Growth Rate of Geographic Atrophy Secondary to Age-Related Macular Degeneration: A Meta-Analysis of Natural History Studies and Implications for Designing Future Trials

Progression Rate of Macular Retinal Pigment Epithelium Atrophy in Geographic Atrophy and Selected Inherited Retinal Dystrophies. A Systematic Review and Meta-Analysis

PURPOSE

To compare the macular retinal pigment epithelium (RPE) atrophy progression rate of selected degenerative and macular inherited retinal diseases (IRD).

DESIGN

Systematic review and meta-analysis.

METHODS

The protocol was registered on the PROSPERO database. Medline, Embase, Web of Science, Cochrane Central Register of Controlled Trials, and Google Scholar were searched up to September 15, 2023 for articles reporting the RPE atrophy growth rate in treatment-naïve eyes with geographic atrophy (GA), Stargardt disease (STGD1), Best disease, pseudoxanthoma elasticum (PXE), central areolar choroidal dystrophy (CACD), or pattern dystrophies with no previous or current macular neovascularization and a minimum follow-up time of 12 months. Meta-analyses determined mean RPE atrophy growth rates per disease, imaging modality (fundus autofluorescence [FAF], optical coherence tomography [OCT], or color fundus photography [CFP]) and metric (mm2/y or mm/y). The Newcastle-Ottawa scale and the Cochrane Risk-of-Bias tool assessed the risk of bias, and funnel plots were used to evaluate small-study effects.

RESULTS

From 4354 publications, 85 were included for meta-analysis: 69 studies (7815 eyes) on GA, 15 (1367 eyes) on STGD1, and one on both. Two studies on PXE were only eligible for review. No studies for other diseases met our eligibility criteria. The overall mean RPE atrophy growth rate for GA using FAF was 1.65 mm2/y (95% confidence interval [CI], 1.49-1.81) and 0.35 mm/y (95% CI, 0.28-0.41); using OCT, it was 1.46 mm2/y (95% CI, 1.28-1.64) and 0.34 mm/y (95% CI, 0.28-0.40); and on CFP it was 1.76 mm2/y (95% CI, 1.56-1.97) and 0.30 mm/y (95% CI, 0.28-0.31). For STGD1, using FAF it was 1.0 mm2/y (95% CI, 0.77-1.23) and 0.20 mm/y (95% CI, 0.17-0.23); on OCT, it was 0.80 mm2/y (95% CI, 0.72-0.88). No studies on STGD1 reported the growth rate with other imaging modalities or metrics. Growth rates in GA were faster than in STGD1 (p < .05). A larger baseline area of atrophy was generally associated with faster growth rates.

CONCLUSIONS

The RPE atrophy growth rate in GA is faster than in STGD1 but with great variation between studies and imaging modalities. Limited information was available for other macular IRD, suggesting further research is needed.

Detection of Geographic Atrophy Guided by Optical Coherence Tomography Sub-RPE Illumination Analysis in Patients With Intermediate Age-Related Macular Degeneration

Purpose: To evaluate the prevalence of geographic atrophy (GA) lesions in patients with a diagnosis of intermediate age-related macular degeneration (iAMD). Methods: A retrospective cross-sectional study was performed of patients with an International Classification of Diseases, 10th Revision, diagnosis of iAMD. The primary outcome was the percentage of eyes diagnosed with iAMD with an undocumented GA lesion identified on imaging. Multiple logistic regression was used to assess risk factors for atrophic lesions in patients with iAMD. Results: The study included 690 eyes of 428 patients with a diagnosis of iAMD. The mean age was 79.4 ± 8.4 years, and 66.3% of patients were women. Forty-nine eyes (7.1%) were graded as having GA lesions, and 34% of these eyes had foveal involvement. The mean visual acuity (VA) was better in patients without GA lesions than in patients with GA lesions (72.9 ± 12.9 letters vs 66.4 ± 13.8 letters; P = .001). No systemic comorbidity was associated with an increased risk of GA lesions in this cohort. Conclusions: A notable proportion of eyes diagnosed with iAMD by eye care providers had underlying GA lesions in this real-world cohort. The use of optical coherence tomography as an adjunctive tool helped increase the detection of early GA in these patients.

Photoreceptor-RPE loss ratio and fundus autofluorescence patterns as predictive factors for lesion progression in geographic atrophy

PURPOSE

To assess the impact of the ratio between photoreceptor (PR) loss and retinal pigment epithelium (RPE) loss on the progression of geographic atrophy (GA) and to explore correlations between abnormal fundus autofluorescence (FAF) patterns and the PR-RPE loss ratio.

