As part of their probe into direct-to-consumer advertising of prescription drugs, the two US Congressmen heading the investigation have written to the chief executives of four major drugmakers requesting improved accuracy and stronger guidelines in adverts.

John Dingell, chairman of the Committee on Energy and Commerce, and Bart Stupak, chairman of the Oversight and Investigations Subcommittee have sent letters to the CEOs of Pfizer, Schering-Plough, Merck & Co and Johnson & Johnson. In the letters they have asked them to commit to “business practices that would reduce misleading and deceptive DTC advertisements”.

The move comes just a fortnight after a Congressional hearing pointed a critical spotlight on three advertising campaigns that have been discontinued – Merck/S-P’s Vytorin (simvastatin/ezetimibe), Pfizer’s Lipitor (atorvastatin) and J&J’s Procrit (epoetin alfa).

Reps Dingell and Stupak said that during the hearing, representatives from the companies “failed to provide any assurances regarding future business practices, citing a lack of authority”. They invoked the guidelines laid down by the Pharmaceutical Research and Manufacturers of America on DTC advertising for their policy, a stance which has led to the Committee sending a letter to PhRMA president Billy Tauzin.

In that letter, they say “we are concerned that these guidelines as currently written may not prevent some of the misleading and deceptive marketing practices discussed during in our hearing”. Reps Dingell and Stupak ask PhRMA to update its guidelines so that all DTC ads specify all ‘black box’ warnings, among a number of other suggestions.

Rep Stupak concluded by saying that “consumers should not have to rely on the oversight function of Congress to make sure drug companies tell the truth in their ad campaigns”. He added that pharmaceutical firms “should consider it a privilege to air DTC ads and, as with all privileges, there comes responsibility. We intend to make certain that drug companies market their products properly in order to protect American consumers from manipulative commercials designed to mislead and deceive for profit.”