COVID-19 Vaccine Efficacy in Haematopoietic Stem Cell Transplantation (HSCT) Recipients

Strategic Insights -

Researchers from Sheba Medical Center in Tel-Hashomer, Israel, conducted a study to examine the immunogenicity and safety of the Pfizer-BioNTech COVID-19 vaccine in HSCT recipients. The study involved 152 patients who were at least six months post-transplantation and without active acute graft-versus-host disease (GVHD). The team collected blood samples from the patients two to four weeks after the second vaccination and analyzed them for receptor-binding domain (RBD) antibodies and neutralizing antibodies (NA). The results showed that 77.6% of the patients developed RBD immunoglobulin G (IgG) with a geometric mean titre (GMT) of 2.61, compared to 98.9% of the control group with a GMT of 5.98.

Key Takeaways:

  • The Pfizer-BioNTech COVID-19 vaccine was found to be safe and effective in HSCT recipients, with 77.6% developing RBD IgG and 95.4% developing neutralizing antibodies.
  • The vaccine elicited a stronger immune response in immunosuppression-free patients, with those with less than six months post-transplantation showing lower GMTs.
  • The study suggests that HSCT recipients can benefit from COVID-19 vaccination, particularly those who are immunosuppression-free.
  • A significant fraction of patients developed protecting neutralizing antibodies, indicating that the vaccine can provide protection against COVID-19.
  • The study was conducted using a prospective cohort design, with 152 HSCT recipients and 272 immunocompetent healthcare workers as controls.

Statistics:

  • 77.6% of HSCT recipients developed RBD IgG after receiving the second vaccination.
  • The geometric mean titre (GMT) of RBD IgG antibodies in HSCT recipients was 2.61, compared to 5.98 in the control group.
  • 95.4% of HSCT recipients developed neutralizing antibodies after receiving the second vaccination.
  • The study involved 152 HSCT recipients, with a median of 28 days after the second vaccination.
  • The control group consisted of 272 immunocompetent healthcare workers.

Sources:

  • "Immunogenicity and Safety of the Bnt162b2 Mrna Covid-19 Vaccine In Haematopoietic Stem Cell Transplantation Recipients." British Journal of Haematology, 2021.
  • "Report Summarizes COVID-19 Study Findings from Sheba Medical Center (Immunogenicity and Safety of the Bnt162b2 Mrna Covid-19 Vaccine In Haematopoietic Stem Cell Transplantation Recipients)." Vaccine Weekly, December 8, 2021, p 653.