A federal lawsuit filed by James Thompson in the United States District Court for the Southern District of Texas seeks monetary damages for the loss of vision allegedly caused by the use of Viagra, Pfizer�s blockbuster erectile dysfunction (ED) drug. Mr. Thompson also seeks class- action certification on behalf of all other men injured by the drug.
The Food and Drug Administration has received over 40 reports of blindness in men taking Viagra, Levitra, or Cialis. This type of irreversible blindness known as non-arteritic anterior ischemic optic neuropathy (NAION) restricts the flow of oxygenated blood to the optic nerve.
Pfizer has taken the position that its drug does not cause NAION and that a class-action is inappropriate. The company claims that NAION shares a number of common risk factors with ED, including high blood pressure, diabetes, and high cholesterol.
The lawsuit charges that Pfizer failed to warn the public that taking Viagra could cause NAION.
Tuesday, March 18, 2008
Viagra Linked to Vision Problems FDA Studies Reports, Discusses Disclosure
An investigation into whether Viagra and other popular impotence drugs may cause permanent eye damage is unlikely to lead to a recall, federal officials and medical experts said Friday, but could prompt new warnings.
The Food and Drug Administration is looking into 38 reports of eye damage in men who took Viagra, four involving Cialis, and one with Levitra. About 30 million men worldwide have taken the drugs.
"We haven't been able to determine that there is a cause and effect due to the medication," FDA spokeswoman Suzanne Trevino said. "But we are taking it seriously."
Most of the men who suffered eye damage did not go completely blind but lost part of their vision in one eye. Complicating the FDA's investigation, many of the patients had other risk factors, such as high blood pressure, that would make them vulnerable to the particular kind of eye problem.
The condition nonarteritic anterior ischemic optic neuropathy, or NAION involves damage to the optic nerve caused by an interruption of blood supply.
Trevino said the FDA is talking with Pfizer Inc., Viagra's manufacturer, about formally disclosing the risk in its prescribing literature for doctors. Eli Lilly & Co., which makes Cialis, recently changed its information to acknowledge reports of eye damage.
Dr. Howard Pomeranz, a professor of ophthalmology at the University of Minnesota, reported a suspected link between Viagra and eye damage in a medical journal article published in March.
"This particular eye problem should be added to the list of side effects that patients have access to," Pomeranz said Friday. But, he added, the medical evidence at this point would not warrant withdrawing the drug.
"I'm not recommending that men stop taking this drug," he said. "It's very good for what it's prescribed for."
However, Pomeranz said, patients who already have NAION in one eye should be strongly cautioned about the risk of using Viagra. And any patient who experiences blurriness or a loss of peripheral vision should stop taking such medications and consult a doctor immediately.
For patients who want to know whether they may be at risk, an eye exam may help answer the question. Doctors say one risk factor for NAION is tightly bundled nerves and blood vessels in the back of the eye. An eye doctor can identify that condition.
Medical factors that increase the risk of NAION include high blood pressure, high cholesterol and diabetes. Older people also are more likely to have the problem.
Dr. Michael Lee, a neuro-ophthalmologist at the Cleveland Clinic Foundation, treated a 67-year-old architect who had received a sample pack of Cialis from his primary care doctor.
One morning, two hours after taking the drug, the patient noticed a blurry patch in the bottom of his field of vision in his right eye, Lee said. His vision recovered by the next morning.
The patient took the drug three more times, with the same effect. Then he took another dose. That time, the blurry patch did not go away. The damage was permanent, Lee said.
The patient had two risk factors for NAION: high cholesterol and an especially small channel for blood vessels that run through the optic nerve behind the eye.
NAION strikes fewer than 10 people out of every 100,000 over age 50, Lee said.
In a statement, Pfizer said there was no evidence that NAION occurred more frequently in men taking Viagra than in men of similar age and health who did not take the drug.
"Most of the reported cases in which NAION has occurred in men taking Viagra have involved patients with underlying anatomic or vascular risk factors," the company said. "This makes it impossible to determine whether these events are caused by the patient's underlying risk factors, anatomical defects, Viagra, or a combinations of these factors."
