Impact of squalene-based adjuvanted influenza vaccination on graft outcome in kidney transplant recipients.

Background: Safety concerns have been raised about the use of adjuvanted vaccines after kidney transplantation.

Methods: We retrospectively analyzed 65 kidney transplant (KT) recipients who received ≥1 dose of influenza vaccine (pandemic or seasonal) during the 2009-2010 campaign. Participants were classified into 2 groups: those who received a squalene-based AS03- or MF59-adjuvanted vaccine ("adjuvanted vaccination" [AV] group, n = 37) and those who exclusively received non-adjuvanted vaccines ("non-adjuvanted vaccination" [NAV] group, n = 28). Primary outcomes included occurrence of biopsy-proven acute graft rejection (BPAR) and graft function at months 6 and 12 after vaccination. Patients were followed up until graft loss, death, or October 2010.

Results: Four episodes of BPAR occurred during post-vaccination follow-up, with no differences between the AV and NAV groups, in terms of cumulative incidence (5.4% vs. 7.1%, respectively; P = 0.581), incidence rate (0.22 vs. 0.18 episodes per 1000 transplant-days; P = 0.950), or occurrence of severe episodes (T-cell-mediated BPAR of grade ≥2a) (2.7% vs. 3.6%; P = 0.680). No between-group differences were seen in graft function after vaccination.

Conclusion: Adjuvanted influenza vaccination in KT recipients seems to be safe regarding graft outcome.