In Reply:—
Drs. Ho, Dion, and Karmakar suggest that hemostasis in the patients reported by Tobias, 1Svartholm et al. , 2and Slappendel et al. 3might have been achieved with administration of additional fresh frozen plasma. Ho et al. point out, as did I in the editorial 4that accompanied these reports, that recombinant activated coagulation factor VII (rFVIIa) has not been shown to be efficacious for states of dilutional coagulopathy. Parenthetically, it should be noted that when massive transfusion (one blood volume or more) is expected or achieved, use of whole blood rather than packed erythrocytes will provide the required coagulation factors and obviate or decrease the need for administration of plasma. 5The only currently approved use for rFVIIa is for patients who have hemophilia with inhibitors of coagulation factors VIII or IX. Part of the value of the case reports detailing “off-label” uses of rFVIIa is that the reports have provided a stimulus for the initiation of prospective, controlled, randomized, blinded studies examining the efficacy and safety of rFVIIa administered for bleeding secondary to causes other than hemophilia.
While there are sound theoretical rationales and laboratory data to suggest that rFVIIa might be efficacious for treating a variety of coagulation defects, demonstration of clinical efficacy awaits the results of these ongoing clinical trials. These trials should also produce data regarding the incidence (if any) of the possible theoretical adverse responses: vascular thrombosis and embolism, myocardial infarction, and coagulopathy resulting from intravascular coagulation. My previous comments continue to pertain:“diagnosis of the specific [hemostatic] defect and therapy with specific coagulation factors, plasma, or platelets remain the appropriate therapies…,”“it would not be appropriate, at this time, to attempt to replace standard diagnostic measures and standard accepted therapy with the use of rFVIIa,” and “when these measures truly fail, it may be reasonable to use rFVIIa as an attempted ‘rescue’ therapy.”4
After the completion of the studies in progress, we should have sufficient data on which to base decisions regarding the relative benefits and risks of the use of rFVIIa versus components derived from human blood for coagulopathies unrelated to hemophilia.