Eli Lilly spokeswoman Kindra Strupp said the company has updated its prescribing literature to reflect the reports of NAION. But "we don't see any cause-and-effect link," she added. "It certainly has not been established at this point."
Pomeranz said he disagreed with the drug companies' assertion that any association between the medications and eye damage was coincidental. In the 20 or so cases he reviewed, the onset of eye problems followed the patient's taking of Viagra -- usually by several hours, but sometimes by as few as 45 minutes.
"It's really the time connection between when the patient took the drug and when he noticed the loss of vision that convinces me there's a link," Pomeranz said.
His medical journal article conceded that "a definite causal relationship cannot be established at this time." But in view of the ever-growing use of such drugs, he wrote, the FDA must investigate.
"It is critical that irreversible ocular side effects such as NAION be ruled out in this class of drugs," he wrote.
The situation presents a common dilemma for the FDA: Although drugs may be tested on several thousand people before their approval, rare side effects may not emerge until many more have used the medication.
Some doctors said Friday that patients inquiring about the potential risk of eye damage were not overly alarmed.
"It's way out of proportion," said Dr. Steven Schwartz, chief of the retina division at the Jules Stein Eye Institute at UCLA. He sent three cases to the FDA, but as in the other reports received by the agency, the patients had other risk factors for NAION.
Side effects
Federal health officials are examining rare reports of blindness among some men using Viagra and Cialis. The warning labels of both impotence drugs, as well as Levitra, currently list the following side effects, according to the drugs' Web sites:
Viagra: "Less common side effects that may occur are temporary changes in color vision (such as trouble telling the difference between blue and green objects or having a blue color tinge to them), eyes being more sensitive to light or blurred vision."
Cialis: The drug "may uncommonly cause vision changes, such as seeing a blue tinge to objects or having difficulty telling the difference between the colors blue and green."
Levitra: The drug "may uncommonly cause vision changes, such as seeing a blue tinge to objects or having difficulty telling the difference between the colors blue and green."
The Food and Drug Administration is looking into 38 reports of eye damage in men who took Viagra, four involving Cialis, and one with Levitra. About 30 million men worldwide have taken the drugs.
"We haven't been able to determine that there is a cause and effect due to the medication," FDA spokeswoman Suzanne Trevino said. "But we are taking it seriously."
Most of the men who suffered eye damage did not go completely blind but lost part of their vision in one eye. Complicating the FDA's investigation, many of the patients had other risk factors, such as high blood pressure, that would make them vulnerable to the particular kind of eye problem.
The condition nonarteritic anterior ischemic optic neuropathy, or NAION involves damage to the optic nerve caused by an interruption of blood supply.
Trevino said the FDA is talking with Pfizer Inc., Viagra's manufacturer, about formally disclosing the risk in its prescribing literature for doctors. Eli Lilly & Co., which makes Cialis, recently changed its information to acknowledge reports of eye damage.
Dr. Howard Pomeranz, a professor of ophthalmology at the University of Minnesota, reported a suspected link between Viagra and eye damage in a medical journal article published in March.
"This particular eye problem should be added to the list of side effects that patients have access to," Pomeranz said Friday. But, he added, the medical evidence at this point would not warrant withdrawing the drug.
"I'm not recommending that men stop taking this drug," he said. "It's very good for what it's prescribed for."
However, Pomeranz said, patients who already have NAION in one eye should be strongly cautioned about the risk of using Viagra. And any patient who experiences blurriness or a loss of peripheral vision should stop taking such medications and consult a doctor immediately.
For patients who want to know whether they may be at risk, an eye exam may help answer the question. Doctors say one risk factor for NAION is tightly bundled nerves and blood vessels in the back of the eye. An eye doctor can identify that condition.
Medical factors that increase the risk of NAION include high blood pressure, high cholesterol and diabetes. Older people also are more likely to have the problem.
Dr. Michael Lee, a neuro-ophthalmologist at the Cleveland Clinic Foundation, treated a 67-year-old architect who had received a sample pack of Cialis from his primary care doctor.
One morning, two hours after taking the drug, the patient noticed a blurry patch in the bottom of his field of vision in his right eye, Lee said. His vision recovered by the next morning.
