Improving Influenza Immunization Responses in Rheumatoid Arthritis: A Strategy To Enhance Protection Against A Preventable Cause Of Death In An At Risk Population?

Influenza, a vaccine-preventable respiratory disease, is ranked 8th among the causes of death in the Canadian population. Among rheumatoid arthritis (RA) patients, the incidence of both seasonal influenza and serious influenza-related illness (IRI) are increased. Despite being a high priority group targeted for vaccination, the diagnosis of RA and other patient-specific factors (i.e. older age, treatment, current smoking) are linked to impaired vaccination responses.

Thus the burden of influenza among people with RA is disproportionally high, and interventions to improve responses to influenza vaccination are urgently needed. Strategies to optimize protection in another vulnerable group, the elderly, include the use of quadrivalent vaccines, higher antigen doses, and adjuvants. A high-dose, trivalent, inactivated influenza vaccine (HD-TIV) has recently been shown to have a similar safety profile to standard dose vaccine (SD-TIV) with improved immunogenicity and protection in adults ≥65 years of age. Whether or not analogous strategies to improve responses to influenza vaccine will enhance protection in people with RA is unknown. The investigators hypothesize that the use of the HD-influenza vaccine will improve vaccine-induced protection (i.e. seroconversion and seroprotection) in people with RA compared to SD-influenza vaccine. The investigators propose to conduct a stratified, randomized, modified double blind, active-controlled trial to assess immune responses to two commercial influenza vaccines containing different antigen doses in individuals with RA.