A Randomized Clinical Trial of 1-Dose vs Accelerated 2-Dose Schedule for Hepatitis A Virus (HAV) Revaccination Among People With Human Immunodeficiency Virus Who Were Nonresponders or Had Seroreversion After Primary HAV Vaccination

Background For people with human immunodeficiency virus (PWH) who have no serological responses to their primary hepatitis A virus (HAV) vaccination or have seroreversion after successful primary vaccination, the optimal revaccination strategy remains unclear. Methods In this open-label, randomized clinical trial, PWH who tested negative for anti-HAV antibodies after receiving a standard 2-dose series of primary HAV vaccination were enrolled and assigned in a 1:1 ratio to receive either 1 dose (the 1-dose group) or 2 doses of HAV vaccine administered 4 weeks apart (the 2-dose group). Serological response rates and anti-HAV antibody titers were compared at weeks 24 and 48. Results Of the 153 participants (77 in the 1-dose group and 76 in the 2-dose group), the overall serological response rates at week 48 after revaccination were similar between the 2 groups (2- vs 1-dose, 80.2% vs 71.4%, P = .20). However, anti-HAV antibody titers were consistently higher in the 2-dose group than in the 1-dose group. In subgroup analysis, PWH who were nonresponders to primary HAV vaccination were significantly more likely to mount a serological response after 2-dose HAV revaccination (68.4% vs 44.1%, P = .038). No severe adverse events were reported throughout the study. Conclusions Two-dose HAV revaccination administered 4 weeks apart yielded similar serological responses as 1-dose revaccination among PWH who were nonresponders or had seroreversion after primary HAV vaccination. The 2-dose revaccination schedule generated significantly higher anti-HAV antibody titers and was more likely to elicit serological responses at week 48 among PWH who were nonresponders to primary HAV vaccination. For people with human immunodeficiency virus who were nonresponders or seroreverters after primary hepatitis A virus (HAV) vaccination, an accelerated 2-dose revaccination (vs 1-dose) produced higher antibody titers and elicited a higher serological response rate at week 48 for nonresponders.