The patient took the drug three more times, with the same effect. Then he took another dose. That time, the blurry patch did not go away. The damage was permanent, Lee said.
The patient had two risk factors for NAION: high cholesterol and an especially small channel for blood vessels that run through the optic nerve behind the eye.
NAION strikes fewer than 10 people out of every 100,000 over age 50, Lee said.
In a statement, Pfizer said there was no evidence that NAION occurred more frequently in men taking Viagra than in men of similar age and health who did not take the drug.
"Most of the reported cases in which NAION has occurred in men taking Viagra have involved patients with underlying anatomic or vascular risk factors," the company said. "This makes it impossible to determine whether these events are caused by the patient's underlying risk factors, anatomical defects, Viagra, or a combinations of these factors."
Eli Lilly spokeswoman Kindra Strupp said the company has updated its prescribing literature to reflect the reports of NAION. But "we don't see any cause-and-effect link," she added. "It certainly has not been established at this point."
Pomeranz said he disagreed with the drug companies' assertion that any association between the medications and eye damage was coincidental. In the 20 or so cases he reviewed, the onset of eye problems followed the patient's taking of Viagra -- usually by several hours, but sometimes by as few as 45 minutes.
"It's really the time connection between when the patient took the drug and when he noticed the loss of vision that convinces me there's a link," Pomeranz said.
His medical journal article conceded that "a definite causal relationship cannot be established at this time." But in view of the ever-growing use of such drugs, he wrote, the FDA must investigate.
"It is critical that irreversible ocular side effects such as NAION be ruled out in this class of drugs," he wrote.
The situation presents a common dilemma for the FDA: Although drugs may be tested on several thousand people before their approval, rare side effects may not emerge until many more have used the medication.
Some doctors said Friday that patients inquiring about the potential risk of eye damage were not overly alarmed.
"It's way out of proportion," said Dr. Steven Schwartz, chief of the retina division at the Jules Stein Eye Institute at UCLA. He sent three cases to the FDA, but as in the other reports received by the agency, the patients had other risk factors for NAION.
Side effects
Federal health officials are examining rare reports of blindness among some men using Viagra and Cialis. The warning labels of both impotence drugs, as well as Levitra, currently list the following side effects, according to the drugs' Web sites:
Viagra: "Less common side effects that may occur are temporary changes in color vision (such as trouble telling the difference between blue and green objects or having a blue color tinge to them), eyes being more sensitive to light or blurred vision."
Cialis: The drug "may uncommonly cause vision changes, such as seeing a blue tinge to objects or having difficulty telling the difference between the colors blue and green."
Levitra: The drug "may uncommonly cause vision changes, such as seeing a blue tinge to objects or having difficulty telling the difference between the colors blue and green."
FDA Was Told of Viagra-Blindness Link Months Ago
More than 13 months before a scientific journal reported that Viagra had been linked to a rare form of blindness in some men, a Food and Drug Administration safety officer made the same observation from monitoring adverse event reports and told her supervisors that doctors and patients should be warned of the findings.
Her recommendation was well received, she told congressional investigators, but nothing happened. The FDA issued no public notice or proposed changes to the Viagra label. That came only following widespread publicity last month about the journal article and public concerns about the possible blindness-Viagra link.
The safety officer's experience was outlined in a letter last week to FDA Acting Commissioner Lester M. Crawford from Sen. Charles E. Grassley (R-Iowa), who said the agency had moved far too slowly on an emerging safety concern.
Criticism of the FDA's response to potentially harmful drug side effects has been frequent and sharp since Merck & Co. took its popular arthritis painkiller, Vioxx, off the market last fall after studies indicated that it increased the risk of heart attacks and strokes. The FDA has sought to tighten its drug safety oversight since then, but some critics say the agency is doing too little and still puts more emphasis on reviewing and approving new drugs than on safety concerns.
"I am troubled by the FDA's action, or lack thereof, relating to the updating of Viagra's product label," Grassley wrote. He said the agency's Office of New Drugs (OND) had done nothing "despite OND's knowledge of the blindness risks since January 2004 and general agreement among FDA staff last spring that the label should be updated."
