A+B+21 = A and/or B+180?
Hepatitis A and B Treatment

This past April at the 10th International Symposium on Viral Hepatitis and 
Liver Disease in Atlanta, researchers reported success in immunizing against 
hepatitis A and B with a combined vaccine on an accelerated 21-day schedule.
Dr. Jane N. Zuckerman from the Royal Free Hospital School of Medicine, in 
London, UK, and collaborators presented their findings after performing a multi-
center study. A total of 497 volunteers received a combined hepatitis A/B vaccine 
known as Twinrix(TM), given on a rapid 0,7- and 21-day schedule. They then 
measured the patients' immunoreactivity and compared them with a group who 
had received the hepatitis B vaccine Engerix(TM)-B on days zero, seven and 21 
and the hepatitis A vaccine Havrix(TM) on day zero. Researchers found that the 
rapid schedule yielded a strong immune response against hepatitis A and B and 
required fewer injections. Accelerating the administration schedule may prove to 
be useful in providing immunization support for travelers and others in need of 
more rapid support than current schedules. Zuckerman hopes that by year's end 
Twinrix (15 years old and above) and Twinrix Junior (1-15 years old) will be 
licensed for distribution in the US. It is currently available in Canada and Europe.

(TWINRIX™ is a combined vaccine for adults formulated from the same bulk 
vaccines that are used to produce HAVRIX™ (inactivated hepatitis A vaccine) 
and Engerix-B® (hepatitis B surface antigen, recombinant). Each 1.0 ml dose 
contains 720 ELISA units of inactivated hepatitis A viral antigen and 20 ug of 
hepatitis B purified surface antigen protein.
The recommended adult dose is 1.0 ml, injected intramuscularly, preferably in 
the deltoid region. Three primary doses are recommended, currently at intervals 
of 0, 1, and 6 months. The need for and timing of booster doses have not been 
established.
The most frequent adverse effect is mild injection-site soreness, reported after 
about 40% of doses. Other reported side effects include redness at injection site, 
headache, fatigue, malaise, and nausea. Side effects of the combined vaccines 
do not differ in frequency or severity from the monovalent vaccines).