Twinrix
Twinrix is a vaccine against hepatitis A and hepatitis B, manufactured by GlaxoSmithKline. Twinrix is administered over three doses.
The name was created because it is a mixture of two earlier vaccines - Havrix, an inactivated-virus Hepatitis A vaccine, and ENGERIX-B, a recombinant Hepatitis B vaccine.
Twinrix first entered the market in early 1997.
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[edit] Administration schedule
Twinrix can be administered on the same schedule as monovalent Hepatitis B vaccine: at 0- 1- and 6- months. In some circumstances, an accelerated dosing schedule of 0- 7- and 21-to 30- days followed by a booster at 12 months can be used and is believed to have similar efficacy as the traditional schedule.[1]
[edit] Efficacy
The CDC reports that clinical trials found the following levels of protection against Hep A and Hep B one month after each dose:[2]
- A: 93.8%, 98.8%, 99.9%
- B: 30.8%, 78.2%, 98.5%
GlaxoSmithKline claims that its studies found 70% of subjects had antibodies against hepatitis B a month after just the first dose, however.[3]
[edit] Autoimmune concerns
Although Twinrix has enjoyed much success and has provided benefit for millions, there is one report concerning a putative exacerbation of autoimmune hepatitis possibly due to innoculation by Twinrix.[4]. It must be noted, however, that since the vaccination for Hepatitis A is a killed vaccine, and Hepatitis B is a recombinant vaccine, that there is no possibility for the vaccination to mutate and cause Hepatitis A or B in an immunized individual.
[edit] Advertising
In order to promote this new vaccine, GlaxoSmithKline launched a TV ad advertising, dramatizing that in Caribbean destinations like the Dominican Republic, a person can get Hepatitis A and/or Hepatitis B from an otherwise calm beach setting, from the sand soil up to the swimming water.[5]
TWINRIX, HAVRIX and ENGERIX-B are registered trademarks of GlaxoSmithKline; if the same vaccine is available from others, it will have another name.
[edit] See also
[edit] References
- ^ http://us.gsk.com/products/assets/us_twinrix.pdf
- ^ Notice to Readers: FDA Approval for a Combined Hepatitis A and B Vaccine
- ^ Twinrix Adult Vaccine, SPC from the eMC
- ^ Csepregi A, Treiber G, Röcken C, Malfertheiner P (July 2005). "Acute exacerbation of autoimmune hepatitis induced by Twinrix". World journal of gastroenterology : WJG 11 (26): 4114–6. PMID 15996042. http://www.wjgnet.com/1007-9327/11/4114.asp.
- ^ Twinrix TV commercial VIDEO (hosted on YouTube)
