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medication-assisted treatment for substance use disorders

The SAMHSA Hepatitis A and B (TWINRIX) Vaccination Initiative

The Goal: The goal of this initiative is to enhance the capacity to prevent hepatitis infection through vaccination of at-risk individuals in substance abuse treatment.

Description: This initiative seeks the prevention of hepatitis B virus (HBV) and hepatitis A virus (HAV) infections by vaccination of individuals at risk because of substance abuse/dependency. The population covered will be persons receiving prevention or treatment services from a) SAMHSA’s regulated Opioid Treatment Programs, b) physicians approved to use buprenorphine, and c) SAMHSA current grantees under the Minority AIDS Initiative. This initiative augments SAMHSA’s current programs through the incorporation of disease prevention in HIV/HCV co-infected individuals by providing this vaccination against HAV and HBV infection. Approximately 60 sites around the United States and the District of Columbia are expected to participate and provide data to SAMHSA on the effectiveness of this approach. With this initiative, SAMHSA/CSAT will collaborate with the Division of Viral Hepatitis, Center for Disease Control and Prevention (CDC), to provide vaccine and educational materials against HAV and HBV infection in targeted minority populations in treatment for opioid addiction.

Background and Rationale for the Hepatitis A and B Vaccination Initiative

Hepatitis C infection and infection with the human immunodeficiency virus are frequent co-occurring infectious diseases in drug users and especially intravenous drug users. Co-occurring infections complicate the medical management of substance abuse treatment, particularly in the context of medication assistance treatment for opioid dependence. Controlling the epidemic of hepatitis infection in injection drug users requires the development and implementation of prevention, care and treatment strategies to reduce liver disease in persons who receive pharmacological therapies for opioid addiction. A specific strategy to prevent liver disease in these patients is to vaccinate eligible individuals against hepatitis A and hepatitis B infections.

Immunization is recommended for all susceptible persons 18 years of age and older who are, or will be, at risk of exposure to both hepatitis A and B viruses, including:

  1. Residents of drug and alcohol treatment centers
  2. Users of injectible illicit drugs
  3. Men who have sex with men
  4. Persons at increased risk of disease due to their sexual practices
  5. Patients with chronic liver disease, including alcoholic cirrhosis, chronic hepatitis C, autoimmune hepatitis and primary biliary cirrhosis would benefit from hepatitis A and B immunization
  6. Individuals who are at increased risk for HBV infection and who are close household contacts of patients with acute or relapsing hepatitis A and individuals who are at increased risk for HAV infection and who are close household contacts of individuals with acute or chronic hepatitis B infection, as well as
  7. Individuals at risk for progressive liver disease, including fulminant liver failure, on infection with hepatitis A and or hepatitis B. This includes individuals with HIV infection.

Twinrix® vaccine is the only FDA approved combination hepatitis A and hepatitis B vaccine, and is provided via a standard 3-dose regimen by intramuscular injection, given on a 0-, 1- and 6-month schedule. Twinrix® offers an opportunity to protect patients against both HAV and HBV with one combination vaccine. Twinrix® requires two fewer injections and has the potential for improved tolerability because of reduced number of injections. This may increase patient compliance, lead to time savings for you and your staff, and reduce administration costs for your practice or organization.

Twinrix® is generally well tolerated. Its safety profile was established in clinical trials involving the administration of 6,594 doses to 2,164 individuals and during routine clinical use of the vaccine outside the United States. The most common adverse events in clinical trials included soreness at the injection site, headache, and fatigue. They were mild and self-limiting, and did not last more than 48 hours. Adverse events seen with Twinrix® were similar to those observed after vaccination with monovalent vaccines. As with any vaccine, vaccination with Twinrix® may not protect 100 percent of recipients. Twinrix® is contraindicated in people with known hypersensitivity to yeast or any component of the vaccine in subjects having shown signs of hypersensitivity after previous administration of Twinrix® or monovalent hepatitis A or hepatitis B vaccines.

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