Grassley also wrote that the safety officer, whose name was not disclosed, explained the agency's inaction by saying the Office of New Drugs "is under such time pressure to approve new drugs, often safety concerns needed to be 'fit in' where they could."
"What we appear to have here, Dr. Crawford, is yet another example of the 'separate but unequal' relationship" between the Office of New Drugs and the Office of Drug Safety, Grassley wrote.
Researchers remain uncertain whether Viagra and other impotence drugs pose a significant risk of blindness. Pfizer Inc., which makes the drug, says the side effect has not appeared in any of its 103 clinical trials of Viagra involving 13,000 patients and that the 23 million users have not reported an increased risk of blindness.
Late last month, however, after the possible link was reported in the Journal of Neuro-Ophthalmology, FDA spokeswoman Susan Cruzan said, "We take this seriously, and the FDA is working with the sponsors to make sure the public is aware of this so they can take it into consideration." The journal study examined seven cases where men suffered an unusual form of sudden blindness within 36 hours of taking Viagra.
On Monday, Pfizer said in a statement that it does not believe there is a causal relationship between Viagra and blindness but that it will add information about the possibility to its label. The company said the FDA had asked the makers of all impotence drugs to do the same.
"There is no evidence that Viagra causes blindness or any other serious ocular condition," said Joseph Feczko, Pfizer's chief medical officer. "Men taking Viagra are at no greater risk for blindness than men of similar age and health not taking the medicine."
In all, the FDA has said, 38 Viagra users and five users of other impotence drugs reported a sudden and permanent blindness in one eye called non-arteritic anterior ischemic optic neuropathy, or NAION. In a report Monday, CBS News said that the number is much higher, and that more than 800 patients and doctors have reported eye problems to the FDA after using Viagra over the past four years, with more than 140 cases of partial or total blindness. While these "adverse event" reports do not prove a causal link between the drugs and sudden blindness, drug safety experts look to them for trends and patterns.
This form of sudden blindness is caused by the blockage of blood flow to the optic nerve and is most common in older people, who disproportionately use Viagra. An estimated 1,000 to 6,000 Americans suffer an optic blockage each year.
Grassley's letter said the FDA safety officer first brought her concerns to the Office of New Drugs in January 2004. That was followed by a more formal draft safety "consult" in March 2004 and a final report the next month.
The letter paraphrases internal FDA documents as saying that Pfizer "resisted the FDA's initial request to update the Viagra label to include information about the NAION risks." Pfizer spokesman Mariann Caprino said the company does not comment on its interactions with the FDA. Earlier, another Pfizer spokesman said the company contacted the FDA about the blindness cases in March, after the journal report was published.
Grassley's letter also questions whether the FDA's adverse event reporting system would be capable of detecting NAION cases that might be associated with Viagra. Until now, it said, few doctors who prescribe Viagra would know to ask patients about vision problems, and few ophthalmologists who treat sudden blindness would know to ask about Viagra use. FDA officials said they had no comment on Grassley's letter.
All three impotence drugs on the market, Viagra, Cialis and Levitra, already warn users that the drug can cause minor vision changes that include blurring, sensitivity to light and the presence of a bluish hue. The makers of Cialis, Eli Lilly & Co. and Icos Corp., have voluntarily added a notice about the risk of sudden blindness to their label
Her recommendation was well received, she told congressional investigators, but nothing happened. The FDA issued no public notice or proposed changes to the Viagra label. That came only following widespread publicity last month about the journal article and public concerns about the possible blindness-Viagra link.
The safety officer's experience was outlined in a letter last week to FDA Acting Commissioner Lester M. Crawford from Sen. Charles E. Grassley (R-Iowa), who said the agency had moved far too slowly on an emerging safety concern.
Criticism of the FDA's response to potentially harmful drug side effects has been frequent and sharp since Merck & Co. took its popular arthritis painkiller, Vioxx, off the market last fall after studies indicated that it increased the risk of heart attacks and strokes. The FDA has sought to tighten its drug safety oversight since then, but some critics say the agency is doing too little and still puts more emphasis on reviewing and approving new drugs than on safety concerns.