DESIGN

Single-centre, retrospective case series.

METHODS

Multimodal images from 87 treatment-naïve patients with GA and a follow-up of 6-24 months were included. Geographic atrophy areas on FAF images and areas of PR-RPE loss on optical coherence tomography images at baseline were manually annotated, and FAF patterns were classified. The impact of these biomarkers on GA progression through month 24 as measured on FAF was evaluated using random slope and intercept models and Spearman correlation coefficients (ρ).

RESULTS

Mean square-root GA growth rate was 0.27 ± 0.28 mm per year. Mean PR-RPE loss ratio at baseline was 2.16 ± 1.75. Fundus autofluorescence patterns "diffuse" and "diffuse trickling" showed higher PR-RPE loss ratios at baseline and contributed statistically significantly to the slope of GA progression (p = 0.01 and p = 0.0019). Baseline GA lesion size was negatively correlated to PR-RPE loss ratios at baseline (ρ = -0.47, p < 0.0001). Overall, GA growth was higher in patients with higher PR-RPE loss ratios at baseline (ρ = 0.35, p = 0.0011), and the ratio's contribution to the slope of GA progression was statistically significant (p = 0.0001).

CONCLUSION

Eyes with higher PR-RPE loss ratios were more likely to exhibit FAF patterns "diffuse" and "diffuse trickling" and showed higher GA progression rates. Baseline characteristics derived from FAF and OCT images may thus offer information on lesion progression.

Pentosan Polysulfate Maculopathy: Final Outcomes from a 4-Year Prospective Study of Disease Progression after Drug Cessation

PURPOSE

To report the long-term disease course of pentosan polysulfate (PPS) maculopathy following drug cessation.

DESIGN

Single-institution, prospective case series.

METHODS

23 eyes of 12 participants seen at the Emory Eye Center with a diagnosis of PPS maculopathy were included in our study. Participants were enrolled between December 1, 2018, and December 1, 2019, and data were collected annually for four years.

MAIN OUTCOMES AND MEASURES

Changes in visual function and retinal structure were the primary outcomes measured. Visual function was assessed using Early Treatment Diabetic Retinopathy Study (ETDRS) best-corrected visual acuity (BCVA), ETDRS low-luminance visual acuity (LLVA), Minnesota low-vision reading (MNREAD) performance, contrast sensitivity, mesopic and scotopic microperimetry, and dark adaptometry. Patient reported outcomes were assessed with the National Eye Institute Visual Function Questionnaire (NEI-VFQ-39) and Low Luminance Questionnaire (LLQ). Structural outcomes included the presence of complete retinal pigment epithelium and outer retinal atrophy (cRORA), atrophic lesion size (in mm2), macular central subfield thickness (CST), and subfoveal choroidal thickness (SFCT).

RESULTS

Of the 12 participants, 11 (91.7%) were female, with a median age at enrollment of 58 years. The median ETDRS BCVA letter score at baseline was 83, with a median change of -5 letters over 4 years (P = 0.005). The median 4-year change in mesopic microperimetry average threshold and percent reduced threshold was -5.4 dB (P = 0.003) and 48.6% (P = 0.004), respectively. MNREAD performance (assessed at 2 and 4 years) declined across all measures, with a median maximum reading speed change of -21 words per minute (P = 0.007). NEI-VFQ-39 and LLQ composite scores significantly decreased over 4 years. At baseline, 9 eyes (39%) had macular cRORA. By the study's end, 5 of the remaining eyes (35.7%) developed new-onset cRORA. The median linearized growth rate of atrophic lesions was 0.23 mm/year. The median 4-year change of CST and SFCT was -7.0 µm (P = 0.055) and -22.0 µm (P = 0.610), respectively.

CONCLUSION

This prospective study demonstrates continued progression of broad-ranging functional and structural deficits in PPS maculopathy long after drug cessation. These findings should inform PPS prescribing patterns, patient counseling, and disease monitoring strategies.

Visual Loss in Geographic Atrophy: Learnings from the Lampalizumab Trials

PURPOSE

To assess the correlation of lesion growth rate and baseline factors, including foveal involvement and focality, on visual loss as measured by best-corrected visual acuity (BCVA) in patients with geographic atrophy (GA) secondary to age-related macular degeneration (AMD).

DESIGN

Retrospective analysis of the lampalizumab phase 3 (NCT02247479 and NCT02247531) and prospective observational (NCT02479386) trials.

PARTICIPANTS

Patients with bilateral GA.

METHODS

Monthly BCVA and fundus autofluorescence (FAF) at baseline and every 6 months for 2 years were analyzed. Baseline GA area from FAF images was correlated to baseline BCVA and change in BCVA. The lesion growth rate was calculated as the slope of a linear fit from all available GA area measurements of a patient. The association between GA growth rate quartiles and BCVA changes was assessed, subgrouped by GA foveal involvement or focality. Time-to-event analysis for BCVA loss of ≥5, ≥10, and ≥15 letters was performed. A Cox regression model adjusted for baseline factors was performed on these outcomes. Kaplan-Meier curves are provided for each baseline factor and GA growth rate.

MAIN OUTCOME MEASURES

Correlations of baseline BCVA, GA area, and growth rate with change in BCVA, and time to ≥5, ≥10, and ≥15-letter loss by foveal involvement or focality.

RESULTS

Best-corrected visual acuity and GA area at baseline did not correlate with BCVA change at any visit. Geographic atrophy growth rate showed a weak correlation with BCVA loss, which increased over time. The 2 highest GA growth rate quartiles had accelerated BCVA loss in eyes with subfoveal, unifocal lesions. Approximately 75%, 50%, and 25% of study eyes experienced a ≥5-, ≥10-, and ≥15-letter loss by 2 years, respectively.

CONCLUSIONS

Best-corrected visual acuity and GA area at baseline did not correlate with BCVA loss, but faster GA growth rates appeared to be associated with faster BCVA loss. Geographic atrophy foveal involvement and focality correlated with the rate of BCVA loss with subfoveal lesions at high risk of vision loss over time, especially when the GA lesion was unifocal.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

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.

Correlation Between Blue Fundus Autofluorescence and SD-OCT Measurements of Geographic Atrophy in Dry Age-Related Macular Degeneration

PURPOSE

To compare fundus autofluorescence (FAF) and spectral domain optical coherence tomography (OCT) measurements of geographic atrophy (GA) area and to analyze lesion area changes measured by spectral domain OCT in GATHER1.

DESIGN

An assessment reliability analysis using prospective, randomized, double-masked phase 2/3 clinical trial data.

METHODS

GATHER1 examined the efficacy and safety of avacincaptad pegol (ACP) for GA treatment. A post hoc analysis was performed to identify correlations between FAF- and OCT-based measurements of GA. GA area was measured on blue-light FAF images using semiautomatic segmentation software with support from OCT and near-infrared imaging. Machine-learning enhanced, multilayer segmentation of OCT scans were reviewed by human readers, and segmentation errors were corrected as needed. GA area was defined as total RPE loss on cross-sectional B scans. Time points included Months 0, 6, 12, and 18. Additionally, OCT-based GA-area changes between ACP and sham were analyzed.

RESULTS

There was a strong correlation (r = 0.93) between FAF and OCT GA area measurements that persisted through 18 months. Mean (SD) differences between OCT and FAF GA measurements were negligible: 0.11 mm2 (1.42) at Month 0, 0.03 mm2 (1.62) at Month 6, -0.17 mm2 (1.81) at Month 12, and -0.07 mm2 (1.78) at Month 18. OCT assessments of GA growth revealed a 30% and 27% reduction at Months 12 and 18, respectively, between ACP and sham, replicating FAF measurements from GATHER1.

CONCLUSIONS

The strong correlation between blue FAF and OCT measurements of GA area supports OCT as a reliable method to measure GA lesion area in clinical trials.

Topographic Clinical Insights From Deep Learning-Based Geographic Atrophy Progression Prediction

Purpose

To explore the contributions of fundus autofluorescence (FAF) topographic imaging features to the performance of convolutional neural network-based deep learning (DL) algorithms in predicting geographic atrophy (GA) growth rate.

Methods

Retrospective study with data from study eyes from three clinical trials (NCT02247479, NCT02247531, NCT02479386) in GA. The algorithm was initially trained with full FAF images, and its performance was considered benchmark. Ablation experiments investigated the contribution of imaging features to the performance of the algorithms. Three FAF image regions were defined relative to GA: Lesion, Rim, and Background. For No Lesion, No Rim, and No Background datasets, a single region of interest was removed at a time. For Lesion, Rim, and Background Shuffled datasets, individual region pixels were randomly shuffled. For Lesion, Rim, and Background Mask datasets, masks of the regions were used. A Convex Hull dataset was generated to evaluate the importance of lesion size. Squared Pearson correlation (r2) was used to compare the predictive performance of ablated datasets relative to the benchmark.

