Characterizing the Journey of Geographic Atrophy Patients in Routine Ophthalmic Practice.

BACKGROUND AND OBJECTIVE: Geographic atrophy (GA) is a form of late-stage age-related macular degeneration (AMD). This study aims to characterize the journey of patients with GA in real-world ophthalmology practice. PATIENTS AND METHODS: This is a retrospective cohort study of 100 patients with GA and 100 with intermediate AMD (iAMD). RESULTS: Approximately one-third of GA patients' eyes had GA at the time of their initial AMD diagnosis, and nearly half of the iAMD patients' eyes had iAMD at that time. When holding confounders constant, GA patients experienced significantly worse visual acuity outcomes, and a significantly higher proportion required referrals for low vision evaluation, needed assistance for activities of daily living, failed to meet driving standards, and met criteria for legal blindness when compared to iAMD controls. CONCLUSIONS: Many patients have already progressed to GA by the time they receive an AMD diagnosis, emphasizing the importance of providing early detection and intervention, especially considering novel treatment options. [Ophthalmic Surg Lasers Imaging Retina 2024;55:204-210.].

Drug Approval for the Treatment of Geographic Atrophy: How We Got Here and Where We Need to Go.

PURPOSE: To discuss the clinical trial results leading to the US Food and Drug Administration (FDA) approval of anti-complement therapies for geographic atrophy (GA), perspectives on functional data from the GA clinical trials, and how lessons from the FDA approval may guide future directions for basic and clinical research in AMD. DESIGN: Selected literature review with analysis and perspective METHODS: We performed a targeted review of publicly available data from the clinical trials of pegcetacoplan and avacincaptad for the treatment of GA, as well as scientific literature on the natural history of GA and the genetics and basic science of complement in AMD. RESULTS: The approval of pegcetacoplan and avacincaptad was based on an anatomic endpoint of a reduction in the rate of GA expansion over time. However, functional data from 2 phase 3 clinical trials for each drug demonstrated no visual benefit to patients in the treatment groups. Review of the genetics of AMD and the basic science of the role for complement in AMD provides only modest support for targeting complement as treatment for GA expansion, and alternative molecular targets for GA treatment are therefore discussed. Reasons for the disconnect between anatomic and functional outcomes in the clinical trials of anti-complement therapies are discussed, providing insight to guide the configuration of future clinical studies for GA. CONCLUSION: Although avacincaptad and pegcetacoplan are our first FDA-approved treatments for GA, results from the clinical trials failed to show any functional improvement after 1 and 2 years, respectively, calling into question whether the drugs represent a "clinically relevant outcome." To improve the chances of more impactful therapies in the future, we provide basic-science rationale for pursuing non-complement targets; emphasize the importance of ongoing clinical research that more closely pins anatomic features of GA to functional outcomes; and provide suggestions for clinical endpoints for future clinical trials on GA.

Imaging geographic atrophy: integrating structure and function to better understand the effects of new treatments.

Geographic atrophy (GA) is an advanced and irreversible form of age-related macular degeneration (AMD). Chronic low grade inflammation is thought to act as an initiator of this degenerative process, resulting in loss of photoreceptors (PRs), retinal pigment epithelium (RPE) and the underlying choriocapillaris. This review examined the challenges of clinical trials to date which have sought to treat GA, with particular reference to the successful outcome of C3 complement inhibition. Currently, optical coherence tomography (OCT) seems to be the most suitable method to detect GA and monitor the effect of treatment. In addition, the merits of using novel anatomical endpoints in detecting GA expansion are discussed. Although best-corrected visual acuity is commonly used to monitor disease in GA, other tests to determine visual function are explored. Although not widely available, microperimetry enables quantification of retinal sensitivity (RS) and macular fixation behaviour related to fundus characteristics. There is a spatial correlation between OCT/fundus autofluorescence evaluation of PR damage outside the area of RPE loss and RS on microperimetry, showing important associations with visual function. Standardisation of testing by microperimetry is necessary to enable this modality to detect AMD progression. Artificial intelligence (AI) analysis has shown PR layers integrity precedes and exceeds GA loss. Loss of the ellipsoid zone has been recognised as a primary outcome parameter in therapeutic trials for GA. The integrity of the PR layers imaged by OCT at baseline has been shown to be an important prognostic indicator. AI has the potential to be invaluable in personalising care and justifying treatment intervention.

Long-term Follow-up of a Phase 1/2a Clinical Trial of a Stem Cell-Derived Bioengineered Retinal Pigment Epithelium Implant for Geographic Atrophy.

PURPOSE: To report long-term results from a phase 1/2a clinical trial assessment of a scaffold-based human embryonic stem cell-derived retinal pigmented epithelium (RPE) implant in patients with advanced geographic atrophy (GA). DESIGN: A single-arm, open-label phase 1/2a clinical trial approved by the United States Food and Drug Administration. PARTICIPANTS: Patients were 69-85 years of age at the time of enrollment and were legally blind in the treated eye (best-corrected visual acuity [BCVA], ≤ 20/200) as a result of GA involving the fovea. METHODS: The clinical trial enrolled 16 patients, 15 of whom underwent implantation successfully. The implant was administered to the worse-seeing eye with the use of a custom subretinal insertion device. The companion nonimplanted eye served as the control. The primary endpoint was at 1 year; thereafter, patients were followed up at least yearly. MAIN OUTCOME MEASURES: Safety was the primary endpoint of the study. The occurrence and frequency of adverse events (AEs) were determined by scheduled eye examinations, including measurement of BCVA and intraocular pressure and multimodal imaging. Serum antibody titers were collected to monitor systemic humoral immune responses to the implanted cells. RESULTS: At a median follow-up of 3 years, fundus photography revealed no migration of the implant. No unanticipated, severe, implant-related AEs occurred, and the most common anticipated severe AE (severe retinal hemorrhage) was eliminated in the second cohort (9 patients) through improved intraoperative hemostasis. Nonsevere, transient retinal hemorrhages were noted either during or after surgery in all patients as anticipated for a subretinal surgical procedure. Throughout the median 3-year follow-up, results show that implanted eyes were more likely to improve by > 5 letters of BCVA and were less likely to worsen by > 5 letters compared with nonimplanted eyes. CONCLUSIONS: This report details the long-term follow-up of patients with GA to receive a scaffold-based stem cell-derived bioengineered RPE implant. Results show that the implant, at a median 3-year follow-up, is safe and well tolerated in patients with advanced dry age-related macular degeneration. The safety profile, along with the early indication of efficacy, warrants further clinical evaluation of this novel approach for the treatment of GA. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

CHOROIDAL VASCULARITY INDEX IS ASSOCIATED WITH GEOGRAPHIC ATROPHY PROGRESSION.

PURPOSE: To investigate the correlation between choroidal vascularity index and the enlargement of geographic atrophy (GA) lesion secondary to age-related macular degeneration during the 2-year follow-up. METHODS: In this longitudinal observational study, 26 eyes (26 patients, mean age 75.7 ± 8.8 years) affected by GA were included. Choroidal vascularity index was calculated in the subfoveal 3000-µm area. The main outcome measure included correlation analysis between baseline choroidal vascularity index and the rate of GA enlargement. RESULTS: During the 2-year follow-up, the mean GA area increased from 6.99 ± 5.28 mm2 to 10.69 ± 6.61 mm2(P < 0.001), accounting for a growth rate of 0.35 ± 0.20 and 0.31 ± 0.17 mm/year after the square root transformation in the first and second year of follow-up, respectively. Stromal choroidal area significantly decreased during the 2-year follow-up (P = 0.002). Interestingly, there was a significant correlation between the baseline choroidal vascularity index and the rate of GA enlargement (r=-0.432, P = 0.027) and between stromal choroidal area and the rate of GA enlargement (r = 0.422, P = 0.032). No other significant relationship was disclosed among choroidal parameters with the rate of GA enlargement. CONCLUSION: Choroidal vascularity index impairment is strictly related to the rate of GA enlargement during the 1-year and 2-year follow-up in patients affected by GA. For this reason, choroidal vascularity index could be considered a predictor of GA progression in the clinical setting, and it could be considered as a new potential biomarker in the efficacy evaluation of new GA interventions.

