Twinject

Twinject is the registered trademark of the first epinephrine autoinjector that contains two doses. It is used in medicine as an emergency treatment for severe allergic reaction (anaphylaxis).

History and development

"Twinject" was originally designed and manufactured by Verus Pharmaceuticals in the United States. The "Twinject" was developed after some studies showed that more than one dose of epinephrine may be required in up to 35 percent of anaphylaxis cases to properly address the allergic reaction. [ [http://twinject.ca/en/twinject.php Twinject Canada] ] It is currently available in two models "Twinject" 0.3 mg, and the "Twinject" 0.15 mg (see Dosing information below) in both the United States and Canada.

United States

"Twinject" was released in the United States on August 16, 2005. It was the first, and currently only, two dose epinephrine autoinjector approved for use in the United States by the FDA. In the U.S. autoinjectors are a regulated medical device and require a prescription from a medical doctor. [ [http://www.veruspharm.com/news_releases_08_16_2005.htm Verus Pharmaceuticals Announces U.S. Launch of Twinject for Anaphylaxis] ] The device is available in two strengths. In April 2007 Verus announced that changes were being made to the device, but the actual proposed modifications have not yet been made public.

Canada

On July 27, 2005, Verus announced that it had entered into an exclusive agreement with Paladin Labs to commercialize the "Twinject" in Canada. Paladin released the "Twinject" in Canada on September 22, 2005, after approval of Health Canada. [ [http://www.veruspharm.com/news_releases_09_22_2005.htm Verus Pharmaceuticals Announces Canadian Launch of Twinject for Anaphylaxis] ] In Canada the "Twinject" is not a regulated medical device, per se (it is kept behind the counter in pharmacies). While it does not require a prescription, many patients choose to have it prescribed as many insurance companies will only cover the cost of the device if it is prescribed. In Canada the "Twinject" usually retails between $95 CAD and $115 CAD [http://twinject.ca/en/faqs.php http://twinject.ca/en/faqs.php] ] On July 14, 2008, Health Canada issued an advisory [http://www.hc-sc.gc.ca/ahc-asc/media/advisories-avis/_2008/2008_109-eng.php] regarding the possibility of malfunctions with the the Twinject 0.3 milligram auto-injector and the Twinject 0.15 milligram auto-injector, and warning use of the device could pose a serious risk to users. Malfunctions that have been reported to the department included mechanical errors preventing the distribution of the first or second dose, a bent or cracked needle or an injector that did not deliver any of the drug at all. Since this device is used for critical life threatening allergic reactions, this is a major concern for those at risk. An alternative would be the EpiPen which is a well known established product with a track record of over 25 years of reliable operation.

The information below comes from the following web address-http://www.hc-sc.gc.ca/ahc-asc/media/advisories-avis/_2008/2008_109-eng.php for Health Canada the Canadian government responsible for oversight of medical products such as the Twinject.

Reported malfunctions with Twinject auto-injector pose potential health risks

Advisory2008-109July 11, 2008For immediate release

OTTAWA - Health Canada is advising Canadians of reported malfunctions with the Twinject 0.3 milligram (mg) auto-injector and the Twinject 0.15 mg auto-injector that may pose serious health risks to users.

Twinject is a pre-filled, single-use automatic injector containing an epinephrine solution that is used for the emergency treatment of severe allergic reactions, including anaphylaxis. The product is available in two dosing strengths, 0.3 mg and 0.15 mg. The injector is designed to administer one automatic injection, followed by a second dose by manual injection if necessary.

Since Twinject was first marketed in Canada on August 1, 2005, Health Canada has received 30 reports of malfunctions associated with the use of either the 0.3 mg or the 0.15 mg dosage strength. Most cases were reported to be life threatening and required either emergency room visitation or hospitalization. Twenty eight patients recovered without any major complications, and the outcome of the other two patients remains unknown.

The following are the three main types of malfunctions that were reported: 1. the needle did not fire with the first dose; 2. the plunger did not depress when attempting to administer the second dose; and 3. the needle was either bent or cracked.

In some cases, the auto-injector had a combination of malfunctions and did not deliver any drug.

Patients are advised to periodically review the operating instructions that accompany the product to ensure they remain informed of its proper use and care. Educational material, including training DVDs and demos, can be ordered free of charge from the manufacturer through the Next link will take you to another Web site website, or by phone at 1-877-894-6532. If patients are still concerned about the use of the Twinject auto-injector, they are encouraged to speak with their doctor or pharmacist.

Health Canada has been made aware that the manufacturer of Twinject made changes to the product in 2007, and released modified products to the Canadian market in November 2007 and in early 2008. The impact of the changes on the use of the product has not yet been established.