Results

The Rim region influenced r2 more than the other two regions in all experiments, indicating the most relevant contribution of this region to the performance of the algorithms. In addition, similar performance was observed for all regions when pixels were shuffled or only a mask was used, indicating intensity information was not independently informative without textural context.

Conclusions

These ablation experiments enabled topographic clinical insights on FAF images from a DL-based GA progression prediction algorithm.

Translational Relevance

Results from this study may lead to new insights on GA progression prediction.

Deep Learning-Based Prediction of Individual Geographic Atrophy Progression from a Single Baseline OCT

Objective

To identify the individual progression of geographic atrophy (GA) lesions from baseline OCT images of patients in routine clinical care.

Design

Clinical evaluation of a deep learning-based algorithm.

Subjects

One hundred eighty-four eyes of 100 consecutively enrolled patients.

Methods

OCT and fundus autofluorescence (FAF) images (both Spectralis, Heidelberg Engineering) of patients with GA secondary to age-related macular degeneration in routine clinical care were used for model validation. Fundus autofluorescence images were annotated manually by delineating the GA area by certified readers of the Vienna Reading Center. The annotated FAF images were anatomically registered in an automated manner to the corresponding OCT scans, resulting in 2-dimensional en face OCT annotations, which were taken as a reference for the model performance. A deep learning-based method for modeling the GA lesion growth over time from a single baseline OCT was evaluated. In addition, the ability of the algorithm to identify fast progressors for the top 10%, 15%, and 20% of GA growth rates was analyzed.

Main Outcome Measures

Dice similarity coefficient (DSC) and mean absolute error (MAE) between manual and predicted GA growth.

Results

The deep learning-based tool was able to reliably identify disease activity in GA using a standard OCT image taken at a single baseline time point. The mean DSC for the total GA region increased for the first 2 years of prediction (0.80-0.82). With increasing time intervals beyond 3 years, the DSC decreased slightly to a mean of 0.70. The MAE was low over the first year and with advancing time slowly increased, with mean values ranging from 0.25 mm to 0.69 mm for the total GA region prediction. The model achieved an area under the curve of 0.81, 0.79, and 0.77 for the identification of the top 10%, 15%, and 20% growth rates, respectively.

Conclusions

The proposed algorithm is capable of fully automated GA lesion growth prediction from a single baseline OCT in a time-continuous fashion in the form of en face maps. The results are a promising step toward clinical decision support tools for therapeutic dosing and guidance of patient management because the first treatment for GA has recently become available.

Financial Disclosures

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

Chorioretinal Atrophic Lesions Evolution in Patients with Quiescent Myopic Choroidal Neovascularization Followed for More Than 10 Years

Purpose

To evaluate the progression of chorioretinal atrophic areas associated with myopic choroidal neovascularization (CNV) in high myopic patients followed by a minimum period of 10 years.

Patients and Methods

Patients with myopic CNV lesions that achieved clinical and structural remissions over 10 years of follow-up were included. Medical records were reviewed for CNV characterization and treatment, best-corrected visual acuity at baseline (BCVA0), immediately after the last treatment (BCVA1) and at the latest visit (BCVA2). Fundus autofluorescence (FAF) was used to quantify the amount of atrophic area increase per year associated with the treated myopic CNV lesion. The first FAF performed after treatment suspension (FAF1) was compared with the most recent exam (FAF2).

Results

Thirty-six eyes from 36 patients were included. Mean total follow-up was 12.38 ± 2.68 years. Mean number of intravitreal injections (IVI) was 12.50 ± 12.40 and 25% of the eyes had previous treatment with photodynamic therapy (PDT). Mean improvement between BCVA0 and BCVA1 was 5.58 ± 15.98 letters (p < 0.001). However, a drop of 8.03 ± 12.25 letters was noticed between BCVA1 and BCVA2. FAF1 was 6.34 ± 4.92mm2 and increased to 9.88 ± 7.56mm2 (3.54 ± 3.79mm2 variation p < 0.001). The mean growth rate of the atrophic area was 0.89 ± 0.84mm2 per year. BCVA2 negatively correlated with FAF2 (k = -0.498, p = 0.002) being worse in patients with higher atrophic area growth rate (k = -0.341, p = 0.042). Eyes treated with PDT needed less IVI (5.89 ± 5.21 vs 14.70 ± 13.36, p = 0.008) but had larger FAF1 (9.80 ± 5.33 vs 5.19 ± 4.27, p = 0.013) and FAF2 (16.05 ± 7.10 vs 7.83 ± 6.63, p = 0.003). Hypothyroidism was associated with higher atrophy growth rate (1.55 ± 1.15 vs 0.73 ± 0.67, p = 0.016).

