Sobha Sivaprasad1, Philip Hykin. 1. Moorfields Eye Hospital, 162 City Road, London, UK. sobha.sivaprasad@moorfields.nhs.uk
Abstract
INTRODUCTION OR BACKGROUND: The hallmark of wet age-related macular degeneration (AMD) is choroidal neovascularization (CNV). The key cytokine involved in the pathogenesis of CNV is vascular endothelial growth factor (VEGF). Since 2005, antiVEGF therapy has revolutionized the management of this condition. SOURCES OF DATA: A systematic computerized literature search was conducted on PubMed (http://www.ncbi.nlm.nih.gov/pubmed/). AREAS OF AGREEMENT: AntiVEGF therapy has resulted in improvement in visual function and performance. Currently, practitioners are spoilt for choice of these agents. AREAS OF CONTROVERSY: Bevacizumab is unlicensed for intraocular use but has a better market share than ranibizumab in the treatment of wet AMD as it is approximately 40 times cheaper than ranibizumab, if aliquoted into smaller doses for intraocular use. This has stirred up questions on indemnity, safety, dosing, treatment regimen and quality control, despite the fact that well-designed clinical trials have shown that both drugs are equally effective. Another dilemma for the physicians is the choice of treatment regimens with antiVEGF agents that include fixed dosing, optical coherence tomography (OCT)-guided re-treatment, treat and extend or a combination of proactive and reactive dosing. Real-life outcomes of physician-dependent OCT-guided re-treatment with these agents are inferior to outcomes reported in clinical trials. GROWING POINTS: A recently food and drug administration-approved antiVEGF agent, aflibercept, is rapidly becoming a popular choice as well-designed randomized clinical trials indicate that eight weekly fixed dosing of aflibercept is non-inferior to monthly ranibizumab. AREAS TIMELY FOR DEVELOPING RESEARCH: Options for reducing the frequency of repeated intravitreal injections are being explored. Combination therapy with photodynamic therapy and epimacular brachytherapy seem scientifically plausible due to their synergistic effects. However, so far the results on these combinations have not shown any superior visual outcomes to antiVEGF monotherapy, and the practicalities of delivering these therapies are formidable. So, research into other novel therapeutic approaches such as pigment epithelium-derived factor and designed ankyrin repeat proteins are gaining momentum.
INTRODUCTION OR BACKGROUND: The hallmark of wet age-related macular degeneration (AMD) is choroidal neovascularization (CNV). The key cytokine involved in the pathogenesis of CNV is vascular endothelial growth factor (VEGF). Since 2005, antiVEGF therapy has revolutionized the management of this condition. SOURCES OF DATA: A systematic computerized literature search was conducted on PubMed (http://www.ncbi.nlm.nih.gov/pubmed/). AREAS OF AGREEMENT: AntiVEGF therapy has resulted in improvement in visual function and performance. Currently, practitioners are spoilt for choice of these agents. AREAS OF CONTROVERSY: Bevacizumab is unlicensed for intraocular use but has a better market share than ranibizumab in the treatment of wet AMD as it is approximately 40 times cheaper than ranibizumab, if aliquoted into smaller doses for intraocular use. This has stirred up questions on indemnity, safety, dosing, treatment regimen and quality control, despite the fact that well-designed clinical trials have shown that both drugs are equally effective. Another dilemma for the physicians is the choice of treatment regimens with antiVEGF agents that include fixed dosing, optical coherence tomography (OCT)-guided re-treatment, treat and extend or a combination of proactive and reactive dosing. Real-life outcomes of physician-dependent OCT-guided re-treatment with these agents are inferior to outcomes reported in clinical trials. GROWING POINTS: A recently food and drug administration-approved antiVEGF agent, aflibercept, is rapidly becoming a popular choice as well-designed randomized clinical trials indicate that eight weekly fixed dosing of aflibercept is non-inferior to monthly ranibizumab. AREAS TIMELY FOR DEVELOPING RESEARCH: Options for reducing the frequency of repeated intravitreal injections are being explored. Combination therapy with photodynamic therapy and epimacular brachytherapy seem scientifically plausible due to their synergistic effects. However, so far the results on these combinations have not shown any superior visual outcomes to antiVEGF monotherapy, and the practicalities of delivering these therapies are formidable. So, research into other novel therapeutic approaches such as pigment epithelium-derived factor and designed ankyrin repeat proteins are gaining momentum.
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