Initial postmarketing experience with crotalidae polyvalent immune Fab for treatment of rattlesnake envenomation

Safety and Efficacy of Crotalidae Polyvalent Immune Fab in Pediatric Crotaline Envenomations

“…Other postmarketing studies have been performed since the approval of CroFab but included limited numbers of children. The most extensive pediatric studies to date were performed by Ruha et al 3 and Offerman et al 5 but only described a combined total of 15 pediatric patients younger than 13 years of age. The only other pediatric data available on CroFab use has been from a few case reports (one patient for each of three case reports), which are unique by nature and do not necessarily represent typical pediatric envenomations.…”

“…Control has been defined as arrest of local swelling and clear improvement (not necessarily normalization) in coagulation studies, platelet counts, and other systemic signs. 3 Laboratory studies are sent after each bolus, and hourly clinical assessments are performed as a means to guide repeat antivenom boluses. After achieving control, three maintenance doses consisting of two vials every six hours are administered for a total of six additional vials of antivenom.…”

“…Premarketing and postmarketing studies report CroFab is not only less immunogenic than wholeimmunoglobulin antivenoms but is also effective at halting the progression of local swelling and reversing systemic venom effects. [1][2][3] These studies have excluded children, and the safety and efficacy of CroFab in pediatric patients have been inferred from studies in adults. Our study was designed to evaluate the safety and efficacy of the use of CroFab in pediatric crotaline envenomations.…”

Successful Treatment of South American Rattlesnake (Crotalus durissus terrificus) Envenomation with Crotalidae Polyvalent Immune Fab (CroFab™)

“…Ovinederived Crotaline Polyvalent Immune Fab Antivenom (CroFab™), derived from the venoms of eastern diamondback rattlesnake (C. adamanteus), western diamondback rattlesnake (C. atrox), Mojave rattlesnake (Crotalus scutulatus), and cottonmouth (Agkistrodon piscivorus), has been approved in the USA since late 2000. In recent years, CroFab™ has largely replaced ACP due to decreasing supply of ACP and fewer acute and delayed hypersensitivity reactions associated with CroFab™ [2][3][4]. In this patient, ACP would have been the preferred treatment given its specificity for C. durissus terrificus; however, ACP is no longer available at our facility, the local zoo, or other local research facilities.…”

“…Although the hypofibrinogenemia was relatively mild, it lends support to our hypothesis that the antivenom provided some initial benefit by normalizing fibrinogen levels prior to discharge. Additional antivenom was not administered due to the minor nature of laboratory abnormalities and previously reported resistance to repeat dosing of CroFab™ for the treatment of recurrence [4].…”