Geographic Atrophy Progression Is Associated With Choriocapillaris Flow Deficits Measured With Optical Coherence Tomographic Angiography.

Purpose: The purpose of this study was to assess the associations between baseline choriocapillaris (CC) flow deficits and geographic atrophy (GA) progression. Methods: In this prospective cohort study, patients with GA underwent 3 × 3-mm macular spectral-domain optical coherence tomographic angiography (OCTA) at baseline and follow-up visits. Annual GA enlargement rate was defined as change of square root of GA area in 12 months. Shadow areas due to iris, media opacity, retinal vessels, and drusen were excluded. CC vessel density (CC-VD) in non-GA areas was measured using a validated machine-learning-based algorithm. Low perfusion area (LPA) was defined as capillary density below the 0.1 percentile threshold of the same location of 40 normal healthy control eye. Focal perfusion loss (FPL) was defined as percentage of CC loss within LPA compared with normal controls. Results: Ten patients with GA were enrolled and followed for 26 months on average. At baseline, the mean GA area was 0.84 ± 0.70 mm2. The mean CC-VD was 44.5 ± 15.2%, the mean LPA was 4.29 ± 2.6 mm2, and the mean FPL was 50.4 ± 28.2%. The annual GA enlargement rate was significantly associated with baseline CC-VD (r = -0.816, P = 0.004), LPA (r = 0.809, P = 0.005), and FPL (r = 0.800, P = 0.005), but not with age (r = 0.008, P = 0.98) and GA area (r = -0.362, P = 0.30). Conclusions: Baseline CC flow deficits were significantly associated with a faster GA enlargement over the course of 1 year, suggesting the choriocapillaris perfusion outside of a GA area may play a role in GA progression.

Localized Structural and Functional Deficits in a Nonhuman Primate Model of Outer Retinal Atrophy.

Purpose: Cell-based therapy development for geographic atrophy (GA) in age-related macular degeneration (AMD) is hampered by the paucity of models of localized photoreceptor and retinal pigment epithelium (RPE) degeneration. We aimed to characterize the structural and functional deficits in a laser-induced nonhuman primate model, including an analysis of the choroid. Methods: Macular laser photocoagulation was applied in four macaques. Fundus photography, optical coherence tomography (OCT), dye angiography, and OCT-angiography were conducted over 4.5 months, with histological correlation. Longitudinal changes in spatially resolved macular dysfunction were measured using multifocal electroretinography (MFERG). Results: Lesion features, depending on laser settings, included photoreceptor layer degeneration, inner retinal sparing, skip lesions, RPE elevation, and neovascularization. The intralesional choroid was degenerated. The normalized mean MFERG amplitude within lesions was consistently lower than control regions (0.94 ± 0.35 vs. 1.10 ± 0.27, P = 0.032 at month 1, 0.67 ± 0.22 vs. 0.83 ± 0.15, P = 0.0002 at month 2, and 0.97 ± 0.31 vs. 1.20 ± 0.21, P < 0.0001 at month 3.5). The intertest variation of mean MFERG amplitudes in rings 1 to 5 ranged from 13.0% to 26.0% in normal eyes. Conclusions: Laser application in this model caused localized outer retinal, RPE, and choriocapillaris loss. Localized dysfunction was apparent by MFERG in the first month after lesion induction. Correlative structure-function testing may be useful for research on the functional effects of stem cell-based therapy for GA. MFERG amplitude data should be interpreted in the context of relatively high intertest variability of the rings that correspond to the central macula. Sustained choroidal insufficiency may limit long-term subretinal graft viability in this model.

Local Progression Kinetics of Geographic Atrophy Depends Upon the Border Location.

