Functional and structural insights into activation of TRPV2 by weak acids.

Transient receptor potential (TRP) ion channels are involved in the surveillance or regulation of the acid-base balance. Here, we demonstrate that weak carbonic acids, including acetic acid, lactic acid, and CO2 activate and sensitize TRPV2 through a mechanism requiring permeation through the cell membrane. TRPV2 channels in cell-free inside-out patches maintain weak acid-sensitivity, but protons applied on either side of the membrane do not induce channel activation or sensitization. The involvement of proton modulation sites for weak acid-sensitivity was supported by the identification of titratable extracellular (Glu495, Glu561) and intracellular (His521) residues on a cryo-EM structure of rat TRPV2 (rTRPV2) treated with acetic acid. Molecular dynamics simulations as well as patch clamp experiments on mutant rTRPV2 constructs confirmed that these residues are critical for weak acid-sensitivity. We also demonstrate that the pore residue Glu609 dictates an inhibition of weak acid-induced currents by extracellular calcium. Finally, TRPV2-expression in HEK293 cells is associated with an increased weak acid-induced cytotoxicity. Together, our data provide new insights into weak acids as endogenous modulators of TRPV2.

Cryo-EM structure of SRP68/72 reveals an extended dimerization domain with RNA-binding activity.

The signal recognition particle (SRP) is a critical component in protein sorting pathways in all domains of life. Human SRP contains six proteins bound to the 7S RNA and their structures and functions have been mostly elucidated. The SRP68/72 dimer is the largest SRP component and is essential for SRP function. Although the structures of the SRP68/72 RNA binding and dimerization domains have been previously reported, the structure and function of large portions of the SRP68/72 dimer remain unknown. Here, we analyse full-length SRP68/72 using cryo-EM and report that SRP68/72 depend on each other for stability and form an extended dimerization domain. This newly observed dimerization domain is both a protein- and RNA-binding domain. Comparative analysis with current structural models suggests that this dimerization domain undergoes dramatic translocation upon SRP docking onto SRP receptor and eventually comes close to the Alu domain. We propose that the SRP68/72 dimerization domain functions by binding and detaching the Alu domain and SRP9/14 from the ribosomal surface, thus releasing elongation arrest upon docking onto the ER membrane.

Fluid Control in Neovascular Age-Related Macular Degeneration with Brolucizumab: An Analysis of the HAWK and HARRIER Phase 3 Trials.

INTRODUCTION: Neovascular age-related macular degeneration (nAMD) is characterized by exudation of fluid from abnormally growing blood vessels in the macula. Anti-vascular endothelial growth factor (VEGF) therapy is standard treatment for nAMD. Fluid resolution is used both as an indicator of disease control and to guide the frequency of treatment because of anti-VEGF therapy effectiveness in reducing neovascularization-related exudation. Herein reports a post hoc assessment of the HAWK and HARRIER trials comparing the efficacy and safety of brolucizumab with aflibercept in patients with nAMD. MATERIALS AND METHODS: HAWK randomized 1,078 patients with untreated, active choroidal neovascularization due to AMD in the study eye to receive brolucizumab 3, 6 mg or aflibercept 2 mg. In HARRIER, 739 patients received brolucizumab 6 mg or aflibercept 2 mg. Brolucizumab was injected at weeks 0, 4, and 8, and thereafter q12w unless disease activity was identified (injection interval: q8w). Aflibercept was injected q8w after the loading phase, aligned with approved dosing at study initiation. The objective of this analysis was to assess effects of brolucizumab versus aflibercept on retinal fluid resolution during two phase 3 trials (HAWK and HARRIER) in patients with nAMD. Anatomical assessments for intraretinal fluid (IRF) and subretinal fluid (SRF) were performed every 4 weeks by spectral domain optical coherence tomography. Sustained dryness was defined as a patient being fluid-free (SRF and IRF) on ≥3 consecutive visits. Time to sustained dryness was determined by Kaplan-Meier estimates. RESULTS: At week 96, fluid resolution (absence of IRF and SRF) was achieved by more brolucizumab- (6 mg; 76.1%) versus aflibercept-treated patients (63.1%; p = 0.0002, HAWK); 75.4% versus 61.8% (p < 0.0001, HARRIER). More patients achieved sustained dryness with brolucizumab versus aflibercept: at 96 weeks, 87.9% (brolucizumab 3 mg) and 86.1% (brolucizumab 6 mg) versus 82.0% (aflibercept) in HAWK, and 91.2% (brolucizumab) versus 78.0% (aflibercept) in HARRIER. Sustained dryness was achieved faster and hence with fewer brolucizumab injections. DISCUSSION/CONCLUSION: Brolucizumab dried the macula in patients with nAMD faster and to a greater degree than aflibercept. Achieving sustained dryness faster, and therefore with fewer injections, provides an opportunity for earlier decisions relating to treatment interval extension potentially reducing treatment burden.

