The world wide incidence of scorpion sting is not precisely known but is estimated to exceed 1.2 million stings annually. In the U.S. poison control centers report approximately 16,000 stings per year with the majority of these cases coming from the Southwest, Arizona in particular. The nature of volunteer reporting to poison control centers suggest these numbers greatly under estimate the actual incidence of stings. Not all scorpion stings are clinically significant; in fact most stings can be managed at home with basic first aid. It is only stings from the Centruroides sculpturatus, also known as the bark scorpion, which can result in dangerous systemic symptoms.

Symptoms
Patients stung by the bark scorpion (Centruroides sculpturatus) experience immediate burning and stinging sensation at the sting site. Following the pain, bark scorpion envenomation produces a pattern of neurotoxicity with a spectrum of severity ranging from the trivial to life threatening. Severe envenomation, more common in small children, may involve loss of muscle control, roving or abnormal eye movements, slurred speech, respiratory distress, excessive salivation, frothing at the mouth and vomiting.

Treatment¹
ANASCORP^® is the first ever FDA approved scorpion antivenom. Historically, when antivenom was not available, patients were admitted to hospital, often to the ICU and treated with high dose sedatives. ANASCORP^® is administered in the emergency or urgent care department. It is important to initiate treatment with ANASCORP^® as soon as possible after scorpion sting in patients who develop clinically important signs of scorpion envenomation.

Initial Dose¹
• The initial dose of ANASCORP^® is 3 vials.
• Reconstitute the contents of each vial with 5 milliliters of sterile normal saline (0.9% NaCl) and mix by continuous gentle swirling.
• Combine the contents of the reconstituted vials promptly and further dilute to a total volume of 50 milliliters with sterile normal saline (0.9% NaCl).
• Inspect the solution visually for particulate matter and discoloration prior to administration. Do not use if turbid.
• Infuse intravenously over 10 minutes.
• Monitor patient closely during and up to 60 minutes following the completion of infusion to determine if clinically important signs of envenomation have resolved.
• Discard partially used vials.

Additional Dosing¹
• Additional doses may be used if needed.
• Infuse one vial at a time at intervals of 30 to 60 minutes.
• Reconstitute the contents with 5 milliliters of sterile normal saline (0.9% NaCl) and mix by continuous gentle swirling.
• Further dilute to a total volume of 50 milliliters with sterile normal saline (0.9% NaCl). Inspect the solution visually for particulate matter or discoloration prior to administration.
• Infuse intravenously over 10 minutes.
• Monitor patient closely during and up to 60 minutes following the completion of infusion to determine if clinically important signs of envenomation have resolved.
• Discard partially used vials.

Reimbursement Information
Effective January 1, 2013, Centers for Medicare & Medicaid Services established a J-code in the HCPCS Level II standard national code set for ANASCORP^®: J0716 INJECTION, CENTRUROIDES IMMUNE F(ab’)_₂. UP TO 120 MILLIGRAMS. The entire HCPCS Annual Update is available and can be downloaded free of charge at: http://www.cms.hhs.gov/medhcpcsgeninfo

Regulatory Status
Since 1991, Rare Disease Therapeutics, Inc., has followed its mission to develop and deliver new therapies for orphan indications. This can be a long, complex and expensive process. Most discoveries never make it to the market. The cost of developing a new drug, according to the Tufts Center for the Study of Drug Development, averages $1.2 billion over 10 to 15 years.

The U.S. Food and Drug Administration (FDA) regulate the development of new drugs. Products designated as orphan drugs have to go through the same stringent regulatory process as other FDA regulated drugs and biologics. Both safety and efficacy are evaluated at each developmental stage.

Rare Disease Therapeutics, Inc. has established global working partners. We work collaboratively with our partners and these relationships have allowed for the development and manufacturing of new therapies.

Clinical Data¹
The efficacy of ANASCORP^® was assessed in a prospective double-blinded randomized placebo-controlled study, four open-label studies and one retrospective study in various treatment settings in the United States and Mexico, where scorpion envenomation is common. A total of 1534 patients ranging from less than one month to 90 years old were treated. The majority of patients (78%, 1204/1534) were pediatric, ranging from less than one month to 18.7 years of age. Male (52.3%) and female patients (47.7%) were equally represented. Treatment success was determined by resolution of clinically important signs of scorpion envenomation within four hours of starting infusion. The randomized placebo study enrolled 15 subjects, eight to the ANASCORP^® treated group and seven to the placebo. The symptom resolution success rate was 100% for the ANASCORP^® treated and 14.3% for the placebo group.

A retrospective hospital chart review provided historical data from envenomated patients (N=97) who did not receive antivenom but were treated with sedatives and supportive care for symptoms of envenomation. These data were used as a historical control for expected outcomes in the absence of antivenom treatment. The historical controls were pediatric patients admitted to two pediatric intensive care units between 1990 and 2003 for the treatment of scorpion envenomation with supportive care only. The proportion of patients that required intensive care support four hours after intensive care unit admission, and the overall duration of the intensive care support requirement were calculated.

Overall, 95-100% of patients were relieved of systemic signs associated with scorpion envenomation in less than four hours after initiating ANASCORP^® treatment. In the historical control database, only 3.1% of patients experienced relief of symptoms within 4 hours of hospital admission.

In 1396/1534 patients the mean time from start of ANASCORP^® infusion to resolution of clinical signs and symptoms of envenomation was 1.42 hours (0.2 to 20.5 hours). Pediatric patients generally experienced a slightly faster time to resolution (1.28 ± 0.8 hours) compared with that of adult patients (1.91 ±1.4 hours). The time to resolution of symptoms was not affected by use of sedatives (474 patients who received sedatives resolved in 1.49 ± 1.1 hours and 922 patients who did not receive sedatives resolved in 1.38 ± 0.9 hours).

Safety¹
Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice.