Immunogenicity and safety of an adjuvanted hepatitis B vaccine in pre-hemodialysis and hemodialysis patients

Background. Due to their impaired immune system, patients with renal insufficiency have a suboptimal response to hepatitis B (HB) vaccination and frequent boosters are needed to maintain protection. GlaxoSmithKline Biologicals has developed a HB vaccine containing a new adjuvant system AS04 for use in this immunocompromised patient population. Methods. In an open, randomized clinical trial conducted in pre-hemodialysis (documented creatinine clearance <= 30 mL/min) and hemodialysis patients, over 15 years of age and naive for HB, the immunogenicity and safety of single doses of HB-AS04 (Fendrix (TM), GlaxoSmithKline Biologicals) were compared to double doses of commercially available HB vaccine (Engerix (TM), GlaxoSmithKline Biologicals) administered at 0, 1, 2, and 6 months, and followed-up for 36 months. Results. The HB-AS04 vaccine elicited a more rapid onset of protection than the currently licensed vaccine for this particular population, with 74% versus 52% of subjects seroprotected at month 3. After the vaccination course, seroprotection rates increased to 91% versus 84% in the HB-AS04 and standard vaccine groups, respectively. Differences persisted up to 36 months post-vaccination (73% vs. 52%, respectively). Antibody concentrations were higher following the HB-AS04 vaccine at all post-vaccination time points. During the follow-up, significantly fewer subjects primed with the HB-AS04 vaccine needed a booster dose as a consequence of anti-HBs loss below seroprotective levels (11/62 subjects in the HB-AS04 group vs. 22/57 subjects in the standard vaccine group, respectively, P= 0.014). The HB-AS04 was more locally reactogenic than the standard immunization regimen, with pain at the injection site occurring with 41% of HB-AS04 doses versus 19% of standard vaccine doses. The occurrence of grade 3 pain was less than 1% in both groups and all events resolved within the 4-day follow-up period. Conclusion. The improved immunogenicity profile and clinically acceptable reactogenicity of HB-AS04 vaccine are of key importance to provide a more rapid, enhanced, and longer seroprotection to these immunocompromised patients at risk for HB infection.