Antibody Responses after a Third Dose of COVID-19 Vaccine in Kidney Transplant Recipients and Patients Treated for Chronic Lymphocytic Leukemia.

Julien Marlet,Hélène Longuet,Emmanuel Gyan,Sébastien Eymieux,Philippe Gatault,Karl Stefic,Zoha Maakaroun,Caroline Dartigeas,Catherine Gaudy-Graffin,Lynda Handala

doi:10.3390/vaccines9101055

Julien Marlet, Hélène Longuet + Show 8 more

Open Access

https://doi.org/10.3390/vaccines9101055

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Abstract

The impact of a third dose of COVID-19 vaccine on antibody responses is unclear in immunocompromised patients. The objective of this retrospective study was to characterize antibody responses induced by a third dose of mRNA COVID-19 vaccine in 160 kidney transplant recipients and 20 patients treated for chronic lymphocytic leukemia (CLL). Prevalence of anti-spike IgG ≥ 7.1 and ≥ 30 BAU/mL after the third dose were 47% (75/160) and 39% (63/160) in kidney transplant recipients, and 57% (29/51) and 50% (10/20) in patients treated for CLL. Longitudinal follow-up identified a moderate increase in SARS-CoV-2 anti-spike IgG levels after a third dose of vaccine in kidney transplant recipients (0.19 vs. 5.28 BAU/mL, p = 0.03) and in patients treated for CLL (0.63 vs. 10.7 BAU/mL, p = 0.0002). This increase in IgG levels had a limited impact on prevalence of anti-spike IgG ≥ 30 BAU/mL in kidney transplant recipients (17%, 2/12 vs. 33%, 4/12, p = 0.64) and in patients treated for CLL (5%, 1/20 vs. 45%, 9/20, p = 0.008). These results highlight the need for vaccination of the general population and the importance of non-medical preventive measures to protect immunocompromised patients.

Highlights

Vaccine effectiveness against symptomatic COVID-19 was estimated at between 70 and97% after two doses of COVID-19 vaccine in immunocompetent patients [1,2,3]
SARS-CoV-2 anti-spike IgG was tested for all patients at least 21 days after the second and/or third dose of mRNA COVID-19 vaccine, using a SARS-CoV-2 IgG II Quant assay on an Alinity i system (Abbott)
Prevalence of positive SARS-CoV-2 anti-spike IgG and anti-spike IgG ≥ 30 binding antibody units (BAU)/mL did not increase after the third dose (17%, 2/12 vs. 42%, 5/12, p = 0.37 and 17%, 2/12 vs. 33%, 4/12, p = 0.64)

Summary

Introduction

Vaccine effectiveness against symptomatic COVID-19 was estimated at between 70 and97% after two doses of COVID-19 vaccine in immunocompetent patients [1,2,3]. We defined responders as patients with positive SARS-CoV-2 IgG, corresponding to levels ≥ 7.1 binding antibody units (BAU)/mL, according to the manufacturer’s recommendations and previous studies [14,15,16,17,18]. Prevalence of positive SARS-CoV-2 anti-spike IgG (≥7.1 BAU/mL) in kidney transplant recipients tested either after the second (n = 97) or third dose (n = 160) of COVID-19 vaccine was not significantly different (43%, 42/97 vs 47%, 75/160, p = 0.61, Table 1).

Results

Conclusion