Comparative safety and tolerability of anti-VEGF therapy in age-related macular degeneration

Suprachoroidal Injection: A Novel Approach for Targeted Drug Delivery

Treating posterior segment and retinal diseases poses challenges due to the complex structures in the eye that act as robust barriers, limiting medication delivery and bioavailability. This necessitates frequent dosing, typically via eye drops or intravitreal injections, to manage diseases, often leading to side effects with long-term use. Suprachoroidal injection is a novel approach for targeted drug delivery to the posterior segment. The suprachoroidal space is the region between the sclera and the choroid and provides a potential route for minimally invasive medication delivery. Through a more targeted delivery to the posterior segment, this method offers advantages over other routes of administration, such as higher drug concentrations, increased bioavailability, and prolonged duration of action. Additionally, this approach minimizes the risk of corticosteroid-related adverse events such as cataracts and intraocular pressure elevation via compartmentalization. This review focuses on preclinical and clinical studies published between 2019 and 2023, highlighting the potential of suprachoroidal injection in treating a variety of posterior segment diseases. However, to fully harness its potential, more research is needed to address current challenges and limitations, such as the need for technological advancements, refinement of injection techniques, and consideration of cost and accessibility factors. Future studies exploring its use in conjunction with biotech products, gene therapies, and cell-based therapies can lead to personalized treatments that can revolutionize the field of ophthalmology.

Oxidative Stress and Antioxidants in Age-Related Macular Degeneration

Oxidative stress plays a crucial role in aging-related eye diseases, including age-related macular degeneration (AMD), cataracts, and glaucoma. With age, antioxidant reparative capacity decreases, and excess levels of reactive oxygen species produce oxidative damage in many ocular cell types underling age-related pathologies. In AMD, loss of central vision in the elderly is caused primarily by retinal pigment epithelium (RPE) dysfunction and degeneration and/or choroidal neovascularization that trigger malfunction and loss of photo-sensing photoreceptor cells. Along with various genetic and environmental factors that contribute to AMD, aging and age-related oxidative damage have critical involvement in AMD pathogenesis. To this end, dietary intake of antioxidants is a proven way to scavenge free radicals and to prevent or slow AMD progression. This review focuses on AMD and highlights the pathogenic role of oxidative stress in AMD from both clinical and experimental studies. The beneficial roles of antioxidants and dietary micronutrients in AMD are also summarized.

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.

Current and Future Anti-VEGF Agents for Neovascular Age-Related Macular Degeneration

Age-related macular degeneration (AMD) is the most common cause of legal blindness in developed countries. Neovascular (ie, wet) AMD is currently managed with intravitreal therapy. Traditional treatments (ie, bevacizumab, ranibizumab, aflibercept) provide high-efficacy therapy but can also require frequent dosing. Newer and future anti-VEGF therapies aim to decrease injection frequency through eitherlonger half life or port-delivery systems (brolucizumab, conbercept, KSI-301, ranibizumab). This review outlines current anti-VEGF treatments and ways by which their duration might be extended.

Safety and clinical effectiveness of intravitreal administration of bevacizumab (Lumiere®) in patients with neovascular age-related macular degeneration

The present study was an open-label, prospective, uncontrolled and multicenter clinical trial to investigate the safety and effectiveness of bevacizumab (Lumiere^®) administered by the intravitreal route for the treatment of neovascular age-related macular degeneration (nAMD). A total of 22 patients without previous treatment with anti-vascular endothelial growth factor were recruited. Monthly therapy with 1.25 mg intravitreal bevacizumab was applied. Adverse events (AE), visual acuity (VA) and central retinal thickness (CRT) were assessed at baseline, day 1 and day 28 after each injection. A total of 87 AEs were reported; most of them were not serious (96.6%), expected (65.5%) and occurred after the third injection (56.3%). The most frequent AE was 'conjunctival hemorrhage' (29.9% of AEs), attributed to the injection procedure. Treatment was not suspended due to safety reasons in any case. After six months, a statistically significant gain of +8.2 (SD±8.8) letters and a CRT reduction of -75.50 µm (SD±120.3) were achieved with unilateral therapy. VA improvement and CRT reduction were also achieved with bilateral therapy, although to a lesser extent. The results of the present study suggested that therapy with a minimum of 3 doses of bevacizumab over a 6-month period was well tolerated and resulted in a sustained response regarding VA improvement and CRT reduction from the beginning of therapy compared with the baseline value. The study protocol was registered at clinicaltrials.gov (ref. no. NCT03668054).

