Adding a Corticosteroid or Switching to Another Anti-VEGF in Insufficiently Responsive Wet Age-Related Macular Degeneration

Multifunctional nano-in-micro delivery systems for targeted therapy in fundus neovascularization diseases

Fundus neovascularization diseases are a series of blinding eye diseases that seriously impair vision worldwide. Currently, the means of treating these diseases in clinical practice are continuously evolving and have rapidly revolutionized treatment opinions. However, key issues such as inadequate treatment effectiveness, high rates of recurrence, and poor patient compliance still need to be urgently addressed. Multifunctional nanomedicine can specifically respond to both endogenous and exogenous microenvironments, effectively deliver drugs to specific targets and participate in activities such as biological imaging and the detection of small molecules. Nano-in-micro (NIM) delivery systems such as metal, metal oxide and up-conversion nanoparticles (NPs), quantum dots, and carbon materials, have shown certain advantages in overcoming the presence of physiological barriers within the eyeball and are widely used in the treatment of ophthalmic diseases. Few studies, however, have evaluated the efficacy of NIM delivery systems in treating fundus neovascular diseases (FNDs). The present study describes the main clinical treatment strategies and the adverse events associated with the treatment of FNDs with NIM delivery systems and summarizes the anatomical obstacles that must be overcome. In this review, we wish to highlight the principle of intraocular microenvironment normalization, aiming to provide a more rational approach for designing new NIM delivery systems to treat specific FNDs.

Role of traditional Chinese medicine in age-related macular degeneration: exploring the gut microbiota's influence

The pathogenesis of age-related macular degeneration (AMD), a degenerative retinopathy, remains unclear. Administration of anti-vascular endothelial growth factor agents, antioxidants, fundus lasers, photodynamic therapy, and transpupillary warming has proven effective in alleviating symptoms; however, these interventions cannot prevent or reverse AMD. Increasing evidence suggests that AMD risk is linked to changes in the composition, abundance, and diversity of the gut microbiota (GM). Activation of multiple signaling pathways by GM metabolites, including lipopolysaccharides, oxysterols, short-chain fatty acids (SCFAs), and bile acids (BAs), influences retinal physiology. Traditional Chinese medicine (TCM), known for its multi-component and multi-target advantages, can help treat AMD by altering GM composition and regulating the levels of certain substances, such as lipopolysaccharides, reducing oxysterols, and increasing SCFA and BA contents. This review explores the correlation between GM and AMD and interventions for the two to provide new perspectives on treating AMD with TCM.

Intravitreal Dexamethasone as a Rescue for Anti-Vascular Endothelial Growth Factor Therapy in Neovascular Age-Related Macular Degeneration with Persistent Disease Activity and High Treatment Demand

Purpose: To assess the impact of switching to, or adding, an intravitreal dexamethasone implant (Dex; Ozurdex®) in anti-vascular endothelial growth factor (VEGF) therapy on disease stability and treatment intervals in eyes with neovascular age-related macular degeneration (nAMD) and persistent disease activity and high treatment demand. Methods: This retrospective noncomparative multicenter longitudinal case series included pseudophakic eyes with nAMD and persistent retinal fluid despite regular anti-VEGF therapy (ranibizumab or aflibercept) that received at least 1 intravitreal Dex implant. Visual acuity, central retinal thickness (CRT), and intraocular pressure were recorded before, and after, the addition of Dex to anti-VEGF therapy. Results: Sixteen eyes of 16 patients met the inclusion criteria of persistent fluid despite anti-VEGF therapy, under treatment intervals of ≤7 weeks in 14 instances. Patients were 80.9 ± 7.4 years old and had received 25.5 ± 17.4 anti-VEGF injections before Dex over a period of 36.4 ± 21.9 months before switching. The treatment interval increased from 5.5 ± 3.2 weeks between the last anti-VEGF and first Dex injection to 11.7 ± 7.3 weeks thereafter (P = 0.022). CRT remained stable (385.3 ± 152.1, 383.9 ± 129.7, and 458.3 ± 155.2 μm before switching as well as 12 and 24 months after switching; P = 0.78 and P = 0.36, respectively). An insignificant mean short-term early increase in visual acuity was not sustained over time. Conclusions: The addition of Dex resulted in a relevant and sustained increase in treatment intervals, whereas CRT and visual acuity remained stable in these difficult-to-treat eyes. It may be discussed whether inflammation or other steroid-responsive factors play a significant role in cases of nAMD with nonsatisfactory responses to anti-VEGF.

