patients and Methods

This is a retrospective, single center analysis of the data from 29 patients with non-infectious posterior uveitis in whom 38 eyes were treated with dexamethasone intravitreal implants in routine clinical practice between January 2012 and October 2017. The parameters of visual acuity (VA), intraocular pressure (IOP) and central retinal thickness (CRT) were recorded 6 weeks after the first implant was administered, in accordance with the clinical guidelines for the use of these implants, and after a 6-month follow-up period. In addition, the formation of cataracts was evaluated at 12 months.

Results

Treatment with the DEX implant caused a significant improvement in the VA from baseline at 6 weeks in eyes treated with 2-6 implants and for eyes without cataracts. A significant decrease in CRT was observed relative to the baseline at 6 weeks for eyes treated with 1 and 2-6 implants, which was maintained at 6 months for those eyes treated with 2-6 implants. This significant improvement in CRT at 6 weeks and 6 months was evident in eyes with and without cataracts. During the study period, the IOP was found to increase significantly from baseline at 6 weeks in some eyes but this was managed topically, and no surgical intervention was necessary.

Conclusion

Intravitreal DEX implants represent an effective and safe therapy for the treatment of non-infectious uveitis in routine clinical practice, producing favorable visual and anatomical outcomes after the administration of just 2-6 DEX implants.

Efficacy and safety of single-dose intravitreal dexamethasone implant in non-infectious uveitic macular edema: A systematic review and meta-analysis

Purpose

We conducted a systematic review and meta-analysis to investigate the efficacy and safety of single-dose intravitreal dexamethasone (DEX) implant for treating non-infectious uveitic macular edema (UME).

Methods

Studies including clinical outcomes of the DEX implant in UME were comprehensively searched in PubMed, Embase, and Cochrane databases for potential studies from inception to July 2022. The primary outcomes were best corrected visual acuity (BCVA) and central macular thickness (CMT) during the follow-up period. Stata 12.0 was used to perform the statistical analyses.

Results

Six retrospective studies and one prospective investigation involving 201 eyes were ultimately included. Significantly improved BCVA was observed from baseline to 1 month (WMD = -0.15, 95%CI = -0.24, -0.06), 3 months (WMD = -0.22, 95%CI = -0.29, -0.15), and 6 months (WMD = -0.24, 95%CI = -0.35, -0.13), after single-dose DEX implant. When considering CMT, macular thickness of 1 month (WMD = -179.77, 95%CI = -223.45, -136.09), 3 months (WMD = -179.13, 95%CI = -232.63, -125.63), and 6 months (WMD = -140.25, 95%CI = -227.61, -52.88) decreased in comparison with baseline, with statistical significance.

Conclusion

Based on the current results, this meta-analysis confirmed favorable visual prognosis and anatomical improvement in patients with UME, after receiving the single-dose DEX implant. The most common adverse event is increased intraocular pressure, which could be controlled with topical medications.Systematic Review Registration:https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022325969.

Efficacy and safety of intravitreal and periocular injection of corticosteroids in non-infectious uveitis: a systematic review

Uveitis is among the leading causes of visual loss in the working age population. In non-infectious uveitis, corticosteroids are the first line therapy. We sought to review systematically the evidence regarding the regional corticosteroid delivery modalities in the treatment of non-infectious uveitis. A five-database search (Pubmed, ISI Web of Science, Cochrane, ClinicalTrials.gov, and Scopus) was performed from inception to February, 2021. Nineteen studies with a total of 1935 eyes of 1753 patients were selected from 8922 abstracts retrieved by the initial search. The most frequently compared regimens were intravitreal triamcinolone acetonide injection and orbital floor triamcinolone acetonide injection (2 studies), intravitreal triamcinolone acetonide injection and posterior sub-Tenon triamcinolone acetonide injection (2 studies), and posterior sub-Tenon triamcinolone acetonide injection with the intravitreal dexamethasone implant (2 studies). Our results show that the intravitreal injection of corticosteroids is more effective, but is associated with more adverse events, than periocular injection. Some evidence supports the use of subconjunctival triamcinolone acetonide over intravitreal/periocular triamcinolone acetonide. Moreover, the overall results of 0.59 mg dosage of the intravitreal fluocinolone acetonide implant were superior to those from the 2.1 mg dose. The evidence, however, is not robust and further studies with standardized outcomes are warranted.

Intravitreal lupeol: A new potential therapeutic strategy for noninfectious uveitis

Lupeol is a pentacyclic triterpene with known anti-inflammatory effects. However, its role in the treatment of noninfectious uveitis has not been explored. This work investigated anti-inflammatory activity of lupeol in ocular tissues with in vitro and in vivo models. First, we evaluated the effect of lupeol (100 µM) on inflammatory response induced by lipopolysaccharide (LPS) in retinal pigment epithelium cells (ARPE-19) by measuring levels of released interleukins (IL-6 and IL-8). Then, we investigated the anti-inflammatory action of intravitreal lupeol in a rodent model of panuveitis induced by Mycobacterium bovis Calmette-Guérin Bacillus (BCG). Rats were submitted to electroretinography and clinical analyses on days 3, 7, and 15 after uveitis induction. In addition, histopathological analysis, and indirect quantification of myeloperoxidase (MPO) and N-acetylglucosaminidase (NAG) in the posterior segment were performed. Treatment with lupeol (100 µM) significantly decreased IL-6 and IL-8 levels in comparison to untreated LPS-activated ARPE-19 cells. This reduction was similar to that detected in ARPE-19 cells treated with dexamethasone. The results of the in vivo assay demonstrated that intravitreal lupeol is able to modulate inflammation in the anterior and posterior segment of the rat eyes, indicating that it should be further investigated as a novel potential candidate for management of uveitis.

A Review of Ocular Drug Delivery Platforms and Drugs for Infectious and Noninfectious Uveitis: The Past, Present, and Future

Uveitis refers to a broad group of inflammatory disorders of the eye that often require medical and surgical management to improve or stabilize vision and prevent vision-threatening pathological changes to the eye. Drug delivery to the eye to combat inflammation and subsequent complications from uveitic conditions is complex as there are multiple barriers to absorption limiting availability of the needed drug in the affected tissues. As such, there has been substantial interest in developing new drugs and drug delivery platforms to help reduce intraocular inflammation and its complications. In this review, we discuss the challenges of drug delivery, novel technologies recently approved for uveitis patient care and promising drug delivery platforms for uveitis and sequelae of ocular inflammation.

Acute orbital inflammation with loss of vision: a paradoxical adverse event associated with infliximab therapy for Crohn's disease

Anti-TNF-α agents (e.g. infliximab, adalimumab, etanercept) are effective management options in various inflammatory and autoimmune diseases (e.g. inflammatory bowel disease). The occurrence during anti-TNF-α agent therapy of a new onset or exacerbation of an inflammatory condition that usually responds to this class of drug has been termed a paradoxical adverse event (PAE). A wide range of ophthalmic PAEs have been reported including uveitis, optic neuritis/neuropathy, scleritis, orbital myositis, retinal vasculitis, and others. The patient reported herein developed a dramatic orbital inflammatory PAE during his infliximab infusions, which manifested as an acute orbital apex syndrome with vision loss. Physicians using this medication should be aware of this serious vision-threatening PAE, and urgent therapy with high dose intravenous corticosteroids may be required.

Achieving Quiescence with Fluocinolone Implants

Persistent anterior uveitis causing cystoid macular oedema may necessitate either intraocular or systemic immunosuppression. This case report highlights how a newly licenced treatment, fluocinolone acetonide (Iluvien^®, Alimera Sciences Ltd., England, UK) achieves quiescence in refractory and steroid-dependent disease and in the presence of an acute relapse.

Dexamethasone implant migration in an eye with congenital glaucoma: A case report and review of the literature

INTRODUCTION

The dexamethasone (DEX) implant is an FDA approved treatment for diabetic macular edema, non-infectious posterior uveitis, and macular edema secondary to branch or central retinal vein occlusions. We describe a case of anterior chamber (AC) migration of a DEX implant in a patient with a history of congenital glaucoma and perform a review of the literature on this particular complication, summarizing the common risk factors, subsequent complications, and management options.

CASE DESCRIPTION

A 46-year-old female with a history of congenital glaucoma, status post cataract extraction with insertion of intraocular lens, pars plana vitrectomy, and Baerveldt tube implant in the left eye was referred for post-operative cystoid macular edema (CME). The patient underwent insertion of a DEX implant, resulting in improvement in her CME. After the fourth implant was injected, the patient noticed a white line in her eye while looking in the mirror after doing jumping jacks. Slit lamp examination confirmed migration of the implant into the AC. Ultimately, the patient was taken to the operating room, where her implant was removed via bimanual vitrectomy through an anterior approach.

CONCLUSION

This case report and literature review explores the ophthalmic structural changes specific to congenital glaucoma which may have predisposed this eye to anterior migration of the DEX implant. The purpose of this review is to detail the anatomic changes that may increase the risk of anterior chamber implant migration in patients with congenital glaucoma so that physicians may be aware of these risks when selecting patients for this implant.