Purpose: To assess the influence of lesion morphology and location on geographic atrophy (GA) growth rate. Methods: We manually delineated GA on color fundus photographs of 237 eyes in the Age-Related Eye Disease Study. We calculated local border expansion rate (BER) as the linear distance that a point on the GA border traveled over 1 year based on a Euclidean distance map. Eye-specific BER was defined as the mean local BER of all points on the GA border in an eye. The percentage area affected by GA was defined as the GA area divided by the total retinal area in the region. Results: GA enlarged 1.51 ± 1.96 mm2 in area and 0.13 ± 0.11 mm in distance over 1 year. The GA area growth rate (mm2/y) was associated with the baseline GA area (P < 0.001), perimeter (P < 0.001), lesion number (P < 0.001), and circularity index (P < 0.001); in contrast, eye-specific BER (mm/y) was not significantly associated with any of these factors. As the retinal eccentricity increased from 0 to 3.5 mm, the local BER increased from 0.10 to 0.24 mm/y (P < 0.001); in contrast, the percentage of area affected by GA decreased from 49.3% to 2.3%. Conclusions: Using distance-based measurements allows GA progression evaluation without significant confounding effects from baseline GA morphology. Local GA progression rates increased as a function of retinal eccentricity within the macula which is opposite of the trend for GA distribution, suggesting that GA initiation and enlargement may be mediated by different biological processes.

MACULAR HOLE ASSOCIATED WITH AGE-RELATED MACULAR DEGENERATION: Pathogenesis and Surgical Outcomes.

PURPOSE: To ascertain the pathogenesis of macular hole (MH) associated with age-related macular degeneration (AMD) and its surgical outcomes. METHODS: Patients with full-thickness MH associated with AMD (higher grades than intermediate) were enrolled. The mechanism of MH formation and closure rate after vitrectomy (surgical outcome) were determined using optical coherence tomography imaging. RESULTS: The mechanism of MH formation (35 eyes) associated with AMD was classified into four types: vitreomacular traction (42.9%), gradual retinal thinning caused by subretinal drusen or pigment epithelial detachment (22.9%), massive subretinal hemorrhage (20.0%), and combined (14.3%). In the 41 eyes that underwent vitrectomy, the logarithm of the minimum angle of resolution best-corrected visual acuity improved from 0.82 (0.10-2.30) preoperative to 0.69 (0.10-2.30) postoperative (P = 0.001). Successful closure of the MH was achieved in 33 eyes (80.5%) after vitrectomy. No significant association was observed between the closure rate of MH after vitrectomy and mechanism of MH formation (P = 0.083). CONCLUSION: The mechanism of MH formation associated with AMD was classified into four types and was not related to its surgical outcome. Considering visual improvement and surgical outcome after vitrectomy in our study, active surgical treatment can be considered for MH associated with AMD.

Assessment of macular function in patients with non-vascularized pigment epithelial detachment.

Non-vascularized pigment epithelial detachments (PED) are usually associated with dry age-related macular degeneration (AMD). In this study, we aimed to investigate the correlation between visual function and morphologic parameters. Seventeen eyes of eleven patients with non-vascularized AMD were enrolled. In addition to conventional optical coherence tomography (OCT), polarization-sensitive optical coherence tomography (PS-OCT) measurements were performed by evaluating the regularity of retinal pigment epithelium (RPE) entropy within the PED area. Retinal sensitivity was measured with MP-3 microperimetry, and retinal sensitivities within (RSin) and outside (RSout) the PED area were calculated. The relationship between OCT parameters and visual function was analyzed. As a result, there was a significant difference between the RSin and RSout (p < 0.001, Wilcoxon signed rank test). Moreover, RSin was significantly related to logMAR VA (p = 0.033, linear mixed model). The regularity of RPE entropy was significantly related to visual acuity and RSin (p = 0.00038, p = 0.031, linear mixed model), although neither the height nor area of PED correlated with visual function. Our results suggest that retinal sensitivity is significantly deteriorated within the PED area and RPE entropy measured with PS-OCT was closely related to visual function in eyes with non-vascularized PED.

IL-33trap-mediated IL-33 neutralization does not exacerbate choroidal neovascularization, but fails to protect against retinal degeneration in a dry age-related macular degeneration model.