Efficacy and Safety of Intravitreal Aflibercept Treat and Extend for Polypoidal Choroidal Vasculopathy in the ATLANTIC Study: A Randomized Clinical Trial.

IMPORTANCE: Polypoidal choroidal vasculopathy (PCV) is far less common and studied in a Caucasian population than in an Asian population, and the optimal treatment approach remains to be confirmed. METHODS: A 52-week, double-masked, sham-controlled, phase 4, investigator-initiated randomized clinical trial (RCT) in naive symptomatic Caucasian patients with PCV treated with aflibercept in a treat-and-extend regimen (T&E) (intravitreal aflibercept injection [IVAI] T&E). Patients were randomized at week 16 to receive IVAI T&E plus either sham photodynamic therapy (PDT) or standard fluence PDT with verteporfin. The main outcome measures were changes in best-corrected visual acuity (BCVA) from baseline to 52 weeks and polyp occlusion at week 52. Data are presented as median (interquartile range [IQR]) for BCVA, number of IVAI, and change in central retinal thickness (CRT). RESULTS: Of the 50 patients included in the study, 48 patients completed the 52 weeks of follow-up. During this period, a significant median (IQR) BCVA gain of 6 [2-12] Early Treatment Diabetic Retinopathy Study letters was observed for all patients (p < 0.001), after 8 (7-9) injections, with a significant reduction of -93.0 [-154.0, -44.0] µm in central macular thickness (p < 0.001). Using indocyanine green angiography, a complete occlusion of polypoidal lesions was documented in 72% of the cases. Still, no significant difference was detected between the sham PDT and the aflibercept PDT arms, at week 52, for BCVA change (6.5 [2-11] vs. 5 [2-13] letters (p = 0.98)), number of IVAIs (8.5 [7-9] vs. 8 [7-9] (p = 0.21)), change in CRT (-143 [-184; -47] vs. -89 [-123; -41.5] µm [p = 0.23]), and rates of complete polyp occlusion: 77 versus 68% (p = 0.53) or presence of fluid: 68 versus 57% (p = 0.56). No serious ocular adverse events were registered in the 2 arms. CONCLUSIONS AND RELEVANCE: To our knowledge, this is the first RCT to compare aflibercept T&E monotherapy with aflibercept T&E plus verteporfin PDT in a Caucasian population with PCV. Aflibercept monotherapy in a T&E showed to be effective and safe with a significant median BCVA improvement of 6 letters and a complete occlusion of polypoidal lesions in near 3 quarters of the eyes, at 1 year. As only 22% of the eyes underwent PDT treatment, the benefit of combined treatment for PCV in Caucasian patients could not be definitively elucidated from this study. TRIAL REGISTRATION: The clinical trial was registered in ClinicalTrials.gov Identifier NCT02495181 and the European Union Drug Regulating Authorities Clinical Trials Database EudraCT No. 2015-001368-20.

HAWK and HARRIER: Ninety-Six-Week Outcomes from the Phase 3 Trials of Brolucizumab for Neovascular Age-Related Macular Degeneration.