Reporting of Safety Events during Anti-VEGF Treatment: Pharmacovigilance in a Noninterventional Trial

Aim

The prospective, noninterventional OCEAN study assessed the safety of intravitreal ranibizumab injections for treatment of neovascular age-related macular degeneration, diabetic macular edema, and retinal vein occlusion under real-world conditions in Germany.

Methods

Adults receiving ≥1 ranibizumab (0.5 mg) injections were recruited by 369 ophthalmologists and followed for 24 months. Information on adverse events (AEs) was reported by the treating physician or detected by the data management team. Collected information included observed AE, AE start and end date, intensity, causal relationship, outcome, severity, suspected drug, and actions taken.

Results

2,687 AEs were reported for 1,176 of the 5,781 patients who had received a total of 32,621 injections: 27.4% nonserious AEs, 30.3% serious AEs, 27.3% nonserious adverse drug reactions (ADRs), and 15.0% serious ADRs. Most patients reported no AEs (79.7%) or only 1 AE (10.3%). AEs were most commonly reported in the Medical Dictionary for Regulatory Activities (MedDRA) System Organ Class (SOC) Eye disorders (9.4% of patients) and General disorders and administration site conditions (5.8%). The most frequent AEs by MedDRA preferred term (PT) were visual acuity reduced (3.5% of patients), intraocular pressure increased (2.5%), and drug ineffective (2.1%). AEs occurred most frequently after 3 or 4 injections (1,129 of 2,687 AEs). The proportion of AEs in the SOC Eye disorders decreased slightly with increasing number of injections, from 39.8% of events after 1 or 2 injections to 29.1% after 5 or more injections. Rates of the most frequently reported PTs did not show any consistent increase with increasing number of injections. A decrease in overall AE rates was observed over the study course.

Conclusions

The results did not raise any new safety concerns for ranibizumab. The findings allow conclusions to be drawn on how pharmacovigilance data can be collected even more effectively in real-world studies to facilitate discussion on benefit-risk ratio.

Ghost cell glaucoma after intravitreous injection of ranibizumab in proliferative diabetic retinopathy

Background

The development of ghost cell glaucoma in patients with proliferative diabetic retinopathy (PDR) after intravitreous injection (IV) was rare. Here we reported a series of patients with PDR who received Intravitreous Ranibizumab (IVR) and developed ghost cell glaucoma and analyzed the potential factors that might be related to the development of ghost cell glaucoma.

Methods

Retrospective case series study. The medical records of 71 consecutive eyes of 68 PDR patients who received vitrectomy after IVR from January 2015 to January 2017 were reviewed. The development of ghost cell glaucoma after IVR was recorded. Characteristics of enrolled patients were retrieved from their medical charts. Factors associated with ghost cell glaucoma were compared between eyes with the development of ghost cell glaucoma and eyes without the development of ghost cell glaucoma. Variables were further enrolled in a binary backward stepwise logistic regression model, and the model that had the lowest AIC was chosen.

Results

There were 8 out of 71 eyes of the PDR patients developed ghost cell glaucoma after they received IVR. The interval between detection of elevation of intraocular pressure (IOP) and IV ranged from 0 to 2 days. Among them, after IVR, there were two eyes had IOP greater than 30 mmHg within 30 min, four eyes showed normal IOP at 30 min, and then developed ghost cell glaucoma within 1 day, two eyes developed ghost cell glaucoma between 24 and 48 h. The mean IOP was 46.5 ± 8.0 mmHg. All patients gained normal IOP after vitrectomy without medicine for lowering IOP. The presence of ghost cell glaucoma was associated with tractional retinal detachment (RR = 4.60 [2.02 ~ 8.48], p = 0.004) and fibrovascular membrane involving disk (RR = -3.57 [− 7.59 ~ − 0.92], p = 0.03) (AIC = 39.23, AUC = 0.88) in a logistic regression model.

