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Featured researches published by Victor Chong.


Ophthalmology | 2012

Intravitreal aflibercept (VEGF trap-eye) in wet age-related macular degeneration.

Jeffrey S. Heier; David M. Brown; Victor Chong; Jean François Korobelnik; Peter K. Kaiser; Quan Dong Nguyen; Bernd Kirchhof; Allen C. Ho; Yuichiro Ogura; George D. Yancopoulos; Neil Stahl; Robert Vitti; Alyson J. Berliner; Yuhwen Soo; Majid Anderesi; Georg Groetzbach; Bernd Sommerauer; Rupert Sandbrink; Christian Simader; Ursula Schmidt-Erfurth

OBJECTIVE Two similarly designed, phase-3 studies (VEGF Trap-Eye: Investigation of Efficacy and Safety in Wet AMD [VIEW 1, VIEW 2]) of neovascular age-related macular degeneration (AMD) compared monthly and every-2-month dosing of intravitreal aflibercept injection (VEGF Trap-Eye; Regeneron, Tarrytown, NY, and Bayer HealthCare, Berlin, Germany) with monthly ranibizumab. DESIGN Double-masked, multicenter, parallel-group, active-controlled, randomized trials. PARTICIPANTS Patients (n = 2419) with active, subfoveal, choroidal neovascularization (CNV) lesions (or juxtafoveal lesions with leakage affecting the fovea) secondary to AMD. INTERVENTION Patients were randomized to intravitreal aflibercept 0.5 mg monthly (0.5q4), 2 mg monthly (2q4), 2 mg every 2 months after 3 initial monthly doses (2q8), or ranibizumab 0.5 mg monthly (Rq4). MAIN OUTCOME MEASURES The primary end point was noninferiority (margin of 10%) of the aflibercept regimens to ranibizumab in the proportion of patients maintaining vision at week 52 (losing <15 letters on Early Treatment Diabetic Retinopathy Study [ETDRS] chart). Other key end points included change in best-corrected visual acuity (BCVA) and anatomic measures. RESULTS All aflibercept groups were noninferior and clinically equivalent to monthly ranibizumab for the primary end point (the 2q4, 0.5q4, and 2q8 regimens were 95.1%, 95.9%, and 95.1%, respectively, for VIEW 1, and 95.6%, 96.3%, and 95.6%, respectively, for VIEW 2, whereas monthly ranibizumab was 94.4% in both studies). In a prespecified integrated analysis of the 2 studies, all aflibercept regimens were within 0.5 letters of the reference ranibizumab for mean change in BCVA; all aflibercept regimens also produced similar improvements in anatomic measures. Ocular and systemic adverse events were similar across treatment groups. CONCLUSIONS Intravitreal aflibercept dosed monthly or every 2 months after 3 initial monthly doses produced similar efficacy and safety outcomes as monthly ranibizumab. These studies demonstrate that aflibercept is an effective treatment for AMD, with the every-2-month regimen offering the potential to reduce the risk from monthly intravitreal injections and the burden of monthly monitoring. FINANCIAL DISCLOSURE(S) Proprietary or commercial disclosure may be found after the references.


British Journal of Ophthalmology | 2014

Guidelines for the management of neovascular age-related macular degeneration by the European Society of Retina Specialists (EURETINA)

Ursula Schmidt-Erfurth; Victor Chong; Anat Loewenstein; Michael Larsen; Eric H. Souied; Reinier O. Schlingemann; Bora Eldem; Jordi Monés; G. Richard; Francesco Bandello

Age-related macular degeneration (AMD) is still referred to as the leading cause of severe and irreversible visual loss world-wide. The disease has a profound effect on quality of life of affected individuals and represents a major socioeconomic challenge for societies due to the exponential increase in life expectancy and environmental risks. Advances in medical research have identified vascular endothelial growth factor (VEGF) as an important pathophysiological player in neovascular AMD and intraocular inhibition of VEGF as one of the most efficient therapies in medicine. The wide introduction of anti-VEGF therapy has led to an overwhelming improvement in the prognosis of patients affected by neovascular AMD, allowing recovery and maintenance of visual function in the vast majority of patients. However, the therapeutic benefit is accompanied by significant economic investments, unresolved medicolegal debates about the use of off-label substances and overwhelming problems in large population management. The burden of disease has turned into a burden of care with a dissociation of scientific advances and real-world clinical performance. Simultaneously, ground-breaking innovations in diagnostic technologies, such as optical coherence tomography, allows unprecedented high-resolution visualisation of disease morphology and provides a promising horizon for early disease detection and efficient therapeutic follow-up. However, definite conclusions from morphologic parameters are still lacking, and valid biomarkers have yet to be identified to provide a practical base for disease management. The European Society of Retina Specialists offers expert guidance for diagnostic and therapeutic management of neovascular AMD supporting healthcare givers and doctors in providing the best state-of-the-art care to their patients. Trial registration number NCT01318941.