PURPOSE: To report the 96-week outcomes from HAWK and HARRIER. DESIGN: Phase 3, prospective, randomized, double-masked, multicenter studies comparing efficacy and safety of brolucizumab 3 mg (HAWK only) and 6 mg with aflibercept 2 mg in eyes with neovascular age-related macular degeneration (nAMD). PARTICIPANTS: Treatment-naïve eyes with nAMD were randomized 1:1:1 to brolucizumab 3 mg (n = 358), brolucizumab 6 mg (n = 360), aflibercept 2 mg (n = 360; HAWK) or 1:1 to brolucizumab 6 mg (n = 370), aflibercept 2 mg (n = 369; HARRIER). METHODS: After 3 monthly loading doses, brolucizumab patients received every (q)-12-week (w) dosing, possibly adjusting to q8w dosing if disease activity was present at predefined disease activity assessment (DAA) visits. Aflibercept was dosed in a fixed q8w regimen. Visual and anatomic parameters were assessed throughout. Primary end point was at week 48 (48w), confirmed at 96w. MAIN OUTCOME MEASURES: Mean best-corrected visual acuity (BCVA) change from baseline, proportion of patients on an q12w regimen, retinal thickness, retinal fluid changes, and safety, all to 96w. RESULTS: Mean change (least squares [LS] mean ± standard error) in BCVA from baseline to 96w in HAWK was 5.6±0.79 Early Treatment Diabetic Retinopathy Study (ETDRS) letters for brolucizumab 3 mg, 5.90±0.78 letters for brolucizumab 6 mg, and 5.3±0.78 letters for aflibercept and in HARRIER was 6.1±0.73 letters for brolucizumab 6 mg and 6.6 ± 0.73 letters for aflibercept. Greater central subfield thickness reductions were observed with brolucizumab 6 mg versus aflibercept in HAWK (LS mean, -174.8 µm vs. -148.7 µm; 95% confidence interval for treatment difference, -46.2 to -5.9 µm; P = 0.0115) and HARRIER (LS mean, -197.7 µm vs. -155.1 µm; 95% confidence interval for treatment difference, -62.0 to -23.3 µm; P < 0.0001). The proportions of eyes with intraretinal fluid and/or subretinal fluid (IRF/SRF) at 96w in HAWK were 31% (P = 0.0688) and 24% (P = 0.0002) for brolucizumab 3 mg and 6 mg and 37% for aflibercept, whereas in HARRIER, they were 24% for brolucizumab 6 mg (P < 0.0001) and 39% for aflibercept. At 92w (last DAA), a 45.4% and 38.6% probability was observed for brolucizumab 6 mg patients of maintaining an q12w treatment regimen in HAWK and HARRIER, respectively. Brolucizumab exhibited an overall well-tolerated safety profile. CONCLUSIONS: Visual outcomes from 48w to 96w confirm the efficacy achieved at 48w. Brolucizumab demonstrated greater fluid resolution compared with aflibercept. The q12w potential for brolucizumab observed at 48w was maintained to 96w.

Polypoidal Choroidal Vasculopathy: Consensus Nomenclature and Non-Indocyanine Green Angiograph Diagnostic Criteria from the Asia-Pacific Ocular Imaging Society PCV Workgroup.

