Supplementary Material for: Immunogenicity and Safety of the Spikevax® (Moderna) mRNA SARS-CoV-2 Vaccine in Patients with Primary Humoral Immunodeficiency

Introduction: Reports on the immunogenicity and efficacy of the Spikevax® vaccine against SARS-CoV-2 in immunodeficient patients are still scarce. We aimed to evaluate the safety and immunogenicity of the vaccine in patients with primary humoral immunodeficiency. Methods: We enrolled 46 patients, including 34 patients with common variable immunodeficiency (CVID), 10 patients with unclassified hypogammaglobulinemia (HypoIg), and 2 patients with X-linked agammaglobulinemia. We collected the blood samples before vaccination (D 0), and 10 days (D +38) and 90 days (D +118) after the second vaccination. Further, we quantified SARS-CoV-2-specific T-cell response (QuantiFERON ELISA test), serum anti-RBD IgG, and anti-RBD IgA-specific antibodies (enzyme immunoassay). Results: We found that the vaccination elicited predominantly mild adverse events, comparable to healthy population. Vaccination response negatively correlated with a value of Immune Deficiency and Dysregulation Activity in all measured parameters. D +38, seroconversion for anti-RBD IgG and anti-RBD IgA was observed in 65% and 21% CVID patients, respectively. SARS-CoV-2-specific T-cell response was detected in less than 50% of CVID patients. Meanwhile, HypoIg patients had 100%, 90%, and 60% positivity rates for anti-RBD IgG, anti-RBD IgA, and T-cell response, respectively. Three months after the second vaccination, 82% of the responders remained positive for anti-RBD IgG, but only less than 50% remained positive for T-cell activity in CVIDs. Low immunogenicity was observed in patients with lung involvement and/or rituximab treatment history. No SARS-CoV-2 infection was reported within 6 months after the second vaccination. Conclusion: Spikevax® seems to be safe with satisfactory immunogenicity in patients with primary humoral immunodeficiency.