Recent developments in the treatment of age-related macular degeneration

Exploring the protective effects of Qiju Granule in a rat model of dry age-related macular degeneration

AIM

The aim of this study was to evaluate the potential protective effect of Qiju Granule in a rat model of age-related macular degeneration (AMD) and investigate the underlying mechanisms involved.

METHODS

Rats were injected intravenously with 40 mg/kg of sodium iodate (SI) to induce a dry AMD model. The rats in the treatment group received three different doses of Qiju Granule once a day via gavage, while the rats in the control group were given an equal volume of physiological saline. On day 14 and day 28 following the intervention, various methods were employed to evaluate retinal function and structure, including electroretinography (ERG), optical coherence tomography (OCT), and histological examination. The expression of glial fibrillary acidic protein (GFAP), basic fibroblast growth factor (bFGF), brain-derived neurotrophic factor (BDNF), and ciliary neurotrophic factor (CNTF) was assessed via immunofluorescence. Beyond immunofluorescence, the mRNA levels of bFGF, BDNF, and CNTF were quantitatively determined using real-time polymerase chain reaction (qRT-PCR).

RESULTS

Rats treated with Qiju Granule exhibited significant improvements in both retinal function and structure compared to the model group. The most noteworthy effects were observed at a high dose of Qiju Granule. Furthermore, the expression levels of bFGF, BDNF, and CNTF were significantly unregulated in the treated groups compared to the model group.

CONCLUSIONS

Qiju Granule demonstrated a protective effect on the retina in the SI-induced rat model of AMD. The protective mechanism may be attributed to the upregulation of retinal neurotrophic factors expression.

Italian Patient Satisfaction with wAMD Management: SWAN Study Results

Purpose

Limited data is available on treatment satisfaction with the management of wet age-related macular degeneration (wAMD) among patients in Italy. In this cross-sectional real-world study, treatment satisfaction with anti-vascular endothelial growth factor (anti-VEGFs) was assessed in patients with wAMD in Italy.

Patients and Methods

This was a non-interventional, cross-sectional survey involving patients with wAMD receiving anti-VEGFs. The survey was administered through a virtual assistant via phone. Patients' treatment satisfaction was assessed using a newly developed Novartis Tailored Treatment Satisfaction Questionnaire (NVS TTSQ) and the validated Macular Disease Treatment Satisfaction Questionnaire (MacTSQ).

Results

Overall, 154 evaluable patients were enrolled in 5 centers across Italy. The mean (SD) age of the patients was 76.8 years (7.01). Overall treatment satisfaction score assessed by NVS TTSQ was 40.50 (7.11), with a mean of 9.97 (1.84) on the information domain and 22.98 (4.57) on the unmet need domain. Patients were satisfied with diagnosis communication (4.99 [1.30]), information provided on treatment administration (4.58 [1.49], range 0-6), the waiting room (4.40 [1.43]), and management of visits and injections at the center (5.14 [1.12]), general management of maculopathy at the center (5.22 [1.01]). Patients were not satisfied with their independence in terms of disease management (2.56 [2.45]); they would like additional information about the disease (5.38 [1.03]) and to discuss the injection procedures (4.02 [1.94]) with already-treated patients. The overall treatment satisfaction score on MacTSQ scale was 55.84 (10.13).

Conclusion

Patients with wAMD are satisfied with the overall management of their disease in Italy. However, patients would like to have more information on prognosis and management of the disease.

The complement pathway as a therapeutic target for neovascular age-related macular degeneration-mediated subretinal fibrosis

Neovascular age-related macular degeneration (nAMD) is the leading cause of blindness in the elderly in developed countries. Intravitreal injection of VEGF inhibitors is the mainstream therapy for nAMD, although nearly 50% of the patients do not respond or respond poorly to the therapy. One of the main reasons for the poor outcome of the therapy is the development of subretinal macular fibrosis, a process of excessive deposition of extracellular matrix proteins around the diseased blood vessels. Currently, there is no medication to prevent or treat the condition. Here, we discussed recent advances in the pathogenesis of nAMD-mediated macular fibrosis, with a focus on the role of the complement system. We further proposed approaches to target the complement system for the management of macular fibrosis and highlighted the area of further research for future clinical applications of complement-based therapy.

Eyedrop delivery of therapeutic proteins with zwitterionic polymers to treat dry age-related macular degeneration

In clinics, therapeutic proteins are commonly used to treat retinal diseases through intraocular injection, the treatment which suffers from rather low patient compliance. Topical administration (e.g. eye-drops) of large molecule drugs remains a major challenge due to the presence of various barriers in the eye. In this study, zwitterion-grafted chitosan (CS-ZW) was developed and then self-assembled with protein therapeutics including adalimumab (ADA) or catalase (CAT) for the treatment of dry age-related macular degeneration (dAMD) via topical eyedrops. Since CS-ZW can cross the mucus layer and open the tight junctions between epithelial cells, their delivered therapeutic proteins can be shuttled across the ocular barriers to reach the diseased site in the fundus. CS-ZW/ADA eyedrops delivering ADA to bind TNF-α in the fundus achieved a similar therapeutic effect to intravitreal ADA injection in a mouse dAMD model. In addition, the therapeutic effect was further improved by combining eyedrop formulations of CS-ZW/ADA and CS-ZW/CAT, the latter of which can clear reactive oxygen species (ROS) in the lesion to further assist dAMD treatment. Our work provides a simple and effective delivery vehicle that can non-invasively treat fundus diseases such as dAMD, showing potential advantages in reducing side effects associated with intraocular injection and improving patient compliance.

A bioengineered anti-VEGF protein with high affinity and high concentration for intravitreal treatment of wet age-related macular degeneration

Intravitreal (IVT) injection of anti-vascular endothelial growth factor (anti-VEGF) has greatly improved the treatment of many retinal disorders, including wet age-related macular degeneration (wAMD), which is the third leading cause of blindness. However, frequent injections can be difficult for patients and may lead to various risks such as elevated intraocular pressure, infection, and retinal detachment. To address this issue, researchers have found that IVT injection of anti-VEGF proteins at their maximally viable concentration and dose can be an effective strategy. However, the intrinsic protein structure can limit the maximum concentration due to stability and solution viscosity. To overcome this challenge, we developed a novel anti-VEGF protein called nanoFc by fusing anti-VEGF nanobodies with a crystallizable fragment (Fc). NanoFc has demonstrated high binding affinity to VEGF165 through multivalency and potent bioactivity in various bioassays. Furthermore, nanoFc maintains satisfactory chemical and physical stability at 4°C over 1 month and is easily injectable at concentrations up to 200 mg/mL due to its unique architecture that yields a smaller shape factor. The design of nanoFc offers a bioengineering strategy to ensure both strong anti-VEGF binding affinity and high protein concentration, with the goal of reducing the frequency of IV injections.

Retinal vascular structure independently predicts the initial treatment response in neovascular age-related macular degeneration

PURPOSE

Prediction of the early treatment response is important in neovascular age-related macular degeneration (nAMD). Hence, we aimed to test if non-invasive measurements of the retinal vascular structure were able to predict a successful outcome of initial intravitreal treatment.

METHODS

In 58 eyes of 58 patients with treatment-naïve nAMD, advanced markers of retinal vascular structure were measured by Singapore I Vessel Assessment prior to initial intravitreal treatment with three monthly injections of aflibercept with subsequently categorization of patients as full treatment responders (FTR) or non/partial treatment responders (N/PR), with the former defined as loosing fewer than five Early Treatment Diabetic Retinopathy Study letters and having no residual intra- or subretinal fluid or macular haemorrhage.

RESULTS

Of 54 eyes attending follow-up, 44.4% were categorized as FTR. Patients with FTR were older (81.5 vs. 77 years, p = 0.04), and prior to treatment those eyes had a lower retinal arteriolar fractal dimension (Fd) (1.21 vs. 1.24 units, p = 0.02) and venular length-diameter ratio (LDR) (7.3 vs. 15.9 units, p = 0.006), but did not differ with respect to other retinal vascular parameters. In multiple logistic regression models, a lower chance of FTR was independently predicted by a higher retinal venular LDR (odds ratio [OR] 0.91, 95% CI 0.82-0.99, p = 0.03, for each 1 unit increment) and marginally by a higher retinal arteriolar Fd (OR 0.83, 95% CI 0.68-1.00, p = 0.05, for each 0.01 unit increment).

CONCLUSION

Retinal venular LDR independently predicted the initial treatment response in nAMD. If confirmed by long-term, prospective studies, this might help to guide treatment.

Polymeric Propranolol Nanoparticles for Intraocular Delivery: Formulation, Characterization, and Vitreous Pharmacokinetics

Purpose

Recent studies have reported the promising effect of intravitreal propranolol on retinal neovascularization. However, rapid clearance and short half-life of the drug in the vitreous are the main drawbacks of this therapeutic approach. This study investigates the extension of the residence time of propranolol in the vitreous by polymeric nanoparticles (NPs) with the prospect of improving choroidal neovascularization treatment.

Methods

The poly (lactic-co-glycolic) acid (PLGA) NPs were fabricated by a modified double emulsion solvent evaporation method and the obtained NPs were characterized for their size, poly dispersity index (PDI), and surface image. The in vitro release, cell cytotoxicity, and uptake of NPs were also evaluated. To investigate the effect of the vitreous pharmacokinetic drug loaded NPs versus that of the free propranolol, they were intravitreally injected into the rabbits' eyes and the drug vitreous concentrations in defined intervals were analyzed by high performance liquid chromatography (HPLC).

