UW HSIP- Subsequent HepB Initial Dose #3

2 min. readlast update: 10.22.2025

You have submitted two valid HepB vaccine doses. Your next step is to complete a third HepB vaccine dose to complete your initial HepB vaccine series and submit the record for approval.  

Make sure to follow the Hepatitis B vaccine dosing schedule for the vaccine type you are receiving if completing your initial Hepatitis B vaccine series:   

  • Heplisav-B (2-dose series): Dose #2 given 1 month after dose #1  

  • Engerix-B or Recombivax HB (3-dose series): Doses are given at respectively 0, 1, and 6 months (minimum dosing intervals are acceptable:  dose #1 to dose #2: 4 weeks / dose #2 to dose #3: 8 weeks / dose #1 to dose #3: 16 weeks)   

  • Hepatitis AB (Twinrix) (3-dose series): Doses are given at respectively 0, 1, and 6 months (minimum dosing interval of 5 months between dose #2 and dose #3)  

  • Accelerated Hepatitis AB (Twinrix) (4-dose series): Doses are given at respectively 0, 1 week, 21-30 days, and 12 months. However, students who choose this option should remember that 1 month after the last dose, you will still need to receive the titer to prove immunity.     

If you have submitted two HepB doses that were completed more than a year ago, then you do NOT need to restart the HepB vaccine series. When a HepB vaccine series is interrupted, you will need to continue from where you left off in the series. Please complete a HepB dose #3 as soon as possible and submit the record for approval.  

If you are continuing an interrupted HepB vaccine series and recently completed 3-dose HepB vaccine for your HepB dose #2, then complete the HepB dose #3 as directed: 

  • If you completed an Engerix-B or Recombivax HB HepB vaccine for your HepB dose #2, then you will need to complete a HepB dose #3 that is at least 2 months apart to complete your HepB vaccine series.  

  • If you completed a Hepatitis AB (TwinrixHepB vaccine for your HepB dose #2, then you will need to complete a HepB dose #3 that is at least 5 months apart to complete your HepB vaccine series.  

Once approved, a post-vaccination Subsequent HepB Titer tag will be created. You will need to complete a post-vaccination Quantitative HepB Surface Antibody Titer one month from the completed HepB vaccine series.   

If you have questions, please contact HSIP at myshots@uw.edu. 

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