Conclusion

This research demonstrates the importance of chorioretinal atrophy progression after myopic CNV lesions regression and its impact on visual prognosis, reporting a mean yearly growth of 0.89 mm2 in atrophic areas. Previous treatment with PDT and hypothyroidism were identified as risk factors associated with larger atrophic areas and worse visual outcomes.

The effect of complement C3 or C5 inhibition on geographic atrophy secondary to age-related macular degeneration: A living systematic review and meta-analysis

With the introduction of therapies to treat geographic atrophy (GA), GA management in clinical practice is now possible. A living systematic review can provide access to timely and robust evidence synthesis. This review found that complement factor 3 and 5 (C3 and C5) inhibition compared to sham likely reduces change in square root GA area at 12 months and untransformed GA area at 24 months. There is likely little to no difference in the rate of systemic treatment-emergent adverse events compared to sham. C3 and C5 inhibition, however, likely does not improve best-corrected visual acuity (BCVA) at 12 months, and the evidence is uncertain regarding change in BCVA at 24 months. Higher rates of ocular treatment emergent adverse effects with complement inhibition occur at 12 months and likely at 24 months. Complement inhibition likely results in new onset neovascular age-related macular degeneration at 12 months. This living meta-analysis will continuously incorporate new evidence.

Geographic atrophy: pathophysiology and current therapeutic strategies

Geographic atrophy (GA) is an advanced stage of age-related macular degeneration (AMD) that leads to gradual and permanent vision loss. GA is characterized by the loss of photoreceptor cells and retinal pigment epithelium (RPE), leading to distinct atrophic patches in the macula, which tends to increase with time. Patients with geographic atrophy often experience a gradual and painless loss of central vision, resulting in difficulty reading, recognizing faces, or performing activities that require detailed vision. The primary risk factor for the development of geographic atrophy is advanced age; however, other risk factors, such as family history, smoking, and certain genetic variations, are also associated with AMD. Diagnosis is usually based on a comprehensive eye examination, including imaging tests such as fundus photography, optical coherence tomography (OCT), and fluorescein angiography. Numerous clinical trials are underway, targeting identified molecular pathways associated with GA that are promising. Recent approvals of Syfovre and Izervay by the FDA for the treatment of GA provide hope to affected patients. Administration of these drugs resulted in slowing the rate of progression of the disease. Though these products provide treatment benefits to the patients, they do not offer a cure for geographic atrophy and are limited in efficacy. Considering these safety concerns and limited treatment benefits, there is still a significant need for therapeutics with improved efficacy, safety profiles, and better patient compliance. This comprehensive review discusses pathophysiology, currently approved products, their limitations, and potential future treatment strategies for GA.

Avacincaptad pegol for geographic atrophy secondary to age-related macular degeneration: 18-month findings from the GATHER1 trial

BACKGROUND/OBJECTIVES

To assess the safety and efficacy of avacincaptad pegol (ACP), a C5 inhibitor, for geographic atrophy (GA) secondary to age-related macular degeneration (AMD) over an 18-month treatment course.

SUBJECTS/METHODS

This study was an international, prospective, randomized, double-masked, sham-controlled, phase 2/3 clinical trial that consisted of 2 parts. In part 1, 77 participants were randomized 1:1:1 to receive monthly intravitreal injections of ACP 1 mg, ACP 2 mg, or sham. In part 2, 209 participants were randomized 1:2:2 to receive monthly ACP 2 mg, ACP 4 mg, or sham. The mean rate of change of GA over 18 months was measured by fundus autofluorescence.

RESULTS

Compared with their respective sham cohorts, monthly ACP treatment reduced the mean GA growth (square root transformation) over 18 months by 28.1% (0.168 mm, 95% CI [0.066, 0.271]) for the 2 mg cohort and 30.0% (0.167 mm, 95% CI [0.062, 0.273]) for the 4 mg cohort. ACP treatment was generally well tolerated over 18 months, with most ocular adverse events (AEs) related to the injection procedure. Macular neovascularization (MNV) was more frequent in both 2 mg (11.9%) and 4 mg (15.7%) cohorts than their respective sham control groups (2.7% and 2.4%).

CONCLUSIONS

Over this 18-month study, ACP 2 mg and 4 mg showed continued reductions in the progression of GA growth compared to sham and continued to be generally well tolerated. A pivotal phase 3 GATHER2 trial is currently underway to support the efficacy and safety of ACP as a potential treatment for GA.

