Transplant Trial Watch

Baseline serum interleukin-6 to interleukin-2 ratio is associated with the response to seasonal trivalent influenza vaccine in solid organ transplant recipients.

Fernandez-Ruiz M, Humar A, et al.

Vaccine 2015; 33(51): 7176-7182

To compare the safety and efficacy of high-dose intradermal (ID) influenza vaccination strategy, versus intramuscular (IM) trivalent influenza vaccine (TIV) in solid organ transplant recipients

Participants were randomized to receive either high-dose ID or standard dose IM seasonal TIV.

155 adult solid organ transplant recipients ≥ 3 months post transplant

The primary outcome measured was the seroconversion rate to at least one of the vaccine strains. Secondary outcomes measured were seroprotection rate and geometric mean seroconversion factor. Other measured outcomes were vaccine-associated adverse events, occurrence of microbiologically documented influenza infection, and biopsy-proven allograft rejection.

6 months

CET Conclusions
This paper reports a sub-analysis of a randomised controlled trial comparing two seasonal trivalent influenza vaccine preparations in solid organ transplant recipients. Influenza can cause significant morbidity and mortality in these patients, and vaccine response is lower than in non-immunosuppressed individuals. The authors aimed to investigate predictors of vaccine response by measuring cytokine levels pre—and post-vaccination. The ratio of IL-6 to IL-2 at baseline was highly predictive of a vaccine response, leading the authors to suggest a potential role in targeting novel vaccination strategies in at-risk patients. Whilst these findings are certainly interesting and worthy of further study, it should be noted that this is (presumably) a post-hoc retrospective analysis and would require validation in a prospective cohort of patients. None of the characteristics of a clinical test (e.g. sensitivity, specificity, predictive values) are reported so it is difficult to assess the utility of the ratio in a prospective cohort.

Jadad score

Data analysis
Available case analysis

Allocation concealment

Quality notes
Previously assessed as Baluch A, et al. Randomizedcontrolled trial of high-dose intradermal versus standard-dose intramus-cular influenza vaccine in organ transplant recipients. Am J Transplant 2013;13:1026–33.

Trial registration - NCT01180699

Funding source
Non-industry funded