Viagra to Warn on Vision Loss
Pfizer Inc., the world’s biggest drug maker, will change the label for its Viagra impotence pill to warn doctors about sudden vision loss that has occurred in some men who took the drug.
The Food and Drug Administration is asking all makers of impotence drugs to include similar warnings, New York-based Pfizer said in a statement Monday. No causal relationship has been made between Viagra and the condition, a type of eye stroke called non-arteritic anterior ischemic optic neuropathy, Pfizer said.
Pfizer released its statement before a CBS News report that examined four years of FDA data on complications among Viagra users. The analysis found 800 reports of eye problems, including 140 cases of partial or total blindness, CBS said. Pfizer said its own review found no evidence of increased risk of blindness in people taking Viagra.
The label change “doesn’t mean that Viagra poses a greater risk than it ever did,” said Jake Dollarhide, chief executive of Longbow Asset Management Co. in Tulsa, Okla., which manages about $25 million, including Pfizer shares. “It’s just that the FDA is more on the alert. Ultimately, it’s up to the FDA to figure out if there really is a link.”
Viagra, the first pill to treat erectile dysfunction, has been taken by 27 million men and generated $1.7 billion in sales last year. The FDA has received 43 reports of varying degrees of vision loss, including blindness, among users of impotence drugs: 38 among Viagra users, four among users of Cialis and one among users of Levitra, the agency said in May.
“As we’ve said before, this affects a small percentage of patients who are already at risk for the disease,” FDA spokeswoman Suzanne Trevino said Monday. “I don’t know that we’ll ever be able to say that [male impotence drugs are] the cause. It may be that patients taking these drugs are already at risk.”
A warning was added to Eli Lilly & Co. and Icos Corp.’s Cialis last month.
“There is no evidence that Viagra causes blindness or any other serious ocular condition,” said Joseph Feczko, Pfizer’s chief medical officer, in the statement released after the close of U.S. markets. “Men taking Viagra are at no greater risk for blindness ... than men of similar age and health not taking the medicine.”
Spokesman Daniel Watts declined to comment beyond the release.
Pfizer shares fell 44 cents to $28.08.
The optic nerve, which connects the brain and eye, is especially sensitive to shortages of blood. Illnesses such as diabetes and clogged arteries can hamper blood flow to the eye and increase the risk of damage to the nerve. Those conditions also are associated with impotence, Pfizer said in May.
