Comparison of the immunogenicity of a monovalent influenza A/H1N1 2009 vaccine between healthy individuals, patients with chronic renal failure, and immunocompromised populations

Background Data on the immunogenicity (IG) of the influenza vaccine among patients at high risk of influenza-related complication are limited. Methods We studied the antibody titer following a single dose of monovalent 2009 influenza A (H1N1) vaccine between groups of adult patients who were healthy, those with chronic renal failure (CRF), kidney transplant (KT) recipients, and human immunodeficiency virus (HIV)-infected patients. The IG (primary endpoints) was accessed at 4 weeks after vaccination. The secondary endpoint was safety of the vaccine. Results A total of 293 patients were studied. Patients' mean age was 41(standard deviation [SD], 13.3) years old. At baseline, mean age (P <.001), history of vaccination in a prior year (P <.001), and geometric mean titers (GMT; P <.001) significantly differed between each groups and the majority (70%) of participants had the hemagglutination inhibition titer <1:10. The IG of the vaccine was highest in the healthy group (71.4 %). The response rate among CRF, KT, and HIV groups was 42.4% (risk ratios [RR], 0.72; 95% confidence interval [CI], 0.5-1.02), 31.9% (RR, 0.51; 95% CI, 0.34-0.76), and 29.7% (RR, 0.42; 95% CI, 0.3-0.6), respectively. The vaccine was well-tolerated in all studied groups. Thirty (10.2%) patients experienced at least 1 adverse reaction but systemic reaction was uncommon (3.4%). Conclusions A single dose of monovalent 2009 influenza A (H1N1) vaccine result in poor IG among high-risk populations, including CRF, KT and HIV patients.