Health Canada will continue to assess this issue and will be working with the manufacturer to mitigate potential risks associated with this product. Health Canada is monitoring adverse reaction reports suspected of being associated with Twinject, and encourages Canadians to report adverse reactions to the Department through its Canada Vigilance Program.

Consumers requiring more information about this Advisory can contact Health Canada's public enquiries line at [phone], or toll free at 1-866-225-0709.

To report a suspected adverse reaction to this product, please contact the Canada Vigilance Program of Health Canada by one of the following methods:

Telephone: [phone]Facsimile: 1-866-678-6789

Canada Vigilance ProgramMarketed Health Products DirectorateOttawa, Ontario, AL 0701CK1A 0K9

E-mail: [e-mail]

The Canada Vigilance adverse reaction reporting form, including a version that can be completed and submitted online, is located in the MedEffect Canada area of the Health Canada Web site.

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Media Inquiries:Health Canada(613) 957-2983

Public Inquiries:(613) 957-29911-866 225-0709

Europe

On August 21, 2006, Verus announced that UCB, a European pharmaceutical company, will begin marketing and producing the "Twinject" for distribution in Europe. While the "Twinject" has yet to be sold outside Canada or the U.S., UCB has the option of commercialize the entire "Twinject" product line in all other territories beyond Europe (excluding the U.S. and Canada). [ [http://www.veruspharm.com/news_releases_08_21_2006.htm Verus Pharmaceuticals Announces Agreement with UCB for Commercialization of Twinject in Europe] ] Most markets in Europe require a prescription for epinephrine autoinjectors.

Dosage

The "Twinject" is available in two doses:
* In an anaphylactic emergency Adults weighing 30 kilograms/66 lb or more require a dosage of 0.3 mg of 1:1000 epinephrine. The "Twinject" 0.3 mg includes two adult doses.
* For children weighing 15 to 30 kilograms/33 to 66 lb, the standard dose is of 0.15 mg of 1:1000 epinephrine. The "Twinject" 0.15 mg contains two doses of 0.15 mg.
* For children weighing less than 15 kilograms/33 lb a dosage of 0.01 mg/kg of 1:1000 epinephrine is recommended. As the smallest dose available with the "Twinject" is 0.15 mg, for children weighing less than 15 kg other forms of injectable epinephrine may need to be considered. Package insert of Twinject 0.3mg ]

Usage

The "Twinject" is used to temporarily reverse the effects of a severe allergic reaction. Advanced medical care is required immediately after administering the epinephrine.

The "Twinject" contains a spring-loaded needle that shoots through a membrane in the tip and into the recipient's body to deliver the medication. A patient uses the device by removing the green locking cap from the bottom of the device, then the red cap at the top, forming a fist around the unit, and jabbing it firmly into a thigh until the click of the spring-loaded needle activating is heard. The patient holds the device in place for 10–15 seconds as the epinephrine is delivered. Using the device intravenously or subcutaneously is highly discouraged. After administering the device, patients are advised to seek immediate medical attention as epinephrine will temporarily relieve the symptoms of anaphylaxis but advanced medical care is required to permanently reverse the reaction. The second dose can be used after 10 minutes if the symptoms have not receded or if they begin to return before medical help has been reached.

To administer the second dose, the gray cap must be removed. Then, being careful with the exposed needle, the full syringe needs to be removed. Then a yellow (in the 0.3 mg dose autoinjector) or orange cap (in the 0.15 mg dose autoinjector) needs to be taken off the plunger. Then can the needle be inserted into the thigh and the plunger can be pushed completely down. It is advised that the second dose be prepared immediately following the first dose in order for it to be ready to administer when required.

Contraindications

There are no known contraindications to the use of epinephrine in a life-threatening allergic reaction.

torage

The "Twinject" usually has a shelf life of about 12 months or until the epinephrine (usually a clear liquid) begins to contain a precipitate, discolor (pinkish color, or more than only a slight yellow color. Once either of these occurs the "Twinject" should be immediately replaced. However, in the event of a life-threatening allergic reaction, even if the epinephrine has expired, the "Twinject" should be used.

The "Twinject" should be stored between 20 and 25 °C (68 to 77 °F). During excursions, epinephrine may be kept at a temperature of 15 to 30°C (59 to 86 °F). It should not be allowed to freeze and should not be refrigerated.

ee also

*Anaphylaxis
*Autoinjector
*Epinephrine
*EpiPen

External links

* [http://www.twinject.com/ US Twinject information]
* [http://www.twinject.ca/ Canadian Twinject information]
* [http://www.veruspharm.com/ Verus Pharmaceuticals]

References

http://www.hc-sc.gc.ca/ahc-asc/media/advisories-avis/_2008/2008_109-eng.php