Central posterior hyaloid fibrosis: evolution and outcomes

PURPOSE

To report contributory factors and clinical outcomes of central posterior hyaloid fibrosis (CPHF) associated with neovascular age-related macular degeneration (nAMD).

METHODS

In this retrospective, single-center study, patients with CPHF and nAMD were included. Demographic and imaging characteristics, as well as the anatomical and functional outcomes, of these patients were analysed.

RESULTS

We identified 530 eyes in 273 patients with chronic predominantly scarred macular neovascularisation (MNV), and 32 eyes in 29 patients revealed CPHF, representing a prevalence of 6%. Patients had a mean age of 72.76 years. Before and during the development of CPHF, Type 2 MNV was observed in all eyes. At the time of MNV diagnosis, mean logMAR visual acuity was 1.308 ± 0.559 (20/407). The average time to develop CPHF was 27.3 months since the diagnosis of MNV. At the time of CPHF identification, the mean logMAR visual acuity was 1.498 ± 0.374 (20/630). RPE tear was observed in 6% (n = 2) of CPHF eyes. The average number of intravitreal anti-VEGF injections administered prior to the diagnosis of CPHF was 2.4 and after the onset of CPHF was 0.9. The final visual acuity was not significantly different at the final follow-up visit [1.304 ± 0.42 (20/402); p = 0.646].

CONCLUSION

Rarely observed in eyes with predominantly scarred subfoveal type 2 MNVs and extensive subretinal fibrosis, CPHF is associated with poor visual outcomes. Its presence could possibly suggest a profibrotic effect of MNV on the posterior hyaloid.

TRIAL REGISTRATION NUMBER

Not applicable.

SUSTAINED BIWEEKLY AFLIBERCEPT FOR REFRACTORY NEOVASCULAR AGE-RELATED MACULAR DEGENERATION: The Prospective TRISTAR Study

PURPOSE

To assess the safety and efficacy of biweekly (every 2 weeks) intravitreal aflibercept injections (IAI) 2 mg in eyes with refractory neovascular age-related macular degeneration (NVAMD).

METHODS

A prospective, single-arm, interventional study was conducted. Eyes with refractory NVAMD received six biweekly IAIs through week 12, followed by a 4-week treatment pause until week 16. Eyes with residual subretinal fluid (SRF) at week 16 were randomized 1:1 to either four additional biweekly IAIs or to 4-week (q4W) IAI dosing through week 24. All eyes were subsequently treated q4W through week 52.

RESULTS

Enrolled eyes (n = 22) had persistent SRF despite a mean of 11.8 injections over the prior 12 months. One patient developed endophthalmitis at week 12. There were no additional drug/procedure-related adverse events. Best-corrected visual acuity (BCVA) improved significantly from baseline to week 14 (2.52 letters, P < 0.001). The mean central subfield thickness (CST) was also significantly improved at week 14 (-31.9 µ m, P < 0.001) with eight of 22 eyes achieving complete SRF resolution. Only two of eight eyes remained free of SRF at week 16, with a corresponding increase in mean CST of 26.7 µ m compared with week 14. By week 52, improvements in BCVA and CST were lost.

CONCLUSION

In patients with refractory NVAMD-related SRF, sustained biweekly IAIs resulted in significant functional and anatomical improvements during biweekly dosing. These gains, however, were lost on return to monthly dosing. These findings suggest that efforts to reduce refractory SRF in NVAMD with biweekly dosing may provide added benefit compared with standard of care treatment if biweekly dosing is sustained.

