The use of neuroprotective agents in treating geographic atrophy

ReCLAIM-2: A Randomized Phase II Clinical Trial Evaluating Elamipretide in Age-related Macular Degeneration, Geographic Atrophy Growth, Visual Function, and Ellipsoid Zone Preservation

Objective

This study evaluated the safety and efficacy of elamipretide in dry age-related macular degeneration (AMD) with noncentral geographic atrophy (GA).

Design

ReCLAIM-2 was a prospective, phase II, randomized, placebo-controlled, double-masked, multicenter trial (NCT03891875).

Subjects

Patients aged ≥55 years with ≥1 eye with dry AMD with GA were enrolled.

Methods

Administration of daily subcutaneous elamipretide 40 mg was investigated in subjects for 48 weeks followed by a 4-week follow-up period.

Main Outcome Measures

The primary efficacy end points were the mean change from baseline (BL) in low-luminance best-corrected visual acuity (LL BCVA) and the change in square root (Sqrt) converted GA area from BL as measured by OCT. Additional predefined end points included ellipsoid zone (EZ) integrity preservation assessment and categorical changes in LL BCVA. The primary safety end point was the incidence and severity of adverse events.

Results

Of the 176 patients randomized, there were 117 and 59 patients in the elamipretide and placebo groups, respectively. Although elamipretide did not meet statistical significance for the primary end points (mean change in LL BCVA and mean change in Sqrt converted GA area), elamipretide produced a 43% reduction in the mean progression from BL in the macular percentage of total EZ attenuation/loss (i.e., complete loss of EZ band; nominal P = 0.0034) and 47% reduction in the mean progression of macular percentage of partial EZ attenuation/degradation (i.e., EZ-retinal pigment endothelium thickness of ≤20 microns; nominal P = 0.0040) versus placebo at week 48. Elamipretide treatment was also associated with significantly more patients experiencing a ≥10 letter gain in LL BCVA versus placebo (14.6% vs. 2.1%; nominal P = 0.0404). Adverse events were reported in 86% of those receiving elamipretide and 71% of the placebo group with the most common events being injection site reactions (e.g., pruritus, injection site pain, bruising, and erythema).

Conclusions

While the primary end points were not met in this phase II study, elamipretide treatment was associated with a slowing of progressive EZ degradation/loss, a surrogate for photoreceptor damage. These findings have important clinical relevance since EZ attenuation/photoreceptor loss precedes and predicts the progressive pathological changes associated with vision loss and AMD. The EZ attenuation/loss end point will serve as the regulatory approved primary end point in the elamipretide phase III clinical development program.

Financial Disclosures

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

Safety Results for Geographic Atrophy Associated with Age-Related Macular Degeneration Using Subretinal Cord Blood Platelet-Rich Plasma

Purpose

To evaluate the safety of subretinal injection of cord blood platelet-rich plasma (CB-PRP) and its possible effect in eyes affected by geographic atrophy (GA) associated with dry age-related macular degeneration (d-AMD).

Design

Interventional, open-label study started in January 2021 with follow-up at 12 months (the Si.Cord Study). This study was a single-center, nonrandomized, sequential-assigned clinical trial conducted in Rome, Italy, at Fondazione Policlinico Universitario Agostino Gemelli IRCCS (ClinicalTrials.gov NCT04636853).

Participants

Thirteen patients (26 eyes) with bilateral d-AMD-related GA were enrolled. One eye from each patient (with more advanced GA) underwent CB-PRP treatment, and the fellow eye was considered the control. All patients participated in follow-up at 12 months.

Intervention

All 13 eyes received 23-gauge (G) vitrectomy and subretinal injection of CB-PRP using a 41-gauge needle.

Main Outcomes and Measures

Best-corrected visual acuity (BCVA) with ETDRS letters, central macular thickness using OCT, and atrophic area measured on en face OCT images were assessed at baseline, 1, 3, 6, and 12 months.

Results

The BCVA in the treated group was 34.46 ± 20.8 ETDRS at baseline, 40.84 ± 20.52 at 1 month, 40.07 ± 20.34 at 3 months, 39.38 ± 19.84 at 6 months, and 35.84 ± 18.38 at 12 months. In the untreated group, the BCVA was 53 ± 21.1 ETDRS letters at baseline, 51.54 ± 20.99 at 1 month, 46.62 ± 19.47 at 3 months, 46.85 ± 18.58 at 6 months, and 43.92 ± 17.97 at 12 months (2-way analysis of variance: interaction of treatment by eye or time, P = 0.084). Central macular thickness did not show a significant intereye difference at 12 months (P = 0.97). The atrophic geographic areas tended to increase in both treated and fellow eyes at 12 months (P < 0.0001). No inflammatory reaction, endophthalmitis, retinal detachment, uveitis, or other complications due to the subretinal injection of CB-PRP were observed during the follow-up.

