Plavix Hemophilia Warning Issued in UK

According to new warnings issued in Europe, potential side effects of Plavix have been linked to several cases of hemophilia, an autoimmune disease that can cause severe bleeding problems.  

Sanofi, the manufacturer of the blockbuster blood thinner, sent out a letter to healthcare providers in the United Kingdom on September 17, warning that there have been at least 12 cases of acquired hemophilia (spelled haemophilia in the U.K.) reported by patients who were placed on Plavix blood thinner treatment.

Reports of hemophilia from Plavix appeared anywhere from a few days to four months after the first dose of the blood thinner was used, according to the warning.

The individuals who acquired hemophilia include eight males, two females and two cases where the gender was not reported. All were between the ages of 65 and 81, with no previous history of blood problems. While two of the cases were considered life-threatening, none have resulted in a death, according to the letter.

The drug maker urges doctors in the U.K. to remain aware of the signs of hemophilia so that the condition can be promptly recognized to minimize the patient’s bleeding risk by referring the individual for treatment with a specialist and to discontinuing use of Plavix. It is unclear whether doctors in the U.S. are receiving a similar warning.

Plavix Health Concerns

Plavix (clopidrogrel) has been used by millions of people in the United States and is commonly prescribed to prevent blood platelets from sticking together and forming clots. There are between 2.5 million and 3 million Plavix prescriptions handed out each month in the U.S., and concerns have emerged in recent years that many of these may be unnecessary due to genetic resistance to Plavix.

While Plavix has been promoted as being better at its job than aspirin, with a cost that is many times higher than aspirin, questions have been raised about the effectiveness of Plavix for many patients and whether it actually provides any benefit over aspirin.

In August 2009, researchers from the University of Maryland identified a gene variant found in about one-third of the population that may signal a reduced effectiveness of Plavix. People with the CYP2C19 variant have reduced functioning of a liver enzyme that is supposed to convert Plavix from its inactive form to its active form, potentially making Plavix ineffective at reducing the risk of blood clots.

Unnecessary use of Plavix may expose individuals to an increased risk of gastrointestinal bleeding, severe ulcers, a rare blood disorder known as thrombotic thrombocytopenic pupura (TTP) and other injuries.

Bristol-Myers Squibb and Sanofi-Aventis currently face a number of Plavix lawsuits filed in state and federal courts throughout the United States, alleging that the drug makers have placed their desire for profits before the safety of consumers by aggressively marketing the medication while failing to adequately warn consumers or the medical community about the health risks associated with the medication.

Earlier this year, the U.S. Judicial Panel on Multidistrict Litigation (MDL) centralized all Plavix cases filed in the federal court system before U.S. District Judge Freda L. Wolfson in the District of New Jersey for coordinated pretrial proceedings.