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==== Dexeneración macular relacionada coa idade neovascular ====
[[Ranibizumab]], aé monoclonalun antibodyfragmento fragmentde anticorpo monoclonal (Fab) derivedderivado fromdo [[bevacizumab]], hasque beenfoi developeddesenvolvido bypor Genetech forpara intraocularo useseu uso intraocular. InEn 2006, a FDA approvedaprobou theo drugfármaco forpara theo treatmenttratamento of neovascularde [[age-relateddexeneración macular degenerationrelacionada coa idade]] (wetneovascular (AMD húmida). TheO drugfármaco hadsometérase undergone threea successfultres clinicalensaios trialsclínicos bydesde thenentón.<ref name="FDA2006">{{Cite journal|title=FDA Approves New Biologic Treatment for Wet Age-Related Macular Degeneration |journal=FDA News & Events |date = June 30, 2006 |url=http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/2006/ucm108685.htm | accessdate = 17 April 2013 }}</ref>
In the OctoberEn 2006 issuepublicouse ofque theas Newinxeccións Englandintravitreais Journalmensuais ofde Medicineranibizumab (NEJM),levaron Rosenfield,a etun al.incremento reportedsignificativo thatnivel monthlyda intravitrealagudeza injectionvisula ofmedia ranibizumabcomparada ledco todunha significantinxección increasesimulada. inChegouse theá levelconclusión ofno meanestudo visualde acuitydous comparedanos toen that of sham injection. It was concluded from the two-year, phasefase III studyque thato ranibizumab isé verymoi effectiveefectivo inno thetratamento treatmentda ofAMD minimallyminimamente classicclásica (MC) orou occultAMD wethúmida AMDoculta (age-related [[maculardexeneración degenerationmacular]] relacionada coa idade) withcon lowtaxas ratesbaixas ofde ocularefectos adverseadversos effectsoculares.<ref name="pmid=19118696">{{cite journal |last1=Brown |first1=David M. |last2=Michels |first2=Mark |last3=Kaiser |first3=Peter K. |last4=Heier |first4=Jeffrey S. |last5=Sy |first5=Judy P. |last6=Ianchulev |first6=Tsontcho |last7=Anchor Study |first7=Group |title=Ranibizumab versus Verteporfin Photodynamic Therapy for Neovascular Age-Related Macular Degeneration: Two-Year Results of the ANCHOR Study |journal=Ophthalmology |volume=116 |issue=1 |pages=57–65 |year=2009 |pmid=19118696 |doi=10.1016/j.ophtha.2008.10.018}}</ref>
AnotherOutro studyestudo publishedpublicado in the Januaryen 2009 issue of Ophthalmology provides the evidenceproporciona forprobas theda efficacyeficacia ofdo ranibizumab. Brown,A etinxecciónn al. reported that monthly intravitrealintravítrea injectionmensual ofde ranibizumab ledcausa toun significantincremento increasesignificativo inno thenivel levelde ofagudeza meanvisula visualmedia acuitycomparado comparedco to that ofda [[photodynamicterapia therapyfotodinámica]] withcon [[verteporfinverteporfina]]. ItA wasconclusión concludeddo fromestudo thede twodous year,anos phaseen fase III studyfoi que thato ranibizumab wasera superior toá photodynamicterapia therapyfotodinámica withcon verteporfinverteporfina inno thetratamento treatmentda ofAMD predominantlyhúmida classicpredominantemente clásica (PC) Wet AMD withcon lowtaxs ratesbaixas ofde ocularefectos adverseadversos effectsoculares.<ref name="pmid=17021318">{{cite journal |last1=Rosenfeld |first1=Philip J. |last2=Brown |first2=David M. |last3=Heier |first3=Jeffrey S. |last4=Boyer |first4=David S. |last5=Kaiser |first5=Peter K. |last6=Chung |first6=Carol Y. |last7=Kim |first7=Robert Y. |last8=Marina Study |first8=Group |title=Ranibizumab for Neovascular Age-Related Macular Degeneration |journal=New England Journal of Medicine |volume=355 |issue=14 |pages=1419–31 |year=2006 |pmid=17021318 |doi=10.1056/NEJMoa054481}}</ref>
Porén, o custo/efectividade do ranibizumab é cuestionado debido o seu enorme prezo. Cada inxección costa 2 millóns de dólares e deben administrarse mensualmente. Unha alternativa moito máis barata é o bevaciazumab.
Although the efficacy of ranibizumab is well-supported by extensive clinical trials,{{Citation needed|date=June 2011}} the cost effectiveness of the drug is questioned. Since the drug merely stabilizes patient conditions, ranibizumab must be administered monthly. At a cost of $2,000.00 per injection, the cost to treat wet AMD patients in the United States is greater than $10.00 billion per year. Due to high cost, many ophthalmologists have turned to bevacizumab as the alternative intravitreal agent in the treatment of wet AMD. The drug costs $15.00 to 50.00 in the United States.