The progressive and sight-threatening disease, age-related macular degeneration (AMD), is a growing public health concern due to ageing demographics, with the highest unmet medical need for the advanced stage of dry AMD, geographic atrophy. The pathogenesis underlying AMD is driven by a complex interplay of genetic and environmental factors. There is ample evidence that inflammation is strongly involved in AMD development. Interleukin-33 (IL-33) has been proposed to be critically involved in retinal degeneration, but a protective role in eye pathophysiology was also demonstrated. The current study investigated the therapeutic potential of IL-33trap, a novel IL-33-neutralizing biologic, in dry AMD/geographic atrophy and, based on controversial data regarding the protective versus detrimental functions of IL-33 in neovascularization, evaluated the risk of progression to wet AMD by IL-33 neutralization. Repeated intravitreal (IVT) injections of IL-33trap in the mouse laser-induced choroidal neovascularization model did not exacerbate neovascularization or leakage, while it significantly inhibited inflammatory cell infiltration in the retinal pigment epithelium and choroid. On the contrary, IVT treatment with IL-33trap significantly induced retinal inflammation and could not prevent retinopathy induction in the mouse sodium iodate (NaIO3) model. Overall, these data suggest a complex and dichotomous role of IL-33 in eye pathology and indicate that IL-33 neutralization is not able to prevent onset and progression of dry AMD pathogenesis.

Characterizing New-Onset Exudation in the Randomized Phase 2 FILLY Trial of Complement Inhibitor Pegcetacoplan for Geographic Atrophy.

OBJECTIVES: To evaluate clinical characteristics of eyes in which investigator-determined new-onset exudative age-related macular degeneration (eAMD) developed during the FILLY trial. DESIGN: Post hoc analysis of the phase 2 study of intravitreal pegcetacoplan in geographic atrophy (GA). SUBJECTS: Patients with GA secondary to age-related macular degeneration (AMD), n = 246. INTERVENTION: Either 15 mg intravitreal pegcetacoplan or sham given monthly or every other month for 12 months followed by a 6-month off-treatment period. MAIN OUTCOME MEASURES: Time of new eAMD onset in the study eye, history of eAMD in the fellow eye, presence of double-layer sign (DLS) on structural OCT in the study eye, changes in retinal anatomic features by structural OCT and fluorescein angiography (FA), and changes in visual acuity. RESULTS: Exudation was reported in 26 study eyes across treatment groups over 18 months. Mean time to eAMD diagnosis was 256 days (range, 31-555 days). Overall, a higher proportion of patients with a baseline history of eAMD in the fellow eye (P = 0.016) and a DLS in the study eye (P = 0.0001) demonstrated eAMD. Among study eyes in which eAMD developed, 18 of 26 (69%) had history of fellow-eye eAMD and 19 of 26 (73.1%) had DLS at baseline, compared with 76 of 217 study eyes (35%; P = 0.0007) and 70 of 215 study eyes (32.5%; P < 0.0001), respectively, in which eAMD did not develop. All 21 patients with structural OCT imaging at the time of eAMD diagnosis demonstrated subretinal fluid, intraretinal cysts, or both consistent with exudation. Among 17 patients who underwent FA at eAMD diagnosis, 10 showed detectable macular neovascularization (MNV), all occult lesions. Development of eAMD did not have an appreciable impact on visual acuity, and all patients responded to anti-vascular endothelial growth factor (VEGF) therapy. CONCLUSIONS: Intravitreal pegcetacoplan slowed the rate of GA growth and was associated with an unexpected dose-dependent increased incidence of eAMD with no temporal clustering of onset. Exudative AMD seemed to be associated with baseline eAMD in the contralateral eye and a DLS, suggestive of nonexudative MNV, in the study eye. The safety profile of pegcetacoplan was acceptable to proceed to phase 3 studies without adjustments to enrollment criteria.

Impact of Baseline Characteristics on Geographic Atrophy Progression in the FILLY Trial Evaluating the Complement C3 Inhibitor Pegcetacoplan.

