Weak Immunogenicity of SARS-CoV-2 Vaccine in Patients with Hematologic Malignancies
Abstract
Abstract This study evaluated the safety and immunogenicity of BNT162b2 vaccine in patients with hematological malignancies. Antibodies blocking spike binding to immobilized ACE-2 (NAb) correlated with anti-Spike (S) IgG d42 titers (Spearman r\,=\,0.865, p \,<\,0.0001), and an anti-S IgG d42 level ≥q3100 UA/mL was predictive of NAb\,≥q\,30%, the positivity cutoff for NAb ( p \,<\,0.0001). Only 47% of the patients achieved an anti-S IgG d42 level ≥q3100 UA/mL after the two BNT162b2 inocula, compared to 87% of healthy controls. In multivariable analysis, male patients, use of B-cell targeting treatment within the last 12 months prior to vaccination, and CD19 + B-cell level <120/uL, were associated with a significantly decreased probability of achieving a protective anti-S IgG level after the second BNT162b2 inoculum. Finally, using the IFN-γ ELISPOT assay, we found a significant increase in T-cell response against the S protein, with 53% of patients having an anti-S IgG-positive ELISPOT after the second BNT162b2 inoculum. There was a correlation between the anti-S ELISPOT response and IgG d42 level (Spearman r\,=\,0.3026, p \,=\,0.012). These findings suggest that vaccination with two BNT162b2 inocula translates into a significant increase in humoral and cellular response in patients with hematological malignancies, but only around half of the patients can likely achieve effective immune protection against COVID-19.