PURPOSE: To develop consensus terminology in the setting of polypoidal choroidal vasculopathy (PCV) and to develop and validate a set of diagnostic criteria not requiring indocyanine green angiography (ICGA) for differentiating PCV from typical neovascular age-related macular degeneration (nAMD) based on a combination of OCT and color fundus photography findings. DESIGN: Evaluation of diagnostic test results. PARTICIPANTS: Panel of retina specialists. METHODS: As part of the Asia-Pacific Ocular Imaging Society, an international group of experts surveyed and discussed the published literature regarding the current nomenclature and lesion components for PCV, and proposed an updated consensus nomenclature that reflects our latest understanding based on imaging and histologic reports. The workgroup evaluated a set of diagnostic features based on OCT images and color fundus photographs for PCV that may distinguish it from typical nAMD and assessed the performance of individual and combinations of these non-ICGA features, aiming to propose a new set of diagnostic criteria that does not require the use of ICGA. The final recommendation was validated in 80 eyes from 2 additional cohorts. MAIN OUTCOME MEASURES: Consensus nomenclature system for PCV lesion components and non-ICGA-based criteria to differentiate PCV from typical nAMD. RESULTS: The workgroup recommended the terms polypoidal lesion and branching neovascular network for the 2 key lesion components in PCV. For the diagnosis of PCV, the combination of 3 OCT-based major criteria (sub-retinal pigment epithelium [RPE] ring-like lesion, en face OCT complex RPE elevation, and sharp-peaked PED) achieved an area under the receiver operating characteristic curve of 0.90. Validation of this new scheme in a separate subset 80 eyes achieved an accuracy of 82%. CONCLUSIONS: We propose updated terminology for PCV lesion components that better reflects the nature of these lesions and is based on international consensus. A set of practical diagnostic criteria applied easily to spectral-domain OCT results can be used for diagnosing PCV with high accuracy in clinical settings in which ICGA is not performed routinely.

Anti-VEGF intravitreal injections in the era of COVID-19: responding to different levels of epidemic pressure.

PURPOSE: Following the first wave of the COVID-19 pandemic in early 2020, the easing of strict measures to reduce its spread has led to a resurgence of cases in many countries at both the national and local level. This article addresses how guidance for ophthalmologists on managing patients with retinal disease receiving intravitreal injections of anti-vascular endothelial growth factor (VEGF) during the pandemic should be adapted to the local epidemic pressure, with more or less stringent measures implemented according to the ebb and flow of the pandemic. METHODS: The Vision Academy's membership of international retinal disease experts analyzed guidance for anti-VEGF intravitreal injections during the COVID-19 pandemic and graded the recommendations according to three levels of increasing epidemic pressure. The revised recommendations were discussed, refined, and voted on by the 14-member Vision Academy Steering Committee for consensus. RESULTS: Protocols to minimize the exposure of patients and healthcare staff to COVID-19, including use of personal protective equipment, physical distancing, and hygiene measures, should be routinely implemented and intensified according to local infection rates and pressure on the hospital/clinic or healthcare system. In areas with many COVID-19-positive clusters, additional measures including pre-screening of patients, postponement of non-urgent appointments, and simplification of complex intravitreal anti-VEGF regimens should be considered. Treatment prioritization for those at greatest risk of irreversible vision loss should be implemented in areas where COVID-19 cases are increasing exponentially and healthcare resources are strained. CONCLUSION: Consistency in monitoring of local infection rates and adjustment of clinical practice accordingly will be required as we move forward through the COVID-19 era. Ophthalmologists must continue to carefully weigh the risk-benefits to minimize the exposure of patients and healthcare staff to COVID-19, ensure that patients receive sight-saving treatment, and avoid the potential long-term impact of prolonged treatment postponement.

MANAGEMENT OF RETINAL PIGMENT EPITHELIUM TEAR DURING ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR THERAPY.

PURPOSE: This article aims to review current evidence on the development, diagnosis, and management of retinal pigment epithelium (RPE) tear during anti-vascular endothelial growth factor (VEGF) therapy. METHODS: Literature searches were performed using MEDLINE/PubMed databases (cut-off date: August 2019). RESULTS: Three key recommendations were made based on existing literature and clinical experience: 1) Multimodal imaging with color fundus photography, optical coherence tomography, near-infrared reflectance imaging, fundus autofluorescence imaging, optical coherence tomography-angiography, and/or fluorescein angiography are recommended to diagnose RPE tear and assess risk factors. Retinal pigment epithelium tears can be graded by size and foveal involvement. 2) Patients at high risk of developing RPE tear should be monitored after each anti-VEGF injection. If risk factors worsen, it is not yet definitively known whether anti-VEGF administration should be more frequent, or alternatively stopped in such patients. Prospective research into high-risk characteristics is needed. 3) After RPE tear develops, anti-VEGF treatment should be continued in patients with active disease (as indicated by presence of intraretinal or subretinal fluid), although cessation of therapy should be considered in eyes with multilobular tears. CONCLUSION: Although evidence to support the assumption that anti-VEGF treatment contributes to development of RPE tear is not definitive, some data suggest this link.

