Structure-based design of nanobodies that inhibit seeding of Alzheimer's patient-extracted tau fibrils.

Despite much effort, antibody therapies for Alzheimer's disease (AD) have shown limited efficacy. Challenges to the rational design of effective antibodies include the difficulty of achieving specific affinity to critical targets, poor expression, and antibody aggregation caused by buried charges and unstructured loops. To overcome these challenges, we grafted previously determined sequences of fibril-capping amyloid inhibitors onto a camel heavy chain antibody scaffold. These sequences were designed to cap fibrils of tau, known to form the neurofibrillary tangles of AD, thereby preventing fibril elongation. The nanobodies grafted with capping inhibitors blocked tau aggregation in biosensor cells seeded with postmortem brain extracts from AD and progressive supranuclear palsy (PSP) patients. The tau capping nanobody inhibitors also blocked seeding by recombinant tau oligomers. Another challenge to the design of effective antibodies is their poor blood-brain barrier (BBB) penetration. In this study, we also designed a bispecific nanobody composed of a nanobody that targets a receptor on the BBB and a tau capping nanobody inhibitor, conjoined by a flexible linker. We provide evidence that the bispecific nanobody improved BBB penetration over the tau capping inhibitor alone after intravenous administration in mice. Our results suggest that the design of synthetic antibodies that target sequences that drive protein aggregation may be a promising approach to inhibit the prion-like seeding of tau and other proteins involved in AD and related proteinopathies.

Cryo-EM structures of the D290V mutant of the hnRNPA2 low-complexity domain suggests how D290V affects phase separation and aggregation.

Heterogeneous nuclear ribonucleoprotein A2 (hnRNPA2) is a human ribonucleoprotein that transports RNA to designated locations for translation via its ability to phase separate. Its mutated form, D290V, is implicated in multisystem proteinopathy known to afflict two families, mainly with myopathy and Paget's disease of bone. Here, we investigate this mutant form of hnRNPA2 by determining cryo-EM structures of the recombinant D290V low complexity domain. We find that the mutant form of hnRNPA2 differs from the WT fibrils in four ways. In contrast to the WT fibrils, the PY-nuclear localization signals in the fibril cores of all three mutant polymorphs are less accessible to chaperones. Also, the mutant fibrils are more stable than WT fibrils as judged by phase separation, thermal stability, and energetic calculations. Similar to other pathogenic amyloids, the mutant fibrils are polymorphic. Thus, these structures offer evidence to explain how a D-to-V missense mutation diverts the assembly of reversible, functional amyloid-like fibrils into the assembly of pathogenic amyloid, and may shed light on analogous conversions occurring in other ribonucleoproteins that lead to neurological diseases such as amyotrophic lateral sclerosis and frontotemporal dementia.

Intravitreal aflibercept 8 mg in diabetic macular oedema (PHOTON): 48-week results from a randomised, double-masked, non-inferiority, phase 2/3 trial.

BACKGROUND: A high-dose formulation of intravitreal aflibercept (8 mg) could improve treatment outcomes in diabetic macular oedema (DMO) by requiring fewer injections than the standard comparator, aflibercept 2 mg. We report efficacy and safety results of aflibercept 8 mg versus 2 mg in patients with DMO. METHODS: PHOTON was a randomised, double-masked, non-inferiority, phase 2/3 trial performed at 138 hospitals and specialty retina clinics in seven countries. Eligible patients were adults aged 18 years or older with type 1 or 2 diabetes and centre-involved DMO. Patients were randomly assigned (1:2:1) to intravitreal aflibercept 2 mg every 8 weeks (2q8), aflibercept 8 mg every 12 weeks (8q12), or aflibercept 8 mg every 16 weeks (8q16), following initial monthly dosing. From week 16, dosing intervals for the aflibercept 8 mg groups were shortened if patients met prespecified dose regimen modification criteria denoting disease activity. The primary endpoint was change from baseline in best-corrected visual acuity (BCVA) at week 48 (non-inferiority margin of 4 letters). Efficacy and safety analyses included all randomly assigned patients who received at least one dose of study treatment. This trial is registered with ClinicalTrials.gov (NCT04429503). FINDINGS: Between June 29, 2020, and June 28, 2021, 970 patients were screened for eligibility. After exclusions, 660 patients were enrolled and randomly assigned to receive aflibercept 8q12 (n=329), 8q16 (n=164), or 2q8 (n=167); two patients were randomly assigned in error and did not receive treatment. 658 (99·7%) patients were treated and included in the full analysis set and safety analysis set (8q12 n=328, 8q16 n=163, and 2q8 n=167). Mean patient age was 62·3 years (SD 10·4). 401 (61%) patients were male. 471 (72%) patients were White. Aflibercept 8q12 and 8q16 demonstrated non-inferior BCVA gains to aflibercept 2q8 (BCVA mean change from baseline 8·8 letters [SD 9·0] in the 8q12 group, 7·9 letters [8·4] in the 8q16 group, and 9·2 letters [9·0] in the 2q8 group). The difference in least squares means was -0·57 letters (95% CI -2·26 to 1·13, p value for non-inferiority <0·0001) between 8q12 and 2q8 and -1·44 letters (-3·27 to 0·39, p value for non-inferiority 0·0031) between aflibercept 8q16 and 2q8. Proportions of patients with ocular adverse events in the study eye were similar across groups (8q12 n=104 [32%], 8q16 n=48 [29%], and 2q8 n=46 [28%]). INTERPRETATION: Aflibercept 8 mg demonstrated efficacy and safety with extended dosing intervals and could decrease treatment burden in patients with DMO. FUNDING: Regeneron Pharmaceuticals and Bayer.