Onset and Progression of Persistent Choroidal Hypertransmission Defects in Intermediate Age-Related Macular Degeneration: A Novel Clinical Trial Endpoint

PURPOSE

The appearance and growth of persistent choroidal hypertransmission defects (hyperTDs) detected on en face swept-source optical coherence tomography (SS-OCT) images from eyes with intermediate age-related macular degeneration (iAMD) were studied to determine if they could serve as novel clinical trial endpoints.

DESIGN

Post hoc subgroup analysis of a prospective study.

METHODS

Subjects with iAMD underwent 6 × 6 mm SS-OCT angiography imaging at their baseline and follow-up visits. The drusen volumes were obtained using a validated SS-OCT algorithm. Two graders independently evaluated all en face structural images for the presence of persistent hyperTDs. The number and area of all hyperTDs along with drusen volume were obtained from all SS-OCT angiography scans. Eyes were censored from further follow-up once exudative AMD developed.

RESULTS

A total of 171 eyes from 121 patients with iAMD were included. Sixty-eight eyes developed at least 1 hyperTD. Within 1 year after developing a hyperTD, 25% of eyes developed new hyperTDs for an average of 0.44 additional hyperTDs. Over 2 years, as hyperTDs appeared, enlarged, and merged, the average area growth rate was 0.220 mm/yr using the square-root transformation strategy. A clinical trial design using the onset and enlargement of these hyperTDs for the study of disease progression in eyes with iAMD is proposed.

CONCLUSIONS

The appearance and growth of persistent choroidal hyperTDs in eyes with iAMD can be easily detected and measured using en face OCT imaging and can serve as novel clinical trial endpoints for the study of therapies that may slow disease progression from iAMD to late AMD.

Progression Dynamics of Early versus Later Stage Atrophic Lesions in Nonneovascular Age-Related Macular Degeneration Using Quantitative OCT Biomarker Segmentation

PURPOSE

To investigate the progression of geographic atrophy secondary to nonneovascular age-related macular degeneration in early and later stage lesions using artificial intelligence-based precision tools.

DESIGN

Retrospective analysis of an observational cohort study.

SUBJECTS

Seventy-four eyes of 49 patients with ≥ 1 complete retinal pigment epithelial and outer retinal atrophy (cRORA) lesion secondary to age-related macular degeneration were included. Patients were divided between recently developed cRORA and lesions with advanced disease status.

METHODS

Patients were prospectively imaged by spectral-domain OCT volume scans. The study period encompassed 18 months with scheduled visits every 6 months. Growth rates of recent cRORA-converted lesions were compared with lesions in an advanced disease status using mixed effect models.

MAIN OUTCOME MEASURES

The progression of retinal pigment epithelial loss (RPEL) was considered the primary end point. Secondary end points consisted of external limiting membrane disruption and ellipsoid zone loss. These pathognomonic imaging biomarkers were quantified using validated deep-learning algorithms. Further, the ellipsoid zone/RPEL ratio was analyzed in both study cohorts.

RESULTS

Mean (95% confidence interval [CI]) square root progression of recently converted lesions was 79.68 (95% CI, -77.14 to 236.49), 68.22 (95% CI, -101.21 to 237.65), and 84.825 (95% CI, -124.82 to 294.47) mm/half year for RPEL, external limiting membrane loss, and ellipsoid zone loss respectively. Mean square root progression of advanced lesions was 131.74 (95% CI, -22.57 to 286.05), 129.96 (95% CI, -36.67 to 296.59), and 116.84 (95% CI, -90.56 to 324.3) mm/half year for RPEL, external limiting membrane loss, and ellipsoid zone loss, respectively. RPEL (P = 0.038) and external limiting membrane disruption (P = 0.026) progression showed significant differences between the 2 study cohorts. Further recent converters had significantly (P < 0.001) higher ellipsoid zone/RPEL ratios at all time points compared with patients in an advanced disease status (1.71 95% CI, 1.12-2.28 vs. 1.14; 95% CI, 0.56-1.71).

CONCLUSION

Early cRORA lesions have slower growth rates in comparison to atrophic lesions in advanced disease stages. Differences in growth dynamics may play a crucial role in understanding the pathophysiology of nonneovascular age-related macular degeneration and for the interpretation of clinical trials in geographic atrophy. Individual disease monitoring using artificial intelligence-based quantification paves the way toward optimized geographic atrophy management.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Future perspectives for treating patients with geographic atrophy

PURPOSE

Geographic atrophy (GA) is a late-stage form of age-related macular degeneration (AMD) characterized by the expansion of atrophic lesions in the outer retina. There are currently no approved pharmacological treatments to prevent or slow the progression of GA. This review describes the progression and assessment of GA, predictive imaging features, and complement-targeting investigational drugs for GA.

