In the latest development, the House Committee on Energy and Commerce has demanded a host of documents from the chief executives of both drugmakers, as well as the Food and Drug Administration and the Webmaster for a Web site called Cafepharma Inc.
On the site, anonymous postings by pharmaceutical sales representatives indicate some reps knew about the study's results by March 2007.
"These Web site entries are obviously troubling and raise further questions as to whether anyone within Merck or Schering-Plough knew the results of the ENHANCE trial prior to the official release of data," committee letters to the officials state.
The Vytorin study, called ENHANCE, was completed in April 2006, but the companies didn't release partial results until Jan. 14, 2008, five weeks after the committee began investigating the delay.
Vytorin combines Schering-Plough's Zetia with Merck's older cholesterol drug Zocor, a former blockbuster available since June 2006 as a generic for about one-third Vytorin's cost. The study found Vytorin was no more effective than the generic at limiting plaque buildup in neck arteries, but did lower cholesterol a bit more.
The companies have said the complexity of the study, which the companies paid for, and difficulty reading ultrasound images of participants' arteries delayed the results.
The two New Jersey companies have a joint venture that markets Vytorin and Zetia, which together brought in $5.1 billion in sales in 2007, up from $3.8 billion in 2006.
"We will cooperate with the committee," Merck spokesman Chris Garland said Tuesday. "We stand by the safety and efficacy profiles of both Zetia and Vytorin."
He said Merck officials first saw study results starting in late December.
The House committee's letters state the committee is "investigating the withholding of clinical trial data" and cite entries from the Cafepharma Web site.
One posting cited, from March 13, 2007, states: "have a buddy at (Schering-Plough Research Institute). He says that the study is a bust. Adding Zetia to already maxed-out statin is useless," a reference to the maximum dose of Zocor used in the study.
A June 3, 2007, posting says of the study: "Heard it crashed and burned!"
The committee's letters give the companies two weeks to turn over information, including when company officials became aware of the Internet postings and what they have done to investigate the source, and order them not to destroy or tamper with any records.
The Web site officials were ordered to identify the people who made the postings. The Webmaster, Sarah Palmer, said in an e-mail late Tuesday that the site does not collect user information with anonymous posts on its message boards and so she did not believe it had any user information to give the committee.
The four letters include ones to FDA chief Dr. Andrew C. von Eschenbach, demanding all records about the study's initial design and changes after it began, and a second letter to the drugmakers' CEOs demanding more information because of questions raised by their prior response to committee inquiries. Messages left with the FDA were not returned.
The letters, dated Feb. 11, were signed by the committee chairman, Rep. John D. Dingell, and Rep. Bart Stupak, chairman of the Subcommittee on Oversight and Investigations.
The committee also is investigating related issues, including the sale of "significant numbers of shares of Schering-Plough" stock by one of its top executives, Carrie S. Cox, president of global pharmaceuticals, after the study ended. Securities and Exchange Commission filings show Cox sold $29.7 million worth of stock then - mostly on April 20, 2007, and May 1, 2007 - with some sales coming after she received free stock grants or exercised options to buy shares cheaply.
"If there's evidence of criminal wrongdoing, we would turn it over" to the authorities, likely the Justice Department or the SEC, said committee spokeswoman Jodi Seth.
The committee also is looking at how much federal health programs spent on Vytorin and at the content of consumer advertising, including the once-ubiquitous "Food and Family" ads that touted Vytorin as reducing cholesterol both from the food people eat and what their body produces due to their genes. TV ads for both Vytorin and Zetia have been halted temporarily.
"These companies should know that this investigation is far from over," Dingell said in a statement.
Schering-Plough CEO Fred Hassan, speaking to analysts after his company released its quarterly earnings report Tuesday, said the company stands behind the drugs and that patients have been exposed to misleading information from a small study.
One analyst, Brian Orelli of investment advisers The Motley Fool, said the widening congressional probe would "create more media drama, which is going to cause the companies to look bad."
In trading Tuesday, Schering-Plough shares rose $1.21, or 5.9 percent, to $21.83, and Merck shares rose $1.24, or 2.7 percent, to $46.53. Both were still near their 52-week lows.
