Challenges and Controversies

This patient is at high-risk for acute hepatitis B infection given her history of injection drug use. She would benefit from being vaccinated while she is on buprenorphine-naloxone and hopefully not injecting drugs. If the 2-dose single-antigen hepatitis B vaccine (e.g. Heplisav-B) is readily available and if the patient is not pregnant, I would choose this option to provide her with immunity as soon as possible. Heplisav-B consists of 2 doses given at least 1 month apart. Ideally, this patient should also have her serum anti-HBs rechecked between 1-2 months from completing her final dose to ensure that she has developed an immune response (quantitative anti-HBs > 10 or qualitative "positive" or "reactive" anti-HBs result) to the hepatitis B vaccine. If she reports risk-behaviors since her last hepatitis B screening, I would consider reassessing her HBsAg and anti-HBc as well given the small chance of a new infection since her last assessment. In general, post-vaccination serologic testing should be performed for the following high-risk groups:
- Persons who inject drugs
- Persons with HIV or other immunocompromising conditions
- Hemodialysis patients
- Household and sexual contacts of HBsAg positive persons
- Health care personnel or public safety workers

If she is pregnant, she should be given the three dose single-antigen hepatitis B vaccine (e.g. Engerix-B or Recombivax-HB), which has the most robust pregnancy safety data. She does not need to wait until the 3rd trimester to receive her hepatitis B vaccine, it can be given in any trimester.

The newer three dose 3-antigen hepatitis B vaccine (e.g. PreHevbrio) is a great option for non-pregnant patients who may be less likely to respond to the single-antigen hepatitis B vaccine, or who did not yield a sufficient antibody response to another hepatitis B vaccine.

If the patient did not already have antibodies to hepatitis A, she could also have received the combination hepatitis A and B vaccine, given over 6 months.

I'm an addiction doctor, and I have patients similar to this woman. It's great that she has started taking buprenorphine, but substance use disorder (addiction) tends to be a relapsing condition. She is at risk of having her treatment be interrupted, something that is often accompanied by a chaotic lifestyle and logistical challenges. This can make adherence to a several-month immunization schedule -- the 3-shot series -- very problematic.

In the general population about one half of individuals don't get their third hepatitis B shot. The 2-dose series provides earlier antibody protection, and provides better protection in certain vulnerable populations. By the time she is done with "today's" appointment in the case scenario, a 2-dose vaccine series will mean she is already 50% immunized, and stands a good chance of being entirely done one month later.

Ultimately, the best vaccine to get is the one you have access to. The (usually) higher cost per dose of the 2-dose vaccine can be an issue, rendering it essentially unavailable for some patients. In that situation, a 3-dose vaccine should be started. A system of prompts/reminders should be in place to remind the patient and the immunizing entity of follow-up shots, which ideally could be administered by standing order, with minimal barriers (such as "must see a health care provider"). Consideration should be given to using "contingency management", such as having small rewards for those that complete the vaccine series.

Patients who are unable to return to the original immunizing entity should be advised that they may be able to get their 2nd (and 3rd) shots at a pharmacy or other convenient location, by just showing their immunization record. They should also be reminded that hepatitis B vaccine is an "anti-cancer" vaccine.