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Differences in mRNA-1273 (Moderna) and BNT162b2 (Pfizer-BioNTech) SARS-CoV-2 vaccine immunogenicity among patients
Kevin Yau1, Christopher T Chan1, Kento T Abe1
1Division of Nephrology (Yau, Mullin, Shadowitz, Liu, Kostadinovic, Sukovic, Gonzalez, Oliver, Hladunewich) and Division of Infectious Diseases (Leis), Department of Medicine, Sunnybrook Health Sciences Centre, Temerty Faculty of Medicine, University of Toronto; Division of Nephrology (Yau, Chan, McGrath-Chong), Department of Medicine, Temerty Faculty of Medicine, University of Toronto; Department of Molecular Genetics (Abe, Gingras), University of Toronto; Lunenfeld-Tanenbaum Research Institute at Mount Sinai Hospital (Abe, Colwill, Gingras), Sinai Health System; Sunnybrook Research Institute (Jiang), Temerty Faculty of Medicine, University of Toronto; Public Health Ontario (Bolotin); Dalla Lana School of Public Health (Bolotin, Tran), University of Toronto; Department of Laboratory Medicine and Pathobiology (Tran), University of Toronto; Ontario Renal Network (Oliver, Blake, Hladunewich), Ontario Health; Li Ka Shing Knowledge Institute (Perl), Unity Health Toronto; Toronto, Ont.; BC Renal Agency (Atiquzzaman, Levin), Vancouver, BC; Division of Nephrology (Blake), Schulich School of Medicine & Dentistry, Western University, London, Ont.
Background:
Differences in immunogenicity between mRNA SARS-CoV-2 vaccines have not been well characterized in patients undergoing dialysis. We compared the serologic response in patients undergoing maintenance hemodialysis after vaccination against SARS-CoV-2 with BNT162b2 (Pfizer-BioNTech) and mRNA-1273 (Moderna).
Methods:
We conducted a prospective observational cohort study at 2 academic centres in Toronto, Canada, from Feb. 2, 2021, to July 20, 2021, which included 129 and 95 patients who received the BNT162b2 and mRNA-1273 SARS-CoV-2 vaccines, respectively. We measured SARS-CoV-2 immunoglobulin G antibodies to the spike protein (anti-spike), receptor binding domain (anti-RBD) and nucleocapsid protein (anti-NP) at 6-7 and 12 weeks after the second dose of vaccine and compared those levels with the median convalescent serum antibody levels from 211 controls who were previously infected with SARS-CoV-2.
Results:
At 6-7 weeks after 2-dose vaccination, we found that 51 of 70 patients (73%) who received BNT162b2 and 83 of 87 (95%) who received mRNA-1273 attained convalescent levels of anti-spike antibody (p < 0.001). In those who received BNT162b2, 35 of 70 (50%) reached the convalescent level for anti-RBD compared with 69 of 87 (79%) who received mRNA-1273 (p < 0.001). At 12 weeks after the second dose, anti-spike and anti-RBD levels were significantly lower in patients who received BNT162b2 than in those who received mRNA-1273. For anti-spike, 70 of 122 patients (57.4%) who received BNT162b2 maintained the convalescent level versus 68 of 71 (96%) of those who received mRNA-1273 (p < 0.001). For anti-RBD, 47 of 122 patients (38.5%) who received BNT162b2 maintained the anti-RBD convalescent level versus 45 of 71 (63%) of those who received mRNA-1273 (p = 0.002).
Interpretation:
In patients undergoing hemodialysis, mRNA-1273 elicited a stronger humoral response than BNT162b2. Given the rapid decline in immunogenicity at 12 weeks in patients who received BNT162b2, a third dose is recommended in patients undergoing dialysis as a primary series, similar to recommendations for other vulnerable populations.