METHODS

A literature search on GA was conducted.

RESULTS

Expansion of atrophic lesions in patients with GA is associated with a decline in several measures of visual function. GA lesion size has been moderately associated with measures obtained through microperimetry, whereas GA lesion size in the 1-mm diameter area centered on the fovea has been associated with visual acuity. Optical coherence tomography (OCT) can provide 3-dimensional quantitative assessment of atrophy and is useful for identifying early atrophy in GA. Features that have been found to predict the development of GA include certain drusen characteristics and pigmentary abnormalities. Specific OCT features, including hyper-reflective foci and OCT-reflective drusen substructures, have been associated with AMD disease progression. Lesion characteristics, including focality, regularity of shape, location, and perilesional fundus autofluorescence patterns, have been identified as predictors of faster GA lesion growth. Certain investigational complement-targeting drugs have shown efficacy in slowing the progression of GA.

CONCLUSION

GA is a progressive disease associated with irreversible vision loss. Therefore, the lack of treatment options presents a significant unmet need. OCT and drugs under investigation for GA are promising future tools for disease management.

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.

Geographic atrophy: Mechanism of disease, pathophysiology, and role of the complement system

Geographic atrophy (GA) is an advanced form of age-related macular degeneration (AMD), characterized by atrophic lesions that first start in the outer retina and progressively expand to cover the macula and the fovea, the center of the macula, leading to irreversible loss of vision over time. GA is distinct from wet or neovascular AMD (nAMD), the other form of advanced AMD. Neovascular AMD is characterized by new invading leaky blood vessels in the macula that can lead to acute vision loss. GA and nAMD may coexist in the same eye. The underlying pathophysiology of GA is complex and thought to involve chronic inflammation due to overactivation of the complement system that leads to the loss of photoreceptors, retinal pigment epithelium (RPE), and the underlying choriocapillaris. The disappearance of these structures appears as sharply demarcated atrophic lesions that are typical of GA. Researchers have reported about 1 million reported cases of GA in the United States, and about 160,000 cases occur per year. The most important risk factors for GA are increasing age and family history. Diagnosis of GA is usually made by using multimodal imaging techniques. Lesions associated with GA are highly heterogeneous, and the growth rate may differ from patient to patient. Despite the progressive nature of GA, the fovea may be spared until much later in the disease, thereby retaining central vision in patients. With time, atrophic lesions may progressively grow to involve the fovea, thereby severely impairing central vision. Vision loss can happen rapidly once the lesions reach the fovea. However, even without the involvement of the fovea, ongoing vision impairment impacting daily life may be present. Median time from GA not involving the center of the fovea (without subfoveal involvement) to GA with lesion boundary affecting the foveal center (subfoveal involvement) ranges from 1.4 to 2.5 years. GA can greatly impact patients' functioning and quality of life and limit their independence by interfering with activities of daily living, including difficulties with reading, driving, watching television, recognizing faces, and being unable to do household chores. No treatments have been available until intravitreal pegcetacoplan was recently approved by the US Food and Drug Administration for GA secondary to AMD. DISCLOSURES: Dr Bakri serves as a consultant to Apellis Pharmaceuticals, as well as AbbVie, Adverum, Eyepoint, iLumen, Iveric Bio, Genentech, Novartis, Outlook Therapeutics, Pixium, Regeneron, Roche, and Regenxbio. Drs Sharp, Luo, and Sarda are employees of Apellis Pharmaceuticals. Dr Bektas and Ms Khan are employees of RTI Health Solutions. Apellis developed and led the concept design of this publication, review and interpretation, approval, and decision to publish. This research was developed under a research contract between RTI Health Solutions and Apellis Pharmaceuticals and was funded by Apellis Pharmaceuticals. This supplement is to describe the disease of geographic atrophy and was funded by Apellis. Apellis Pharmaceuticals has developed Syfovre (pegcetacoplan), the first and only treatment for geographic atrophy.

Perspectives from clinical trials: is geographic atrophy one disease?