Conclusions

Subretinal injection of CB-PRP could be safely used for d-AMD in its GA form. Despite its safety, a larger cohort of patients, and probably a new way of administration, will be needed to understand whether the CB-PRP could have a role in the GA treatment.

Financial Disclosures

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

Geographic atrophy progression secondary to age-related macular degeneration: Five years of follow-up

PURPOSE

To study the progression of geographic atrophy (GA) secondary to age-related macular degeneration over a five-year follow-up.

METHODS

Eyes with GA included to assess demographic data, yearly optical coherence tomography (OCT) findings and the GA growth rate on infra-red (IR) images.

RESULTS

A total of 41 eyes of 29 patients were included with a mean age of 81.76 ± 6.37 at baseline, and 65.51% were females. Over five years, there was a significant increase in the mean GA area from 8.44 ± 8.98 mm² to 13.32 ± 10.07 mm² (P < 0.001), with an annual growth rate of 1.14 ± 0.78 mm². The annual growth rates in females were slightly higher compared to males (1.29 ± 0.89 mm2 vs 0.96 ± 0.49 mm2, p = 0.569), and in smokers was slightly higher than non-smokers (1.35 ± 0.85 mm2 vs 0.94 ± 0.66 mm2, p = 0.100). Larger GA areas at the baseline showed higher GA progression in mm2 per year (P = 0.04). Smaller GA areas and fovea-spared GA at the baseline exhibited a larger percentage increase (P < 0.001 and P = 0.015, respectively). There was a lower GA progression rate in eyes with outer retinal tubulations (ORT) (P = 0.027), yet no significant correlation was found between GA progression and other OCT features.

CONCLUSIONS

Smaller, fovea-sparing GA eyes experienced a more substantial proportional increase over five years. Also, The presence of ORT was associated with a slower rate of GA progression. Additionally, we observed a trend of faster GA growth in smokers and female genders.

Geographic Atrophy in AMD: Prognostic Factors Based on Long-Term Follow-Up

INTRODUCTION

The aim of this large-scale long-term retrospective study was to show the enlargement rate (ER) of geographic atrophy (GA) in age-related macular degeneration (AMD), defined as complete retinal pigment epithelium and outer retinal atrophy (cRORA), to find predictors of progression in a clinical routine setting and to compare GA evaluation methods.

METHODS

All patients available in our database with follow-up of at least 24 months and cRORA in at least one eye, regardless of neovascular AMD being present, were included. SD-OCT and fundus autofluorescence (FAF) evaluations were performed according to a standardized protocol. The cRORA area ER, the cRORA square root area ER, the FAF GA area, and the condition of the outer retina (inner-/outer-segment [IS/OS] line and external limiting membrane [ELM] disruption scores) were determined.

RESULTS

204 eyes of 129 patients were included. Mean follow-up time was 4.2 ± 2.2 (range 2-10) years. 109 of 204 (53.4%) eyes were classified as MNV-associated GA in AMD (initially or during follow-up); 95 of 204 (46.6%) eyes were classified as pure GA in AMD. The primary lesion was unifocal in 146 (72%) eyes and multifocal in 58 (28%) eyes. A strong correlation was observed between the area of cRORA (SD-OCT) and the FAF GA area (r = 0.924; p < 0.001). Mean ER was 1.44 ± 1.2 mm2/year, mean square root ER 0.29 ± 0.19 mm/year. There was no significant difference in mean ER between eyes without (pure GA) and with intravitreal anti-VEGF injections (MNV-associated GA) (0.30 ± 0.19 mm/year vs. 0.28 ± 0.20 mm/year; p = 0.466). Eyes with multifocal atrophy pattern at baseline had a significantly higher mean ER compared to eyes with unifocal pattern (0.34 ± 0.19 mm/year vs. 0.27 ± 1.19 mm/year; p = 0.008). There were moderate significant correlations between ELM and IS/OS disruption scores and visual acuity at baseline, 5 and 7 years (all r values ca. -0.5; p < 0.001). In multivariate regression analysis, a multifocal cRORA pattern at baseline (p = 0.022) and a smaller baseline lesion size (p = 0.036) were associated with a higher mean ER.

CONCLUSION

SD-OCT-evaluated cRORA area might serve as a GA parameter comparable to traditional FAF measurement in clinical routine. The dispersion pattern and baseline lesion size might be predictors of ER, whereas anti-VEGF treatment seems not to be associated with ER.

