US regulators have sent a warning letter to Pfizer about a promotional video for Viagra which failed to point out the risks involved in taking the erectile dysfunction blockbuster.

The US Food and Drug Administration told Pfizer to discontinue the 30-second online video advertisement for Viagra (sildenafil), which appeared on CNN.com. It shows a group of musicians in Nashville belting out their version of Elvis Presley’s Viva Las Vegas, called Viva Viagra!

The ad says plenty about the benefits of taking Viagra but the agency said that it “raises public health and safety concerns through its complete omission of risk information for Viagra” by suggesting the drug “is safer than has been demonstrated". Among other things, Viagra’s label warns against use by men taking nitrates and notes the possibility of sudden vision and hearing loss, as well as priapism.

Pfizer has responded to the FDA’s letter saying that due to a technical error at CNN.com, “the safety information contained in a companion banner complementing the video was not displayed as instructed”. The company says that it discovered the error and notified the website “and our understanding was that the website corrected its error immediately”.

Pfizer added that to ensure such a mistake does not occur again, it has pulled all internet-based video ads featuring Viva Viagra! spots which require a companion banner with the appropriate risk information to simultaneously appear with the video.

The ad first made an appearance last summer just after the AIDS Healthcare Foundation had accused Pfizer of irresponsible direct-to-consumer drug advertising for Viagra. The company was accused of marketing to men who do not necessarily suffer from a clinical diagnosis of ED.

More positive heart disease data for Lipitor
On a brighter note, Pfizer has unveiled promising data from a five-year study which the firm claims is a further demonstration of the cardiovascular benefits of the cholesterol blockbuster Lipitor.

The results, from the Treating to New Targets (TNT) study, which have been published in the Journal of the American College of Cardiology, showed that Lipitor (atorvastatin) 80mg reduced the risk of heart attack and stroke by 32% in patients who have heart disease and chronic kidney disease, compared with patients taking the 10mg dose of the drug.

The study enrolled 10,001 people with coronary heart disease aged 35 to 75 in 14 countries and followed them for an average of five years. The safety of Lipitor 80mg in patients with chronic kidney disease was similar to that reported for the overall TNT population, with no unexpected safety concerns identified. Both doses of the drug were well tolerated.

James Shepherd of the University of Glasgow Medical School and a member of the TNT steering committee, said people with chronic kidney disease “are more likely to die from heart disease than to develop kidney failure”. It is therefore “critical for us to find new ways to reduce cardiovascular burden in these patients”, he added and “intensive statin therapy seems to be at least part of the solution”.

Sutent approved in Japan
The firm also noted that it has received marketing authorisation in Japan for Sutent (sunitinib malate), its treatment for kidney cancer. The multiple receptor tyrosine kinase inhibitor has been approved for gastrointestinal stromal tumour after failure of imatinib treatment due to resistance and for renal cell carcinoma not indicated for curative resection, plus metastatic RCC.