Retina-the Journal of Retinal and Vitreous Diseases | 2012

High prevalence of sleep disordered breathing in patients with diabetic macular edema.

Rebecca H. Mason; Sophie West; Christine A. Kiire; Dawn C. Groves; Helen J. Lipinski; Alyson Jaycock; Victor Chong; John Stradling

Background: Diabetic retinopathy is more common and severe in patients with sleep disordered breathing (SDB). This study aimed to establish whether this is also true for patients with diabetic clinically significant macular edema (CSME). It is hypothesized that SDB, through intermittent hypoxia and blood pressure oscillations, might provoke worsening of CSME. Methods: Patients with CSME had a home sleep study (ApneaLink; ResMed) to identify SDB. These results were compared with relevant control populations. Macular thickness was measured using optical coherence tomography, and retinal photographs were graded to assess the severity of retinopathy. Results: Eighty of 195 patients (40 men) consented, with average age of 64.7 (11.7) years, neck circumference of 40.4 (5.4) cm, body mass index of 30.2 (6.2) kg/m2, glycosylated hemoglobin (HbA1c) 7.8% (1.4%) [62 (8.0) mmol/mol], and Epworth sleepiness scale of 7.4 (4.8). Overall, 54% had an oxygen desaturation index ≥10, and 31% had an apnea-hypopnea index ≥15. This SDB prevalence is probably higher than would be expected from the available matched control data. Those with SDB were not sleepier, but they were older and more obese. No significant relationship was identified between the degree of macular thickness and the severity of SDB. Conclusion: Individuals with CSME have a high prevalence of SDB. Sleep disordered breathing may contribute to the pathophysiology of CSME, but the mechanism remains unclear. Given the high prevalence, retinal specialists should perhaps consider a diagnosis of SDB in patients with CSME.


Ophthalmologica | 2012

Biological, Preclinical and Clinical Characteristics of Inhibitors of Vascular Endothelial Growth Factors

Victor Chong

Vascular endothelial growth factor (VEGF) plays an important role in the pathophysiology of several sight-threatening retinal disorders such as age-related macular degeneration, diabetic macular edema and proliferative diabetic retinopathy. The discovery of anti-VEGF agents has revolutionized our treatment of these conditions. There are 4 anti-VEGF agents that are either approved or in common use in ophthalmology, namely pegaptanib (Macugen, Pfizer), ranibizumab (Lucentis, Novartis), aflibercept or VEGF Trap-Eye (EYLEA, Bayer) and bevacizumab (Avastin, Roche). There are differences between them. In this review, the differences are discussed in detail. Furthermore, an attempt is made to explain some of the clinical trial data based on their differences in ocular efficacy, duration of action, and local and systemic safety concerns.


Respiration | 2012

Visual improvement following continuous positive airway pressure therapy in diabetic subjects with clinically significant macular oedema and obstructive sleep apnoea: proof of principle study.

Rebecca H. Mason; Christine A. Kiire; Dawn C. Groves; Helen J. Lipinski; Alyson Jaycock; Barbara Winter; Lewis Smith; Anne Bolton; Najib M. Rahman; R. Swaminathan; Victor Chong; John Stradling