Results

The spherical NPs with about 230 nm size, and almost 10% drug loading were obtained. Based on the 3-(4, 5-Dimethylthiazol-2-Yl)-2, 5-Diphenyltetrazolium Bromide (MTT) outcomes, 30 µg/ml of propranolol was considered as the guide dosage in the intravitreal injection. Confocal microscopy images verified the presence of labeled NPs in the posterior segment after five days of receiving the injection. In vivo assay revealed that the vanishing rate of propranolol in rabbits treated with propranolol NPs was reduced at twice the rate as compared to that of the vanishing rate experienced with only the free drug.

Conclusion

PLGA NPs can prolong the existence of propranolol in both vitreous and posterior ocular tissues, and thus, may provide an effective approach in treatment of posterior segment neovascularization.

Application of Nanoscopic Quantum Systems in Retinal Restoration

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Correlation of the OCT Double-Layer Sign with Type 1 Non-Exudative Neovascularization on OCT-A in Age-Related Macular Degeneration

Background and Objectives: Early diagnosis of the exudative form of age-related macular degeneration (AMD) is very important for a timely first treatment, which is directly related to the preservation of functional visual acuity over a long period. The goal of this paper was to examine the correlation between the double-layer sign (DLS) and the presence of non-exudative macular neovascularization (MNV). Materials and Methods: Our research included 60 patients with AMD, exudative in one eye and non-exudative in the other eye. We analyzed only the non-exudative form using optical coherence tomography (OCT) and optical coherence tomography angiography (OCT-A). The patients were classified into three groups, depending on the duration of the disease (<2 years, 2 to 5 years, >5 years). The onset of the disease was deemed the moment of establishing a diagnosis of exudative AMD in one eye. We defined the presence or absence of a DLS using OCT and the presence of non-exudative MNV using OCT-A, both on 3 × 3 mm and 6 × 6 mm sections. DLS was used as a projection biomarker for non-exudative MNV, with the aim of establishing a rapid diagnosis and achieving early treatment of the disease. Results: We found that there was a statistically significant correlation between the DLS diagnosed using OCT and non-exudative MNV diagnosed by OCT-A for both 3 × 3 mm (p < 0.001) and 6 × 6 mm (p < 0.001) imaging. There was a statistically significant difference between the frequencies of both DLS and MNV in Groups I and III on both 3 × 3 and 6 × 6 mm imaging. A statistically significant difference was also noted in the frequencies of DLS and MNV on 6 × 6 mm imaging, but not on 3 × 3 mm imaging, between Groups I and II. No differences were found between the frequencies of DLS and MNV between Groups II and III. Conclusions: The DLS on OCT can be used as a projection biomarker to assess the presence of a non-exudative MNV.

Short-term Efficacy and Safety of Intravitreal Brolucizumab Injection for Treatment-Naive Exudate Age-related Macular Degeneration: A Multicenter Study

PURPOSE

To compare short-term efficacy and safety of intravitreal brolucizumab injection with aflibercept in treatment-naive neovascular age-related macular degeneration (nAMD) patients.

METHODS

A total of 59 eyes from 59 treatment-naive nAMD patients in three hospitals were retrospectively reviewed. Of which, 27 patients underwent intravitreal brolucizumab injections and 32 received aflibercept. After monthly consecutive three injections, best-corrected visual acuity (BCVA; in logarithm of minimal angle of resolution [logMAR]), central macular thickness (CMT), dry macula achievement rate, and intraocular inflammation (IOI) incidence were compared.

RESULTS

After loading-phase treatment, BCVA was significantly increased from 0.48 ± 0.30 logMAR at baseline to 0.33 ± 0.21 logMAR at 3 months in the brolucizumab group (p = 0.002) and 0.40 ± 0.39 logMAR at baseline to 0.33 ± 0.36 logMAR at 3 months in the aflibercept group (p = 0.007). But there was no significant difference in BCVA improvement at 3 months between the two groups. CMT significantly decreased from 429.67 ± 250.59 μm at baseline to 210.67 ± 93.53 μm at 3 months in the brolucizumab group and from 346.69 ± 159.09 μm to 234.52 ± 83.42 μm in the aflibercept group (both p < 0.001). The amount of CMT reduction was significantly greater in the brolucizumab group after 3 months (p = 0.036). In typical AMD eyes, brolucizumab showed similar BCVA improvement but better CMT reduction at 3 months (p = 0.018). Dry macula achievement rate was not significantly different between the two groups. One IOI was observed in the brolucizumab group.

CONCLUSIONS

Intravitreal injections of brolucizumab and aflibercept showed similar anatomical and functional outcomes. But CMT reduction was greater in the brolucizumab group. One IOI was identified, which was tolerable for topical agents. These results suggest that brolucizumab could be a novel first line treatment option for treating naive nAMD patients.

Detection and Management of Intraocular Inflammation after Brolucizumab Treatment for Neovascular Age-Related Macular Degeneration

PURPOSE

To present interim descriptive insights from the OCTOPUS and SWIFT studies on incidence, clinical features, management, and outcomes of intraocular inflammation (IOI), vasculitis, and occlusive vasculitis with brolucizumab treatment (Beovu, Novartis) in patients with neovascular age-related macular degeneration (nAMD) who were anti-VEGF naive or pretreated with anti-VEGFs (ranibizumab or aflibercept).

DESIGN

OCTOPUS (NCT04239027) and SWIFT (NCT04264819) studies are prospective phase IIIb single-arm, open-label, multicenter studies assessing brolucizumab.

SUBJECTS

Anti-VEGF naive (OCTOPUS) and pretreated (SWIFT) patients with nAMD.

METHODS

Interim prespecified analysis on the efficacy end point provided an opportunity to analyze IOI-related safety. Reports of IOI-related adverse events (AEs) were reviewed, and AE images and clinical features and outcomes of each case were analyzed by a review committee.

RESULTS

Of 505 brolucizumab-treated eyes/patients with median brolucizumab treatment of 8.8 months, 53 eyes demonstrated at least 1 IOI-related AE. The incidence of overall IOI-related AEs was 10.5%; among these events, the incidence was 7.1% for IOI only without retinal involvement and 3.4% for IOI with retinal involvement (2.0% with vasculitis, 1.4% with vascular occlusion with or without vasculitis). Incidence was similar in naive and pretreated patients. Before the onset of the first IOI-related AE, eyes received a median of 2 brolucizumab injections; 81.1% of IOI-related AEs occurred during the loading phase (median, 25.0 days from the last brolucizumab injection). At AE onset, most frequently reported symptoms were floaters (52.8%) and blurred or decreased vision (37.8%). Of the 86.8% of AEs that were treated, most were treated with topical corticosteroids (75.5%), 28.3% by systemic corticosteroids, and 26.8% by intraocular corticosteroids. No severe vision loss was reported for the 7 nontreated AEs. Overall, the median best-corrected visual acuity (BCVA) change at IOI-related AEs resolution from baseline was 1 letter (range, -74 to +32 letters), and 2 patients with occlusive vasculitis had BCVA loss ≥ 15 letters due to IOI-related AEs. All eyes permanently discontinued brolucizumab after the first IOI-related AE.

CONCLUSIONS

This analysis highlights the need for monitoring and education of patients to report any signs of IOI-related events immediately when being treated with brolucizumab. IOI should be treated promptly and intensely with corticosteroids.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Management of Neovascular Age-Related Macular Degeneration Treatment in France from 2008-2018: The Nationwide LANDSCAPE Study

INTRODUCTION

The aim of this study was to describe the management of neovascular age-related macular degeneration (nAMD) in French patients between 2008 and 2018.

METHODS

This was a retrospective longitudinal cohort study using exhaustive nationwide health records from the French National Health Information database. Enrollment criteria were adults aged ≥ 50 years, nAMD diagnosis, or reimbursement for nAMD treatments (anti-vascular epithelial growth factor [VEGF] injection or dynamic phototherapy with verteporfin). Exclusion criteria were high myopia, diagnosis of other retinal diseases, and treatments for other macular diseases (dexamethasone implant, laser). Main outcome measures were consumption of medical care and nAMD treatments per calendar year and number of years of follow-up.

RESULTS

Between 2008 and 2018, we identified 342,961 patients who have been treated for nAMD. Median duration of ophthalmological follow-up exceeded 7 years (90 months). The median annual number of ophthalmology consultations decreased from nine visits in year 1 after treatment initiation to four visits from year 7 onwards. The median duration of nAMD treatment was 10.1 months for all patients, with 48.5% of patients undergoing treatment for < 1 year. Only 24.4% of patients had maintained treatment at year 11. Patients remaining under treatment had a median of four anti-VEGF treatments per year throughout the 10-year study period. Ranibizumab was the more common first-line treatment (67.5% of patients) compared to aflibercept (32.4%). About 20% of patients who initiated treatment switched treatment at least once.

CONCLUSIONS

LANDSCAPE provides exhaustive nationwide data on the real-world management of nAMD in France over a 10-year period. Further investigation into short treatment duration is required, especially in terms of understanding its relation to visual outcomes.

Progress in Stem Cells-Based Replacement Therapy for Retinal Pigment Epithelium: In Vitro Differentiation to In Vivo Delivery

Retinal pigment epithelium (RPE) is a critical cell monolayer forming the blood-retina-barrier (BRB) and a permeable bridge between the choriocapillaris and the retina. RPE is also crucial in maintaining photoreceptor function and for completing the visual cycle. Loss of the RPE is associated with the development of degenerative diseases like age-related macular degeneration (AMD). To treat diseases like AMD, pluripotent stem cell-derived RPE (pRPE) has been recently explored extensively as a regenerative module. pRPE like other ectodermal tissues requires specific lineage differentiation and long-term in vitro culturing for maturation. Therefore, understanding the differentiation process of RPE could be useful for stem cell-based RPE derivation. Developing pRPE-based transplants and delivering them into the subretinal space is another aspect that has garnered interest in the last decade. In this review, we discuss the basic strategies currently employed for stem cell-based RPE derivation, their delivery, and recent clinical studies related to pRPE transplantation in patients. We have also discussed a few limitations with in vitro RPE culture and potential solutions to overcome such problems which can be helpful in developing functional RPE tissue.

