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Studies evaluate Viagra risk for optic neuropathy Howard D Pomeranz
Rachel E Sobel
only two (five per cent) patients recovered in Fort Lauderdale, Florida vision.The vision outcome was unknown inthe remaining two (five per cent) men.
A REVIEW of reports of optic neuropathy "Reports of optic neuropathy in men occurring in men being treated for erectile treated with PDE-5 inhibitors are rare, but dysfunction with a phosphodiesterase-5 sildenafil accounts for about one-fifth of all (PDE-5) inhibitor highlight there is a of the reports received by the FDA of potential for those drugs to cause this drug-associated ischemic optic neuropathy.
serious ocular adverse event and even Despite the limitations of this review, we permanent vision loss, say investigators believe the information demonstrates there from the Research on Adverse Events and is the potential for serious ocular toxicity Reports (RADAR) project.
associated with PDE-5 inhibitor treatment, However, analyses based on particularly considering the cases where approximately 52,000 patient years of men noticed symptom onset soon after observation collected in clinical and first using these drugs.That conclusion also observational studies demonstrate that the seems consistent with the decision by the incidence of nonarteritic anterior ischemic FDA that the product labelling for PDE-5 optic neuropathy (NAION) among men inhibitors include information on reports of receiving the PDE-5 inhibitor sildenafil NAION temporally associated with use of (Viagra, Pfizer) is no higher than the rate those medications," said Howard D occurring in the general population, Pomeranz, MD, PhD, on behalf of the according to findings reported by Alan M RADAR group. Dr Pomeranz is clinical Laties, MD, G Scheie research professor of associate professor of ophthalmology, New ophthalmology, Scheie Eye Institute, York University, New York, and specialises in University of Pennsylvania Medical School, neuro-ophthalmology at the North Shore- Philadelphia, and co-authors from Pfizer.
Long Island Jewish Health System.
The two reviews examining PDE-5 inhibitor-associated optic neuropathy werepresented at the annual meeting of ARVO.
"Reports of optic The RADAR analysis covered the years 1998 to 2005. It examined reports in the neuropathy in men treated published literature and from the UnitedStates Food and Drug Administration's with PDE-5 inhibitors are (FDA) MedWatch program that describedclinical characteristics of optic neuropathy rare, but sildenafil occurring in men treated with sildenafil ortadalafil (Cialis, Lilly ICOS). Cases were accounts for about one- included in the analysis only if they fifth of all of the reports contained clinical information indicating thedevelopment of optic disc oedema, visual received by the FDA of field defects, optic disc atrophy, optic dischaemorrhages, afferent pupillary defect, Courtesy of Rachel E Sobel MPH drug-associated ischemic and/or change in visual acuity or visionblurring.
optic neuropathy" A total of 39 unique cases were neuropathy or optic neuropathy each Dr Pomeranz noted that in addition to identified. Only the literature report was Howard D Pomeranz MD,PhD
accounted for about half of the remaining the problem of incomplete reporting, included if there were duplicate reports cases. A single case was described as another limitation of this review is that it from the two sources. Information was "The data should also remind posterior ischemic optic neuropathy.
provides no information on the incidence often missing on the duration of treatment ophthalmologists and other eye care The findings in nearly all patients included of sildenafil- or tadalafil-associated optic (54 per cent) and interval between drug professionals to get a careful drug history decrease in visual acuity or vision blurring ingestion and presentation (33 per cent).
when they diagnose ischemic optic (85 per cent).Visual field defects (59 per "We do not know the denominator for However, among the cases where the data neuropathy with the aim of identifying PDE- cent) and optic disc oedema (54 per cent) calculating an incidence rate that would was available, the duration of PDE-5 5 inhibitor-associated cases that can be were also prominent ophthalmologic allow us to put the risk of NAION into inhibitor use ranged from a single dose to added to the existing pool. In addition, they features, while 14 patients (36 per cent) perspective. However, we are trying to more than one year.Time to onset of visual should remember to advise men who were reported to present with an afferent identify approaches that could be used to symptoms was within 48 hours in 22 (85 develop this complication in one eye that pupillary defect and optic disc haemorrhage investigate that important issue," Dr per cent) of the 26 men where that the fellow eye may be at risk with was reported in 11 patients (28 per cent).
Pomeranz said.
information was reported, but potentially continued use of a PDE-5 inhibitor." However, Dr Pomeranz observed that He noted one possibility under ranged up to one month.
