Immunogenicity and safety of a high-dose hepatitis B vaccine among patients receiving methadone maintenance treatment: A randomized, double-blinded, parallel-controlled trial

Background and aims: To explore whether the immunization with high-dose (60 mu g) hepatitis B vaccines in patients receiving methadone maintenance treatment (MMT) could yield a superior protection against hepatitis B infection than did the standard dose (20 mu g). Methods: We conducted a randomized, double-blinded, parallel-controlled trial in MMT patients. Patients with serologically negative hepatitis B surface antigen (HBsAg) and hepatitis B surface antibody (anti-HBs) were randomized in a ratio of 1:1 to receive three intramuscular injections of 20 mu g or 60 mu g recombinant hepatitis B vaccine at months 0, 1, and 6. Serum HBsAg and anti-HBs were measured at months 7 and 12 post-vaccination to assess the immunogenicity. Results: A total of 196 MMT patients were randomized and 195 received at least one injection (98 and 97 in 20 and 60 mu g vaccine groups, respectively). The 60 mu g vaccine group showed a seroconversion of antiHBs of 87.3%, high-level response rate of 56.3%, and GMC of 742.9 mIU/mL at month 7. While these results were numerically higher than the 20 mu g group, a statistical difference was not found. HIV infection and concomitant drug abuse were negatively associated with the robust immune responses. 7.7% of MMT patients receiving at least one dose of vaccine reported solicited adverse reactions within 7 days after vaccination, 2.6% reported unsolicited adverse reactions within 28 days after vaccination. None of the MMT patients reported serious adverse events or became HBsAg positive during the follow-up. Conclusions: The three-dose regimen of 60 mu g recombinant hepatitis B vaccine at months 0, 1, and 6 can yield a similar immunogenicity among MMT patients as compared to the 20 mu g vaccine. Conclusions: ClinicalTrials.gov identifier: NCT02991599 (C) 2017 Published by Elsevier Ltd.