Cryo-EM structure of RNA-induced tau fibrils reveals a small C-terminal core that may nucleate fibril formation.

In neurodegenerative diseases including Alzheimer's and amyotrophic lateral sclerosis, proteins that bind RNA are found in aggregated forms in autopsied brains. Evidence suggests that RNA aids nucleation of these pathological aggregates; however, the mechanism has not been investigated at the level of atomic structure. Here, we present the 3.4-Å resolution structure of fibrils of full-length recombinant tau protein in the presence of RNA, determined by electron cryomicroscopy (cryo-EM). The structure reveals the familiar in-register cross-ß amyloid scaffold but with a small fibril core spanning residues Glu391 to Ala426, a region disordered in the fuzzy coat in all previously studied tau polymorphs. RNA is bound on the fibril surface to the positively charged residues Arg406 and His407 and runs parallel to the fibril axis. The fibrils dissolve when RNase is added, showing that RNA is necessary for fibril integrity. While this structure cannot exist simultaneously with the tau fibril structures extracted from patients' brains, it could conceivably account for the nucleating effects of RNA cofactors followed by remodeling as fibrils mature.

Pegcetacoplan for the treatment of geographic atrophy secondary to age-related macular degeneration (OAKS and DERBY): two multicentre, randomised, double-masked, sham-controlled, phase 3 trials.