Therapeutic Benefit of Melatonin in Choroidal Neovascularization During Aging Through the Regulation of Senescent Macrophage/Microglia Polarization

Purpose

This study aimed to investigate the age-dependent anti-angiogenic capability of melatonin in choroidal neovascularization (CNV) and to explore the underlying molecular mechanisms.

Methods

In the present study, a laser-induced CNV model was established in both young (three months of age) and old (18 months of age) mice, and the size of CNV lesions and vascular leakage was detected by morphological and imaging examination. Next, Western blot and immunostaining were used to observe the levels of M2 markers, senescence-related markers, and molecules involved in IL-10/STAT3 pathway. Additionally, colivelin was used to study the effect of IL-10/STAT3 pathway activation on the expression of M2 markers and senescence-related markers by Western blot and immunostaining. Finally, the effects of colivelin on melatonin-induced reduction of CNV size and vascular leakage in mice at different ages were assessed using morphological and imaging examination.

Results

Our results revealed that aging promoted M2 macrophage/microglia polarization, and aggravated CNV and vascular leakage. Melatonin significantly inhibited the M2 polarization of senescent macrophage/microglia and reduced the CNV area and vascular leakage. Moreover, melatonin markedly suppressed IL-10/STAT3 pathway activation in the macrophage/microglia of old mice, and STAT3 activator colivelin reversed the suppressive effect of melatonin on M2 polarization of senescent macrophage/microglia and laser-induced CNV in old mice.

Conclusions

Our data demonstrated that melatonin significantly prevented the M2 polarization of senescent macrophage/microglia by inhibiting the IL-10/STAT3 pathway, and eventually attenuated senescence-associated CNV. These findings suggested that melatonin could serve as a promising therapeutic agent to treat CNV and other age-related ocular diseases.

Purinergic signaling via P2X receptors and mechanisms of unregulated ATP release in the outer retina and age-related macular degeneration

Age-related macular degeneration (AMD) is a chronic and progressive inflammatory disease of the retina characterized by photoceptor loss and significant central visual impairment due to either choroidal neovascularization or geographic atrophy. The pathophysiology of AMD is complex and multifactorial, driven by a combination of modifiable and non-modifiable risk factors, molecular mechanisms, and cellular processes that contribute to overall disease onset, severity, and progression. Unfortunately, due to the structural, cellular, and pathophysiologic complexity, therapeutic discovery is challenging. While purinergic signaling has been investigated for its role in the development and treatment of ocular pathologies including AMD, the potential crosstalk between known contributors to AMD, such as the complement cascade and inflammasome activation, and other biological systems, such as purinergic signaling, have not been fully characterized. In this review, we explore the interactions between purinergic signaling, ATP release, and known contributors to AMD pathogenesis including complement dysregulation and inflammasome activation. We begin by identifying what is known about purinergic receptors in cell populations of the outer retina and potential sources of extracellular ATP required to trigger purinergic receptor activation. Next, we examine evidence in the literature that the purinergic system accelerates AMD pathogenesis leading to apoptotic and pyroptotic cell death in retinal cells. To fully understand the potential role that purinergic signaling plays in AMD, more research is needed surrounding the expression, distribution, functions, and interactions of purinergic receptors within cells of the outer retina as well as potential crosstalk with other systems. By determining how these processes are affected in the context of purinergic signaling, it will improve our understanding of the mechanisms that drive AMD pathogenesis which is critical in developing treatment strategies that prevent or slow progression of the disease.

Is there any association between the frequency of wet age-related macular degeneration recurrences and the seasons of the year?

PURPOSE

To investigate whether a seasonal distribution of the frequency of exudative age-related macular degeneration (wet AMD) recurrences exists.

METHODS

In total, 129 eyes with 171 recurrences in patients suffering from wet AMD were included in the study. All the patients had been treated with intravitreal anti-VEGF injections according to Pro Re Nata treatment regimen. Recurrence was defined as the re-detection of sub-retinal fluid, intraretinal fluid, and/or sub-macular hemorrhage in optical coherence tomography scans, after at least two consecutive monthly examinations with a "dry" macula. The year was divided in three 4-month periods (zone A: June-September, zone B: October-January, and zone C: February-May) based on the weather conditions prevailing in each period. Mean temperature and hours of sunlight exposure were the main weather markers recorded.

RESULTS

Eighty-two recurrences (48%) occurred during the period June-September, 50 (29.2%) during the period October-January, and 39 (22.8%) during the period February-May (Chi-square = 17.5, p < 0.001). Among the groups, neither patients' age (78 ± 8 years A, 76 ± 7 years B, and 79 ± 8 years C, p = 0.15) nor gender status (40% men A, 36% men B, and 51% men C, p = 0.35) differed significantly. Mean temperature was 27.6 ± 1.8 °C, 15.1 ± 4.6 °C, and 16.5 ± 4.4 °C in zones A, B, and C, respectively. Hours (h) of sunlight exposure (average hours/month) were 344 ± 34 h, 188 ± 42 h, and 223 ± 57 h in zones A, B, and C.

CONCLUSION

We demonstrated that the frequency of wet AMD recurrences is significantly elevated during the warmer months, possibly due to the higher levels of UV radiation and mean temperature. Further research is necessary to validate our findings.

Determinants of Incident Atherosclerotic Cardiovascular Disease Events and All-Cause Mortality in Patients With Age-Related Macular Degeneration: Prospective Cohort Study of UK Biobank

PURPOSE

Major risk factors of atherosclerotic cardiovascular disease (ASCVD) and mortality have been well-established in the general population. Our study is aimed at assessing longitudinal relationships between ASCVD risk factors and incident ASCVD events or all-cause mortality in patients with age-related macular degeneration (AMD).

METHODS

Multivariable-adjusted Cox proportional hazards models were used to study the association between cardiovascular risk factors with adjudicated incident ASCVD events and all-cause mortality outcomes followed until 2021. A restricted cubic spline approach was utilized to assess nonlinear associations between potential cardiovascular risk factors and ASCVD or mortality.

RESULTS

We identified 3508 eligible patients [mean (SD) age = 61.45 (6.43) years; 37.76% males] with AMD at baseline. During a median follow-up year of 12, there were 110 cases of ASCVD events and 186 cases of all-cause mortality. After multivariable adjustment, each 10 U/L increase of serum gamma-glutamyl transferase level was linearly associated with incident ASCVD [hazard ratio (HR) = 1.03, 95% CI = 1.00-1.07, Pnonlinear = 0.85)] in AMD. A history of chronic kidney disease (HR = 1.94, 95% CI = 1.09-3.46) and lower vitamin D [HR = 0.98, 95% CI = 0.97-0.99, per nanomoles per liter (nmol/L)] were significantly associated with all-cause mortality in patients with AMD, with the association between vitamin D and all-cause mortality presenting a U shape (Pnonlinear = 0.02). In contrast, risk factors significantly associated with ASCVD and all-cause mortality in healthy controls differed from patients with AMD.

CONCLUSIONS

Our findings demonstrate risk factors associated with ASCVD events and all-cause mortality among individuals with AMD differed from healthy controls and suggest the long-term management of risk factors in patients with AMD.

Treatment of neovascular age-related macular degeneration within 48 h from diagnosis improves long-term functional outcome

PURPOSE

To evaluate long-term visual and anatomical outcomes in neovascular age-related macular degeneration (nAMD) patients treated with anti-vascular endothelial growth factor (VEGF) agents depending on the time delay from confirmed diagnosis to treatment initiation.

MATERIALS AND METHODS

Seventy-three nAMD patients (73 eyes) treated with anti-VEGF agents for 12 months using the pro re nata regimen were included in this retrospective longitudinal study. Patients were split into 3 groups according to the time from diagnosis to first anti-VEGF injection: < 48 h (group 1); 48 h-7 days (group 2); > 7 days (group 3). Decimal best-corrected visual acuity (VA) and macular thickness (MT) were recorded at baseline and 1-2-, 3-4-, 6- and 12-month later. Furthermore, age, gender as well as the applied treatment and number of injections after 12 months of treatment were also registered and compared.

RESULTS

Long-term effect of the treatment demonstrated enhanced VA in group 1 patients compared with the rest of groups after 1-2-, 6-, and 12-month follow-up (P < 0.05). Positive effects of early treatment were additionally corroborated by the augmented percentage of patients with normal VA in the group 1 respect to the rest of groups over studied time points (P < 0.05). Moreover, the VA gain in nAMD at group 1 was obtained with a mean of 3.7 intravitreal injections over 1-year follow-up period. Regarding MT, non-significant difference was observed among groups.

CONCLUSIONS

An early initial treatment with VEGF inhibitors is critical to achieve the best functional benefits of this therapy in new-onset nAMD patients.

An intravitreal-injectable hydrogel depot doped borneol-decorated dual-drug-coloaded microemulsions for long-lasting retina delivery and synergistic therapy of wAMD

Sustained retina drug delivery and rational drug combination are considered essential for enhancing the efficacy of therapy for wet age-related macular degeneration (wAMD) due to the conservative structure of the posterior ocular segment and the multi-factorial pathological mechanism. Designing a drug co-delivery system that can simultaneously achieve deep penetration and long-lasting retention in the vitreous is highly desired, yet remains a huge challenge. In this study, we fabricated Bor/RB-M@TRG as an intravitreal-injectable hydrogel depot for deep penetration into the posterior ocular segment and long-lasting distribution in the retinal pigment epithelium (RPE) layer. The Bor/RB-M@TRG consisted of borneol-decorated rhein and baicalein-coloaded microemulsions (Bor/RB-M, the therapy entity) and a temperature-responsive hydrogel matrix (the intravitreal depot). Bor/RB-M exhibited the strongest in vitro anti-angiogenic effects among all the groups studied, which is potentially associated with improved cellular uptake, as well as the synergism of rhein and baicalein, acting via anti-angiogenic and anti-oxidative stress pathways, respectively. Importantly, a single intravitreal (IVT) injection with Bor/RB-M@TRG displayed significant inhibition against the CNV of wAMD model mice, compared to all other groups. Particularly, coumarin-6-labeled Bor/RB-M@TRG (Bor/C6-M@TRG) could not only deeply penetrate into the retina but also stably accumulate in the RPE layer for at least 14 days. Our design integrates the advantages of borneol-decorated microemulsions and hydrogel depots, offering a promising new approach for clinically-translatable retinal drug delivery and synergistic anti-wAMD treatment.

