Alternative strategies of posttransplant influenza vaccination in adult solid organ transplant recipients

Abstract

Solid organ transplant (SOT) recipients are at increased risk of influenza disease and associated complications. The mainstay of prevention is the annual standard‐dose influenza vaccine, as studies showed decreased influenza‐related morbidity and mortality in vaccinated SOT recipients compared to those unvaccinated. Nonetheless, the immune response in this high‐risk population is suboptimal compared to healthy individuals. Over the past two decades, several vaccination strategies have been investigated to overcome this inadequate immune response in SOT recipients. Howbeit, the best vaccination strategy and optimal timing of influenza vaccination remain unclear. This review will provide a detailed summary of studies of various influenza vaccination strategies in adult SOT recipients, discussing immunogenicity results, and addressing their limitations and knowledge gaps.

Poor humoral and T-cell response to two-dose SARS-CoV-2 messenger RNA vaccine BNT162b2 in cardiothoracic transplant recipients

“…Reduced immune responses to conventional vaccination concepts following organ transplantation [13,14] or in general, for patients under immunosuppressive therapy [17] have been reported before. However, the extent of missing humoral and cellular immune response following vaccination appears unexpected.…”

“…To gain adequate protection against other potentially threatening infections augmenting vaccination strategies such as higher doses per vial or additional boosting have been suggested for transplant recipients before [13,27,28]./ Considering the beneficial data on safety and adverse local and systemic events of the BNT162B2 vaccine in immunocompromised cancer [18] and transplant [29] patients, additional booster dose(s) could be considered, at least in those transplant patients showing at least some detectable B-or T-Cell-response to the first two doses. Of course, additional information on the effectiveness of other COVID-19 vaccines, e.g.…”

“…The immune response to other types of vaccines have been shown to be blunted in immunosuppressed patients [13,14].…”

Preparing for the 2020—2021 influenza season

“…[21][22][23] There is insufficient evidence to routinely recommend administering multiple influenza vaccine doses during a single influenza season or for administering high dose influenza vaccine to either SOT or HSCT recipients; however these continue to be studied. 24,25 However, the European Conference on Infections in Leukemia suggests that a second dose of influenza vaccine may be considered in individuals with graft versus host disease or lymphopenia or during an influenza outbreak if individuals are immunized less than six months after transplant. 19…”

COVID-19 Vaccination in Patients with Pre-Solid-Organ Transplantation

“…As of December 31, 2020, when focusing on kidney transplant recipients, there is no evidence of mRNA-vaccine-platform (BNT162b2 (Pfizer/BioNTech), mRNA-1273 (Moderna))induced off-target immune responses in large phase III clinical trials [11,12]. No replicative potential through homologous recombination demonstrated in AdV-vectored vaccine platform (AZD1222 (Oxford/AstraZeneca), JNJ78436735/Ad26.COV2.S (Janssen), Convidecia (Ad5-nCoV), Sputnik V (Gamaleya)), does not contain live virus in protein subunit vaccine platform (NVX-CoV2373 (Novavax), SARS-CoV-2 recombinant protein formulation (GSK/Sanofi) (Matrix-M1 contains the same QS21 saponin as the AS01 B adjuvant system contained in the recombinant varicella zoster vaccine) and no association between AS03 exposure and graft rejection (high incidence of anti-HLA antibodies in KTR vaccinated with AS03-adjuvanted influenza vaccines) in protein subunit vaccine platform and does not contain live virus and limited data available in peer-reviewed literature in whole-inactivated (killed) vaccine platform (EpiVacCorona (Vector Institute), BBIBP-CoV (Sinopharm), CoronaVac (SinoVac) [11][12][13][14][15][16] In conclusion, minimal risk to stable solid-organ-transplant recipients who are more likely to suffer a severe COVID-19 outcome than COVID-19 vaccine will be taken from COVID-19 vaccination.…”