Simultaneous Release of Aflibercept and Dexamethasone from an Ocular Drug Delivery System

PURPOSE

Intravitreal injections of anti-vascular endothelial growth factors (anti-VEGF) are the current standard of care for patients with choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD). There is a growing subset of patients that does not respond to anti-VEGF monotherapy treatment. Some patients, however, do respond to combination therapy of corticosteroids and anti-VEGF. This treatment requires monthly/bimonthly injections of anti-VEGF and semi-annual injections of corticosteroid. A drug delivery system (DDS) that simultaneously releases multiple drugs could benefit these patients by reducing the number of injections. The purpose of this study was to characterize the simultaneous release of aflibercept and dexamethasone from a biodegradable microparticle- and nanoparticle-hydrogel DDS.

METHODS

Dexamethasone-loaded nanoparticles and aflibercept-loaded microparticles were created using modified single- and double-emulsion techniques, respectively. Then, microparticles and nanoparticles were embedded into a thermoresponsive, biodegradable poly(ethylene glycol)-co-(L-lactic acid) diacrylate (PEG-PLLA-DA)-N-isopropylacrylamide (NIPAAm) hydrogel DDS. Drug release studies and characterization of DDS were conducted with varying doses of microparticles and nanoparticles.

RESULTS

The combination aflibercept-loaded microparticle- and dexamethasone-loaded nanoparticle- hydrogel (Combo-DDS) achieved a total release time of 224 days. Small decreases were seen in swelling ratio and equilibrium water content for Combo-DDS compared to monotherapy aflibercept-loaded microparticle-hydrogel DDS (AFL-DDS) and monotherapy dexamethasone-loaded nanoparticle-hydrogel DDS (DEX-DDS). Bioactivity of aflibercept was maintained in Combo-DDS compared to AFL-DDS.

CONCLUSIONS

The Combo-DDS was able to extend and control the release of both aflibercept and dexamethasone simultaneously from a single DDS. This may eliminate the need for separate dosing regiments of anti-VEGF and corticosteroids for wet AMD patients.

Long-Term Analysis of Clinical Features and Treatment Outcomes of Inflammatory Choroidal Neovascularization

PURPOSE

To investigate the long-term clinical features and treatment outcomes of patients with inflammatory choroidal neovascularization (CNV) treated with intravitreal anti-vascular endothelial growth factor (anti-VEGF).

DESIGN

Retrospective, interventional, consecutive case series.

METHODS

Sixty-five eyes of 65 patients with inflammatory CNV treated with anti-VEGF injections and followed up at least 12 months were included. Retrospective chart review was conducted at a single tertiary referral center.

RESULTS

Study participants were followed up for 60.6 ± 42.8 (range, 16-160) months. Mean age was 33.4 ± 10.8 years, and mean refractive error was -3.94 ± 1.35 D in spherical equivalent. Final best-corrected visual acuity (BCVA) was 0.21 ± 0.20 logMAR after treatment. Patients were treated with bevacizumab (76.9%), ranibizumab (4.6%), aflibercept (3.1%), and drug combinations (15.4%). Systemic corticosteroid or immunosuppressant use was not correlated with visual outcome, required number of anti-VEGF injections, and recurrence. Commonly occurring optical coherence tomography (OCT) features included ellipsoid zone disruption, choroidal hypertransmission, retinal pigment epithelium atrophy or absence (RPEA), intraretinal hyperreflective foci (HRF), choroidal vessel engorgement, focal choroidal excavation, and irregular vascular loops (on OCT angiography). RPEA after treatment (β = 0.238, P = .036) and BCVA (β = 0.267, P = .029) showed significant correlation with final BCVA. A total of 28 patients (43.1%) experienced recurrence; intraretinal HRF after treatment was the single risk factor for recurrence (odds ratio = 2.712, P = .031).

CONCLUSIONS

Inflammatory CNV recurrence showed higher rates over time after anti-VEGF treatment than previously reported, even though the overall visual outcome was good. Baseline BCVA and RPEA after treatment are significant predictors for visual outcome. Intraretinal HRF after anti-VEGF treatment suggests the potential risk of recurrence.

Comparison of Intraocular Cytokine Levels of Choroidal Neovascularization Secondary to Different Retinopathies

Purpose: To investigate and compare the aqueous concentrations of vascular endothelial growth factor (VEGF) and other inflammatory cytokines in various choroidal neovascularization (CNV) diseases and types.

