The 131st Annual Meeting (November 15-19, 2003) of APHA

Abstract #72017

Paula J Lum, MD MPH¹, Judy Hahn, PhD², Kimberly Page Shafer, PhD¹, Jennifer Evans, MS², Peter J Davidson, BA², Ellen Stein, MPH³, Susan E. Fernyak, MD, MPH⁴, and Andrew R Moss, PhD². (1) Department of Medicine, Positive Health Program, University of California, San Francisco, UCSF Box 0874, San Francisco, CA 94143, 415-476-4082 x 411, plum@php.ucsf.edu, (2) University of California, San Francisco, Epidemiology & Biostatistics, San Francisco, CA 94105, (3) Epidemiology & Biostatistics, University of California, San Francisco, 74 New Montgomery St Suite 600, San Francisco, CA 94105, (4) Community Health Epidemiology and Disease Control, San Francisco Department of Public Health, 101 Grove Street, Room 204, San Francisco, CA 94102

Context: Most new or young injection drug users (IDU) in the U.S. are susceptible to hepatitis B virus (HBV) infection, a vaccine-preventable disease. However, completing the standard six-month schedule is often difficult for young IDU. Objectives: 1) To evaluate whether an accelerated HBV immunization schedule achieves better vaccine completion by young IDU than a standard schedule. 2) To examine whether an accelerated schedule provides an equivalent seroprotection rate as a standard schedule. Design & Setting: Randomized controlled trial among HBV-naive IDU under age 30 recruited by street outreach in San Francisco from January 2000-December 2001. Intervention: Participants were randomly assigned to receive three 20 mcg intramuscular recombinant HBV vaccine doses at 0-1-2 months (n=60), or 0-1-6 months (n=59). Main Outcome Measures: Vaccine series completion; seroprotection rate (SPR), defined as the proportion with anti-HBs > 10 mIU/mL measured four weeks after the third vaccine dose. Results: Seventy-three participants (61%) completed the protocol. In an intention-to-treat analysis, 43 participants (72%) in the accelerated arm and 30 participants (51%) in the standard arm completed their vaccine series (p=0.02). In the 56 participants, who completed their vaccines and returned for post-vaccination anti-HBs testing, 79% (27/34) in the accelerated arm and 91% (20/22) in the standard arm achieved serologic immunity (p=0.25). In an as-treated analysis, the SPR was 78% in the accelerated arm and 88% in the standard arm (p=0.34). Conclusion: Compared to the standard HBV immunization schedule, an accelerated schedule achieves better completion rates and evokes a comparable seroprotection rate in young, street-recruited IDU.

Learning Objectives:

At the conclusion of the session, the participant (learner) in this session will be able to:
• Compare HBV vaccine adherence achieved by accelerated vs. standard vaccine schedules among young IDU.
• Compare the seroprotection rates afforded by accelerated versus standard HBV vaccine schedules.
• Discuss the pros and cons of administering acclerated vs. standard HBV vaccine schedules to young IDU.

Keywords: Hepatitis B, Immunizations

Presenting author's disclosure statement:
I do not have any significant financial interest/arrangement or affiliation with any organization/institution whose products or services are being discussed in this session.