BACKGROUND: Geographic atrophy is a leading cause of progressive, irreversible vision loss. The objectives of OAKS and DERBY were to assess the efficacy and safety of pegcetacoplan compared with sham treatment in patients with geographic atrophy. METHODS: OAKS and DERBY were two 24-month, multicentre, randomised, double-masked, sham-controlled, phase 3 studies, in which patients aged 60 years and older with geographic atrophy secondary to age-related macular degeneration were enrolled at 110 clinical sites and 122 clinical sites worldwide, respectively. Patients were randomly assigned (2:2:1:1) by central web-based randomisation system to intravitreal 15 mg per 0·1 mL pegcetacoplan monthly or every other month, or sham monthly or every other month using stratified permuted block randomisation (stratified by geographic atrophy lesion area at screening, history or presence of active choroidal neovascularisation in the eye not under assessment, and block size of six). Study site staff, patients, reading centre personnel, evaluating physicians, and the funder were masked to group assignment. Sham groups were pooled for the analyses. The primary endpoint was the change from baseline to month 12 in the total area of geographic atrophy lesions in the study eye based on fundus autofluorescence imaging, in the modified intention-to-treat population (ie, all patients who received one or more injections of pegcetacoplan or sham and had a baseline and at least one post-baseline value of lesion area). Key secondary endpoints (measured at 24 months) were change in monocular maximum reading speed of the study eye, change from baseline in mean functional reading independence index score, change from baseline in normal luminance best-corrected visual acuity score, and change from baseline in the mean threshold sensitivity of all points in the study eye by mesopic microperimetry (OAKS only). Safety analyses included patients who were randomly assigned and received at least one injection of pegcetacoplan or sham. The now completed studies are registered with ClinicalTrials.gov, NCT03525613 (OAKS) and NCT03525600 (DERBY). FINDINGS: Between Aug 30, 2018, and July 3, 2020, 1258 patients were enrolled in OAKS and DERBY. The modified intention-to-treat populations comprised 614 (96%) of 637 patients in OAKS (202 receiving pegcetacoplan monthly, 205 pegcetacoplan every other month, and 207 sham) and 597 (96%) of 621 patients in DERBY (201 receiving pegcetacoplan monthly, 201 pegcetacoplan every other month, and 195 sham). In OAKS, pegcetacoplan monthly and pegcetacoplan every other month significantly slowed geographic atrophy lesion growth by 21% (absolute difference in least-squares mean -0·41 mm2, 95% CI -0·64 to -0·18; p=0·0004) and 16% (-0·32 mm2, -0·54 to -0·09; p=0·0055), respectively, compared with sham at 12 months. In DERBY, pegcetacoplan monthly and pegcetacoplan every other month slowed geographic atrophy lesion growth, although it did not reach significance, by 12% (-0·23 mm2, -0·47 to 0·01; p=0·062) and 11% (-0·21 mm2, -0·44 to 0·03; p=0·085), respectively, compared with sham at 12 months. At 24 months, pegcetacoplan monthly and pegcetacoplan every other month slowed geographic atrophy lesion growth by 22% (-0·90 mm2, -1·30 to -0·50; p<0·0001) and 18% (-0·74 mm2, -1·13 to -0·36; p=0·0002) in OAKS, and by 19% (-0·75 mm2, -1·15 to -0·34; p=0·0004) and 16% (-0·63 mm2, -1·05 to -0·22; p=0·0030) in DERBY, respectively, compared with sham. There were no differences in key secondary visual function endpoints at 24 months. Serious ocular treatment-emergent adverse events were reported in five (2%) of 213, four (2%) of 212, and one (<1%) of 211 patients in OAKS, and in four (2%) of 206, two (1%) of 208, and two (1%) of 206 patients in DERBY receiving pegcetacoplan monthly, pegcetacoplan every other month, and sham, respectively, at 24 months. New-onset exudative age-related macular degeneration was reported in 24 (11%), 16 (8%), and four (2%) patients in OAKS, and in 27 (13%), 12 (6%), and nine (4%) patients in DERBY receiving pegcetacoplan monthly, pegcetacoplan every other month, and sham, respectively, at 24 months. INTERPRETATION: Pegcetacoplan, the first treatment approved by the US Food and Drug Administration for geographic atrophy, slowed geographic atrophy lesion growth with an acceptable safety profile. FUNDING: Apellis Pharmaceuticals.

LIGHTSITE III: 13-Month Efficacy and Safety Evaluation of Multiwavelength Photobiomodulation in Nonexudative (Dry) Age-Related Macular Degeneration Using the Lumithera Valeda Light Delivery System.

PURPOSE: The LIGHTSITE III study evaluated multiwavelength photobiomodulation (PBM) therapy in nonexudative (dry) age-related macular degeneration (AMD) using the LumiThera Valeda Light Delivery System. METHODS: LIGHTSITE III is a randomized, controlled trial to assess the safety and effectiveness of PBM in dry AMD. Subjects were given multiwavelength PBM (590, 660, and 850 nm) or Sham treatment delivered in a series of nine sessions over 3 to 5 weeks every four months over 24 months. Subjects were assessed for efficacy and safety outcomes. Data from the 13-month analysis are presented in this report. RESULTS: A total of 100 subjects (148 eyes) with dry AMD were randomized. LIGHTSITE III met the primary efficacy best-corrected visual acuity endpoint with a significant difference between PBM (n = 91 eyes) and Sham (n = 54 eyes) groups (Between group difference: 2.4 letters (SE 1.15), CI: -4.7 to -0.1, P = 0.02) (PBM alone: 5.4 letters (SE 0.96), CI: 3.5 to 7.3, P < 0.0001; Sham alone: 3.0 letters (SE 1.13), CI: 0.7-5.2, P < 0.0001). The PBM group showed a significant decrease in new onset geographic atrophy ( P = 0.024, Fisher exact test, odds ratio 9.4). A favorable safety profile was observed. CONCLUSION: LIGHTSITE III provides a prospective, randomized, controlled trial showing improved clinical and anatomical outcomes in intermediate dry AMD following PBM therapy.

SUPRACHOROIDAL SPACE INJECTION TECHNIQUE: Expert Panel Guidance.

