Anascorp (antivenom (centruroides scorpion)) Injection

Anascorp

Generic Name: Centruroides (Scorpion) Immune F(ab’)2 (Equine)
Date of Approval: August 3, 2011
Company: Rare Disease Therapeutics Inc.

Treatment for: Scorpion Stings

The U.S. Food and Drug Administration has approved Anascorp, the first specific treatment for a scorpion sting by Centruroides scorpions in the United States.

Venomous scorpions in the U.S. are mostly found in Arizona. Severe stings occur most frequently in infants and children, and can cause shortness of breath, fluid in the lungs, breathing problems, excess saliva, blurred vision, slurred speech, trouble swallowing, abnormal eye movements, muscle twitching, trouble walking, and other uncoordinated muscle movements. Untreated cases can be fatal.

Anascorp, Centruroides (Scorpion) Immune F(ab’)2 (Equine) Injection, is made from the plasma of horses immunized with scorpion venom. Anascorp may cause early or delayed allergic reactions in people sensitive to horse proteins. The manufacturing process for Anascorp includes steps to decrease the chance of allergic reactions and to reduce the risk of transmission of viruses that may be present in the plasma.

The effectiveness of Anascorp was based on results from a randomized, double-blind, placebo-controlled trial of 15 children with neurological signs of scorpion stings. These signs resolved within four hours of treatment in the eight subjects who received Anascorp, but in only one of the seven participants who received the placebo. The most common side effects were vomiting, fever, rash, nausea, itchiness, headache, runny nose, and muscle pain. In total, safety and efficacy data was collected from 1,534 patients in both open-label and blinded studies.

Highlights Of Prescribing Information

These highlights do not include all the information needed to use Anascorp safely and effectively. See full prescribing information for Anascorp.

Indications and Usage

Anascorp is an antivenom indicated for treatment of clinical signs of scorpion envenomation.

Dosage and Administration

Intravenous use only.

Initial dose	3 vials	• Reconstitute each vial with 5 milliliters of sterile normal saline. • Combine and further dilute to a total of 50 milliliters. • Infuse intravenously over 10 minutes.
Additional dose(s)	As needed	• Administer one vial at a time at 30-60 minute intervals. • Dilute to a total of 50 milliliters with sterile normal saline. • Infuse intravenously over 10 minutes.

• Initiate treatment with Anascorp as soon as possible after scorpion sting in patients who develop clinically important signs of scorpion envenomation, including but not limited to loss of muscle control, roving or abnormal eye movements, slurred speech, respiratory distress, excessive salivation, frothing at the mouth, vomiting.
• Close patient monitoring is necessary.

Dosage Forms and Strengths

Each vial contains a sterile, lyophilized preparation of not more than 120 milligrams total protein and not less than 150 LD50 (mouse) neutralizing units.

Contraindications

None.

Warnings and Precautions

• Severe hypersensitivity reactions, including anaphylaxis, are possible with Anascorp. Prepare for monitoring and management of allergic reactions, particularly in patients with a history of hypersensitivity to equine (horse) proteins or patients who have received previous therapy with antivenoms containing equine proteins.
• Delayed allergic reactions (serum sickness) may occur following treatment with Anascorp. Patient monitoring with a follow-up visit is recommended.
• Anascorp is made from equine plasma and may contain infectious agents, e.g. viruses.
• Localized reactions and generalized myalgias have been reported with the use of cresol as an injectable excipient.

Anascorp Side Effects

The most common adverse reactions observed in ≥ 2% of patients in the clinical studies for Anascorp were: vomiting, pyrexia, rash, nausea, and pruritus.

To report SUSPECTED ADVERSE REACTIONS, contact Rare Disease Therapeutics, Inc., at 1-877-851-1902, or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

Use In Specific Populations

Pregnancy: No human or animal data. Use only if clearly needed.

Patient Counseling Information

Advise patients to contact the physician or emergency department immediately if they experience any signs and symptoms of delayed allergic reactions or serum sickness up to 14 days following hospital discharge. Symptoms include rash, pruritus, joint pain, arthralgia, fever, lymphadenopathy, and malaise.