Senator Grassley's June 2005 Letter Criticizes FDA's Delay in Alerting Doctors and Patients

In January 2004 an FDA safety officer told her FDA supervisors that doctors and patients should be warned of a possible Viagra-blindness link that she had discerned from her review of adverse event reports concerning Viagra.

This internal FDA "alert" about Viagra came more than 13 months before the Journal of Neuro-Ophthalmology reported that Viagra had been linked to non-arteritic anterior ischemic optic neuropathy, or NAION, which can result in sudden and permanent blindness. The study which was the subject of this medical journal article examined seven cases where men suffered this relatively rare form of sudden blindness within 36 hours of them taking Viagra.

The January 2004 internal FDA alert about Viagra and blindness became known by means of a letter written last week by Senator Charles E. Grassley (R-Iowa) to FDA Acting Commissioner Lester M. Crawford.  Essentially, Senator Grassley's letter to the FDA criticized the agency for failing to act in a timely manner on the Viagra-blindness safety issue.

I am troubled by the FDA's action, or lack thereof, relating to the updating of Viagra's product label….  [The agency's Office of New Drugs (OND) did 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….  What we appear to have here, Dr. Crawford, is yet another example of the 'separate but unequal' relationship [between OND the Office of Drug Safety].

It is important to note that, to date, researchers have not been able to determine whether Viagra — as well as Cialis and Levitra, the other erectile dysfunction (ED) or impotence drugs — causes an increased risk of blindness. 

Pfizer Inc., the maker of Viagra, has stated that NAION, the optical side effect at issue, had not appeared in any of the 13,000 patients who participated in the drug company's 103 clinical trials of Viagra.  In late June 2005 Pfizer said there is no causal relationship between Viagra and NAION, or blindness.  At the same time, however, Pfizer said that it will add information to the Viagra package insert, or warning label, about the possibility of developing NAION after Viagra use.

The FDA said recently it is aware of 38 NAION reports from Viagra users and five NAION reports from users of other ED drugs. Subsequently, in a June 27, 2005 report, CBS News asserted that the number of NAION reports is considerably higher.  According to CBS News, over the past four years more than 800 reports of eye problems have been made to the FDA concerning patients using Viagra, with more than 140 cases of partial or total blindness.

(Posted by: Tom Lamb)