• Valdrina Ajeti Department of Pharmacy, Alma Mater Europaea Campus College Rezonanca, Pristina, Republic of Kosovo
  • Emin Melda Institute of Medical and Experimental Biochemistry, Faculty of Medicine, Ss. Cyril and Methodius University in Skopje, Republic of North Macedonia
  • Katerina Tosheska-Trajkovska Institute of Medical and Experimental Biochemistry, Faculty of Medicine, Ss. Cyril and Methodius University in Skopje, Republic of North Macedonia


SARS-CoV-2, S-RBD IgG, maglumi – 800, neutralizing antibodies, healthcare workers


Aim: The aim of our study was to compare the durability of BNT162b2 antibody response between male and female healthcare workers (HCWs), before vaccination and at 3, 9 and 12 months after administration of the second dose of the Pfizer/BioNTech BNT162b2 vaccine, using three antibody assays: Maglumi® SARS-CoV-2 Neutralizing Antibody (CLIA), Maglumi® SARS-CoV-2 S-RBD IgG (CLIA) and VIDAS® SARS-CoV-2 IgG (ELFA).

Material and methods: This study included 200 HCWs and the gender structure of the participants consisted of 41% males and 59% females. We utilized blood samples collected from HCWs who had not previously been infected with SARS-CoV-2. All procedures strictly followed the manufacturer's instructions.

Results:  Male and female HCWs had similar serum anti-S-RBD IgG concentrations before vaccination. Our findings showed the highest concentration of antibodies three months after vaccination in both genders, where females had non-significantly higher serum anti-S-RBD IgG antibodies with all three methods. Nine months after vaccination, females had significantly lower serum anti-S-RBD IgG measured with Maglumi Neutralizing Antibody (median 161 vs. 167 BAU/mL, p=0.017). However, at this time point, the difference between males and females was statistically insignificant regarding the serum values of anti-S-RBD IgG measured with Maglumi RBD (median 171.54 vs. 165.22 BAU/mL, p=0.38) and VIDAS RBD (68.16 vs. 103.3 BAU/mL, p=0.75). The level of anti-spike-RBD antibodies significantly decreased during 12 months after vaccination in males and females, (p<0.0001) determined by all three methods.

Conclusion: Our results demonstrated that there were no significant differences in SARS-CoV-2 IgG antibody concentrations between male and female HCWs.


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