The Treatment Patterns with Brolucizumab in Germany (REALIZE) Study: A Retrospective Cohort Study Based on Longitudinal Prescription Data

INTRODUCTION

This study describes real-world treatment patterns in Germany for brolucizumab, an anti-vascular endothelial growth factor (anti-VEGF) therapy for neovascular age-related macular degeneration (nAMD).

METHODS

This single-arm retrospective cohort study used German patient-level prescription data. Patients aged ≥ 50 years, who received ≥ 1 brolucizumab prescription in one eye only (unilateral) and had a minimum of 12 months follow-up were included. Three cohorts were defined from the overall population: anti-VEGF treatment-naive patients ("treatment-naive"); anti-VEGF treatment-experienced patients ("treatment-experienced"); and of the treatment-experienced cohort, patients persistent on brolucizumab for 12 months ("treatment-experienced persistent"), i.e. who received ≥ 2 brolucizumab injections and did not discontinue or use other anti-VEGF agents in that period. Descriptive statistics were used to analyse patient characteristics and injection intervals.

RESULTS

A total of 2089 patients with at least 12 months follow-up and one brolucizumab injection were analysed. Most were female (58.1%), aged 80+ years (54.7%). A total of 539 (25.8%) were treatment-naive, 1550 (74.2%) treatment-experienced and, of those, 787 (50.8%) were persistent. Overall, the median (interquartile range, IQR) number of brolucizumab injections during the 12 months follow-up was 5.0 (3.0-8.0). In the treatment-naive and treatment-experienced sub-cohorts it was 5.0 (3.0-8.0) and 5.0 (3.0-9.0) injections, respectively. In the treatment-experienced persistent cohort the median (IQR) number of injections was 8.0 (5.0-10.0). In this same cohort, the median (IQR) treatment interval between anti-VEGF injections before switch to brolucizumab was 5.1 (4.0-8.0) weeks, whilst the brolucizumab interval at 12 months after switch was 8.0 (6.0-11.9) weeks. Of treatment-experienced patients, 67% extended their treatment interval and those with pre-switch intervals less than 6 weeks (< q6w), in particular, had meaningful treatment interval extensions.

CONCLUSION

Patients who switched to brolucizumab had a median treatment interval extension of about 3 weeks at 12 months. These results show that treatment with brolucizumab has the potential to reduce treatment burden in patients with nAMD in routine clinical practice.

"One stone and two birds" strategy to treat neovascular age-related macular degeneration by a novel retinoid drug, EYE-101

Choroidal neovascularization (CNV) is a typical pathological feature of neovascular age-related macular degeneration and has become a major cause of vision loss in the elderly. Current therapies require repeated intraocular injections of anti-VEGF drugs by inhibiting endothelial angiogenic effects, which is painful and may cause adverse effects on normal vascular and neuronal functions. Herein, we designed a novel retinoid drug, EYE-101, determined its therapeutic effects on CNV, and clarified the anti-angiogenic mechanism. The results show that administration of EYE-101 did not cause obvious cytotoxicity and ocular tissue toxicity at the concentrations less than 5 μM. Topical administration of EYE-101 could reduce choroidal sprouting, suppress laser-induced CNV formation, and decrease pericyte coverages on ocular vessels. Administration of EYE-101 also suppressed endothelial cell proliferation, migration, and tube formation and reduced pericyte proliferation, migration, recruitment towards endothelial cells. EYE-101 exerted its anti-angiogenic effects by targeting endothelial cells and pericytes via antagonizing Wnt/β-catenin signaling and PDGF signaling. Thus, EYE-101 administration may offer an"one stone and two birds" strategy for the prevention and treatment of ocular neovascular disorders.

Autophagy in age-related macular degeneration

Age-related macular degeneration (AMD) is the leading cause of visual impairment in the aging population with limited understanding of its pathogenesis and a lack of effective treatment. The progression of AMD is initially characterized by atrophic alterations in the retinal pigment epithelium, as well as the formation of lysosomal lipofuscin and extracellular drusen deposits. Damage caused by chronic oxidative stress, protein aggregation and inflammatory processes may lead to geographic atrophy and/or choroidal neovascularization and fibrosis. The role of macroautophagy/autophagy in AMD pathology is steadily emerging. This review describes selective and secretory autophagy and their role in drusen biogenesis, senescence-associated secretory phenotype, inflammation and epithelial-mesenchymal transition in the pathogenesis of AMD.Abbreviations: Aβ: amyloid-beta; AMBRA1: autophagy and beclin 1 regulator 1; AMD: age-related macular degeneration; ATF6: activating transcription factor 6; ATG: autophagy related; BACE1: beta-secretase 1; BHLHE40: basic helix-loop-helix family member e40; BNIP3: BCL2 interacting protein 3; BNIP3L/NIX: BCL2 interacting protein 3 like; C: complement; CALCOCO2/NDP52: calcium binding and coiled-coil domain 2; CARD: caspase recruitment domain; CDKN2A/p16: cyclin dependent kinase inhibitor 2A; CFB: complement factor B; DELEC1/Dec1; deleted in esophageal cancer 1; EIF2AK3/PERK: eukaryotic translation initiation factor 2 alpha kinase 3; EMT: epithelial-mesenchymal transition; ER: endoplasmic reticulum; ERN1/IRE1: endoplasmic reticulum to nucleus signaling 1; FUNDC1: FUN14 domain containing 1; GABARAP: GABA type A receptor-associated protein; HMGB1: high mobility group box 1; IL: interleukin; KEAP1: kelch like ECH associated protein 1; LAP: LC3-associated phagocytosis; LAMP2: lysosomal associated membrane protein 2; LIR: LC3-interacting region; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MTOR: mechanistic target of rapamycin kinase; NFE2L2: NFE2 like bZIP transcription factor 2; NLRP3; NLR family pyrin domain containing 3; NFKB/NFκB: nuclear factor kappa B; OPTN: optineurin; PARL: presenilin associated rhomboid like; PGAM5: PGAM family member 5, mitochondrial serine/threonine protein phosphatase; PINK1: PTEN induced kinase 1; POS: photoreceptor outer segment; PPARGC1A: PPARG coactivator 1 alpha; PRKN: parkin RBR E3 ubiquitin protein ligase; PYCARD/ASC: PYD and CARD domain containing; ROS: reactive oxygen species; RPE: retinal pigment epithelium; SA: secretory autophagy; SASP: senescence-associated secretory phenotype; SEC22B: SEC22 homolog B, vesicle trafficking protein; SNAP: synaptosome associated protein; SNARE: soluble N-ethylmaleimide-sensitive factor attachment protein receptor; SQSTM1/p62: sequestosome 1; STX: syntaxin; TGFB2: transforming growth factor beta 2; TRIM16: tripartite motif containing 16; TWIST: twist family bHLH transcription factor; Ub: ubiquitin; ULK: unc-51 like autophagy activating kinase; UPR: unfolded protein response; UPS: ubiquitin-proteasome system; V-ATPase: vacuolar-type H+-translocating ATPase; VIM: vimentin.

Pirfenidone Attenuates the EMT Process and the Secretion of VEGF in TGF-β2-Induced ARPE-19 Cells via Inhibiting the Activation of the NF-κB/Snail Signaling Pathway

Aim

Pirfenidone (PFD), an antifibrotic drug, has various beneficial functions such as antioxidant, antifibrotic, and anti-inflammatory effects. This study aimed to explore the molecular mechanisms underlying how PFD modulates retinal pigment epithelial (RPE) cells involved in neovascularization and subretinal fibrosis.

Methods

ARPE-19 cell lines were treated with transforming growth factor-beta 2 (TGF-β2) alone or in combination with PFD. RPE cell viability, as a consequence of PFD use, was determined by the CCK-8 assay. Cell migration was assessed by the wound closure assay and quantified by the Image J software. Protein expression of the following markers was measured by the western blot analysis: an epithelial cell marker and E-cadherin; mesenchymal cell markers, fibronectin, matrix metalloprotein-9 (MMP-9), and alpha-smooth muscle actin (α-SMA); a fibrotic marker and connective tissue growth factor (CTGF); an angiogenesis marker and vascular endothelial growth factor (VEGF); NF-κB/Snail. The mRNA levels of fibronectin and α-SMA were determined by quantitative real-time PCR. VEGF was quantitatively measured by the enzyme-linked immunosorbent assay.

Results

The cell viability assay revealed that PFD had no significant cytotoxic effect on RPE cells at concentrations of less than 1 mg/mL. The cell scratch assay showed that TGF-β2 stimulation significantly improved the migration of RPE cells and that PFD attenuated this effect. PFD significantly inhibited the TGF-β2-induced protein expression of E-cadherin and increased the TGF-β2-induced protein expression of fibronectin, MMP-9, α-SMA, CTGF, and VEGF in ARPE-19 cells. The mRNA expression of fibronectin and α-SMA was inhibited by PFD in TGF-β2-inducedARPE-19 cells. Additionally, the increased intracellular and supernatant expression of VEGF protein was suppressed by PFD. Mechanistically, RPE cells treated with PFD + TGF-β2 exhibited a decrease in phosphorylation of the NF-κB P65 subunit and activation of Snail, compared with the RPE cells treated with TGF-β2 alone.