PURPOSE: To develop professional guidelines for best practices for suprachoroidal space (SCS) injection, an innovative technique for retinal therapeutic delivery, based on current published evidence and clinical experience. METHODS: A panel of expert ophthalmologists reviewed current published evidence and clinical experience during a live working group meeting to define points of consensus and key clinical considerations to inform the development of guidelines for in-office SCS injection. RESULTS: Core consensus guidelines for in-office SCS injection were reached and reported by the expert panel. Current clinical evidence and physician experience supported SCS injection as a safe and effective method for delivering retinal and choroidal therapeutics. The panel established consensus on the rationale for SCS injection, including potential benefits relative to other intraocular delivery methods and current best practices in patient preparation, pre- and peri-injection management, SCS-specific injection techniques, and postinjection management and follow-up. CONCLUSION: These expert panel guidelines may support and promote standardization of SCS injection technique, with the goal of optimizing patient safety and outcomes. Some aspects of the procedure may reasonably be modified based on the clinical setting and physician judgment, as well as additional study.

Intrinsic electronic conductivity of individual atomically resolved amyloid crystals reveals micrometer-long hole hopping via tyrosines.

Proteins are commonly known to transfer electrons over distances limited to a few nanometers. However, many biological processes require electron transport over far longer distances. For example, soil and sediment bacteria transport electrons, over hundreds of micrometers to even centimeters, via putative filamentous proteins rich in aromatic residues. However, measurements of true protein conductivity have been hampered by artifacts due to large contact resistances between proteins and electrodes. Using individual amyloid protein crystals with atomic-resolution structures as a model system, we perform contact-free measurements of intrinsic electronic conductivity using a four-electrode approach. We find hole transport through micrometer-long stacked tyrosines at physiologically relevant potentials. Notably, the transport rate through tyrosines (105 s-1) is comparable to cytochromes. Our studies therefore show that amyloid proteins can efficiently transport charges, under ordinary thermal conditions, without any need for redox-active metal cofactors, large driving force, or photosensitizers to generate a high oxidation state for charge injection. By measuring conductivity as a function of molecular length, voltage, and temperature, while eliminating the dominant contribution of contact resistances, we show that a multistep hopping mechanism (composed of multiple tunneling steps), not single-step tunneling, explains the measured conductivity. Combined experimental and computational studies reveal that proton-coupled electron transfer confers conductivity; both the energetics of the proton acceptor, a neighboring glutamine, and its proximity to tyrosine influence the hole transport rate through a proton rocking mechanism. Surprisingly, conductivity increases 200-fold upon cooling due to higher availability of the proton acceptor by increased hydrogen bonding.

Micro-electron diffraction structure of the aggregation-driving N terminus of Drosophila neuronal protein Orb2A reveals amyloid-like ß-sheets.

Amyloid protein aggregation is commonly associated with progressive neurodegenerative diseases, however not all amyloid fibrils are pathogenic. The neuronal cytoplasmic polyadenylation element binding protein is a regulator of synaptic mRNA translation and has been shown to form functional amyloid aggregates that stabilize long-term memory. In adult Drosophila neurons, the cytoplasmic polyadenylation element binding homolog Orb2 is expressed as 2 isoforms, of which the Orb2B isoform is far more abundant, but the rarer Orb2A isoform is required to initiate Orb2 aggregation. The N terminus is a distinctive feature of the Orb2A isoform and is critical for its aggregation. Intriguingly, replacement of phenylalanine in the fifth position of Orb2A with tyrosine (F5Y) in Drosophila impairs stabilization of long-term memory. The structure of endogenous Orb2B fibers was recently determined by cryo-EM, but the structure adopted by fibrillar Orb2A is less certain. Here we use micro-electron diffraction to determine the structure of the first 9 N-terminal residues of Orb2A, at a resolution of 1.05 Å. We find that this segment (which we term M9I) forms an amyloid-like array of parallel in-register ß-sheets, which interact through side chain interdigitation of aromatic and hydrophobic residues. Our structure provides an explanation for the decreased aggregation observed for the F5Y mutant and offers a hypothesis for how the addition of a single atom (the tyrosyl oxygen) affects long-term memory. We also propose a structural model of Orb2A that integrates our structure of the M9I segment with the published Orb2B cryo-EM structure.

A Randomized Controlled Trial of OPT-302, a VEGF-C/D Inhibitor for Neovascular Age-Related Macular Degeneration.