Methods: This observational study included 127 naive eyes with CNV and 43 control eyes with cataracts. Aqueous humor (AH) samples were obtained prior to intravitreal anti-VEGF injection or cataract surgery. Multiple inflammatory cytokines, including VEGF, interleukin (IL) 6, IL-8, IL-10, interferon-inducible protein 10 (IP-10), and monocyte chemotactic protein 1 (MCP-1) levels, were measured using a multiplex bead assay. The angiogenesis index was defined as the ratio of IP-10 to MCP-1. In addition, the relationship among AH cytokine levels, central macular thickness (CMT), and CNV size on optical coherence tomography angiography (OCTA) was evaluated.

Results: Except in the myopic CNV group (P = 0.452), the AH concentration of VEGF was significantly higher in all other CNV groups than in the control group (P < 0.05 for all comparisons). IL-8, IL-10, IP-10, and MCP-1 levels (P < 0.05 for all groups) were significantly higher in all CNV diseases except those with neovascular central serous chorioretinopathy. The angiogenesis index was significantly higher in all CNV diseases (P < 0.05 for all comparisons). The VEGF level may be associated with the size of the CNV on OCTA (p = 0.043).

Conclusions: The level of intraocular inflammatory cytokines varied among different CNV diseases and CNV types. Therefore, the angiogenesis index may be a more sensitive indicator of angiogenesis.

Switching to Brolucizumab in Neovascular Age-Related Macular Degeneration Incompletely Responsive to Ranibizumab or Aflibercept: Real-Life 6 Month Outcomes

Purpose: The aim of this study was to evaluate the effect of switching treatment in eyes with neovascular age-related macular degeneration (nAMD) and treatment intervals of ≤6 weeks to brolucizumab. Methods: In this prospective series, eyes with persisting retinal fluid under aflibercept or ranibizumab every 4–6 weeks were switched to brolucizumab. Visual acuity (BCVA), reading acuity (RA), treatment intervals, central subfield thickness (CST), and the presence of intra- and subretinal fluid were recorded over 6 months. Results: Seven of 12 eyes completed the 6 month follow-up and received 4.4 ± 0.5 brolucizumab injections within 28.0 ± 2.8 weeks. Treatment intervals increased from 5.3 ± 0.9 weeks to 9.0 ± 2.8 weeks (95% confidence interval of extension (CI): 1.6 to 5.9). BCVA improved from 67.8 ± 7.2 to 72.2 ± 7.5 (95% CI: −0.3 to 9.1) ETDRS letters, RA improved from 0.48 ± 0.15 to 0.31 ± 0.17 LogRAD (95% CI: 0.03 to 0.25), and CST improved from 422.1 ± 97.3 to 353.6 ± 100.9 µm (95% CI: −19.9 to 157.1). Treatment was terminated early in five eyes (two intraocular inflammations with vascular occlusion without vision loss, one stroke, and two changes in the treatment plan). Conclusions: Improvement in visual performance and longer treatment intervals in our series over 6 months indicate the potential of brolucizumab to reduce the treatment burden in nAMD, while two instances of intraocular inflammation were encountered.

Biological drug therapy for ocular angiogenesis: Anti-VEGF agents and novel strategies based on nanotechnology

Currently, biological drug therapy for ocular angiogenesis treatment is based on the administration of anti‐VEGF agents via intravitreal route. The molecules approved with this purpose for ocular use include pegaptanib, ranibizumab, and aflibercept, whereas bevacizumab is commonly off‐label used in the clinical practice. The schedule dosage involves repeated intravitreal injections of anti‐VEGF agents to achieve and maintain effective concentrations in retina and choroids, which are administrated as solutions form. In this review article, we describe the features of different anti‐VEGF agents, major challenges for their ocular delivery and the nanoparticles in development as delivery system of them. In this way, several polymeric and lipid nanoparticles are explored to load anti‐VEGF agents with the aim of achieving sustained drug release and thus, minimize the number of intravitreal injections required. The main challenges were focused in the loading the molecules that maintain their bioactivity after their release from nanoparticulate system, followed the evaluation of them through studies of formulation stability, pharmacokinetic, and efficacy in in vitro and in vivo models. The analysis was based on the information published in peer‐reviewed published papers relevant to anti‐VEGF treatments and nanoparticles developed as ocular anti‐VEGF delivery system.

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

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