Conclusion

PFD ameliorated TGF-β2-induced neovascularization and fibrosis by suppressing the NF-κB/Snail signaling pathway. Therefore, PFD may be a potential drug in the treatment of age-related macular degeneration.

Retinal Pigment Epithelium Cell Development: Extrapolating Basic Biology to Stem Cell Research

The retinal pigment epithelium (RPE) forms an important cellular monolayer, which contributes to the normal physiology of the eye. Damage to the RPE leads to the development of degenerative diseases, such as age-related macular degeneration (AMD). Apart from acting as a physical barrier between the retina and choroidal blood vessels, the RPE is crucial in maintaining photoreceptor (PR) and visual functions. Current clinical intervention to treat early stages of AMD includes stem cell-derived RPE transplantation, which is still in its early stages of evolution. Therefore, it becomes essential to derive RPEs which are functional and exhibit features as observed in native human RPE cells. The conventional strategy is to use the knowledge obtained from developmental studies using various animal models and stem cell-based exploratory studies to understand RPE biogenies and developmental trajectory. This article emphasises such studies and aims to present a comprehensive understanding of the basic biology, including the genetics and molecular pathways of RPE development. It encompasses basic developmental biology and stem cell-based developmental studies to uncover RPE differentiation. Knowledge of the in utero developmental cues provides an inclusive methodology required for deriving RPEs using stem cells.

Factors That Can Prolong Ocular Treatment Duration in Age-Related Macular Degeneration

Intravitreal injections of anti-vascular endothelial growth factor (VEGF) agents are used to treat wet age-related macular degeneration (wAMD); however, they are associated with a considerable treatment burden and poor real-world outcomes. The molecular size and charge of anti-VEGF agents influence drug pharmacokinetics in the vitreous and peak drug efficacy. This article reviews the established and novel strategies to prolong drug action, in the vitreal cavity, and thus reduce dosing frequency. Increased ocular residency can be attained by increasing drug size as with large molecules, such as KSI-301; adding polyethylene glycol to pegcetacoplan (APL-2) or avacincaptad pegol to increase molecular size; or binding to other targets that increase molecular size, such as vitreal albumin in the case of BI-X. Faricimab is a bispecific antibody in which the fragment crystallizable portion is engineered to prolong ocular residency and reduce systemic exposure. Conversely, small VEGF-binding molecules, such as brolucizumab, can be administered at higher clinical doses, with the potential for prolonged clinical activity versus larger molecules. Other important considerations include sustained drug delivery routes, such as the ranibizumab port delivery system or subconjunctival or suprachoroidal injection. More effective and longer-lasting treatments are needed for wAMD to prolong drug action and reduce dosing frequency. Several strategies are under investigation and the prevention of vision loss in patients with AMD or other retinal diseases may be attainable in the near future.

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

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

Does real-time artificial intelligence-based visual pathology enhancement of three-dimensional optical coherence tomography scans optimise treatment decision in patients with nAMD? Rationale and design of the RAZORBILL study

BACKGROUND/RATIONALE

Artificial intelligence (AI)-based clinical decision support tools, being developed across multiple fields in medicine, need to be evaluated for their impact on the treatment and outcomes of patients as well as optimisation of the clinical workflow. The RAZORBILL study will investigate the impact of advanced AI segmentation algorithms on the disease activity assessment in patients with neovascular age-related macular degeneration (nAMD) by enriching three-dimensional (3D) retinal optical coherence tomography (OCT) scans with automated fluid and layer quantification measurements.

METHODS

RAZORBILL is an observational, multicentre, multinational, open-label study, comprising two phases: (a) clinical data collection (phase I): an observational study design, which enforces neither strict visit schedule nor mandated treatment regimen was chosen as an appropriate design to collect data in a real-world clinical setting to enable evaluation in phase II and (b) OCT enrichment analysis (phase II): de-identified 3D OCT scans will be evaluated for disease activity. Within this evaluation, investigators will review the scans once enriched with segmentation results (i.e., highlighted and quantified pathological fluid volumes) and once in its original (i.e., non-enriched) state. This review will be performed using an integrated crossover design, where investigators are used as their own controls allowing the analysis to account for differences in expertise and individual disease activity definitions.

CONCLUSIONS

In order to apply novel AI tools to routine clinical care, their benefit as well as operational feasibility need to be carefully investigated. RAZORBILL will inform on the value of AI-based clinical decision support tools. It will clarify if these can be implemented in clinical treatment of patients with nAMD and whether it allows for optimisation of individualised treatment in routine clinical care.

The effects of crocetin on oxidative stress induced ARPE-19 cells by H2O2

The anti-apoptotic and antioxidant effects of crocetin was aimed to investigate on the oxidative damage model of ARPE-19 cells. The oxidative damage in ARPE cells was developed by H₂O₂ treatment at 800 μM. Different doses of crocetin (1-80 μM) were applied for 24 h, and the effects on viability were evaluated to find out the optimum drug dose. At first, three effective doses of crocetin (10, 20, 40 μM) on cell viability were selected for further analyses. The levels of superoxide dismutase (SOD), malondialdehyde (MDA) and glutathione (GSH) were determined, and the expression of pro-apoptotic Bax gene and anti-apoptotic Bcl-2 gene were evaluated. The most effective crocetin dose on cell viability was found to be 10 μM. After the H₂O₂ treatment, SOD and GSH were decreased and MDA were increased significantly (p = 0.011, 0.037, 0.018, respectively). Following the crocetin treatment at 10 μM, SOD and GSH activities were improved compared to the no drug group; and MDA level was declined remarkably (p = 0.022, 0.019, 0.029, respectively). The Bcl-2 level was significantly decreased (p < 0.01), while the Bax1 and Nrf2 expression and ROS level was increased significantly in the damage model group (p < 0.01). After the drug treatment, the Bax1 and Nrf2 expression level were decreased in all groups (p < 0.01). The increase in Bcl-2 expression was significant in crocetin 40 μM (p < 0.05) and the decrease in ROS level were significant in 20 μM and 40 μM doses of crocetin (p < 0.05). It has been shown that crocetin might be used as an antioxidant and anti-apoptotic agent on the hindering the effect of the oxidative damage. Following the development of the oxidative stress in the cells, crocetin reversed the damage signals. By the in vitro tests, it was shown that crocetin might be considered as an effective molecule to be used in the AMD treatment.

cGAS inhibition alleviates Alu RNA-induced immune responses and cytotoxicity in retinal pigmented epithelium

Background

The degeneration of retinal pigmented epithelium (RPE) cells results in severe diseases, such as age-related macular degeneration (AMD) that causes blindness in millions of individuals.

Results

We report that targeting GMP-AMP (cGAMP) synthase (cGAS) alleviates Alu RNA-induced immune responses and cytotoxicity in RPE. We find that the deletion of cGAS in RPE inhibits the Alu RNA-stimulated interferon production. cGAS deficiency also protects RPE from cell death triggered by Alu RNA. Importantly, two natural chemicals, epigallocatechin gallate (EGCG) and resveratrol (RSVL), are effective in suppressing the immunogenic and cytotoxic effect of Alu RNA in RPE.

Conclusions

Our findings further demonstrate the crucial role of cGAS in the Alu RNA-induced RPE damage and present EGCG and RSVL as potential therapies for AMD and other RPE degeneration-related conditions.

Transcription factor Foxp1 is essential for the induction of choroidal neovascularization

Background

The exudative form of age-related macular degeneration (AMD) is characterized by abnormal blood vessel growth, which is stimulated by vascular endothelial growth factor (VEGF) released from retinal pigment epithelium (RPE). The angiogenic behaviors of vascular endothelial cells in vitro depend on forkhead box protein P1 (Foxp1), a transcription repressor widely expressed in human and murine tissues during development. In this study, we aimed to determine whether loss of Foxp1 affects laser-induced choroidal neovascularization (CNV) in mouse.

Methods

Eye-selective deletion of Foxp1 was obtained by crossing Foxp1^flox/flox with Six3-Cre mice. Laser photocoagulation was delivered to six- to eight-week-old mice to induce CNV. The expression of Foxp1 and Cre was determined by immunofluorescence in cryostat sections of the eyes. Fundus fluorescein angiography (FFA), optical coherence tomography (OCT), and B4 isolectin staining were applied to analyze the leakage, bulge height, and area of CNV lesions, respectively. RPE-choroid tissues were isolated for the determination of VEGF and pigment epithelium derived factor (PEDF) by Western blotting.

Results

Foxp1 was expressed in retinal ganglion cells, RPE, and the choroidal endothelial cells. Laser photocoagulation increased the number of Foxp1⁺-endothelial cells and induced CNV. Six3-Cre reduced Foxp1 expression in RPE but not the endothelium, leading to a lower level of VEGF in the RPE-choroid. Foxp1 knockout inhibited pathological angiogenesis and vascular leakage of the laser-induced CNV lesions.

Conclusions

Foxp1 regulates the expression of VEGF in the RPE, and inhibition of Foxp1 could potentially be a novel strategy for the prevention and therapy of neovascularization related to AMD.

