Breakthrough Infections Following mRNA SARS-CoV-2 Vaccination in Kidney Transplant Recipients

Abstract

Background. The clinical effectiveness of coronavirus disease 2019 (COVID-19) vaccination in kidney transplant (KT) recipients is lower than in the general population. Methods. From April to October 2021, 481 KT recipients with COVID-19, included in the Spanish Society of Nephrology COVID-19 Registry, were analyzed. Data regarding vaccination status and vaccine type were collected, and outcomes of unvaccinated or partially vaccinated patients (n = 130) were compared with fully vaccinated patients (n = 351). Results. Clinical picture was similar and survival analysis showed no differences between groups: 21.7% of fully vaccinated patients and 20.8% of unvaccinated or partially vaccinated died ( P = 0.776). In multivariable analysis, age and pneumonia were independent risk factors for death, whereas vaccination status was not related to mortality. These results remained similar when we excluded patients with partial vaccination, as well as when we analyzed exclusively hospitalized patients. Patients vaccinated with mRNA-1273 (n = 213) showed a significantly lower mortality than those who received the BNT162b2 vaccine (n = 121) (hazard ratio: 0.52; 95% confidence interval, 0.31-0.85; P = 0.010). Conclusions. COVID-19 severity in KT patients has remained high and has not improved despite receiving 2 doses of the mRNA vaccine. The mRNA-1273 vaccine shows higher clinical effectiveness than BNT162b2 in KT recipients with breakthrough infections. Confirmation of these data will require further research taking into account the new variants and the administration of successive vaccine doses.

Effectiveness of first, second, and third COVID-19 vaccine doses in solid organ transplant recipients: A population-based cohort study from Canada

“…Some research suggests vaccine effectiveness might be higher with mRNA‐1273 compared to BNT162b2. 35 , 36 Sixth, we may have missed some SARS‐CoV‐2 infections that were captured using rapid antigen tests. However, this number is likely low with widespread access to PCR testing during the study period, the administration of confirmatory PCR tests at Ontario transplant centers, and PCR testing upon admission to the hospital (regardless of the reason for admission).…”

“…Fifth, we did not have the power to present vaccine effectiveness estimates by vaccine type (e.g., BNT162b2 versus mRNA‐1273) or by solid organ transplant type (e.g., lung versus kidney). Some research suggests vaccine effectiveness might be higher with mRNA‐1273 compared to BNT162b2 35,36 . Sixth, we may have missed some SARS‐CoV‐2 infections that were captured using rapid antigen tests.…”

Predictors of Nonseroconversion to SARS-CoV-2 Vaccination in Kidney Transplant Recipients

“…Nonseroconversion rates after 2 vaccinations were relatively low compared with other studies using mRNA-based SARS-CoV-2 vaccines, which could be due to the cohorts consisting of long-term KTRs (median time after transplantation is 7.6 and 6.9 y) with 60% to 70% of them using MMF/MPA. Also, all fully vaccinated KTRs received the mRNA-1273 vaccine, which has higher seroconversion rates and clinical effectiveness than BNT162b2 in KTRs with breakthrough infections, 50 , 51 which aids in the discussion of whether mRNA-1273 should be the preferred vaccine in these patients. Although the type of third vaccine did not influence the prediction of nonseroconversion, we see an improved discrimination in the much smaller mRNA-1273 cohort, the type of vaccine on which the model was originally built.…”

Vaccination of solid organ transplant recipients previously infected with SARS-CoV2 induces potent responses that extend to variants, including Omicron

“…Immunosuppressed SOTRs have been reported to have poorer responses to Covid-19 vaccines than healthy populations, with one early study (before the advent of omicron variants) showing that SOTRs had an 82-fold higher risk of breakthrough infection and 485-fold higher risks of associated hospitalization and death compared to the general population 58,59 .…”