HAWK and HARRIER: Phase 3, Multicenter, Randomized, Double-Masked Trials of Brolucizumab for Neovascular Age-Related Macular Degeneration.

PURPOSE: Two similarly designed phase 3 trials (HAWK and HARRIER) compared brolucizumab, a single-chain antibody fragment that inhibits vascular endothelial growth factor-A, with aflibercept to treat neovascular age-related macular degeneration (nAMD). DESIGN: Double-masked, multicenter, active-controlled, randomized trials. PARTICIPANTS: Patients (N = 1817) with untreated, active choroidal neovascularization due to age-related macular degeneration in the study eye. INTERVENTION: Patients were randomized to intravitreal brolucizumab 3 mg (HAWK only) or 6 mg or aflibercept 2 mg. After loading with 3 monthly injections, brolucizumab-treated eyes received an injection every 12 weeks (q12w) and were interval adjusted to every 8 weeks (q8w) if disease activity was present; aflibercept-treated eyes received q8w dosing. MAIN OUTCOME MEASURES: The primary hypothesis was noninferiority in mean best-corrected visual acuity (BCVA) change from baseline to Week 48 (margin: 4 letters). Other key end points included the percentage of patients who maintained q12w dosing through Week 48 and anatomic outcomes. RESULTS: At Week 48, each brolucizumab arm demonstrated noninferiority to aflibercept in BCVA change from baseline (least squares [LS] mean, +6.6 [6 mg] and +6.1 [3 mg] letters with brolucizumab vs. +6.8 letters with aflibercept [HAWK]; +6.9 [brolucizumab 6 mg] vs. +7.6 [aflibercept] letters [HARRIER]; P < 0.001 for each comparison). Greater than 50% of brolucizumab 6 mg-treated eyes were maintained on q12w dosing through Week 48 (56% [HAWK] and 51% [HARRIER]). At Week 16, after identical treatment exposure, fewer brolucizumab 6 mg-treated eyes had disease activity versus aflibercept in HAWK (24.0% vs. 34.5%; P = 0.001) and HARRIER (22.7% vs. 32.2%; P = 0.002). Greater central subfield thickness reductions from baseline to Week 48 were observed with brolucizumab 6 mg versus aflibercept in HAWK (LS mean -172.8 µm vs. -143.7 µm; P = 0.001) and HARRIER (LS mean -193.8 µm vs. -143.9 µm; P < 0.001). Anatomic retinal fluid outcomes favored brolucizumab over aflibercept. Overall, adverse event rates were generally similar with brolucizumab and aflibercept. CONCLUSIONS: Brolucizumab was noninferior to aflibercept in visual function at Week 48, and >50% of brolucizumab 6 mg-treated eyes were maintained on q12w dosing interval through Week 48. Anatomic outcomes favored brolucizumab over aflibercept. Overall safety with brolucizumab was similar to aflibercept (ClinicalTrials.gov; NCT02307682, NCT02434328).

Brolucizumab: Evolution through Preclinical and Clinical Studies and the Implications for the Management of Neovascular Age-Related Macular Degeneration.

