Lab Tests Confirm Reduced Potency of New Heparin Formulation


April 08, 2010

April 8, 2010 (Rockville, Maryland) — Laboratory tests confirm that the new formulations of heparin are roughly 10% less potent than the heparin prepared using old standards [1].

The Food and Drug Administration (FDA) issued the safety communication today and is warning healthcare professionals that both the old and new formulations of heparin will be available for some time. As a result, physicians should consider clinical situations where the reduced potency might require dosage adjustments and more frequent monitoring, such as in patients requiring aggressive anticoagulation, including those undergoing cardiopulmonary bypass.

The current FDA-approved labeling for heparin remains unchanged, including the recommended doses.

The heparin reformulation is the result of manufacturing controls occurring in the wake of the 2007 and 2008 contamination that were linked to deaths and allergic reactions and was proposed by the US Pharmacopeia (USP), a nonprofit standards-setting organization. The agency first alerted physicians and the public about the change in the potency of heparin in October 2009, a health alert that was previously reported by heartwire . These most recent laboratory tests, requested by the FDA, confirm the reduced potency of the new heparin.

The FDA notes that the new heparin has been available since October 2009 and there will be supplies of both the old and new heparin stocked for use in hospitals and pharmacies for about three years.

There are four companies that market heparin in the US: APP, the largest manufacturer, Hospira, Baxter, and B Braun. Three of the four companies include the letter N on their product to identify the heparin with the new reference standard, while Hospira will identify the changed product with lot numbers that begin with the number "82" or higher.