CROFAB- crotalus atrox immune fab antivenin (ovine), agkistrodon piscivorus immune fab antivenin (ovine), crotalus scutulatus immune fab antivenin (ovine) and crotalus adamanteus immune fab antivenin (ovine) injection, powder, lyophilized, for solution
BTG International Inc.
1 INDICATIONS AND USAGE
CROFAB is indicated for the management of adult and pediatric patients with North American crotalid envenomation (see Table 5 in Clinical Studies section (14) for definitions). The term crotalid is used to describe the Crotalinae subfamily (formerly known as Crotalidae) of venomous snakes which includes rattlesnakes, copperheads and cottonmouths/water moccasins.
2 DOSAGE AND ADMINISTRATION
For intravenous use only
2.1 Dosage
Administer CROFAB as soon as possible in patients who develop any signs of envenomation (e.g., local injury, coagulation abnormality, or systemic signs of envenomation) to prevent clinical deterioration. CROFAB was shown in clinical studies to be effective when given within 6 hours of snakebite.
Antivenin dosage requirements are contingent upon an individual patient�s response. Based on clinical experience with CROFAB, the recommended initial dose is 4 to 6 vials; however, the starting dose may vary from a minimum of 4 vials to a maximum of 12 vials based on clinical judgement and severity of envenomation [3].
The patient should be observed for up to 1 hour following the completion of this first dose to determine if initial control of the envenomation has been achieved. Initial control is achieved when local signs of envenomation are arrested (leading edge of local injury is not progressing), systemic symptoms are resolved and coagulation parameters have normalized or are trending toward normal. If initial control is not achieved by the first dose, an additional dose of 4 to 6 vials should be repeated until initial control of the envenomation syndrome has been achieved.
After initial control has been established, additional 2-vial doses of CROFAB every 6 hours for up to 18 hours (3 doses) is recommended. Optimal dosing following the 18-hour scheduled dose of CROFAB has not been determined. Additional 2-vial doses may be administered as deemed necessary by the treating physician, based on the patient�s clinical course.
Additional Patient Care (Supportive and Adjunctive Therapy): Infusion reactions, such as fever, low back pain, wheezing and nausea, may be related to the rate of infusion and can be controlled by decreasing the rate of administration of the solution [12]. Poison control centers are a helpful resource for individual treatment advice.
2.2 Preparation and Administration
Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit.
Each vial of CROFAB should be reconstituted with 18 mL of 0.9% Saline (diluent not included) and mixed by continuous manual inversion until no solid material is visible in the vial. Do not shake. The contents of all of the reconstituted vials should be further diluted to a total volume of 250 mL with 0.9% Sodium Chloride USP and mixed by gently swirling.
The initial dose of CROFAB diluted in 250 mL of saline should be infused intravenously over 60 minutes. However, the infusion should proceed slowly over the first 10 minutes at a 25- 50 mL/hour rate with careful observation for any allergic reaction. If no such reaction occurs, the infusion rate may be increased to the full 250 mL/hour rate until completion. Close patient monitoring is necessary.
The reconstituted and diluted product should be used within 4 hours.
3 DOSAGE FORMS AND STRENGTHS
CROFAB is supplied as a sterile, nonpyrogenic, purified, lyophilized powder. Each vial contains up to 1 gram of total protein, a maximum of 0.03 mg of mercury, and not less than the indicated number of mouse LD50 neutralizing units*: