Assessment of the humoral response to the homologous Gam-COVID-Vac (Sputnik V) or heterologous Sputnik V/mRNA-1273 (Moderna) vaccination against SARS-CoV-2 in dialysis patients

Abstract

Background and Aim Dialysis patients are a high-risk population and have a reduced immune response to vaccination against SARS-CoV-2. The aim of this study was to assess the humoral response to homologous Gam-COVID-Vac (Sputnik V) and heterologous Sputnik V/mRNA-1273 (Moderna) vaccination in dialysis patients. The vaccination scheme depended on dose availability and the prioritization of risk populations as established by the Argentine Ministry of Health. Methods Previous COVID-19 infection was determined in symptomatic patients. Binding IgG antibodies against the spike (S) receptor-binding domain (RBD) of SARS-CoV-2 (anti-S-RBD) concentration was assessed between 3 and 16 weeks after the boost dose. Anti-S-RBD antibodies were quantified using the Abbott Diagnostics SARS-CoV-2 IgG II Quant chemiluminescent microparticle immunoassay (CMIA) on an Architect i2000 SR and an Alinity I analyzer (Abbott Diagnostics, Abbott Park, Illinois, USA). To standardize the results to WHO binding antibody units (BAU), a correction factor for Abbott arbitrary units (AU) was applied where 1 BAU/mL equals 0.142 AU, as previously established by Abbott with the WHO international standard NIBSC 20–136. Following the manufacturer’s recommendations, samples were considered reactive for anti-S-RBD when titers were above 50 AU/mL (7.2 BAU/mL). An 80% protective effect (PROT-80) against symptomatic SARS-CoV-2 infection was assumed when anti-S-RBD titers were 506 BAU/ml or higher. Charlson Comorbidity Index (CCI) score was classified as mild = 1–2, moderate = 3–4, and severe ≥ 5. Side effects were evaluated until day 7 by patients´ self-reported questionnaire. Results One hundred seven participants were enrolled [ n = 84 homologous (SpV/SpV), nn 23 heterologous (SpV/Mod)]. Median (IQR) age was 64 (50–75) years old and 79 (73.8%) were male. Additionally, 19 (22.6%) of the SpV/SpV and 4 (17.4%) of the SpV/Mod group had a prior confirmed SARS-CoV-2 infection ( p = 0.589). In the overall population, 103 patients reached seroconversion (96.3%). Anti-S-RBD IgG median titers (IQR) were higher in the heterologous [1222 (288–5680) BAU/mL] than in the homologous scheme [447 (100–1551) BAU/mL], p = 0.022. In a linear model adjusted for age, gender, days from first vaccination to boost dose and days from the boost dose to the anti-S-RBD IgG determination, previous SARS-COV-2 infection (B: 2062.2; CI95: 1231.8–2892.6; p < 0.001), and SpV/Mod vaccination scheme (B: 1294.6; CI95: 435.58–2147.6; p = 0.003) were independently associated with anti-S-RBD levels. Finally, a higher frequency of adverse effects was associated with the heterologous scheme, although they were well tolerated by all individuals. Conclusions The present study provides evidence that the homologous SpV/SpV and heterologous SpV/Mod schemes showed good e...

Humoral and T Cell Response to SARS‐CoV‐2 Vaccination in Patients With Rheumatoid Arthritis

“…Therefore, it is important to strongly encourage this group to receive additional and booster doses. Furthermore, comparable to what has been shown in the general population 35 and in dialysis patients from Argentina, 38 more than 90% and 80% of the patients receiving heterologous schemes developed a humoral and cellular response, respectively.…”

Neutralizing antibody levels detected early after mRNA-based vaccination do not predict by themselves subsequent breakthrough infections of SARS-CoV-2

“…Anti-RBD IgG antibodies were determined using the quantitative CLIA SARS-CoV-2 IgG II Quant Reagent Kit (Abbott), and the NAb antibodies were determined using the PETIA SARS-CoV-2 Neutralizing Antibodies Kit (SGM Italy; Rome, Italy). NAb antibodies were expressed as AU/ml, and anti-RBD IgG antibody levels were standardized into BAU/ml (1 BAU/ml = 0.142 x AU/ml), using the previously established conversion criteria (8)(9)(10).…”