PURPOSE: To evaluate the effect of select baseline characteristics on geographic atrophy (GA) progression in eyes receiving intravitreal pegcetacoplan or sham. DESIGN: Phase 2 multicenter, randomized, single-masked, sham-controlled trial. METHODS: Patients with GA received 15 mg pegcetacoplan monthly or every other month (EOM), or sham injection monthly or EOM for 12 months. Primary efficacy endpoint was change in GA lesion size (square root) from baseline. Post hoc analysis evaluated the effects of age; gender; lesion size, focality, and location (extrafoveal vs foveal); pseudodrusen status; best-corrected visual acuity (BCVA); and low-luminance deficit (LLD) on GA progression at Month 12. RESULTS: Of 246 randomized patients, 192 with 12-month data were included in this analysis. Overall mean (standard deviation) change in lesion size (mm) was 0.26 (0.17) (P < .01), 0.27 (0.27) (P < .05), and 0.36 (0.21) in the monthly pegcetacoplan (n = 67), EOM pegcetacoplan (n = 58), and sham (n = 67) groups, respectively. In univariate analysis, patients with extrafoveal lesions (P < .001), BCVA ≥20/60 (P = .001), and larger LLD (P = .002) had greater mean changes in lesion size. Multivariate analysis confirmed significant association of extrafoveal lesions (P = .001) and larger LLD (P = .023) with GA progression. Monthly and EOM pegcetacoplan significantly reduced progression (P < .05) when controlling for these risk factors. CONCLUSIONS: Extrafoveal lesions and larger LLD are potential risk factors for GA progression. Pegcetacoplan treatment significantly controlled GA progression even after accounting for these risk factors.

Normal- and Low-Luminance Automated Quantitative Contrast Sensitivity Assessment in Eyes With Age-Related Macular Degeneration.

PURPOSE: To assess the effectiveness of an active learning approach to measuring the contrast sensitivity function (CSF) in patients with various degrees of dry age-related macular degeneration (AMD) under multiple luminance conditions. DESIGN: Cross-sectional study. METHODS: Patients with AMD (26 intermediate AMD, 19 AMD with subretinal drusenoid deposits [SDD], 20 geographic atrophy [GA]) and 23 age-matched controls were tested with the Manifold Contrast Vision Meter (Adaptive Sensory Technology) and the qCSF algorithm, which applies active learning to estimate a model of the CSF's global shape. Testing was performed under conditions of standard and low luminance. For each AMD severity, the area under log CSF (AULCSF) and contrast sensitivities at individual spatial frequencies were calculated for analysis. Low-luminance deficits (LLDs) for visual acuity (VA) and AULCSF were calculated as the difference between standard and low luminance values. RESULTS: Progressive decreases in AULCSF were observed as disease severity increased. For standard luminance, pairwise comparisons revealed significant differences between control/intermediate AMD (P < .0005), control/SDD (P < .0005), control/GA (P < .0005), and intermediate AMD/GA (P < .005). Similarly, for low luminance, pairwise comparisons revealed significant differences between the controls and each disease group (all P < .0005), in addition to significant differences between intermediate AMD/SDD (P < .005), and intermediate AMD/GA (P < .005). No correlations were found between LLD VA and LLD AULCSF in any AMD groups. CONCLUSIONS: Contrast sensitivity measured via qCSF under both standard- and low-luminance conditions correlates with advancing stages of dry AMD. The interaction between luminance and contrast sensitivity appears to reflect a different aspect of visual function than the interaction between luminance and VA.

CORRELATION OF OUTER RETINAL TUBULATIONS AND CHORIOCAPILLARIS FLOW SIGNAL DEFICITS SURROUNDING GEOGRAPHIC ATROPHY.