PURPOSE: Neovascular (wet) age-related macular degeneration (nAMD) is driven by VEGFs A, C, and D, which promote angiogenesis and vascular permeability. Intravitreal injections of anti-VEGF-A drugs are the standard of care, but these do not inhibit VEGF-C and D, which may explain why many patients fail to respond fully. This trial aimed to test the safety and efficacy of OPT-302, a biologic inhibitor of VEGF-C and D, in combination with the anti-VEGF-A inhibitor ranibizumab. DESIGN: Dose-ranging, phase 2b, randomized, double-masked, sham-controlled trial. PARTICIPANTS: Participants with treatment-naive nAMD were enrolled from 109 sites across Europe, Israel, and the United States. METHODS: Participants were randomized to 6, 4-weekly, intravitreal injections of 0.5 mg OPT-302, 2.0 mg OPT-302, or sham, plus intravitreal 0.5 mg ranibizumab. MAIN OUTCOME MEASURES: The primary outcome was mean change in ETDRS best-corrected visual acuity (BCVA) at 24 weeks. Secondary outcomes (comparing baseline with week 24) were the proportion of participants gaining or losing ≥ 15 ETDRS BCVA letters; area under the ETDRS BCVA over time curve; change in spectral-domain OCT (SD-OCT) central subfield thickness; and change in intraretinal fluid and subretinal fluid on SD-OCT. RESULTS: Of 366 participants recruited from December 1, 2017, to November 30, 2018, 122, 123, and 121 were randomized to 0.5 mg OPT-302, 2.0 mg OPT-302, and sham, respectively. Mean (± standard deviation) visual acuity gain in the 2.0 mg OPT-302 group was significantly superior to sham (+14.2 ± 11.61 vs. +10.8 ± 11.52 letters; P = 0.01). The 0.5 mg OPT-302 group was not significantly different than the sham group (+9.44 ± 11.32 letters; P = 0.83). Compared with sham, the secondary BCVA outcomes favored the 2.0 mg OPT-302 group, with structural outcomes favoring both OPT-302 dosage groups. Adverse events (AEs) were similar across groups, with 16 (13.3%), 7 (5.6%), and 10 (8.3%) participants in the lower-dose, higher-dose, and sham groups, respectively, developing at least 1 serious AE. Two unrelated deaths both occurred in the sham arm. CONCLUSIONS: Significantly superior vision gain was observed with OPT-302 2.0 mg combination therapy, versus standard of care, with favorable safety (ClinicalTrials.gov identifier: NCT03345082). FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

PHASE 2 RANDOMIZED STUDY (ORION-1) OF A NOVEL, BIODEGRADABLE DEXAMETHASONE IMPLANT (AR-1105) FOR THE TREATMENT OF MACULAR EDEMA DUE TO CENTRAL OR BRANCH RETINAL VEIN OCCLUSION.

PURPOSE: AR-1105 is a novel biodegradable sustained-release dexamethasone implant designed to deliver 6-month durability. This Phase 2 study evaluated two AR-1105 formulations with different release profiles in patients with macular edema due to retinal vein occlusion. METHODS: Patients received a single intravitreal injection with 340 µg dexamethasone. In the initial phase, five patients received clinical formulation (CF) 1. In the randomized phase, 44 patients were randomized 1:1 to CF1 or CF2. The follow-up was 6 months. Patients had vision loss due to macular edema diagnosed ≥9 (central retinal vein occlusion) or ≥12 months (branch retinal vein occlusion) before screening, and could be treatment-naive or -experienced (if received prior steroids, must have demonstrated response). RESULTS: Both formulations improved vision and reduced retinal thickening from baseline across all visits. At Month 6, mean changes in best-corrected visual acuity were +4.3 and +8.0 letters, and mean changes in central subfield thickness were -93 µm and -211 µm in CF1 and CF2 randomized patients, respectively. Most common adverse events were reduced visual acuity, worsening macular edema, conjunctival hemorrhage, and increased intraocular pressure. No patients required surgery or laser for intraocular pressure control. CONCLUSION: Both formulations were well tolerated and demonstrated clinically meaningful and sustained improvements in vision and retinal thickening in patients with retinal vein occlusion with longstanding edema.

The α-synuclein hereditary mutation E46K unlocks a more stable, pathogenic fibril structure.

Aggregation of α-synuclein is a defining molecular feature of Parkinson's disease, Lewy body dementia, and multiple systems atrophy. Hereditary mutations in α-synuclein are linked to both Parkinson's disease and Lewy body dementia; in particular, patients bearing the E46K disease mutation manifest a clinical picture of parkinsonism and Lewy body dementia, and E46K creates more pathogenic fibrils in vitro. Understanding the effect of these hereditary mutations on α-synuclein fibril structure is fundamental to α-synuclein biology. We therefore determined the cryo-electron microscopy (cryo-EM) structure of α-synuclein fibrils containing the hereditary E46K mutation. The 2.5-Å structure reveals a symmetric double protofilament in which the molecules adopt a vastly rearranged, lower energy fold compared to wild-type fibrils. We propose that the E46K misfolding pathway avoids electrostatic repulsion between K46 and K80, a residue pair which form the E46-K80 salt bridge in the wild-type fibril structure. We hypothesize that, under our conditions, the wild-type fold does not reach this deeper energy well of the E46K fold because the E46-K80 salt bridge diverts α-synuclein into a kinetic trap-a shallower, more accessible energy minimum. The E46K mutation apparently unlocks a more stable and pathogenic fibril structure.

