Bleeding Risk with Blood Thinner Cited
A cluster of bleeding episodes in patients treated with dabigatran (Pradaxa) led a group of New Zealand hematologists to express concern and call for better prescriber education.
A two-month review identified 78 bleeding episodes, including a dozen major bleeds, one of which might have contributed to a patient’s death, the hematologists wrote in a letter published in the March 1 issue of the New England Journal of Medicine.
Many of the bleeding incidents involved older patients and patients with impaired renal function. Prescriber error occurred in about a fourth of the complications, suggesting a lack of awareness of the potential risks associated with the drug.
“The serious consequences of the lack of an effective reversal agent should not be underestimated,” Paul Harper, MD, of Palmerston North Hospital in Palmerston North, New Zealand, and colleagues wrote. “Prolonged bleeding increased morbidity and possibly contributed to the death of one patient.
“Bleeding is an expected complication of dabigatran, especially in the elderly, a risk that is not completely mitigated by a dose reduction: 22 of our patients had a bleeding episode while receiving a reduced dose.”
According to the authors, hematologists expressed concern about a possible excess of bleeding incidents with dabigatran not long after the drug became available in New Zealand in July 2011. The concern led the Hematology Society of Australia and New Zealand to form a panel to investigate.
Generic Name: dabigatran (da BIG a tran)
Brand Names: Pradaxa
A two-month audit of medical records revealed 78 bleeding incidents, including 44 at the three hospitals where Harper and his co-authors work. The audit identified four factors associated with bleeding complications:
Pradaxa Bleeding Deaths Raise Concern
A report that the anticoagulant dabigatran (Pradaxa) has been linked to about 50 deaths from bleeding in atrial fibrillation patients has raised concern, but the drug’s manufacturer said the safety profile is where it should be.
“The clinical effectiveness and favorable safety profile of Pradaxa is positive and remains unchanged in light of recent reports about fatal cases of bleeding in the media,” Boehringer Ingelheim said in a statement.
Boehringer was responding to an article in the German publication Die Zeit, which reported the drug was associated with “deadly side effects.”
Reinhard Malin, PhD, a spokesperson for Boehringer was quoted in Die Zeit as confirming the association, and said that 50 deaths worldwide was probably in the right range.
“It’s difficult to give one figure as any death has to be validated and this is an ongoing process,” Malin told MedPage Today. “The number 50 seems reasonable, but I don’t have the exact figure.”
In its prepared statement, the company said, “Serious bleeding events can and do occur, with all anticoagulants including Pradaxa. Importantly, the bleeding events and fatal bleedings reported to date are considerably fewer than expected based on the trial data that support the use of Pradaxa in clinical practice,” citing two studies (N Engl J Med 2009; 361: 1139-1151 and N Engl J Med 2010; 363(19): 1875-1876).
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Published: November 02, 2011
Prescriber error (including failure to allow the international normalized ratio [INR] to fall below 2.0 before starting dabigatran, and use of the drug in patients with severe renal impairment)
Impaired renal function
Patient age
Lack of an effective reversal agent for dabigatran
WHAT IS PRADAXA?
PRADAXA is a prescription blood-thinning medicine used to reduce the risk of stroke and blood clots in people with atrial fibrillation not caused by a heart valve problem. With atrial fibrillation, part of the heart does not beat the way it should. This can cause blood clots to form, increasing your risk of a stroke. PRADAXA lowers the chance of blood clots forming in your body.
IMPORTANT SAFETY INFORMATION ABOUT PRADAXA
PRADAXA can cause bleeding which can be serious and sometimes lead to death. Don’t take PRADAXA if you currently have abnormal bleeding or if you have ever had an allergic reaction to it.
Your risk of bleeding with PRADAXA may be higher if you:
• are 75 years old or older
• have kidney problems
• have stomach or intestine bleeding that is recent or keeps coming back or you have a stomach ulcer
• take other medicines that increase your risk of bleeding, like aspirin products, non-steroidal anti-inflammatory drugs (NSAIDs) and blood thinners
• have kidney problems and take dronedarone (Multaq®) or ketoconazole tablets (Nizoral®)