Immunogenicity of COVID-19 Vaccinations in Hematological Patients: 6-Month Follow-Up and Evaluation of a 3rd Vaccination

• Main Authors: Aberle, J.H (Author), Blüml, S. (Author), Burgmann, H. (Author), Haslacher, H. (Author), Jaeger, U. (Author), Koblischke, M. (Author), Porpaczy, E. (Author), Schneider, L. (Author), Schubert, L. (Author), Tobudic, S. (Author), Winkler, F. (Author), Winkler, S. (Author)
• Format: Article
• Language: English
• Published: MDPI 2022
• Subjects: clinical trials; COVID-19; hematology–general; vaccine
• Online Access: View Fulltext in Publisher

 Here we analyzed SARS-CoV-2-specific antibodies and T-cell responses after two coronavirus disease 2019 vaccinations over a six-month period in patients with hematological malignancies and assessed the effect of a third vaccination in a subgroup. Sixty-six patients and 66 healthy controls were included. After two vaccinations seroconversion was seen in 52% and a T-cell-specific response in 59% of patients compared with 100% in controls (p = 0.001). Risk factors for a poor serological response were age (<65a), history of anti-CD20 therapy within the year preceding vaccination, CD19+ B-cells < 110/µL, and CD4+ T-cells > 310/µL. The magnitude of T-cell response was higher in patients <65a and with CD19+ B-cells < 110/µL. Patients and healthy controls demonstrated a significant decrease in SARS-CoV-2 S antibody levels over the period of six months (p < 0.001). A third vaccination demonstrated a strong serological response in patients who had responded to the previous doses (p < 0.001). The third vaccination yielded seroconversion in three out of 19 patients in those without serological response. We conclude that both humoral and cellular responses after SARS-CoV-2 immunization are impaired in patients with hematological malignancies. A third vaccination enhanced B-cell response in patients who previously responded to the second vaccination but may be of limited benefit in patients without prior seroconversion. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.