Treatment and prevention of pathological mitochondrial dysfunction in retinal degeneration and in photoreceptor injury

Pathological deterioration of mitochondrial function is increasingly linked with multiple degenerative illnesses as a mediator of a wide range of neurologic and age-related chronic diseases, including those of genetic origin. Several of these diseases are rare, typically defined in the United States as an illness affecting fewer than 200,000 people in the U.S. population, or about one in 1600 individuals. Vision impairment due to mitochondrial dysfunction in the eye is a prominent feature evident in numerous primary mitochondrial diseases and is common to the pathophysiology of many of the familiar ophthalmic disorders, including age-related macular degeneration, diabetic retinopathy, glaucoma and retinopathy of prematurity - a collection of syndromes, diseases and disorders with significant unmet medical needs. Focusing on metabolic mitochondrial pathway mechanisms, including the possible roles of cuproptosis and ferroptosis in retinal mitochondrial dysfunction, we shed light on the potential of α-lipoyl-L-carnitine in treating eye diseases. α-Lipoyl-L-carnitine is a bioavailable mitochondria-targeting lipoic acid prodrug that has shown potential in protecting against retinal degeneration and photoreceptor cell loss in ophthalmic indications.

Fenretinide in Cancer and Neurological Disease: A Two-Face Janus Molecule

Recently, several chemotherapeutic drugs have been repositioned in neurological diseases, based on common biological backgrounds and the inverse comorbidity between cancer and neurodegenerative diseases. Fenretinide (all-trans-N-(4-hydroxyphenyl) retinamide, 4-HPR) is a synthetic derivative of all-trans-retinoic acid initially proposed in anticancer therapy for its antitumor effects combined with limited toxicity. Subsequently, fenretinide has been proposed for other diseases, for which it was not intentionally designed for, due to its ability to influence different biological pathways, providing a broad spectrum of pharmacological effects. Here, we review the most relevant preclinical and clinical findings from fenretinide and discuss its therapeutic role towards cancer and neurological diseases, highlighting the hormetic behavior of this pleiotropic molecule.

Pathophysiology of Age-Related Macular Degeneration: Implications for Treatment

Age-related macular degeneration (AMD) is a complex, multifactorial, progressive retinal disease that affects millions of people worldwide and has become the leading cause of visual impairment in developed countries. The disease etiopathogenesis is not understood fully, although many triggers and processes that lead to dysfunction and degeneration of the retinal pigment epithelium (RPE) have already been identified. Thus, the lack of cellular control of oxidative stress, altered proteostasis, dysfunction of lipid homeostasis, and mitochondrial dysfunction form an internal feedback loop that causes the RPE to fail and allows accumulation of abnormal misfolded proteins and abnormal lipids that will form drusen. An inadequate antioxidant response, deficits in autophagy mechanisms, and dysregulation of the extracellular matrix (ECM) help to increase the deposition of abnormal drusen material over time. The drusen then act as inflammatory centers that trigger chronic inflammation of the subretinal space in which microglia and recruited macrophages are also involved, and where the complement system is a key component. Choriocapillaris degeneration and nutritional influences are also classic elements recognized in the AMD pathophysiology. The genetic component of the disease is embodied in the recognition of the described risk or protective polymorphisms of some complement and ECM related genes (mainly CFH and ARMS2/HTRA1). Thus, carriers of the risk haplotype at ARMS2/HTRA1 have a higher risk of developing late AMD at a younger age. Finally, gut microbiota and epigenetics may play a role in modulating the progression to advanced AMD with the presence of local inflammatory conditions. Because of multiple implicated processes, different complex combinations of treatments will probably be the best option to obtain the best visual results; they in turn will differ depending on the type and spectrum of disease affecting individual patients or the disease stage in each patient at a specific moment. This will undoubtedly lead to personalized medicine for control and hopefully find a future cure. This necessitates the continued unraveling of all the processes involved in the pathogenesis of AMD that must be understood to devise the combinations of treatments for different concurrent or subsequent problems.

Cell Death in AMD: The Rationale for Targeting Fas

Age-related macular degeneration (AMD) is a leading cause of irreversible blindness in the developed world. While great advances have been made in the treatment of the neovascular (“wet”) form of the disease, there is still a significant need for therapies that prevent the vision loss associated with the advanced forms of dry, atrophic AMD. In this atrophic form, retinal pigment epithelial (RPE) and photoreceptor cell death is the ultimate cause of vision loss. In this review, we summarize the cell death pathways and their relation to RPE and retinal cell death in AMD. We review the data that support targeting programmed cell death through inhibition of the Fas receptor as a novel approach to preserve these structures and that this effect results from inhibiting both canonical death pathway activation and reducing the associated inflammatory response. These data lay the groundwork for current clinical strategies targeting the Fas pathway in this devastating disease.