Accelerated Hepatitis B Vaccination Schedule among Drug Users: A Randomized Controlled Trial

Background. Hepatitis B vaccine provides a model for improving uptake and completion of multidose vaccinations in the drug-using community. Methods. The Drugs, AIDS, STDs, and Hepatitis (DASH) project conducted a randomized controlled trial among not-in-treatment current drug users in 2 urban neighborhoods. Neighborhoods were cluster-randomized to receive a standard behavioral intervention (which provided information on human immunodeficiency virus [HIV]) or an enhanced behavioral intervention (designed to increase acceptance of or adherence to the hepatitis B vaccination protocol). Participants within clusters were randomized to a standard vaccination schedule (vaccines at 0, 1, and 6 months) or an accelerated vaccination schedule (vaccines at 0, 1, and 2 months). The outcomes were completion of the 3-dose vaccine and seroprotection against hepatitis B virus (HBV). Results. Of participants with negative screening results for HIV and HBV, 77% accepted hepatitis B vaccination, and 75% of vaccinees received all 3 doses. Injection drug users (IDUs) on the accelerated schedule were significantly more likely to receive 3 doses (76%) than those on the standard schedule (66%; P = .04), although for drug users as a whole the corresponding adherence rates were 77% and 73%, respectively. No difference in adherence was observed between the behavioral intervention groups. Predictors of adherence were older age, African American race, stable housing, and alcohol use. Cumulative HBV seroprotection (>= 10 mIU/mL) was gained within 12 months by 65% of those completing the schedule. Seroprotection at 6 months was greater for those on the accelerated schedule. Conclusion. The accelerated vaccination schedule improves hepatitis B vaccination adherence among IDUs.