Improving or maintaining visual acuity is the main goal for the treatment of neovascular age-related macular degeneration (nAMD). Current nAMD standard of care dictates frequent intravitreal (IVT) anti-vascular endothelial growth factor (VEGF) injections, which places a substantial burden on patients, caregivers, and physicians. Brolucizumab, a newly developed anti-VEGF molecule for nAMD treatment, has demonstrated longer durability and improvement in visual and anatomic outcomes in clinical studies in a q12-week regimen, indicating its potential to reduce treatment burden as an important therapeutic tool in nAMD management. This review focuses on the development of brolucizumab and the preclinical and clinical studies evaluating its efficacy, tolerability, and safety. Brolucizumab (also known as "RTH258" and "ESBA1008") is a humanized, single-chain variable fragment (scFv) antibody with a molecular mass of approximately 26 kDa that inhibits VEGF-A. Preclinical studies show that brolucizumab readily penetrates the retina to reach the retinal pigment epithelium (RPE)/choroid with minimal subsequent systemic exposure. The safety, tolerability, and efficacy of a single IVT brolucizumab administration in patients with treatment-naïve nAMD were first demonstrated in the SEE Phase 1/2 study. The OSPREY Phase 2 study showed brolucizumab to be as efficacious as aflibercept in a q8-week regimen with regard to best-corrected visual acuity (BCVA) and brolucizumab achieving greater fluid resolution. Brolucizumab-treated patients in the OSPREY study were subsequently challenged with a q12-week dosing interval, and the outcomes provided key information for the study design and end points of the Phase 3 studies. In the HAWK and HARRIER Phase 3 studies, after 3 monthly loading injections, brolucizumab treatment regimen (q12-week or q8-week) was guided by individual disease activity assessment using functional and anatomic parameters (central subfield thickness [CST], intraretinal fluid [IRF], or subretinal fluid [SRF]) versus aflibercept (q8-week). Fewer brolucizumab 6-mg treated eyes had disease activity versus aflibercept, and anatomic outcome results at weeks 16 and 48 demonstrate brolucizumab as a potent drying agent. Moreover, of patients treated with 6 mg brolucizumab, 55.6% and 51.0% maintained a q12-week dosing interval immediately after the loading phase until week 48 in HAWK and HARRIER, respectively. These Phase 3 studies demonstrated that the brolucizumab q12-week regimen maintains efficacy and safety while reducing treatment burden associated with regular IVT injections for patients with nAMD.

Guidance for anti-VEGF intravitreal injections during the COVID-19 pandemic.

PURPOSE: There is an urgent need to address how to best provide ophthalmic care for patients with retinal disease receiving intravitreal injections with anti-vascular endothelial growth factor agents during the ongoing global COVID-19 pandemic. This article provides guidance for ophthalmologists on how to deliver the best possible care for patients while minimizing the risk of infection. METHODS: The Vision Academy's Steering Committee of international retinal disease experts convened to discuss key considerations for managing patients with retinal disease during the COVID-19 pandemic. After reviewing the existing literature on the issue, members put forward recommendations that were systematically refined and voted on to develop this guidance. RESULTS: The considerations focus on the implementation of steps to minimize the exposure of patients and healthcare staff to COVID-19. These include the use of personal protective equipment, adherence to scrupulous hygiene and disinfection protocols, pre-screening to identify symptomatic patients, and reducing the number of people in waiting rooms. Other important measures include triaging of patients to identify those at the greatest risk of irreversible vision loss and prioritization of treatment visits over monitoring visits where possible. In order to limit patient exposure, ophthalmologists should refrain from using treatment regimens that require frequent monitoring. CONCLUSION: Management of patients with retinal disease receiving intravitreal injections during the COVID-19 pandemic will require adjustment to regular clinical practice to minimize the risk of exposure of patients and healthcare staff, and to prioritize those with the greatest medical need. The safety of patients and healthcare staff should be of paramount importance in all decision-making.

REAL-WORLD EFFECTIVENESS AND SAFETY OF RANIBIZUMAB TREATMENT IN PATIENTS WITH AND WITHOUT POLYPOIDAL CHOROIDAL VASCULOPATHY: Twelve-Month Results From the LUMINOUS Study.