InEn 2007, Rafterypublicouse que, eta al.menos reportedque in the British Journal of Ophthalmology that, unlesso ranibizumab issexa 2.,5 timesveces moremáis effectiveefectivo theque o bevacizumab, o ranibizumab isnos notten cost-effective.un Itbeneficio wascusto/efectividade. concludedConcluíuse thatque theo priceprezo ofdo ranibizumabfármaco wouldtería haveque toser bereducido drasticallydrasticamente reducedpara forque thepuidese drugter toun bebeneficio cost-effectivecusto/efectividade.<ref name="pmid=1743101">{{cite journal |last1=Raftery |first1=J. |last2=Clegg |first2=A. |last3=Jones |first3=J. |last4=Tan |first4=S. C. |last5=Lotery |first5=A. |title=Ranibizumab (Lucentis) versus bevacizumab (Avastin): modelling cost effectiveness |journal=British Journal of Ophthalmology |volume=91 |issue=9 |pages=1244–6 |year=2007 |pmid=17431015 |pmc=1954941 |doi=10.1136/bjo.2007.116616}}</ref>
En 2012, o tratamento anti-VEGF con Avastin foi aceptado por Medicare, é ten un prezo e eficacia razoables. Lucentis ten unha estrutura similar pero máis pequena que a Avastin, e está aprobado pola FDA pero é máis caro, como tamén o é EYLEA (aflibercept). Están a realizarse ensaios comparativos sobre a efcicacia destes tratamentos.
[[Off-label use]] of intravitreal bevacizumab has become a widespread treatment for neovascular age-related macular degeneration.<ref>[http://patentdocs.typepad.com/patent_docs/2007/10/genentech-acts-.html Patent Docs: Genentech Acts to Halt Off-label Use of Avastin® for Age-related Macular Degeneration<!-- Bot generated title -->]</ref> Although the drug is not FDA-approved for non-oncologic uses, some studies{{Which|date=June 2011}} suggest that bevacizumab is effective in increasing visual acuity with low rates of ocular adverse effects. However, due to small sample size and lack of randomized control trial, the result is not conclusive.
== Efectos neurolóxicos do VEGF durante o exercicio ==
In October 2006, the National Eye Institute (NEI) of the National Institutes of Health (NIH) announced that it would fund a comparative study trial of ranibizumab and bevacizumab to assess the relative efficacy and ocular adversity in treating wet AMD. This study, called the Comparison of Age-Related Macular Degeneration Treatment Trials (CATT Study), will enroll about 1,200 patients with newly diagnosed wet AMD, randomly assigning the patients to different treatment groups.{{Citation needed|date=June 2011}}
A hipoxia regula á alza fortemente a expresión de VEGF e este exerce un efecto neuroprotector sobre as neuronas hipóxicas.<ref name="NHM IGF-1 VEGF" /> O exercicio aeróbico incrementa a biosíntese de VEGF nos tecidos periféricos, que despois cruza a [[barreira hematoencefálica]] e promove a neuroxénese e anxioxénese no [[sistema nervioso central]].<ref name="Cerebral hemodynamics and AD">{{cite journal | vauthors = Tarumi T, Zhang R | title = Cerebral hemodynamics of the aging brain: risk of Alzheimer disease and benefit of aerobic exercise | journal = Front Physiol | volume = 5 | issue = | pages = 6 | date = January 2014 | pmid = 24478719 | pmc = 3896879 | doi = 10.3389/fphys.2014.00006 | quote = Exercise-related improvements in brain function and structure may be conferred by the concurrent adaptations in vascular function and structure. Aerobic exercise increases the peripheral levels of growth factors (e.g., BDNF, IFG-1, and VEGF) which cross the blood-brain barrier (BBB) and stimulate neurogenesis and angiogenesis (Trejo et al., 2001; Lee et al., 2002; Fabel et al., 2003; Lopez-Lopez et al., 2004).}}</ref><ref name="Fitness mechanism" /><ref name="VEGF aging brain">{{cite journal | vauthors = Bouchard J, Villeda SA | title = Aging and brain rejuvenation as systemic events | journal = J. Neurochem. | volume = 132 | issue = 1 | pages = 5–19 | year = 2015 | pmid = 25327899 | pmc = 4301186 | doi = 10.1111/jnc.12969 }}</ref> Os incrementos inducidos polo exercicio na sinalización por VEGF melloran o volume sanguíneo cerebral e contribúen á neuroxénese inducida polo exercicio no [[hipocampo]].<ref name="Comprehensive review" /><ref name="Fitness mechanism" /><ref name="VEGF aging brain" />
By May 2012, anti-VEGF treatment with Avastin has been accepted by Medicare, is quite reasonably priced, and effective. Lucentis has a similar but smaller molecular structure to Avastin, and is FDA-approved (2006) for treating MacD, yet remains more costly, as is the more recent (approved in 2011) EYLEA (aflibercept). Tests on these treatments are ongoing relative to the efficacy of one over another.
== Notas ==
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