Background: Diabetic retinopathy and diabetic macular oedema are more prevalent in patients with coexistent obstructive sleep apnoea (OSA). Objectives: We assessed if treatment of OSA with continuous positive airway pressure (CPAP) might improve visual acuity (VA). Methods: A total of 35 patients with clinically significant macular oedema (CSMO) and OSA [oxygen desaturation index (ODI) ≥10 or apnoea-hypopnoea index (AHI) ≥15] were identified and agreed to be studied. VA (expressed as the logarithm of the minimum angle of resolution, logMAR), macular thickness, fundal photographs, glycosylated haemoglobin (HbA1c) and rhodopsin mRNA were measured twice at baseline and at 3 and 6 months post-CPAP. Fluorescein angiography and the Epworth Sleepiness Scale (ESS) were obtained once at baseline and at 6 months. Results: Three patients withdrew before the first trial visit. Thus, a total of 32 patients (17 males) entered the study, and 4 subsequently withdrew; thus 28 completed 6 months of follow-up. Baseline characteristics of the subjects were as follows [mean (SD or inter-quartile range)]: age 66.2 (7.1) years, body mass index 31.7 (6.3), HbA1c 7.4% (1.44) [57.1 (15.7) mmol/mol], AHI 16.5 (11–25), ODI 16.0 (12–25), ESS 6.5 (4.0–12.0) and duration of diabetes 9.5 years (5.0–16.5). Participants were divided into 13 high and 15 low CPAP compliers (≥ and <2.5 h/night over the 6 months, respectively). At 6 months, the adjusted treatment effect on VA of high compliance versus low compliance was 0.11 (95% confidence interval 0.21 to –0.002; p = 0.047), equivalent to a one-line improvement on the logMAR chart. There was no significant improvement in macular oedema or fundal photographs. Conclusions: This hypothesis-generating, uncontrolled study suggests that ≥2.5 h/night CPAP usage over 6 months in individuals with CSMO and OSA may be associated with improvement in VA. This provides justification for a randomised controlled trial of CPAP therapy in such patients.


Ophthalmology | 2015

Improvement in Vision-Related Function with Intravitreal Aflibercept: Data from Phase 3 Studies in Wet Age-Related Macular Degeneration

Mitsuko Yuzawa; Kyoko Fujita; Kim Wittrup-Jensen; Christiane Norenberg; Oliver Zeitz; K. Adachi; E.C.Y. Wang; Jeffrey S. Heier; Peter K. Kaiser; Victor Chong; Jean François Korobelnik

PURPOSE To evaluate the effect of intravitreal aflibercept injection on visual function in wet age-related macular degeneration (AMD). DESIGN Prospective, multicenter, double-masked, active-controlled, parallel-group, randomized phase 3 clinical studies (VEGF Trap-Eye: Investigation of Efficacy and Safety in Wet AMD [VIEW] 1 and 2 [clinicaltrials.gov identifiers, NCT00509795 and NCT00637377, respectively]). PARTICIPANTS Patients (n=2419) with active, treatment-naïve, exudative AMD. This analysis included patients who received intravitreal aflibercept 2.0 mg every 8 weeks (2q8; n=607) or ranibizumab 0.5 mg every 4 weeks (0.5q4; n=595). INTERVENTION Patients were randomized 1:1:1:1 to receive intravitreal aflibercept 2q8 (after 3 initial monthly doses), intravitreal aflibercept 2q4, intravitreal aflibercept 0.5q4, or ranibizumab 0.5q4 in the study eye. Patients in the intravitreal aflibercept 2q8 group received a sham injection alternating with active treatment. MAIN OUTCOME MEASURES The 25-item National Eye Institute Visual Function Questionnaire (NEI VFQ-25) was administered at baseline and at weeks 12, 24, 36, and 52. The NEI VFQ-25 subscale scores were compared between intravitreal aflibercept 2q8 and ranibizumab 0.5q4 treatment arms, the approved dosing for each agent worldwide. Change in composite NEI VFQ-25 score was evaluated based on categorical change in visual acuity (worsened, unchanged, improved). RESULTS Baseline NEI VFQ-25 scores were similar for both treatments in both studies. Mean change from baseline to 52 weeks was similar for ranibizumab 0.5q4 and intravitreal aflibercept 2q8 across all 12 subscales, with the greatest improvements noted for mental health and general vision (9.0-11.6 points, both treatments, both studies). Improvement of 4 points or more (both treatments, both studies) also was observed for subscales near vision, distance vision, role difficulties, and dependency. Mean change from baseline to 52 weeks in NEI VFQ-25 composite score (pooled data) stratified by clinical response showed meaningful improvement only in patients who gained 5 Early Treatment Diabetic Retinopathy letters or more (7.3 and 7.8 points for intravitreal aflibercept 2q8 and ranibizumab 0.5q4, respectively). CONCLUSIONS Visual function outcomes were similar across all NEI VFQ-25 subscales over 52 weeks for intravitreal aflibercept 2q8 and ranibizumab 0.5q4, with clinically meaningful improvement recorded in 6 of 12 subscales.