Conclusion

Attention to postoperative IOP should be paid to patients with PDR undergoing vitrectomy who receive a preoperative IV of anti-VEGF agents. PDR patients with tractional retinal detachment or fibrovasucular membrane involving optic disc are more likely to develop ghost cell glaucoma after IV.

Risk-based Algorithm-guided Treatment Protocol for the Management of Neovascular Age-related Macular Degeneration

Objectives

To assess outcomes of a risk-based algorithm-guided treatment protocol for neovascular age-related macular degeneration.

Materials and Methods

Two hundred and ten eyes of 184 patients managed with anti-vascular endothelial growth factor (anti-VEGF) agents according to a protocol consisting of one of three initial regimens depending on risk with at least 2 years of follow-up were retrospectively evaluated. The “short-term monthly injections” protocol was used for low-risk patients with low-risk lesions and good fellow-eye vision. Patients with low-risk lesions but without good fellow-eye vision, or those with good fellow-eye vision and high-risk lesions were managed according to the “short-term treat-and-extend (TREX)” protocol. The “extended TREX” protocol was for patients with high-risk lesions and low fellow-eye visual acuity.

Results

The initial treatment plan consisted of short-term monthly injections in 62 eyes (30%), the short-term TREX regimen in 120 eyes (57%), and the extended TREX regimen in 28 eyes (13%). Overall, 63% of cases met the criteria for cessation of treatment. Approximately 58% of these cases had recurrence, at a mean of 13 months. The mean change in VA from baseline was +9.0 letters at 12 months and +8.0 letters at 24 months. VA improved during a mean follow-up of 46.8±22 months, with a mean of 3.4±1.6 anti-VEGF injections per year.

Conclusion

The risk-based algorithm-guided treatment protocol yielded visual outcomes similar to those of the common alternative treatment and monitoring regimens, with a dramatically reduced number of injections, as required by the individual lesion and vision in the fellow eye.

HDAC inhibition in the cpfl1 mouse protects degenerating cone photoreceptors in vivo

Cone photoreceptor cell death as it occurs in certain hereditary retinal diseases is devastating, with the affected patients suffering from a loss of accurate and colour vision. Regrettably, these hereditary cone diseases are still untreatable to date. Thus, the identification of substances able to block or restrain cone cell death is of primary importance. We studied the neuroprotective effects of a histone deacetylase inhibitor, Trichostatin A (TSA), in a mouse model of inherited, primary cone degeneration (cpfl1). We show that HDAC inhibition protects cpfl1 cones in vitro, in retinal explant cultures. More importantly, in vivo, a single intravitreal TSA injection significantly increased cone survival for up to 16 days post-injection. In addition, the abnormal, incomplete cone migration pattern in the cpfl1 retina was significantly improved by HDAC inhibition. These findings suggest a crucial role for HDAC activity in primary cone degeneration and highlight a new avenue for future therapy developments for cone dystrophies and retinal diseases associated with impaired cone migration.

Optimizing Anti-VEGF Treatment Outcomes for Patients with Neovascular Age-Related Macular Degeneration

BACKGROUND

The introduction of anti-vascular endothelial growth factor (anti-VEGF) drugs to ophthalmology has revolutionized the treatment of neovascular age-related macular degeneration (nAMD). Despite this significant progress, gaps and challenges persist in the diagnosis of nAMD, initiation of treatment, and management of frequent intravitreal injections. Thus, nAMD remains a leading cause of blindness in the United States.

OBJECTIVE

To present current knowledge, evidence, and expert perspectives on anti-VEGF therapies in nAMD to support managed care professionals and providers in decision making and collaborative strategies to overcome barriers to optimize anti-VEGF treatment outcomes among nAMD patients.