INTRAVITREAL NESVACUMAB (ANTIANGIOPOIETIN 2) PLUS AFLIBERCEPT IN DIABETIC MACULAR EDEMA: Phase 2 RUBY Randomized Trial.

PURPOSE: The purpose of this study was to compare intravitreal nesvacumab (anti-angiopoietin 2) plus aflibercept with intravitreal aflibercept injection (IAI) in diabetic macular edema. METHODS: The eyes (n = 302) were randomized (1:2:3) to nesvacumab 3 mg + aflibercept 2 mg (LD combo), nesvacumab 6 mg + aflibercept 2 mg (HD combo), or IAI 2 mg at baseline, Weeks 4 and 8. LD combo continued every 8 weeks (q8w). HD combo was rerandomized at Week 12 to q8w or every 12 weeks (q12w); IAI to q8w, q12w, or HD combo q8w through Week 32. RESULTS: Week 12 best-corrected visual acuity gains for LD and HD combo versus IAI were 6.8, 8.5, and 8.8 letters; Week 36 changes were similar. Central subfield retinal thickness reductions at Week 12 were -169.4, -184.0, and -174.6 µm (nominal P = 0.0183, HD combo vs. IAI); Week 36 reductions for LD combo and HD combo q8w and q12w versus IAI were -210.4, -223.4, and -193.7 versus -61.9 µm (nominal P < 0.05). At Week 12, 13.3% and 21.3% versus 15.2% had ≥2-step Diabetic Retinopathy Severity Scale improvement (LD and HD combos vs. IAI) and 59.6% and 66.3% versus 53.7% had complete foveal center fluid resolution. Safety was comparable across groups. CONCLUSION: Nesvacumab + aflibercept demonstrated no additional visual benefit over IAI. Anatomic improvements with HD combo may warrant further investigation.

PHASE 2 STUDY OF THE SAFETY AND EFFICACY OF BRIMONIDINE DRUG DELIVERY SYSTEM (BRIMO DDS) GENERATION 1 IN PATIENTS WITH GEOGRAPHIC ATROPHY SECONDARY TO AGE-RELATED MACULAR DEGENERATION.

PURPOSE: To evaluate the safety and efficacy of Brimonidine Drug Delivery System (Brimo DDS), a biodegradable intravitreal implant, in the treatment of geographic atrophy (GA) secondary to age-related macular degeneration. METHODS: Phase 2, randomized, multicenter, double-masked, 24-month study. Study eyes were treated (Day 1; Month 6 retreatment) with Brimo DDS 132 µg (n = 49), Brimo DDS 264 µg (n = 41), or sham procedure (n = 23). The primary timepoint for efficacy analysis was Month 12. RESULTS: Mean GA area growth at Month 12 was 1.78 mm2, 1.59 mm2, and 2.19 mm2 in the Brimo DDS 132 µg, 264 µg, and sham groups, respectively. Geographic atrophy area growth was consistently smaller with Brimo DDS 132 and 264 µg than sham; between-group differences were significant (P ≤ 0.032) at Month 3. In patients with baseline lesion area ≥6 mm2 (two-thirds of patients), GA lesion area and effective radius growth was reduced with Brimo DDS 132 and 264 µg at Month 12 (P ≤ 0.050 vs. sham). Treatment-related adverse events were usually injection procedure-related. CONCLUSION: Brimo DDS demonstrated a favorable safety profile and reduced GA lesion area growth at Month 3. Lesion growth at Month 12 was reduced in patients with baseline GA lesion area ≥6 mm2. The results support Phase 3 development.

The Use of Neuroprotective Agents in Treating Geographic Atrophy.

