Calcitriol (1,25-dihydroxy-vitamin D3) coadministered with influenza vaccine does not enhance humoral immunity in human volunteers.

Calcitriol, also known as 1,25-dihydroxy-vitamin D3, is a steroid hormone that has been shown to have effects on cytokine production and lymphocyte proliferation. Coadministration of calcitriol with trivalent influenza vaccine in mice enhanced both mucosal and systemic antibody responses. We studied the effects of calcitriol coadministered with a commercially available influenza vaccine in 175 human volunteers in this double-blind, placebo controlled clinical trial. Subjects that received calcitriol experienced more pain at the injection site compared with placebo recipients. No significant differences in hemagglutination inhibition titers against H1N1, H3N2, or influenza B antigens were detected at 1 or 3 months postvaccination. We conclude that coadministration of 1.0 microg of calcitriol at a site adjacent to influenza vaccination does not enhance humoral immunity in human volunteers.

RCT Entities:   Population Interventions Outcomes