The 39 patients included in the review relative to the cases described in the exploration would be to analyse data from The affected eye(s) was unknown in 15 ranged in age from 34 to 76 years old, with literature, those reported to the FDA the computerised medical records system per cent of cases. Among the cases with a median of 61.5 years. Sildenafil accounted contained much less detailed information.
of the US Veterans Administration, that information available, the majority had for all of the 21 reports to MedWatch and "Whether submitted by a physician, the identifying men with a diagnosis of ischemic unilateral involvement (85 per cent), mostly for 15 of the 18 literature reports (83 per patient, or some other party, the optic neuropathy and those who received a affecting the right eye.
MedWatch reports are generally prescription for a PDE-5 inhibitor. He also Notably, 90 per cent of the 39 patients The adverse event was reported as incomplete and highlight the limitations of pointed out that attempts to estimate the suffered permanent loss of vision in one (77 NAION in the majority of cases (67 per spontaneous, passive reporting without potential risk of NAION should take into per cent) or both (13 per cent) eyes, while cent), while non-specified ischemic optic standardised examination," he said.
account individual susceptibility based on optic disc characteristics, ie, presence of the 50 years and older was about 2.5 cases per so-called ‘disc at risk'.
100,000 per year. A rate of 11.8 per "It is also clear that ED and NAION 100,000 men aged 50 or more per year share vascular risk factors so that the was reported by Hattenhauer and population of patients with ED may be at colleagues in an epidemiologic study increased risk for NAION relative to the determining the incidence of NAION general population.Those potential among residents of Olmsted County in Recent developments confounders need to also be controlled for when examining any association between "While there have been reports to the PDE-5 inhibitor treatment and NAION," FDA and in the published literature of in the vision care industry Dr Pomeranz said.
symptoms of NAION developing amongmen being treated with PDE-5 inhibitors,the incidence of that occurrence isunknown.These analyses show that in large "It is also clear that ED populations of patients receiving these Slowdown for ruboxistaurin
Perimeter.The new LD700 Perimeter will be drugs under careful surveillance, the built by Tinsley and marketed by Paradigm and NAION share vascular The US FDA told Eli Lilly and Company that apparent incidence of NAION does not it would not consider approving globally.The LD700 has already received US differ from that expected in the general risk factors so that the ruboxistaurin mesylate (Arxxant) without FDA approval and the CE mark. Paradigm population," said Dr Laties.
additional clinical trials.The FDA is asking said it also plans to launch an A- "The clinical trials provide an opportunity population of patients with Lilly to conduct an additional three-year Scan/Pachymeter, and two A/B Scan devices.
to reliably capture incident serious adverse study of the experimental oral treatment for events, and the epidemiologic assessments ED may be at increased diabetic retinopathy. Lilly was seeking an involving large numbers of individuals have indication for the treatment of moderate-to- Bausch develops plasmin options
considerable power. As such this analysis risk for NAION relative to severe nonproliferative diabetic retinopathy.
Bausch and Lomb received an exclusive provides an important framework for Ruboxistaurin is a specific inhibitor of PKC b, licence from Talecris Biotherapeutics to understanding the potential drug-related the general population" an enzyme that has been implicated in recombinant plasmin technology for use in risk that is very difficult to derive from retinopathy.The company said it would ophthalmology.The two companies co- Howard D Pomeranz MD,PhD
individual, spontaneous case reports, and it consider its options, but does not intend to developed rPlasmin, a recombinant derivative is a perspective that warrants attention." withdraw its new drug application. Earlier this of the human blood component plasmin.The "Pfizer takes product safety very year Lilly signed an agreement with Alcon to enzyme degrades many blood plasma Defining the incidence
seriously, so this analysis was performed to co-promote Arxxant in the US and Puerto proteins, including fibrin clots. Bausch believes better understand the potential risk of The data presented by Dr Laties was the technology has the potential to treat NAION in men treated with sildenafil. It derived from 103 Pfizer-sponsored sildenafil many conditions for which vitrectomy was reassuring to see that with more than global clinical trials and two European surgery is now used.The company says it is 44,800 men represented in the pooled observational, "real-life" studies – the Pfizer- AMO shipping new Tecnis
now developing plasma-derived plasmin for analysis, the occurrence of NAION was sponsored prospective International Men's AMO announced it had begun shipping the ocular indications. It is enrolling patients in found to be consistent with what would be Health Study (IMHS) and the Prescription new Tecnis CL silicone IOL in the US, Canada early-stage clinical trials to evaluate plasmin's expected among similarly aged men in the Event Monitoring (PEM) study that was and Asia.The company introduced the lens at therapeutic potential to relieve retinal general population," said Rachel E Sobel conducted independently by the Drug the XXIV Congress of the ESCRS in London.