Melanin-like Nanoparticles as an Alternative to Natural Melanin in Retinal Pigment Epithelium Cells and Their Therapeutic Effects against Age-Related Macular Degeneration

Melanin is a natural pigment that is widely distributed in many parts of the human body, such as the skin and retinal pigment epithelium (RPE) in eyes. In contrast to skin melanin, which is being constantly synthesized by the epidermal melanocytes, melanin in the RPE does not regenerate. Melanin is known to function as a potential radical scavenger and photoprotective agent. However, the protective effects of melanin against oxidative stress decline with increasing age. This phenomenon has been correlated with the pathogenesis of age-related macular degeneration (AMD). To increase the potential antioxidant and photoprotective characteristics of melanin, we designed a therapeutic strategy for replenishment of melanin using PEGylated synthetic melanin-like nanoparticles (MNPs) in the RPE for the treatment of AMD. We performed experiments using AMD-like cellular and mouse models and demonstrated that MNPs are biocompatible and selectively target reactive oxygen species (ROS) with powerful antioxidant properties. MNPs can traffic and accumulate in the RPE and are exclusively located in cytosol, but not the nucleus and mitochondria of the cells, for at least 3 months after a single-dose intravitreal injection. Our findings demonstrate that MNPs are able to substitute for natural melanin in the RPE and suggest the potential efficacy of MNPs as a natural radical scavenger against oxidative stress in ROS-related diseases, such as AMD.

Brolucizumab Intravitreal Injection in Macular Neovascularization Type 1: VA, SD-OCT, and OCTA Parameter Changes during a 16-Week Follow-Up

INTRODUCTION

The aim of this study was to assess early anatomical and functional changes after brolucizumab intravitreal injection (BIVI) in patients with age-related macular degeneration (AMD) and macular neovascularization type 1 (MNV1).

METHODS

A total of 24 eyes of 24 patients suffering from naïve AMD with MNV1 candidates to BIVI as per label with q12/q8 dosing regimen after the loading dose were enrolled in this prospective study. Main outcome measures during a 16-week follow-up period included changes in best corrected visual acuity (BCVA), central macular thickness (CMT), subfoveal subretinal fluid (SSRF) thickness (SSRFT), subfoveal sub-retinal pigment epithelium (RPE) fluid thickness (SSRPEFT), subfoveal choroidal thickness (SFCT), and pigment epithelial detachment (PED) maximum height (PED-MH). In addition, MNV1 flow area; percentages of eyes with intraretinal fluid (IRF), subretinal fluid, and sub-RPE fluid at different time points; and percentages of eyes candidates to a q8 or q12 injection interval after disease activity assessment at week 16 were evaluated.

RESULTS

BCVA improved significantly from baseline (T0) to week 12 (T3) (p = 0.028). CMT showed a significant reduction from 456 ± 123 µm at T0 to 265 ± 85 µm at T3 (p < 0.001). SSRFT and SSRPEFT reduced significantly as well (p < 0.001 and p = 0.049, respectively). PED-MH and SFCT reduced significantly at the different time points (p = 0.020; p = 0.006, respectively). IRF presence changed significantly from 41.7% of eyes at T0 to 20.8% at T3 (p = 0.045). SSRF reduced significantly during follow-up, being present in 62.5% of eyes at T0 and 4.2% of eyes at T3 (p < 0.001). Subfoveal sub-RPE fluid decreased significantly during time, being present in 20.8% of eyes at T0 and 0% at T3 (p = 0.013). Most of the eyes (18 eyes, 75%) at week 16 after disease activity assessment were shifted in the q12 interval, and only a minority of eyes shifted in a q8 interval (6 eyes, 25%).

CONCLUSION

Brolucizumab is efficient in AMD patients with MNV1 by reducing all retinal fluids during the loading phase and shows reduction of macular thickness, choroidal thickness, and PED height. Most eyes at disease activity assessment (75%) fall into 12-week interval and the minority (25%) into the 8-week interval.

Brolucizumab for the Treatment of Degenerative Macular Conditions: A Review of Clinical Studies

Age-related macular degeneration (AMD), diabetic retinopathy and retinal vein occlusion represent some of the commonest degenerative conditions that lead to severe vision impairment in the developed countries. The gold standard treatment of complications associated with these conditions is the intravitreal administration of anti-vascular endothelial growth factor (VEGF) agents. Brolucizumab is a newly developed, humanised, single-chain fragment of a monoclonal antibody binding all VEGF-A isoforms, which was recently approved for the treatment of neovascular AMD. Intravitreal brolucizumab promises to reduce treatment burden for nAMD patients by achieving comparable therapeutic outcomes with fewer clinic visits. Promising also appears its use for the treatment of more challenging maculopathies like diabetic macular oedema (DMO). The aim of this review is to describe the special pharmacological properties of brolucizumab and display the outcomes of the most important clinical trials and real-world studies regarding its efficacy and safety for the management of degenerative macular disorders.

Novel Treatments for Age-Related Macular Degeneration: A Review of Clinical Advances in Sustained Drug Delivery Systems

In recent years, the number of patients with ocular diseases is increasing as a consequence of population aging. Among them, one of the most common is the age-related macular degeneration (AMD), a condition that leads to vision loss if it is not treated. AMD is a multifactorial disorder with two advanced forms, dry and neovascular AMD. Currently, although there is no approved therapy that significantly impacts dry AMD progression, several pharmacologic therapies exist for neovascular AMD. Notwithstanding, evidence suggests a suboptimal result in a high number of patients receiving these therapeutic options. Consequently, finding effective strategies is not only a still unmet medical need in dry AMD but also in neovascular AMD. This underlines the need for new drug delivery technologies that can improve the pharmacological action and drug concentration at the target sites. In this regard, sustained drug delivery systems are presented as the most promising therapeutic options in AMD patients. This review summarized the pathogenesis and the current treatment options for AMD, focusing on the emerging ocular sustained drug delivery approaches undergoing clinical trials.

CD146 as a promising therapeutic target for retinal and choroidal neovascularization diseases

Blood vessel dysfunction causes several retinal diseases, including diabetic retinopathy, familial exudative vitreoretinopathy, macular degeneration and choroidal neovascularization in pathological myopia. Vascular endothelial growth factor (VEGF)-neutralizing proteins provide benefits in most of those diseases, yet unsolved haemorrhage and frequent intraocular injections still bothered patients. Here, we identified endothelial CD146 as a new target for retinal diseases. CD146 expression was activated in two ocular pathological angiogenesis models, a laser-induced choroid neovascularization model and an oxygen-induced retinopathy model. The absence of CD146 impaired hypoxia-induced cell migration and angiogenesis both in cell lines and animal model. Preventive or therapeutic treatment with anti-CD146 antibody AA98 significantly inhibited hypoxia-induced aberrant retinal angiogenesis in two retinal disease models. Mechanistically, under hypoxia condition, CD146 was involved in the activation of NFκB, Erk and Akt signalling pathways, which are partially independent of VEGF. Consistently, anti-CD146 therapy combined with anti-VEGF therapy showed enhanced impairment effect of hypoxia-induced angiogenesis in vitro and in vivo. Given the critical role of abnormal angiogenesis in retinal and choroidal diseases, our results provide novel insights into combinatorial therapy for neovascular fundus diseases.

Subretinal Implantation of Human Primary RPE Cells Cultured on Nanofibrous Membranes in Minipigs

Purpose: The development of primary human retinal pigmented epithelium (hRPE) for clinical transplantation purposes on biodegradable scaffolds is indispensable. We hereby report the results of the subretinal implantation of hRPE cells on nanofibrous membranes in minipigs. Methods: The hRPEs were collected from human cadaver donor eyes and cultivated on ultrathin nanofibrous carriers prepared via the electrospinning of poly(L-lactide-co-DL-lactide) (PDLLA). “Libechov” minipigs (12–36 months old) were used in the study, supported by preoperative tacrolimus immunosuppressive therapy. The subretinal implantation of the hRPE-nanofibrous carrier was conducted using general anesthesia via a custom-made injector during standard three-port 23-gauge vitrectomy, followed by silicone oil endotamponade. The observational period lasted 1, 2, 6 and 8 weeks, and included in vivo optical coherence tomography (OCT) of the retina, as well as post mortem immunohistochemistry using the following antibodies: HNAA and STEM121 (human cell markers); Bestrophin and CRALBP (hRPE cell markers); peanut agglutining (PNA) (cone photoreceptor marker); PKCα (rod bipolar marker); Vimentin, GFAP (macroglial markers); and Iba1 (microglial marker). Results: The hRPEs assumed cobblestone morphology, persistent pigmentation and measurable trans-epithelial electrical resistance on the nanofibrous PDLLA carrier. The surgical delivery of the implants in the subretinal space of the immunosuppressed minipigs was successfully achieved and monitored by fundus imaging and OCT. The implanted hRPEs were positive for HNAA and STEM121 and were located between the minipig’s neuroretina and RPE layers at week 2 post-implantation, which was gradually attenuated until week 8. The neuroretina over the implants showed rosette or hypertrophic reaction at week 6. The implanted cells expressed the typical RPE marker bestrophin throughout the whole observation period, and a gradual diminishing of the CRALBP expression in the area of implantation at week 8 post-implantation was observed. The transplanted hRPEs appeared not to form a confluent layer and were less capable of keeping the inner and outer retinal segments intact. The cone photoreceptors adjacent to the implant scaffold were unchanged initially, but underwent a gradual change in structure after hRPE implantation; the retina above and below the implant appeared relatively healthy. The glial reaction of the transplanted and host retina showed Vimentin and GFAP positivity from week 1 onward. Microglial activation appeared in the retinal area of the transplant early after the surgery, which seemed to move into the transplant area over time. Conclusions: The differentiated hRPEs can serve as an alternative cell source for RPE replacement in animal studies. These cells can be cultivated on nanofibrous PDLLA and implanted subretinally into minipigs using standard 23-gauge vitrectomy and implantation injector. The hRPE-laden scaffolds demonstrated relatively good incorporation into the host retina over an eight-week observation period, with some indication of a gliotic scar formation, and a likely neuroinflammatory response in the transplanted area despite the use of immunosuppression.

Incidence and Prevalence of Neovascular Age-Related Macular Degeneration in France between 2008 and 2018

Purpose

This study aimed to estimate the incidence and prevalence of neovascular age-related macular degeneration (nAMD) in the French population between 2008 and 2018.