PURPOSE: To evaluate and compare paralesional and perilesional choriocapillaris vascular impairment in eyes with geographic atrophy with and without outer retinal tubulations (ORT). METHODS: Using swept-source optical coherence tomography angiography, 6 × 6 mm scans of eyes with geographic atrophy with and without ORT were acquired. Choriocapillaris en-face flow and structural images were binarized, before flow signal deficit (FD) analysis in the paraatrophy zone (a 500-µm-wide band adjacent to the geographic atrophy) and the periatrophy zone (a 500-µm-wide band adjacent to the latter). RESULTS: Twenty-four eyes of 19 patients with ORT and 18 eyes of 15 patients without ORT were analyzed. With and without ORT, mean percental area of FD (%FD) was greater in para- than in periatrophy zone. The difference of %FD between para- and periatrophy zone (deltaFD) was lower in eyes with ORT (mean 1.8477%, 95% confidence interval 0.8607-2.8346) than without ORT (mean 4.0018%, 95% confidence interval 2.8622-5.1414). CONCLUSION: In eyes with geographic atrophy caused by non-neovascular age-related macular degeneration, smaller reductions in FDs were found between the para- and periatrophy zone in eyes with ORT. In both cohorts, the paraatrophy zone had more FD than the periatrophy zone.

Quantification of Key Retinal Features in Early and Late Age-Related Macular Degeneration Using Deep Learning.

PURPOSE: We sought to develop and validate a deep learning model for segmentation of 13 features associated with neovascular and atrophic age-related macular degeneration (AMD). DESIGN: Development and validation of a deep-learning model for feature segmentation. METHODS: Data for model development were obtained from 307 optical coherence tomography volumes. Eight experienced graders manually delineated all abnormalities in 2712 B-scans. A deep neural network was trained with these data to perform voxel-level segmentation of the 13 most common abnormalities (features). For evaluation, 112 B-scans from 112 patients with a diagnosis of neovascular AMD were annotated by 4 independent observers. The main outcome measures were Dice score, intraclass correlation coefficient, and free-response receiver operating characteristic curve. RESULTS: On 11 of 13 features, the model obtained a mean Dice score of 0.63 ± 0.15, compared with 0.61 ± 0.17 for the observers. The mean intraclass correlation coefficient for the model was 0.66 ± 0.22, compared with 0.62 ± 0.21 for the observers. Two features were not evaluated quantitatively because of a lack of data. Free-response receiver operating characteristic analysis demonstrated that the model scored similar or higher sensitivity per false positives compared with the observers. CONCLUSIONS: The quality of the automatic segmentation matches that of experienced graders for most features, exceeding human performance for some features. The quantified parameters provided by the model can be used in the current clinical routine and open possibilities for further research into treatment response outside clinical trials.

Correlations Between Choriocapillaris and Choroidal Measurements and the Growth of Geographic Atrophy Using Swept Source OCT Imaging.

PURPOSE: Correlations among enlargement rates (ERs) of geographic atrophy (GA) and choriocapillaris (CC) flow deficits (FDs), mean choroidal thickness (MCT), and choroidal vascularity index (CVI) were investigated using swept source-optical coherence tomography (SS-OCT) in age-related macular degeneration (AMD). DESIGN: A retrospective review of prospective, observational case series. METHODS: Eyes with GA from AMD were imaged with SS-OCT using 6 × 6-mm scan pattern. GA lesions were identified and measured using customized en face structural images, and annual square root ERs of GA were calculated. At baseline, choriocapillaris FDs from different regions outside the GA were measured, and MCT and CVI from the entire scan area were measured. All measurements were performed using previously published and validated algorithms. RESULTS: A total of 38 eyes from 27 patients were included. The CC FDs within each region around GA lesions were highly correlated with ERs of GA (all P < .005). CVI inside the GA region was correlated with the ERs (P = .03), whereas other choroidal measurements had no significant correlation with the ERs of GA (P > .06). CONCLUSIONS: Statistically significant correlations were found between the ERs of GA and CC percentage of FD (FD%) from the entire scan region outside the GA and not just the region immediately adjacent to the GA. These results suggest that abnormal CC perfusion throughout the macula contributes to disease progression in eyes with GA. CVI inside the GA region could also be a potential indicator for the growth of GA.

