Crotalidae Polyvalent Immune Fab
Class: Antitoxins and Immune Globulins
ATC Class: J06AA03
VA Class: IM300
Brands: CroFab
Introduction
Antivenin (antivenom); ovine IgG Fab fragments capable of binding and neutralizing venom toxins of Crotalinae (pit vipers, crotalines; formerly known as Crotalidae or crotalids) native to North America.
Uses for Crotalidae Polyvalent Immune Fab
North American Crotaline Snakebite Envenomation
Treatment of envenomation following snakebites involving North American Crotalinae (pit vipers, Crotalinae, crotalines; formerly known as Crotalidae or crotalids). Designated an orphan drug by FDA for this use.
Crotalinae subfamily of venomous snakes includes rattlesnakes, copperheads, and cottonmouths or water moccasins.
May be effective in management of minimal, moderate, or severe envenomation involving Crotalus atrox (Western diamondback rattlesnake), C. adamanteus (Eastern diamondback rattlesnake), C. scutulatus (Mojave rattlesnake), Agkistrodon piscivorus (cottonmouth or water moccasin), and other North American crotalines.
Consultation with experts experienced in treating snakebites (e.g., regional certified poison control center at 800-222-1222) recommended to guide treatment decisions regarding individual patients.
Crotalidae Polyvalent Immune Fab Dosage and Administration
General
Initiate treatment as soon as possible after Crotalinae snakebite in patients with signs of progressive envenomation (e.g., worsening local injury, coagulation abnormality, other systemic signs of envenomation).
Has been effective in clinical studies when given within 6 hours of snakebite.
Monitor closely during and following administration.
Administration
IV Administration
Administer by IV infusion.
Reconstitution and Dilution
Must be reconstituted and diluted prior to administration.
Reconstitute appropriate number of vials of lyophilized Crotalidae polyvalent immune Fab (ovine) by adding 18 mL of 0.9% sodium chloride injection to each vial; mix by continuously manually inverting vial at a rate of 1 or 2 inversions per second until no solid material is visible in vial. Avoid foaming; do not shake. Reconstituted solution should be opalescent.
Combine contents of appropriate number of reconstituted vials and dilute total dose (total combined reconstituted vials) in 250 mL of 0.9% sodium chloride and gently swirl to mix. Because of concerns regarding fluid overload, consider lower volume of dilution fluid for children weighing <10 kg.
Use reconstituted and diluted solution within 4 hours after reconstitution. (See Stability.)
Rate of Administration
Administer by IV infusion over 60 minutes.
Start initial infusion using reduced rate of 25–50 mL/hour for first 10 minutes; observe patient closely for sensitivity or other reactions. If reduced rate well tolerated, give remaining initial infusion and subsequent infusions at rate of 250 mL/hour.
Dosage
Dosage expressed in terms of the number of vials.
Base initial dose (number of vials), need for additional initial doses to achieve envenomation control, and number of subsequent doses required to sustain envenomation control on individual patient response.
Age-related dosage adjustments not indicated.
