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Merck: Drug Did Have Bleed Risk in Stroke Patients

From Associated Press (January 20, 2011)

WHITEHOUSE STATION, N.J. -- Merck & Co. confirmed late Wednesday that concern that its potential clot-preventing drug vorapaxar increased the risk of bleeding in stroke victims was in fact the catalyst that drove the company last week to unexpectedly halt a late-stage study of the drug.

Shares of Merck had plunged when the drugmaker said it halted a study of vorapaxar in stroke victims and would stop giving the drug -- seen as a possible blockbuster in its development pipeline -- to about 6,000 patients with a history of stroke that were enrolled in a separate study of over 26,000. At the time Merck said it was stopping the study in patients with acute coronary syndrome because that trial had reached a pre-determined number of endpoints, or medical issues like cardiovascular deaths, heart attacks and strokes.

Merck is studying vorapaxar for the prevention of cardiac events and had planned to submit the anti-clotting medication this year to the Food and Drug Administration for approval.

Merck officials had declined to elaborate in a conference call last week on whether there were bleeding concerns with the drug or why the trials were stopped and altered. The drug company said only that it made the decision based on recommendations from an independent Data and Safety Monitoring Board, or DSMB, that reviewed the trials.

On Wednesday, Merck said new information has been provided to investigators leading the ongoing study, including that the DSMB noted that the drug increased the risk of bleeding in some patients.

A lead investigator in one of the trials involving with stroke patients, Dr. Eugene Braunwald, has reported that "The DSMB has communicated to us that based on all of the data (safety and efficacy) available to them from both trials, they recommend that subjects with a history of stroke not receive vorapaxar. They have observed an increase in intracranial hemorrhage in patients with a history of stroke that is not outweighed by their considerations of potential benefit."

But Braunwald maintained that the DSMB recommended that the drug continue to be studied in patients without a history of stroke, clearing the way for Merck to continue assessing vorapaxar's benefit in more than 20,000 patients enrolled in the ongoing study.

".The DSMB recommended to us that it is important that the trial continue to completion in the more than 20,000 subjects who qualified for the trial with myocardial infarction or peripheral arterial disease who have not had a stroke," he stated.

In after-hours trading, Merck shares declined 9 cents to $33.83.


Posted: January 2011