traction.This agreement gives Bausch the MPH, associate director of epidemiology in Safety Research Unit at the University of This Tecnis CL replaces the Z9000 and opportunity to develop a next-generation safety and risk management, Pfizer, New Z9001 Tecnis silicone IOL models.The recombinant version. Bausch agreed to make The 103 Pfizer-sponsored studies company says the new IOL has blue-modified milestone payments based on the included open-label and double-blind trials C PMMA haptics that provide better visibility development and registration progress as enrolling more than 13,400 men (13,000 "It was reassuring to see and easier implantation of the lens. It also has well as pay ongoing royalties based on patient-years of observation) treated for a frosted OptiEdge design, which is said to product sales.
ED with sildenafil between 1993 and 2003.
that with more than reduce edge glare and posterior capsule The IMHS, which was conducted in opacification.The new IOL is already available Germany, France, Spain, and Sweden, 44,800 men represented in in Europe and will be marketed in Japan next New blade box from Schwind
contributed data on more than 3,800 men Schwind eye-tech-solutions has developed a with nearly 3,000 patient-years of follow-up the pooled analysis, the blade box for the Carriazo-Pendular who received a prescription for sildenafil microkeratome that it says will provide between 2001 and 2004. From 1998 to occurrence of NAION was Pfizer expands AMD research
enhanced safety during treatment.The blade 2001, more than 28,000 men prescribed Pfizer reached an agreement with Quark is guided and protected during insertion and sildenafil through the United Kingdom's found to be consistent Biotech to acquire an exclusive worldwide removal without coming into contact with National Health Service were followed in with what would be license to Quark's novel human gene RTP- the surgeon, thus avoiding the risk of injuries two cohorts for the PEM.The PEM 801 and to molecules that modify its and complications, the company says.
contributed about 35,500 patient-years of expected among similarly expression or function. RTP-801 is involved observation to the analysis.
in the development of pathologic blood Review for suspected or diagnosed aged men in the general vessels that accelerate the progression of Gene therapy in the works
incident cases of NAION during sildenafil age-related macular degeneration. Financial Edison Pharma announced a collaborative treatment identified a single affected patient terms of the agreement were not agreement with Brazil's Institute of Vision to in the PEM, while there were no cases develop gene-based treatments for Leber's among men in the industry-sponsored Rachel E Sobel MPH
hereditary optic neuropathy (LHON).The clinical trials or the IMHS. Across the entire disease arises from impairments in energy PEM study, the unadjusted incidence rate of The single case of NAION identified in Da Vinci femto laser renamed
production in the eye and is caused by NAION was 2.8 cases per 100,000 patient- the PEM involved a 61-year-old patient who Ziemer has renamed its femtosecond genetic defects in the mitochondria.A years of sildenafil use. Restricting the had multiple other risk factors for NAION, surgical laser, formerly known as the Da worldwide research consortium is involved analysis to only the second cohort of men including age over 50 years old and a Vinci.The laser will now be known as in developing gene-based therapies for in the PEM where the case of NAION history of smoking, hypertension, "Ziemer's Femto" Laser Device, model inherited mitochondrial diseases. LHON is an occurred, the incidence rate was similar at hyperlipidemia, and ischemic heart disease, number LDV-3.This change was made attractive target because researchers have 3.0 cases per 100,000 patient-years.
including a prior myocardial infarction. He because of trademark issues.
identified the genes believed responsible for Dr Laties observed those calculated rates was also taking multiple other medications the disorder.Although LHON is quite rare, compare favourably with literature reports and had been using sildenafil for over a year New compact perimetry tool
researchers believe that developing a of the incidence of NAION among men before experiencing symptoms of NAION.
Paradigm Medical announced an agreement treatment for that disease could advance the aged 50 years and older. In a population- with the Tinsley company, a division of search for treatments for more common based study including men and women in Hartest Precision Instruments Ltd., regarding retinal diseases.
Missouri and Los Angeles County, the development of a new-generation California, Johnson and Arnold estimated [email protected] compact Visual Field Screener (VFS) the incidence of NAION among men aged

Source: http://www.escrs.org/PUBLICATIONS/EUROTIMES/06Nov/pdf/StudiesevaluateViagra.pdf