SUMMARY

Three anti-VEGF therapies currently form the mainstay of treatment for nAMD, including 2 therapies approved by the FDA for treatment of nAMD (aflibercept and ranibizumab) and 1 therapy approved by the FDA for oncology indications and used off-label for treatment of nAMD (bevacizumab). In clinical trials, each of the 3 agents maintained visual acuity (VA) in approximately 90% or more of nAMD patients over 2 years. However, in long-term and real-world settings, significant gaps and challenges in diagnosis, treatment, and management pose barriers to achieving optimal outcomes for patients with nAMD. Many considerations, including individual patient characteristics, on-label versus off-label treatment, repackaging, and financial considerations, add to the complexity of nAMD decision making and management. Many factors may contribute to additional challenges leading to suboptimal long-term outcomes among nAMD patients, such as delays in diagnosis and/or treatment approval and initiation, individual patient response to different anti-VEGF therapies, lapses in physician regimentation of anti-VEGF injection and monitoring, and inadequate patient adherence to treatment and monitoring. These latter factors highlight the considerable logistical, emotional, and financial burdens of long-term, frequent intravitreal injections and the vital importance of personalized approaches to anti-VEGF treatment decision making and management for patients with nAMD. To address these challenges and reduce the number of yearly injections, studies have examined alternative dosing regimens, including extended fixed intervals, as needed, and treat-and-extend strategies in specific nAMD patient populations. New clinical evidence and insights into expert clinical practice discussed in this article can support managed care professionals in the key role they play in addressing challenges in nAMD treatment and management and optimizing patient outcomes through appropriate management of anti-VEGF treatment.

DISCLOSURES

PRIME Education is an independent medical education company and has been an accredited provider of continuing education for 23 years. There is no fee for this activity as it is sponsored by PRIME through an educational grant from Regeneron. All authors contributed to the writing and reviewing of the article. Wykoff reports consultancies/research grants from Alcon Laboratories, Genentech/Roche, Clearside, and Iconic Therapeutics; consultancies/honoraria, research grants, and speaker fees from Allergan and Regeneron; research grants from Allegro, Apellis, Aura, NEI, NIH, Novartis, OHR Pharmaceuticals, Ophthotech, pSivida, Roche, Santen, SciFluor, Tyrogenex; and consultancies for Alimera Sciences, Alnylam Pharmaceuticals, Bayer, DORC, ONL Therapeutics, Thrombogenics, and Valeant. Clark reports advisory board work, consultancies, research grants, and speaker fees from Genentech/Roche and Regeneron and consultancy for Bayer. Brill reports consultancies for Aries Pharma, Avella, BaroNova, Braeburn Pharmaceuticals, Cardinal Health, Endogastric Solutions, GeneNews, Halt Medical, Lumendi, Medtronic, Monteris Medical, Natera, Phosphorus, Rebiotix, Seno Medical, UCB, Vermillion, Echosens, and HAP Innovations. Brill is a shareholder in EndoChoice, GeneNews, SonarMD, and SynerZ and reports advisory board work with Nestle Health Sciences, Indivior Pharmaceuticals, Eli Lilly, Blue Earth Diagnostics, Bayer, and AstraZeneca. Nielson reports advisory board work/consultancy and research grants for Genentech/Roche; advisory board work and research grants from Regeneron; and research grants from Alcon and Ophthotech.

Resveratrol reverses the adverse effects of bevacizumab on cultured ARPE-19 cells

Age-related macular degeneration (AMD) and proliferative diabetic retinopathy (PDR) are one of the major causes of blindness caused by neo-vascular changes in the retina. Intravitreal anti-VEGF injections are widely used in the treatment of wet-AMD and PDR. A significant percentage of treated patients have complications of repeated injections. Resveratrol (RES) is a polyphenol phytoalexin with anti-oxidative, anti-inflammatory and anti-proliferative properties. Hence, we hypothesized that if RES is used in combination with bevacizumab (BEV, anti-VEGF), it could reverse the adverse effects that precipitate fibrotic changes, drusen formation, tractional retinal detachment and so on. Human retinal pigment epithelial cells were treated with various combinations of BEV and RES. There was partial reduction in secreted VEGF levels compared to untreated controls. Epithelial-mesenchymal transition was lower in BEV + RES treated cultures compared to BEV treated cultures. The proliferation status was similar in BEV + RES as well as BEV treated cultures both groups. Phagocytosis was enhanced in the presence of BEV + RES compared to BEV. Furthermore, we observed that notch signaling was involved in reversing the adverse effects of BEV. This study paves way for a combinatorial strategy to treat as well as prevent adverse effects of therapy in patients with wet AMD and PDR.