British Journal of Ophthalmology | 2015

Efficacy and safety of intravitreal aflibercept injection in wet age-related macular degeneration: outcomes in the Japanese subgroup of the VIEW 2 study

Yuichiro Ogura; Hiroko Terasaki; Fumi Gomi; Mitsuko Yuzawa; Tomohiro Iida; Miki Honda; Koichi Nishijo; Olaf Sowade; Tetsushi Komori; Ursula Schmidt-Erfurth; Christian Simader; Victor Chong

Background/aims To evaluate efficacy and safety of intravitreal aflibercept (IVT-AFL) in Japanese patients with wet age-related macular degeneration (wAMD) from the VIEW 2 trial. Methods In this double-masked study, patients were randomised to: 0.5 mg IVT-AFL every 4 weeks (0.5q4); 2 mg IVT-AFL every 4 weeks (2q4); 2 mg IVT-AFL every 8 weeks (2q8) after 3 monthly injections; or 0.5 mg ranibizumab every 4 weeks (Rq4). Main efficacy outcomes included vision maintenance and best-corrected visual acuity (BCVA) at week 52. Results At week 52, all Japanese patients in the IVT-AFL groups (n=70) maintained vision, compared with 96% of Japanese patients (n=23/24) treated with ranibizumab. Japanese patients in all treatment groups showed improvement in BCVA after treatment. The Rq4, 2q4 and 2q8 groups experienced similar gains in BCVA from baseline. The 0.5q4 group had higher gains due to an unexpected drop in BCVA between screening and baseline. Central retinal thickness and mean area of choroidal neovascularisation decreased in all treatment groups with similar magnitude. Ocular treatment-emergent adverse events were balanced across treatment groups. Conclusions IVT-AFL was effective and well tolerated in Japanese patients. Outcomes in this population were consistent with those in the overall VIEW 2 population. Trial registration number NCT00637377.


British Journal of Ophthalmology | 2014

Improving the cost-effectiveness of photographic screening for diabetic macular oedema: a prospective, multi-centre, UK study.

Gordon Prescott; Peter F. Sharp; Keith A Goatman; Graham Scotland; Alan Fleming; Sam Philip; Roger T. Staff; Cynthia Santiago; Shyamanga Borooah; Deborah Broadbent; Victor Chong; Paul Dodson; Simon P. Harding; Graham P. Leese; Roly Megaw; Caroline Styles; Ken Swa; Helen Wharton; John A. Olson

Background/aims Retinal screening programmes in England and Scotland have similar photographic grading schemes for background (non-proliferative) and proliferative diabetic retinopathy, but diverge over maculopathy. We looked for the most cost-effective method of identifying diabetic macular oedema from retinal photographs including the role of automated grading and optical coherence tomography, a technology that directly visualises oedema. Methods Patients from seven UK centres were recruited. The following features in at least one eye were required for enrolment: microaneurysms/dot haemorrhages or blot haemorrhages within one disc diameter, or exudates within one or two disc diameters of the centre of the macula. Subjects had optical coherence tomography and digital photography. Manual and automated grading schemes were evaluated. Costs and QALYs were modelled using microsimulation techniques. Results 3540 patients were recruited, 3170 were analysed. For diabetic macular oedema, Englands scheme had a sensitivity of 72.6% and specificity of 66.8%; Scotlands had a sensitivity of 59.5% and specificity of 79.0%. When applying a ceiling ratio of £30 000 per quality adjusted life years (QALY) gained, Scotlands scheme was preferred. Assuming automated grading could be implemented without increasing grading costs, automation produced a greater number of QALYS for a lower cost than Englands scheme, but was not cost effective, at the studys operating point, compared with Scotlands. The addition of optical coherence tomography, to each scheme, resulted in cost savings without reducing health benefits. Conclusions Retinal screening programmes in the UK should reconsider the screening pathway to make best use of existing and new technologies.


Health Technology Assessment | 2013

Improving the economic value of photographic screening for optical coherence tomography-detectable macular oedema: a prospective, multicentre, UK study

J. Olson; Peter F. Sharp; Keith A Goatman; Gordon Prescott; Graham Scotland; Alan Fleming; Sam Philip; C. Santiago; Shyamanga Borooah; Deborah Broadbent; Victor Chong; Paul Dodson; Sophie Harding; Graham P. Leese; Caroline Styles; K. Swa; H. Wharton