C5 Inhibitor Avacincaptad Pegol for Geographic Atrophy Due to Age-Related Macular Degeneration: A Randomized Pivotal Phase 2/3 Trial.

PURPOSE: The complement pathway may play a key role in the pathogenesis of age-related macular degeneration (AMD). The safety and efficacy of avacincaptad pegol (Zimura, IVERIC bio Inc, New York, NY), a C5 inhibitor, were assessed in participants with geographic atrophy (GA) secondary to AMD (GATHER1 Study). DESIGN: International, prospective, randomized, double-masked, sham-controlled, pivotal phase 2/3 clinical trial. PARTICIPANTS: A total of 286 participants with GA secondary to AMD. MAIN OUTCOME MEASURES: The primary efficacy endpoint was the mean rate of change in GA over 12 months measured by fundus autofluorescence (FAF) at 3 timepoints: baseline, month 6, and month 12. RESULTS: The reduction in the mean rate of GA growth (square root transformation) over 12 months was 27.4% (P = 0.0072) for the avacincaptad pegol 2 mg cohort and 27.8% (P = 0.0051) for the avacincaptad pegol 4 mg cohort compared with their corresponding sham cohorts. The results for both dose groups were statistically significant. Avacincaptad pegol was generally well tolerated after monthly administration over 12 months. There were no avacincaptad pegol-related adverse events (AEs) or inflammation. Further, there were no ocular serious AEs (SAEs) and no cases of endophthalmitis. The most frequent ocular AEs were related to the injection procedure. CONCLUSIONS: Intravitreal administration of avacincaptad pegol 2 mg and 4 mg led to a significant reduction of GA growth in eyes with AMD over a 12-month period. Because C5 inhibition theoretically preserves C3 activity, it may offer additional safety advantages. A second confirmatory pivotal clinical trial is underway to confirm the efficacy and safety of avacincaptad pegol in slowing the GA growth (GATHER2 Study).

Relationship of Topographic Distribution of Geographic Atrophy to Visual Acuity in Nonexudative Age-Related Macular Degeneration.

PURPOSE: To investigate the topographic distribution of geographic atrophy (GA) and to identify an anatomic endpoint that correlates with visual acuity (VA) in eyes with GA. DESIGN: Retrospective analysis of a multicenter, prospective, randomized controlled trial. PARTICIPANTS: The Age-Related Eye Disease Study participants with GA secondary to nonexudative age-related macular degeneration. METHODS: We manually delineated GA on 1654 fundus photographs of 365 eyes. We measured GA areas in 9 subfields on the Early Treatment Diabetic Retinopathy Study (ETDRS) grid and correlated them with VA via a mixed-effects model. We determined the optimal diameter for the central zone by varying the diameter from 0 to 10 mm until the highest r2 between GA area in the central zone and VA was achieved. We estimated the VA decline rate over 8 years using a linear mixed model. MAIN OUTCOME MEASURES: Geographic atrophy area in macular subfields and VA. RESULTS: The percentage of area affected by GA declined as a function of retinal eccentricity. GA area was higher in the temporal than the nasal region (1.30 ± 1.75 mm2 vs. 1.10 ± 1.62 mm2; P = 0.005) and in the superior than the inferior region (1.26 ± 1.73 mm2 vs. 1.03 ± 1.53 mm2; P < 0.001). Total GA area correlated poorly with VA (r2 = 0.07). Among GA areas in 9 subfields, only GA area in the central zone was associated independently with VA (P < 0.001). We determined 1 mm as the optimal diameter for the central zone in which GA area correlated best with VA (r2 = 0.45). On average, full GA coverage of the central 1-mm diameter zone corresponded to 34.8 letters' decline in VA. The VA decline rate was comparable between eyes with initial noncentral and central GA before GA covered the entire central 1-mm diameter zone (2.7 letters/year vs. 2.8 letters/year; P = 0.94). CONCLUSIONS: The prevalence of GA varies significantly across different macular regions. Although total GA area was associated poorly with VA, GA area in the central 1-mm diameter zone was correlated significantly with VA and may serve as a surrogate endpoint in clinical trials.