Design

This was a retrospective, longitudinal population study using health care consumption data from the Système National des Données de Santé (SNDS; the French National Health Information Database), which covers approximately 99% of the French population.

Participants

We identified individuals treated for nAMD from the French population 50 years of age and older. Identification criteria were nAMD diagnosis or reimbursement of nAMD treatments (anti–vascular endothelial growth factor intravitreal injection or dynamic phototherapy with verteporfin). Exclusion criteria were high myopia, diagnosis of other retinal diseases, and other treatments for macular diseases (dexamethasone implant, laser therapy, etc.).

Methods

We calculated incidence and prevalence based on the age-matched general population in France. Adjustment for age and sex was also performed for incidence.

Main Outcome Measures

Incidence and prevalence of nAMD in the French population between 2008 and 2018.

Results

Between 2008 and 2018, we identified 342 961 patients with nAMD (67.5% women). Mean ± standard deviation age at nAMD diagnosis or first treatment increased from 78.8 ± 8.1 years in 2008 to 81.2 ± 7.9 years in 2018. In 2018, annual incidence was 0.149% and prevalence was 1.062% for the French population 50 years of age or older. Incidence was stable over the 10-year period. Annual incidence increased with age (0.223%, 0.380%, and 0.603% in those 60 years of age or older, 70 years of age or older, and 80 years of age or older, respectively), with similar trends for prevalence. No major differences were observed among the 14 regions of France for incidence or prevalence. Neovascular age-related macular degeneration incidence in 2018 was not impacted by the availability of primary or ophthalmology care in patients’ localities.

Conclusions

The LANDSCAPE study provides exhaustive nationwide data on incidence and prevalence of nAMD in France over a 10-year period.

A randomized, open-label, multicenter study of switching to brolucizumab with or without a loading dose for patients with suboptimal anatomically controlled neovascular age-related macular degeneration-the FALCON study

Background

Treatment initiation with brolucizumab, a new potent anti-vascular endothelial growth factor (VEGF) agent, is typically performed with three monthly injections (loading dose) and has been well studied in treatment-naïve patients. However, no clinical data are available yet on whether or not anti-VEGF pretreated patients also benefit from a loading dose. In the clinical setting, different heterogeneous treatment patterns are used as no clinical trial has addressed this so far in a head-to-head comparison. Therefore, the FALCON study is investigating whether patients with unsatisfactory response to previous anti-VEGF treatments benefit from a loading dose at the switch to brolucizumab treatment.

Methods

FALCON is a 52-week, two-arm, randomized, open-label, multicenter, multinational study in patients with residually active neovascular age-related macular degeneration (nAMD) who will be randomized 1:1 and started with brolucizumab 6 mg loading (three monthly loading doses) or brolucizumab 6 mg non-loading (one initial injection) and consecutive treatment every 12 weeks, respectively. The primary objective is to demonstrate non-inferiority of the non-loading vs. loading arm in mean change of best-corrected visual acuity (BCVA) from baseline to the mean value at week 40 to week 52. Secondary objectives include the assessment of anatomical outcomes, treatment intervals, safety and tolerability.

Results

FALCON will be the first study to assess treatment initiation with an anti-VEGF agent in a switch situation with or without loading dose in patients with nAMD.

Conclusions

The results will support the optimization of treatment of patients with previous unsatisfactory anti-VEGF response. Therefore, we expect to see an impact on current clinical practice which has been established for more than a decade.

Trial registration

Clinicaltrials.gov: NCT04679935, date of registration—22-Dec 2020; EUDRACT number: 2019–004763-53, date of registration—03 Dec 2019.

BROLUCIZUMAB - A NEW PLAYER IN THE FIELD OF ANTI-VEGF THERAPY OF NEOVASCULAR AGE-RELATED MACULAR DEGENERATION. A REVIEW

Vascular endothelial growth factor (VEGF) has been identified as a major promoter of the development of choroidal neovascularization in age-related macular degeneration. The development of choroidal neovascularization can be slowed by preventing the binding of vascular endothelial growth factor to cellular VEGF receptor-2 present on vascular endothelial cells, which represents the major proangiogenic stimulus. Advances in the development of anti-VEGF therapy have led to significant improvement in visual acuity outcomes in recent years that neovascular age-related macular degeneration can no longer be considered an incurable disease. Despite its many advantages, the current standard of care, which is the frequent application of VEGF blockers to the vitreous, is a significant burden on both the patient and the healthcare system. This review is aim on a new brolucizumab molecule (also known as RTH 258 or formerly ESBA 1008). The article focuses on the molecular aspects of the drug and an overview of the basic preclinical and clinical studies that were performed during drug development. Brolucizumab is a single chain fragment of a humanized monoclonal antibody with a molecular weight of 26 kDa that inhibits VEGF-A. Preclinical animal studies have shown good penetration of the molecule through the retina with minimal systemic exposure. The SEE study (phase 1/2) demonstrated safety and tolerability after drug administration. The OSPREY (phase 2) study demonstrated the same efficacy of brolucizumab on visual acuity in the 8-week dosing regimen compared to aflibercept. In the same study, patients were also pilot tested in a 12-week dosing regimen. The HAWK and HARRIER studies (phase 3) demonstrated the efficacy of the drug at a dose of 6 mg in a 12-week dosing schedule in 55.6 % and 51 % of patients, respectively.

Lipofuscin Granule Bisretinoid Oxidation in the Human Retinal Pigment Epithelium forms Cytotoxic Carbonyls

Age-related macular degeneration (AMD) is the primary cause of central blindness among the elderly. AMD is associated with progressive accumulation of lipofuscin granules in retinal pigment epithelium (RPE) cells. Lipofuscin contains bisretinoid fluorophores, which are photosensitizers and are phototoxic to RPE and neuroretinal cells. In the presence of oxygen, bisretinoids are also oxidized, forming various products, consisting primarily of aldehydes and ketones, which are also potentially cytotoxic. In a prior study, we identified that in AMD, bisretinoid oxidation products are increased in RPE lipofuscin granules. The purpose of the present study was to determine if these products were toxic to cellular structures. The physicochemical characteristics of bisretinoid oxidation products in lipofuscin, which were obtained from healthy donor eyes, were studied. Raman spectroscopy and time-of-flight secondary ion mass spectrometry (ToF–SIMS) analysis identified the presence of free-state aldehydes and ketones within the lipofuscin granules. Together, fluorescence spectroscopy, high-performance liquid chromatography, and mass spectrometry revealed that bisretinoid oxidation products have both hydrophilic and amphiphilic properties, allowing their diffusion through lipofuscin granule membrane into the RPE cell cytoplasm. These products contain cytotoxic carbonyls, which can modify cellular proteins and lipids. Therefore, bisretinoid oxidation products are a likely aggravating factor in the pathogenesis of AMD.

Sirolimus loaded chitosan functionalized poly (lactic-co-glycolic acid) (PLGA) nanoparticles for potential treatment of age-related macular degeneration

The usefulness of sirolimus (SIR) in the treatment of diseases that involve retinal degeneration like age-related macular degeneration (AMD) has been well documented. However, the problem still remains probably owing to the peculiar environment of the eye and/or unfavourable physiochemical profile of SIR. In the present work, we aimed to fabricate sirolimus loaded PLGA nanoparticles (SIR-PLGA-NP) and chitosan decorated PLGA nanoparticles (SIR-CH-PLGA-NP) to be administered via non-invasive subconjunctival route. Both the nanoparticles were characterized in terms of size, zeta potential, DSC, FTIR and XRD analysis. Quality by Design (QbD) approach was employed during the preparation of nanoparticles and the presence of chitosan coating was confirmed through thermogravimetric analysis and contact angle studies. Cationic polymer modification showed sustained in-vitro SIR release and enhanced ex-vivo scleral permeation and penetration. Further, SIR-CH-PLGA-NP revealed enhanced cellular uptake and thus, reduced lipopolysaccharide (LPS)-induced free-radicals generation by RAW 264.7 cells. The prepared nanoparticles were devoid of residual solvent and were found to be safe in HET-CAM analysis, RBCs damage analysis and histopathology studies. Moreover, high anti-angiogenic potential was observed in SIR-CH-PLGA-NP compared with SIR-PLGA-NP in chorioallantoic membrane (CAM) test. Overall, the current work opens up an avenue for further investigation of CH-PLGA-NP as SIR nanocarrier in the treatment of AMD.

Treat-and-extend regimens of anti-vascular endothelial growth factor therapy for retinal vein occlusions: a systematic review and meta-analysis

OBJECTIVE

To investigate treat-and-extend (T&E) regimens of anti-vascular endothelial growth factor (anti-VEGF) therapy for the treatment of macular oedema secondary to retinal vein occlusions (RVOs).

METHODS

Ovid MEDLINE, Ovid EMBASE and CENTRAL were searched on 25 February 2021. Randomized controlled trials, cohort studies, case-control studies and case series were included. The primary outcome was the change in Early Treatment Diabetic Retinopathy Score (ETDRS) letters from baseline. Conversions from Snellen to ETDRS letters were performed utilizing a published protocol. Secondary outcomes included improvement in retinal thickness from baseline, number of anti-VEGF injections and frequency of adverse events. Outcomes were examined at 12 and 24 months. Certainty of evidence was assessed utilizing GRADE (Grading of Recommendations Assessments, Development and Evaluations) guidelines.

RESULTS

Seven hundred eighty-six eyes from 16 studies were included. Meta-analysis demonstrated a mean improvement of 15.7 (95% CI: 13.3-18.0) ETDRS letters at 12 months. Central retinal thickness improved 269.7 μm (95% CI: 233.64-305.90) at 12 months. Injections were performed 8.1 (95% CI: 7.4-8.7) and 13.1 (95% CI: 9.4-16.8) times at 12 and 24 months respectively. Adverse events were infrequent across all studies. Grading of Recommendations Assessments, Development and Evaluations (GRADE) certainty of evidence was very low across all outcomes.