"I am troubled by the FDA's action, or lack thereof, relating to the updating of Viagra's product label," Grassley wrote. He said the agency's Office of New Drugs (OND) had done nothing "despite OND's knowledge of the blindness risks since January 2004 and general agreement among FDA staff last spring that the label should be updated."
Grassley also wrote that the safety officer, whose name was not disclosed, explained the agency's inaction by saying the Office of New Drugs "is under such time pressure to approve new drugs, often safety concerns needed to be 'fit in' where they could."
"What we appear to have here, Dr. Crawford, is yet another example of the 'separate but unequal' relationship" between the Office of New Drugs and the Office of Drug Safety, Grassley wrote.
Researchers remain uncertain whether Viagra and other impotence drugs pose a significant risk of blindness. Pfizer Inc., which makes the drug, says the side effect has not appeared in any of its 103 clinical trials of Viagra involving 13,000 patients and that the 23 million users have not reported an increased risk of blindness.
Late last month, however, after the possible link was reported in the Journal of Neuro-Ophthalmology, FDA spokeswoman Susan Cruzan said, "We take this seriously, and the FDA is working with the sponsors to make sure the public is aware of this so they can take it into consideration." The journal study examined seven cases where men suffered an unusual form of sudden blindness within 36 hours of taking Viagra.
On Monday, Pfizer said in a statement that it does not believe there is a causal relationship between Viagra and blindness but that it will add information about the possibility to its label. The company said the FDA had asked the makers of all impotence drugs to do the same.
"There is no evidence that Viagra causes blindness or any other serious ocular condition," said Joseph Feczko, Pfizer's chief medical officer. "Men taking Viagra are at no greater risk for blindness than men of similar age and health not taking the medicine."
In all, the FDA has said, 38 Viagra users and five users of other impotence drugs reported a sudden and permanent blindness in one eye called non-arteritic anterior ischemic optic neuropathy, or NAION. In a report Monday, CBS News said that the number is much higher, and that more than 800 patients and doctors have reported eye problems to the FDA after using Viagra over the past four years, with more than 140 cases of partial or total blindness. While these "adverse event" reports do not prove a causal link between the drugs and sudden blindness, drug safety experts look to them for trends and patterns.
This form of sudden blindness is caused by the blockage of blood flow to the optic nerve and is most common in older people, who disproportionately use Viagra. An estimated 1,000 to 6,000 Americans suffer an optic blockage each year.
Grassley's letter said the FDA safety officer first brought her concerns to the Office of New Drugs in January 2004. That was followed by a more formal draft safety "consult" in March 2004 and a final report the next month.
The letter paraphrases internal FDA documents as saying that Pfizer "resisted the FDA's initial request to update the Viagra label to include information about the NAION risks." Pfizer spokesman Mariann Caprino said the company does not comment on its interactions with the FDA. Earlier, another Pfizer spokesman said the company contacted the FDA about the blindness cases in March, after the journal report was published.
Grassley's letter also questions whether the FDA's adverse event reporting system would be capable of detecting NAION cases that might be associated with Viagra. Until now, it said, few doctors who prescribe Viagra would know to ask patients about vision problems, and few ophthalmologists who treat sudden blindness would know to ask about Viagra use. FDA officials said they had no comment on Grassley's letter.
All three impotence drugs on the market, Viagra, Cialis and Levitra, already warn users that the drug can cause minor vision changes that include blurring, sensitivity to light and the presence of a bluish hue. The makers of Cialis, Eli Lilly & Co. and Icos Corp., have voluntarily added a notice about the risk of sudden blindness to their label
FDA Updates Labeling for Viagra, Cialis and Levitra for Rare Post-Marketing Reports of Eye Problems Possibly Associated with These Drugs
The Food and Drug Administration (FDA) has approved updated labeling for Cialis, Levitra and Viagra to reflect a small number of post-marketing reports of sudden vision loss, attributed to NAION (non arteritic ischemic optic neuropathy), a condition where blood flow is blocked to the optic nerve.