Evaluation of contrast sensitivity and other visual function outcomes in neovascular age-related macular degeneration patients after treatment switch to aflibercept from ranibizumab

Purpose

This study evaluated visual function and anatomic and vision-related quality-of-life outcomes in recalcitrant neovascular age-related macular degeneration (AMD) subjects switched to aflibercept (Eylea^®) from ranibizumab (Lucentis^®).

Methods

In a single-center study conducted in Barrie, ON, 40 patients with persistent fluid despite previous ranibizumab treatment were switched to aflibercept with 3 consecutive monthly doses. Main outcome measure was mean change from baseline to week 12 in Pelli–Robson contrast sensitivity (CS). Secondary outcomes were mean change in best corrected visual acuity (BCVA), central retinal thickness (CRT), and National Eye Institute 25-Item Visual Function Questionnaire (NEI VFQ-25) score. A two-sided paired t-test was used in the statistical data analysis to compare the means of continuous variables.

Results

Forty-nine eyes (baseline visual acuity [VA] >6/120) were evaluated. Ranibizumab injections (mean ± standard deviation [SD] 28.2±22.1 [range 3–86]) were administered prior to treatment switch. Mean CS improved from 1.32 at baseline to 1.40 log units at week 12. VA was stable throughout. Mean CRT decreased from 354 µm at baseline to 332 µm at week 12 (−22 µm, P=0.004). Twenty-six (65%) patients experienced an overall improvement in NEI VFQ-25 score. Interestingly, a correlation was observed between improvement in log CS and CRT change (P=0.000046).

Conclusion

Contrast sensitivity improved statistically and significantly, and CRT decreased from baseline to week 12 after a switch to aflibercept from ranibizumab. Analysis of CS as an independent outcome end point in neovascular AMD treatment switch studies may provide a more complete understanding of visual response.

Effects of intravitreally injected Fc fragment on rat eyes

PURPOSE

Anti-vascular endothelial growth factor (VEGF) drugs are used to treat neovascular eye diseases. Some of these drugs contain Fc fragments (Fc), but it is unknown how their mode of action is influenced by Fc. Therefore, this study investigated the effects of Fc on rat eyes after intravitreal injection.

METHODS

Eighteen Long-Evans rats were intravitreally injected with sterile, biotin-labeled rat Fc (9.1 μg in 5 μl PBS). For control, 5 μl PBS was injected in another nine rats. Animals were sacrificed between 1 and 3 days (group 1), 7 days (group 2), and 14 days (group 3) after injection. The right eyes were examined by electron microscopy (EM). The left eyes were stained by immunohistochemistry to investigate the distribution of Fc and the presence of macrophages.

RESULTS

After 1 day, Fc had penetrated into the anterior chamber and the retina up to the inner nuclear layer, and was located especially in retinal vessels. High numbers of infiltrating cells were present within the vitreous, around the ciliary body, anterior chamber and inside the retina 1-3 days after Fc injection (p < 0.02 group 1 vs. control). Immunohistochemistry and EM showed that they were macrophages or granulocytes in close association with Fc. Ultrastructurally, there were effects on the blood vessels such as thrombocyte activation and fibrin formation.

CONCLUSIONS

Biotin labeling is ideal for investigating the distribution of intravitreally injected proteins in ocular tissue. Fc fragments at a dose corresponding to their concentration in standard AMD treatments induced inflammation, and particularly the attraction of immune-competent cells. This may be associated with the risk of inflammation or endophthalmitis after anti-VEGF treatment, and needs further investigation.