OBJECTIVES To determine the best photographic surrogate markers for detecting sight-threatening macular oedema (MO) in people with diabetes attending UK national screening programmes. DESIGN A multicentre, prospective, observational cohort study of 3170 patients with photographic signs of diabetic retinopathy visible within the macular region [exudates within two disc diameters, microaneurysms/dot haemorrhages (M/DHs) and blot haemorrhages (BHs)] who were recruited from seven study centres. SETTING All patients were recruited and imaged at one of seven study centres in Aberdeen, Birmingham, Dundee, Dunfermline, Edinburgh, Liverpool and Oxford. PARTICIPANTS Subjects with features of diabetic retinopathy visible within the macular region attending one of seven diabetic retinal screening programmes. INTERVENTIONS Alternative referral criteria for suspected MO based on photographic surrogate markers; an optical coherence tomographic examination in addition to the standard digital retinal photograph. MAIN OUTCOME MEASURES (1) To determine the best method to detect sight-threatening MO in people with diabetes using photographic surrogate markers. (2) Sensitivity and specificity estimates to assess the costs and consequences of using alternative strategies. (3) Modelled long-term costs and quality-adjusted life-years (QALYs). RESULTS Prevalence of MO was strongly related to the presence of lesions and was roughly five times higher in subjects with exudates or BHs or more than two M/DHs within one disc diameter. Having worse visual acuity was associated with about a fivefold higher prevalence of MO. Current manual screening grading schemes that ignore visual acuity or the presence of M/DHs could be improved by taking these into account. Health service costs increase substantially with more sensitive/less specific strategies. A fully automated strategy, using the automated detection of patterns of photographic surrogate markers, is superior to all current manual grading schemes for detecting MO in people with diabetes. The addition of optical coherence tomography (OCT) to each strategy, prior to referral, results in a reduction in costs to the health service with no decrement in the number of MO cases detected. CONCLUSIONS Compared with all current manual grading schemes, for the same sensitivity, a fully automated strategy, using the automated detection of patterns of photographic surrogate markers, achieves a higher specificity for detecting MO in people with diabetes, especially if visual acuity is included in the automated strategy. Overall, costs to the health service are likely to increase if more sensitive referral strategies are adopted over more specific screening strategies for MO, for only very small gains in QALYs. The addition of OCT to each screening strategy, prior to referral, results in a reduction in costs to the health service with no decrement in the number of MO cases detected. STUDY REGISTRATION This study has been registered as REC/IRAS 07/S0801/107, UKCRN ID 9063 and NIHR HTA 06/402/49. SOURCE OF FUNDING This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 17, No. 51. See the HTA programme website for further project information.


Retina-the Journal of Retinal and Vitreous Diseases | 2014

Understanding Indocyanine Green Angiography In Polypoidal Choroidal Vasculopathy: The Group Experience With Digital Fundus Photography and Confocal Scanning Laser Ophthalmoscopy

Chui Ming Gemmy Cheung; Timothy Y. Y. Lai; Shih-Jen Chen; Victor Chong; Won Ki Lee; Hla Myint Htoon; Wei Yan Ng; Yuichiro Ogura; Tien Yin Wong

Purpose: To evaluate the angiographic features in using fundus camera–based versus confocal scanning laser ophthalmoscope (cSLO)-based indocyanine green angiography in differentiating polypoidal choroidal vasculopathy (PCV) from typical age-related macular degeneration. Methods: Sixty-five eyes of 44 patients with exudative maculopathy due to PCV or typical age-related macular degeneration were prospectively imaged with indocyanine green angiography using fundus camera and cSLO. Images were graded independently by retinal specialists. The main outcome measure was agreement between cSLO and fundus camera for the diagnosis of PCV. The rate of detection and area under the receiver operating characteristic curve of 7 preselected individual features were also compared. Results: The diagnosis of PCV was made with the cSLO system in 36 eyes (55.4%) and typical age-related macular degeneration in 29 eyes (44.6%), whereas the fundus camera diagnosed PCV in 39 eyes (60.0%) and typical age-related macular degeneration in 26 eyes (40.0%). There was moderate agreement between the two indocyanine green angiography systems (Kappa = 0.53). Using cSLO as the gold standard, fundus camera has a sensitivity and specificity of 83.3% and 69.0%, respectively. Typical nodular appearance was the most commonly detected feature (median, 88.9% for cSLO, 80.6% for fundus camera, P = 0.63) and had the highest area under the curve for the diagnosis of PCV in both systems (median, 80.2% for cSLO, 73.2% for fundus camera, P = 0.13). Confocal scanning laser ophthalmoscope was more sensitive in detecting branching vascular network and late hyperfluorescent plaque. Conclusion: Both systems detected >80% of PCV based on typical nodular appearance of polyps. However, the cSLO is superior in detecting additional features, particularly branching vascular network.

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