Geographic atrophy (GA) is currently an untreatable condition. Emerging evidence from recent clinical trials show that anti-complement therapy may be a successful treatment option. However, several trials in this therapy area have failed as well. This raises several questions. Firstly, does complement therapy work for all patients with GA? Secondly, is GA one disease? Can we assume that these failed clinical trials are due to ineffective interventions or are they due to flawed clinical trial designs, heterogeneity in GA progression rates or differences in study cohorts? In this article we try to answer these questions by providing an overview of the challenges of designing and interpreting outcomes of randomised controlled trials (RCTs) in GA. These include differing inclusion-exclusion criteria, heterogeneous progression rates of the disease, outcome choices and confounders.

Phase 1B study of the safety and tolerability of the mineralocorticoid fludrocortisone acetate in patients with geographical atrophy

Objective

To evaluate the safety and tolerability of a mineralocorticoid, in a single-dose intravitreal (IVT) injection of 1 mg/0.1 mL and 2 mg/0.1 mL fludrocortisone acetate (FCA) in subjects with geographical atrophy (GA) secondary to age-related macular degeneration.

Methods and Analysis

This phase 1b study was a two-part dose-escalation prospective study. Part 1 involved a single participant treated with 1 mg/0.1 mL and monitored up to 28 days before being reviewed by a safety review committee. Two subsequent participants were then dosed with the same dose. Part 2 involved a single participant dosed with 2 mg/0.1 mL and monitored up to 28 days when a further five participants were dosed. All participants were followed up for 6 months after baseline.

A full ophthalmic assessment was performed at study visits which included GA area, best-corrected visual acuity (BCVA), low-luminance BCVA (LL-BCVA) and intraocular pressure (IOP). Adverse events (AEs) were reported from the first dose of FCA until the end-of-study visit.

Results

There were no serious AEs (ocular or systemic) observed with IVT FCA at either 1 mg/0.1 mL or 2 mg/0.1 mL among nine participants. There was no evidence of increased IOP or cataract development.

Neither BCVA or LL-BCVA changed significantly in the study-eye over the follow-up period (p=0.28 and 0.38, respectively). Mean GA area increased in the study (0.5 mm², p=0.003) and fellow-eyes (0.62 mm², p=0.02) over 6 months. Differences between eyes were not significant (p=0.64), and at the lower end of population norms.

Conclusion

IVT FCA is clinically safe and well tolerated and did not increase IOP.

A hierarchical Bayesian entry time realignment method to study the long-term natural history of diseases

A major question in clinical science is how to study the natural course of a chronic disease from inception to end, which is challenging because it is impractical to follow patients over decades. Here, we developed BETR (Bayesian entry time realignment), a hierarchical Bayesian method for investigating the long-term natural history of diseases using data from patients followed over short durations. A simulation study shows that BETR outperforms an existing method that ignores patient-level variation in progression rates. BETR, when combined with a common Bayesian model comparison tool, can identify the correct disease progression function nearly 100% of the time, with high accuracy in estimating the individual disease durations and progression rates. Application of BETR in patients with geographic atrophy, a disease with a known natural history model, shows that it can identify the correct disease progression model. Applying BETR in patients with Huntington's disease demonstrates that the progression of motor symptoms follows a second order function over approximately 20 years.

Personalized Atrophy Risk Mapping in Age-Related Macular Degeneration

Purpose

To develop and validate an automatic retinal pigment epithelial and outer retinal atrophy (RORA) progression prediction model for nonexudative age-related macular degeneration (AMD) cases in optical coherence tomography (OCT) scans.

Methods

Longitudinal OCT data from 129 eyes/119 patients with RORA was collected and separated into training and testing groups. RORA was automatically segmented in all scans and additionally manually annotated in the test scans. OCT-based features such as layers thicknesses, mean reflectivity, and a drusen height map served as an input to the deep neural network. Based on the baseline OCT scan or the previous visit OCT, en face RORA predictions were calculated for future patient visits. The performance was quantified over time with the means of Dice scores and square root area errors.

Results

The average Dice score for segmentations at baseline was 0.85. When predicting progression from baseline OCTs, the Dice scores ranged from 0.73 to 0.80 for total RORA area and from 0.46 to 0.72 for RORA growth region. The square root area error ranged from 0.13 mm to 0.33 mm. By providing continuous time output, the model enabled creation of a patient-specific atrophy risk map.

Conclusions

We developed a machine learning method for RORA progression prediction, which provides continuous-time output. It was used to compute atrophy risk maps, which indicate time-to-RORA-conversion, a novel and clinically relevant way of representing disease progression.

Translational Relevance

Application of recent advances in artificial intelligence to predict patient-specific progression of atrophic AMD.