PURPOSE: To evaluate the real-world effectiveness and safety of intravitreal ranibizumab 0.5 mg in treatment-naive patients with and without polypoidal choroidal vasculopathy (PCV). METHODS: Assessment of neovascular age-related macular degeneration patients with or without PCV after 12 months of ranibizumab treatment during the LUMINOUS study. Outcome measures were visual acuity and central retinal thickness changes from baseline and the rate of ocular adverse events. RESULTS: At baseline, 572 and 5,644 patients were diagnosed with and without PCV, respectively. The mean visual acuity gain from baseline at Month 12 in the PCV and non-PCV groups was +5.0 and +3.0 letters, respectively; these gains were achieved with a mean of 4.4 and 5.1 ranibizumab injections. Eighty percent of PCV patients and 72.2% of non-PCV patients who had baseline visual acuity ≥73 letters maintained this level of vision at Month 12; 20.6% and 17.9% of patients with baseline visual acuity <73 letters achieved visual acuity ≥73 letters in these groups. Greater reductions in central retinal thickness from baseline were also observed for the PCV group versus the non-PCV group. The rate of serious ocular adverse events was 0.7% (PCV group) and 0.9% (non-PCV group). CONCLUSION: LUMINOUS confirms the effectiveness and safety of ranibizumab in treatment-naive patients with PCV.

Polypoidal Choroidal Vasculopathy: Definition, Pathogenesis, Diagnosis, and Management.

Polypoidal choroidal vasculopathy (PCV) is an age-related macular degeneration (AMD) subtype and is seen particularly in Asians. Previous studies have suggested disparity in response to intravitreal injections of anti-vascular endothelial growth factor (VEGF) agents between PCV and typical AMD, and thus, the preferred treatment for PCV has remained unclear. Recent research has provided novel insights into the pathogenesis of PCV, and imaging studies based on OCT suggest that PCV belongs to a spectrum of conditions characterized by pachychoroid, in which disturbance in the choroidal circulation seems to be central to its pathogenesis. Advances in imaging, including enhanced depth imaging, swept-source OCT, en face OCT, and OCT angiography, have facilitated the diagnosis of PCV. Importantly, 2 large, multicenter randomized clinical trials evaluating the safety and efficacy of anti-VEGF monotherapy and combination with photodynamic therapy (PDT) recently reported initial first-year outcomes, providing level I evidence to guide clinicians in choosing the most appropriate therapy for PCV. In this review, we summarize the latest updates in the epidemiologic features, pathogenesis, and advances in imaging and treatment trials, with a focus on the most recent key clinical trials. Finally, we propose current management guidelines and recommendations to help clinicians manage patients with PCV. Remaining gaps in current understanding of PCV, such as significance of polyp closure, high recurrence rate, and heterogeneity within PCV, are highlighted where further research is needed.

Long-term outcomes of myopic choroidal neovascularisation treated with combined ranibizumab and dexamethasone characterised by multi-modal imaging.

AIM: To characterise the long-term outcomes of myopic choroidal neovascularisation (mCNV) treated with combined ranibizumab and dexamethasone, with the use of multi-modal imaging. METHODS: A retrospective study of 20 eyes with mCNV treated with intra-vitreal ranibizumab and dexamethasone on a treat-as-needed basis were followed up for a mean period of 47 months (range 19-81 months). RESULTS: The mean age was 55 ± 16 years, with mean refractive error of -9.0 diopters. Subfoveal mCNV was seen in 11 eyes (52 %) and the others were juxtafoveal. At the final visit, 13 patients (65 %) had improvement, while four patients (20 %) had worsening in vision. The average number of ranibizumab and dexamethasone injections required was 3 ± 1.7. There was a significant improvement in the mean visual acuity, reduction of the central retinal thickness, and an enlargement of the area of chorioretinal atrophy. The mean rate of increase in chorioretinal atrophy area was 0.05 ± 0.09 mm2/month. Disruption of the photoreceptor layer, fragmentation of the retinal pigment epithelium, and breaks in the Bruch's membrane with a hyper-reflective lesion causing separation of the outer retinal layers were changes associated with active mCNV seen on optical coherence tomography (OCT). CONCLUSION: Visual outcomes of mCNV treated with ranibizumab and dexamethasone on a treat-as-needed basis have favourable visual acuity outcomes. Using multi-modal imaging to monitor treatment response, chorioretinal atrophy, which may be related to visual function, should be used as an additional outcome measure to study the effect of combination treatment versus monotherapy.