Geographic atrophy (GA) secondary to age-related macular degeneration accounts for close to one-quarter of cases of legal blindness in the USA and the UK. Despite this notable disease burden, the pathophysiology of GA is complex and not fully understood, and there is currently no approved treatment to prevent or slow its progression. GA is heterogeneous in its appearance and extent, and underlying associated traits such as drusen and complement factor polymorphisms vary between patients and by ethnicity, posing a challenge for treatment development. The root cause of vision loss in GA is photoreceptor death; therefore, protecting photoreceptors from damage and delaying their degeneration are key to successful GA treatment. There are multiple neuroprotective pathways that may contribute to protecting photoreceptors from damage, and compounds that target these pathways include antioxidants, neurotrophic factors, and catalases. However, the efficacy of previously trialled neuroprotective therapies in GA, such as brimonidine, tandospirone, and NT-501, has been inconsistent; this may be due to their target of action, method of delivery, and/or suboptimal duration of action. Neurotrophic factors, or molecules involved in neuroprotective signalling cascades, may be ideal agents for further investigation for the treatment of GA. Future neuroprotective strategies in GA must focus on the development of agents with a long duration of action that can combat the progression of chronic damage in GA to provide clinically meaningful benefits for patients.

Structure-based inhibitors halt prion-like seeding by Alzheimer's disease-and tauopathy-derived brain tissue samples.

In Alzheimer's disease (AD) and tauopathies, tau aggregation accompanies progressive neurodegeneration. Aggregated tau appears to spread between adjacent neurons and adjacent brain regions by prion-like seeding. Hence, inhibitors of this seeding offer a possible route to managing tauopathies. Here, we report the 1.0 Å resolution micro-electron diffraction structure of an aggregation-prone segment of tau with the sequence SVQIVY, present in the cores of patient-derived fibrils from AD and tauopathies. This structure illuminates how distinct interfaces of the parent segment, containing the sequence VQIVYK, foster the formation of distinct structures. Peptide-based fibril-capping inhibitors designed to target the two VQIVYK interfaces blocked proteopathic seeding by patient-derived fibrils. These VQIVYK inhibitors add to a panel of tau-capping inhibitors that targets specific polymorphs of recombinant and patient-derived tau fibrils. Inhibition of seeding initiated by brain tissue extracts differed among donors with different tauopathies, suggesting that particular fibril polymorphs of tau are associated with certain tauopathies. Donors with progressive supranuclear palsy exhibited more variation in inhibitor sensitivity, suggesting that fibrils from these donors were more polymorphic and potentially vary within individual donor brains. Our results suggest that a subset of inhibitors from our panel could be specific for particular disease-associated polymorphs, whereas inhibitors that blocked seeding by extracts from all of the tauopathies tested could be used to broadly inhibit seeding by multiple disease-specific tau polymorphs. Moreover, we show that tau-capping inhibitors can be transiently expressed in HEK293 tau biosensor cells, indicating that nucleic acid-based vectors can be used for inhibitor delivery.

Complement C3 Inhibitor Pegcetacoplan for Geographic Atrophy Secondary to Age-Related Macular Degeneration: A Randomized Phase 2 Trial.

PURPOSE: Geographic atrophy (GA), a late stage of age-related macular degeneration (AMD), is a major cause of blindness. Even while central visual acuity remains relatively well preserved, GA often causes considerable compromise of visual function and quality of life. No treatment currently exists. We evaluated the safety and efficacy of pegcetacoplan, a complement C3 inhibitor, for treatment of GA. DESIGN: Prospective, multicenter, randomized, sham-controlled phase 2 study. PARTICIPANTS: Two hundred forty-six patients with GA. METHODS: Patients with GA were assigned randomly in a 2:2:1:1 ratio to receive intravitreal injections of 15 mg pegcetacoplan monthly or every other month (EOM) or sham intravitreal injections monthly or EOM for 12 months with follow-up at months 15 and 18. Area and growth of GA were measured using fundus autofluorescence imaging. MAIN OUTCOME MEASURES: The primary efficacy end point was mean change in square root GA lesion area from baseline to month 12. Secondary outcome measures included mean change from baseline in GA lesion area without the square root transformation, distance of GA lesion from the fovea, best-corrected visual acuity (BCVA), low-luminance BCVA, and low-luminance visual acuity deficit. The primary safety end point was the number and severity of treatment-emergent adverse events. RESULTS: In patients receiving pegcetacoplan monthly or EOM, the GA growth rate was reduced by 29% (95% confidence interval [CI], 9-49; P = 0.008) and 20% (95% CI, 0-40; P = 0.067) compared with the sham treatment group. Post hoc analysis showed that the effect was greater in the second 6 months of treatment, with observed reductions of 45% (P = 0.0004) and 33% (P = 0.009) for pegcetacoplan monthly and EOM, respectively. Two cases of culture-positive endophthalmitis and 1 case of culture-negative endophthalmitis occurred in the pegcetacoplan monthly group. New-onset investigator-determined exudative AMD was reported more frequently in pegcetacoplan-treated eyes (18/86 eyes [20.9%] and 7/79 eyes [8.9%] in monthly and EOM groups, respectively) than in sham-treated eyes (1/81 eyes [1.2%]). CONCLUSIONS: Local C3 inhibition with pegcetacoplan resulted in statistically significant reductions in the growth of GA compared with sham treatment. Phase 3 studies will define the efficacy and safety profile further.

