Anticoagulants for prophylaxis and treatment of thromboembolic events

The Food and Drug Administration (FDA) wishes to correct misleading statements published recently inBlood.1-1 Dr David K. Cundiff asserts that several decision makers at FDA are “considering the withdrawal of the indication for anticoagulants (heparin, LMWH, and vitamin K antagonists) in prophylaxis and treatment of VTE.”^1(p723)Dr Cundiff's assertion is incorrect: FDA is not, and has not been, considering withdrawal of these indications for these drugs.

Rather, FDA merely evaluated materials submitted to the agency by Dr Cundiff, who questioned the value of heparin (and, by extension, of other anticoagulants) in the treatment of deep venous thrombosis and pulmonary embolism. Having reviewed these submitted materials, FDA notified Dr Cundiff in a letter dated December 19, 2001, that the agency was satisfied with the quality and quantity of data supporting heparin's indications.

In addition, Dr Cundiff states that heparin is a “grandfathered” drug,^1(p723) implying that its efficacy has never been reviewed by FDA. Dr Cundiff's statement is incorrect; heparin is not a grandfathered drug. FDA first approved heparin sodium injection on June 22, 1939, for prevention and treatment of postoperative thrombosis and embolism. A review of heparin's efficacy was conducted for FDA by the National Research Council of the National Academy of Sciences (NRC/NAS) under implementation of the drug efficacy study (DESI). In 1970, NRC/NAS concluded that heparin is effective for the treatment and prevention of all venous and arterial thrombosis, thromboembolic disease, and the prevention and treatment of pulmonary embolism. As has been explained to Dr Cundiff, FDA evaluated and concurred with the efficacy conclusions of the NRC/NAS report.1-2 In summary, FDA is satisfied with the quality and quantity of data available in support of heparin's stated indication.