CONCLUSIONS

The results support the viability of T&E regimens for the treatment of macular oedema secondary to RVOs.

Engineered extracellular vesicles derived from primary M2 macrophages with anti-inflammatory and neuroprotective properties for the treatment of spinal cord injury

Background

Uncontrollable inflammation and nerve cell apoptosis are the most destructive pathological response after spinal cord injury (SCI). So, inflammation suppression combined with neuroprotection is one of the most promising strategies to treat SCI. Engineered extracellular vesicles with anti-inflammatory and neuroprotective properties are promising candidates for implementing these strategies for the treatment of SCI.

Results

By combining nerve growth factor (NGF) and curcumin (Cur), we prepared stable engineered extracellular vesicles of approximately 120 nm from primary M2 macrophages with anti-inflammatory and neuroprotective properties (Cur@EVs^−cl−NGF). Notably, NGF was coupled with EVs by matrix metalloproteinase 9 (MMP9)-a cleavable linker to release at the injured site accurately. Through targeted experiments, we found that these extracellular vesicles could actively and effectively accumulate at the injured site of SCI mice, which greatly improved the bioavailability of the drugs. Subsequently, Cur@EVs^−cl−NGF reached the injured site and could effectively inhibit the uncontrollable inflammatory response to protect the spinal cord from secondary damage; in addition, Cur@EVs^−cl−NGF could release NGF into the microenvironment in time to exert a neuroprotective effect against nerve cell damage.

Conclusions

A series of in vivo and in vitro experiments showed that the engineered extracellular vesicles significantly improved the microenvironment after injury and promoted the recovery of motor function after SCI. We provide a new method for inflammation suppression combined with neuroprotective strategies to treat SCI.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-021-01123-9.

Analysis of topical dosing and administration effects on ocular drug delivery in a human eyeball model using computational fluid dynamics

Predicting the spatial and temporal drug concentration distributions in the eyes is essential for quantitative analysis of the therapeutic effect and overdose issue via different topical administration strategies. To address such needs, an experimentally validated computational fluid dynamics (CFD) based virtual human eye model with physiologically realistic multiple ophthalmic compartments was developed to study the effect of administration frequency and interval on drug concentration distributions. Timolol was selected as the topical dosing drug for the numerical investigation of how administration strategy can influence drug transport and concentration distribution over time in the human eye. Administration frequencies employed in this study are 1-4 times per day, and the administration time intervals are Δt = 900 s, 1800 s, and 3600 s. Numerical results indicate that the administration frequency can significantly affect the temporal timolol concentration distributions in the ophthalmic compartments. More administrations per day can prolong the mediations at relatively high levels in all compartments. CFD simulation results also show that shorter administration intervals can help the medication maintain a relatively higher concentration during the initial hours. Longer administration intervals can provide a more stable medication concentration during the entire dosing time. Furthermore, numerical parametric analysis in this study indicates that the elimination rate in the aqueous humor plays a dominant role in affecting the drug concentrations in multiple ophthalmic compartments. However, it still needs additional clinical data to identify how much drugs can be transported into the cardiac and/or respiratory systems via blood circulation for side effect assessment.

Association of Reading Performance in Geographic Atrophy Secondary to Age-Related Macular Degeneration With Visual Function and Structural Biomarkers

Importance

As a disabling and frequent disease, geographic atrophy secondary to age-related macular degeneration (AMD) constitutes an important study subject. Emerging clinical trials require suitable end points. The characterization and validation of reading performance as a functional outcome parameter is warranted.

Objective

To prospectively evaluate reading performance in geographic atrophy and to assess its association with established visual function assessments and structural biomarkers.

Design, Setting, and Participants

The noninterventional, prospective natural history Directional Spread in Geographic Atrophy study included patients with geographic atrophy secondary to AMD who were recruited at the University Hospital in Bonn, Germany. Participants were enrolled from June 2013 to June 2016. Analysis began December 2019 and ended January 2021.

Main Outcomes and Measures

Reading acuity and reading speed were assessed using Radner charts. Longitudinal fundus autofluorescence and infrared reflectance images were semiautomatically annotated for geographic atrophy, followed by extraction of shape-descriptive variables. Linear mixed-effects models were applied to investigate the association of those variables with reading performance.

Results

A total of 150 eyes of 85 participants were included in this study (median [IQR] age, 77.9 [72.4-82.1] years; 51 women [60%]; 34 men [40%]). Reading performance was impaired with a median (IQR) monocular reading acuity of 0.9 (0.4-1.3) logarithm of the reading acuity determination and a reading speed of 52.8 (0-123) words per minute. In the multivariable cross-sectional analysis, best-corrected visual acuity, area of geographic atrophy in the central Early Treatment Diabetic Retinopathy Study (ETDRS) subfield, classification of noncenter vs center-involving geographic atrophy, and area of geographic atrophy in the inner-right ETDRS subfield showed strongest associations with reading acuity (cross-validated R2for reading acuity = 0.69). Regarding reading speed, the most relevant variables were best-corrected visual acuity, low-luminance visual acuity, area of geographic atrophy in the central ETDRS subfield, in the inner-right ETDRS subfield, and in the inner-upper ETDRS subfield (R2 for reading speed = 0.67). In the longitudinal analysis, a similar prediction accuracy for reading performance was determined (R2 for reading acuity = 0.73; R2 for reading speed = 0.70). Prediction accuracy did not improve when follow-up time was added as an independent variable. Binocular reading performance did not differ from reading performance in the better-seeing eye.

Conclusions and Relevance

The association of reading acuity and speed with visual functional and structural biomarkers supports the validity of reading performance as a meaningful end point in clinical trials. These findings suggest that measures in clinical and low-vision care for patients with geographic atrophy should focus primarily on the better-seeing eye.

Ocular Therapeutics and Molecular Delivery Strategies for Neovascular Age-Related Macular Degeneration (nAMD)

Age-related macular degeneration (AMD) is the leading cause of vision loss in geriatric population. Intravitreal (IVT) injections are popular clinical option. Biologics and small molecules offer efficacy but relatively shorter half-life after intravitreal injections. To address these challenges, numerous technologies and therapies are under development. Most of these strategies aim to reduce the frequency of injections, thereby increasing patient compliance and reducing patient-associated burden. Unlike IVT frequent injections, molecular therapies such as cell therapy and gene therapy offer restoration ability hence gained a lot of traction. The recent approval of ocular gene therapy for inherited disease offers new hope in this direction. However, until such breakthrough therapies are available to the majority of patients, antibody therapeutics will be on the shelf, continuing to provide therapeutic benefits. The present review aims to highlight the status of pre-clinical and clinical studies of neovascular AMD treatment modalities including Anti-VEGF therapy, upcoming bispecific antibodies, small molecules, port delivery systems, photodynamic therapy, radiation therapy, gene therapy, cell therapy, and combination therapies.

Family-based exome sequencing identifies rare coding variants in age-related macular degeneration

Genome-wide association studies (GWAS) have identified 52 independent variants at 34 genetic loci that are associated with age-related macular degeneration (AMD), the most common cause of incurable vision loss in the elderly worldwide. However, causal genes at the majority of these loci remain unknown. In this study, we performed whole exome sequencing of 264 individuals from 63 multiplex families with AMD and analyzed the data for rare protein-altering variants in candidate target genes at AMD-associated loci. Rare coding variants were identified in the CFH, PUS7, RXFP2, PHF12 and TACC2 genes in three or more families. In addition, we detected rare coding variants in the C9, SPEF2 and BCAR1 genes, which were previously suggested as likely causative genes at respective AMD susceptibility loci. Identification of rare variants in the CFH and C9 genes in our study validated previous reports of rare variants in complement pathway genes in AMD. We then extended our exome-wide analysis and identified rare protein-altering variants in 13 genes outside the AMD-GWAS loci in three or more families. Two of these genes, SCN10A and KIR2DL4, are of interest because variants in these genes also showed association with AMD in case-control cohorts, albeit not at the level of genome-wide significance. Our study presents the first large-scale, exome-wide analysis of rare variants in AMD. Further independent replications and molecular investigation of candidate target genes, reported here, would assist in gaining novel insights into mechanisms underlying AMD pathogenesis.

A Fully Human Monoclonal Antibody Targeting cKIT Is a Potent Inhibitor of Pathological Choroidal Neovascularization in Mice

Stem cell factor (SCF) and its receptor, cKIT, are novel regulators of pathological neovascularization in the eye, which suggests that inhibition of SCF/cKIT signaling may be a novel pharmacological strategy for treating neovascular age-related macular degeneration (AMD). This study evaluated the therapeutic potential of a newly developed fully human monoclonal antibody targeting cKIT, NN2101, in a murine model of neovascular AMD. In hypoxic human endothelial cells, NN2101 substantially inhibited the SCF-induced increase in angiogenesis and activation of the cKIT signaling pathway. In a murine model of neovascular AMD, intravitreal injection of NN2101 substantially inhibited the SCF/cKIT-mediated choroidal neovascularization (CNV), with efficacy comparable to aflibercept, a vascular endothelial growth factor inhibitor. A combined intravitreal injection of NN2101 and aflibercept resulted in an additive therapeutic effect on CNV. NN2101 neither caused ocular toxicity nor interfered with the early retinal vascular development in mice. Ocular pharmacokinetic analysis in rabbits indicated that NN2101 demonstrated a pharmacokinetic profile suitable for intravitreal injection. These findings provide the first evidence of the potential use of the anti-cKIT blocking antibody, NN2101, as an alternative or additive therapeutic for the treatment of neovascular AMD.