Consensus Nomenclature for Reporting Neovascular Age-Related Macular Degeneration Data: Consensus on Neovascular Age-Related Macular Degeneration Nomenclature Study Group.

PURPOSE: To establish a process to evaluate and standardize a state-of-the-art nomenclature for reporting neovascular age-related macular degeneration (AMD) data. DESIGN: Consensus meeting. PARTICIPANTS: An international panel of retina specialists, imaging and image reading center experts, and ocular pathologists. METHODS: During several meetings organized under the auspices of the Macula Society, an international study group discussed and codified a set nomenclature framework for classifying the subtypes of neovascular AMD and associated lesion components. MAIN OUTCOME MEASURES: A consensus classification of neovascular AMD. RESULTS: The study group created a standardized working definition of AMD. The components of neovascular AMD were defined and subclassified. Disease consequences of macular neovascularization were delineated. CONCLUSIONS: The framework of a consensus nomenclature system, a definition of AMD, and a delineation of the subtypes of neovascular AMD were developed. Establishing a uniform set of definitions will facilitate comparison of diverse patient groups and different studies. The framework presented is modified and updated readily, processes that are anticipated to occur on a periodic basis. The study group suggests that the consensus standards outlined in this article be used in future reported studies of neovascular AMD and clinical practice.

SUPPLEMENTAL SCLERAL BUCKLE IN THE ERA OF SMALL INCISION VITRECTOMY AND WIDE-ANGLE VIEWING SYSTEMS.

PURPOSE: To evaluate trends and outcomes of scleral buckle as adjunct to pars plana vitrectomy for management of retinal detachment. METHODS: Retrospective case series including 300 consecutive cases of retinal detachment that underwent pars plana vitrectomy. The series was divided into three consecutive groups: Group A (first 100 cases), Group B (second 100 cases), and Group C (third 100 cases). RESULTS: Three hundred eyes of 289 patients, mean age 61.0 years, were included in the study. The mean follow-up was 31.3 months for Group A, 28.5 months for Group B, and 12.0 months for Group C (P < 0.001). The baseline mean logarithm of the minimum angle of resolution equivalent was 1.58 for Group A, 1.31 for Group B, and 1.33 for Group C (P = 0.15). Supplemental scleral buckle was performed in 53% of Group A, 35% of Group B, and 17% of Group C (P < 0.001). Single surgery reattachment rate was 93% for Group A, 95% for Group B, and 97% for Group C (P = 0.48). The mean change in logarithm of the minimum angle of resolution equivalent was -0.84 for Group A, -0.81 for Group B, and -0.71 for Group C (P = 0.50). CONCLUSION: The study demonstrates decreasing use of supplemental scleral buckle in the era of small gauge vitrectomy surgery and wide-angle viewing systems while the outcomes remain stable. Selective, less frequent use of supplemental scleral buckle is compatible with good anatomical and visual outcomes.

The Developing Regorafenib Eye drops for neovascular Age-related Macular degeneration (DREAM) study: an open-label phase II trial.

AIMS: This programme investigated topical regorafenib, a multikinase inhibitor, in patients with neovascular age-related macular degeneration (nAMD). METHODS: Topical regorafenib was investigated in an open-label, phase IIa/b study in which patients with choroidal neovascularization (CNV) secondary to nAMD received regorafenib (25 µl, 30 mg ml-1 ) three times a day for 12 weeks. The primary endpoint of the phase II/a/b study was mean change in best-corrected visual acuity (BCVA) from baseline to weeks 4 and 12. RESULTS: In nAMD patients (N = 51), mean changes in BCVA were +1.2 [90% confidence interval (CI) -0.61, 2.97] and -2.4 (90% CI -4.18, -0.54) letters at weeks 4 and 12, respectively. Ocular treatment-emergent adverse events (TEAEs) (study eye) were reported in 21 patients by week 12. There was one serious ocular TEAE (visual acuity reduced) that was not drug related. Twenty patients required rescue (intravitreal ranibizumab). CONCLUSIONS: The programme was terminated after phase IIa ended because efficacy was lower than with current nAMD treatments. According to elaborate post hoc analyses, the most likely reason was insufficient exposure in the target compartment (back of the eye).