The REVEAL Study: Ranibizumab Monotherapy or Combined with Laser versus Laser Monotherapy in Asian Patients with Diabetic Macular Edema.

OBJECTIVE: The primary study hypothesis was that ranibizumab 0.5 mg monotherapy or combined with laser is superior to laser monotherapy based on mean average change in best-corrected visual acuity (BCVA) over 12 months in Asian patients with visual impairment resulting from diabetic macular edema (DME). DESIGN: A 12-month, randomized, double-masked, multicenter, laser-controlled, phase III study. PARTICIPANTS: Three hundred ninety-six patients aged ≥18 years, with type 1 or 2 diabetes mellitus, BCVA of 78-39 Early Treatment Diabetic Retinopathy Study (ETDRS) letters, and visual impairment resulting from DME. METHODS: Patients were randomized to ranibizumab + sham laser (n = 133), ranibizumab + active laser (n = 132), or sham injection + active laser (n = 131). Ranibizumab/sham injections were administered on day 1 and continued monthly. As of month 3, monthly injections were continued if stable vision was not reached. Treatment was reinitiated if BCVA decreased because of DME progression. Active/sham laser was administered on day 1 and thereafter according to ETDRS guidelines. MAIN OUTCOME MEASURES: Average change in BCVA from baseline to months 1 through 12, central retinal subfield thickness (CRST), and safety over 12 months. RESULTS: Ranibizumab monotherapy or combined with laser was superior to laser in improving mean average change in BCVA from baseline to months 1 through 12 (+5.9 and +5.7 vs +1.4 letters). At month 12, greater proportion of patients gained ≥15 letters with ranibizumab and ranibizumab + laser compared with laser (18.8% and 17.8% vs 7.8%). Mean CRST reduced significantly from baseline to month 12 with ranibizumab (-134.6 µm) and ranibizumab + laser (-171.8 µm) versus laser (-57.2 µm). Patients received a mean of 7.8 and 7.0 ranibizumab injections in the ranibizumab and ranibizumab + laser arms, respectively, and 1.5-1.9 active laser across treatment arms over 12 months. Conjunctival hemorrhage was the most common ocular, whereas nasopharyngitis and hypertension were the most common nonocular adverse events. Ranibizumab was not associated with any cases of cerebrovascular hemorrhage and cerebrovascular ischemia. No death related to study treatment was reported. CONCLUSIONS: Ranibizumab monotherapy or combined with laser showed superior BCVA improvements over laser treatment alone in Asian patients with visual impairment resulting from DME. No new ocular or nonocular safety findings were observed and treatment was well tolerated over 12 months.

Structural and quantum chemical basis for OCP-mediated quenching of phycobilisomes.

Cyanobacteria use large antenna complexes called phycobilisomes (PBSs) for light harvesting. However, intense light triggers non-photochemical quenching, where the orange carotenoid protein (OCP) binds to PBS, dissipating excess energy as heat. The mechanism of efficiently transferring energy from phycocyanobilins in PBS to canthaxanthin in OCP remains insufficiently understood. Using cryo-electron microscopy, we unveiled the OCP-PBS complex structure at 1.6- to 2.1-angstrom resolution, showcasing its inherent flexibility. Using multiscale quantum chemistry, we disclosed the quenching mechanism. Identifying key protein residues, we clarified how canthaxanthin's transition dipole moment in its lowest-energy dark state becomes large enough for efficient energy transfer from phycocyanobilins. Our energy transfer model offers a detailed understanding of the atomic determinants of light harvesting regulation and antenna architecture in cyanobacteria.