The FDA advises patients to stop taking these medicines, and call a doctor or healthcare provider right away if they experience sudden or decreased vision loss in one or both eyes.
Further, patients taking or considering taking these products should inform their health care professionals if they have ever had severe loss of vision, which might reflect a prior episode of NAION. Such patients are at an increased risk of developing NAION again.
The FDA states that: “At this time, it is not possible to determine whether these oral medicines for erectile dysfunction were the cause of the loss of eyesight or whether the problem is related to other factors such as high blood pressure or diabetes, or to a combination of these problems.” The manufactures contend their drugs are safe and not the cause of these problems.
The FDA advises patients to stop taking these medicines, and call a doctor or healthcare provider right away if they experience sudden or decreased vision loss in one or both eyes.
Further, patients taking or considering taking these products should inform their health care professionals if they have ever had severe loss of vision, which might reflect a prior episode of NAION. Such patients are at an increased risk of developing NAION again.
The FDA states that: “At this time, it is not possible to determine whether these oral medicines for erectile dysfunction were the cause of the loss of eyesight or whether the problem is related to other factors such as high blood pressure or diabetes, or to a combination of these problems.” The manufactures contend their drugs are safe and not the cause of these problems.
FDA Orders Warning Label on Viagra
The government on Friday ordered warnings onto the labels of Viagra and two other impotence drugs after some users developed a form of blindness. The Food and Drug Administration's move comes as the agency is under intense pressure to investigate more aggressively and warn the public about drug side effects.
At issue is sudden vision loss when blood flow to the optic nerve is blocked, a condition called NAION or non-arteritic anterior ischemic optic neuropathy.
NAION is considered one of the most common causes of sudden vision loss in older people, with anywhere from 1,000 to 6,000 cases a year. Moreover, risk factors include diabetes and heart disease, two of the leading causes of impotence.
The FDA has 43 reports of NAION among the impotence drug users: 38 for Viagra, four for Cialis and one for Levitra. They include varying degrees of vision loss, including blindness.
Those are rare numbers, given that Viagra alone has been used by 23 million men worldwide since its approval in 1998, according to maker Pfizer Inc.
"It is not possible to determine whether these oral medicines for erectile dysfunction were the cause," or whether other health conditions triggered NAION in the men, the FDA said in a statement Friday.
In addition to heart disease and diabetes, risk factors include being over age 50, high blood pressure, high cholesterol and smoking.
But FDA advised patients to stop taking the pills and call a doctor if they experience sudden or decreased vision loss in one or both eyes, and to tell their doctor if they have ever suffered an episode of sudden vision loss, because such patients are at increased risk of a second episode.
Cialis is marketed by Eli Lilly & Co. and ICOS Corp. Levitra is sold by GlaxoSmithKline PLC and Schering-Plough Corp. in the United States, and by Bayer AG elsewhere.
At issue is sudden vision loss when blood flow to the optic nerve is blocked, a condition called NAION or non-arteritic anterior ischemic optic neuropathy.
NAION is considered one of the most common causes of sudden vision loss in older people, with anywhere from 1,000 to 6,000 cases a year. Moreover, risk factors include diabetes and heart disease, two of the leading causes of impotence.
The FDA has 43 reports of NAION among the impotence drug users: 38 for Viagra, four for Cialis and one for Levitra. They include varying degrees of vision loss, including blindness.
Those are rare numbers, given that Viagra alone has been used by 23 million men worldwide since its approval in 1998, according to maker Pfizer Inc.
"It is not possible to determine whether these oral medicines for erectile dysfunction were the cause," or whether other health conditions triggered NAION in the men, the FDA said in a statement Friday.
In addition to heart disease and diabetes, risk factors include being over age 50, high blood pressure, high cholesterol and smoking.
But FDA advised patients to stop taking the pills and call a doctor if they experience sudden or decreased vision loss in one or both eyes, and to tell their doctor if they have ever suffered an episode of sudden vision loss, because such patients are at increased risk of a second episode.
Cialis is marketed by Eli Lilly & Co. and ICOS Corp. Levitra is sold by GlaxoSmithKline PLC and Schering-Plough Corp. in the United States, and by Bayer AG elsewhere.
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