The House Committee on Energy and Commerce sent a letter Wednesday to acting US Food and Drug Administration (FDA) Commissioner Dr. Stephen Ostroff requesting more information on the safety of popular blood thinners Coumadin and its generic warfarin.
The letter cites a ProPublica report from earlier this summer that noted a high prevalence of adverse events tied to the use of these anticoagulants, particularly among nursing home residents. That report also notes that last year the Department of Health and Human Services (HHS) identified Coumadin and other anticoagulants as being frequently associated with adverse events.
Similarly, a report from 2012 from the Institute for Safe Medication Practices (ISMP) found that for the calendar year of 2011, the most frequently identified suspect drugs tied to serious, disabling, or fatal injury in direct reports to the FDA were the anticoagulants dabigatran (Pradaxa) and warfarin (Coumadin), "showing that inhibiting clotting ranks among the highest risk of all drug treatments.
"Warfarin (Coumadin) is the generic drug that since 1954 has been the mainstay of anticoagulation treatment," the ISMP report says. "Its disadvantages are that it requires regular laboratory tests to optimize dosing and interacts with numerous other drugs. It has placed near the top in the rankings of direct reports to the FDA for many years despite being a generic drug with a well-known safety profile. It accounted for 1,106 cases overall in 2011, including 72 deaths."
Another study conducted by FDA officials from 2007 noted that FDA added a so-called "black box" warning about warfarin's bleeding risk to the drug's label in 2006.
The representatives, however, said in the letter that the ProPublica report has prompted the committee "to consider whether there are any further actions FDA could take to decrease the incidence and severity of adverse events related to the use of Coumadin and/or warfarin."
The committee also seeks from FDA: