Safety and Immunogenicity of the BNT162b2 mRNA COVID-19 Vaccine in Patients after Allogeneic HCT or CD19-based CART therapy—A Single-Center Prospective Cohort Study

• Published in: Transplantation and cellular therapy Vol. 27; no. 9; pp. 788 - 794
• Main Authors: Ram, Ron, Hagin, David, Kikozashvilli, Nino, Freund, Tal, Amit, Odelia, Bar-On, Yael, Beyar-Katz, Ofrat, Shefer, Gabi, Moshiashvili, Miguel Morales, Karni, Chen, Gold, Ronit, Kay, Sigi, Glait-Santar, Chen, Eshel, Rinat, Perry, Chava, Avivi, Irit, Apel, Arie, Benyamini, Noam, Shasha, David, Ben-Ami, Ronen
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.09.2021; The American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc
• Subjects: CART; COVID-19; Full Length; HCT; Vaccination; COVID-19; HCT; Vaccination; CART
• ISSN: 2666-6367; 2666-6375; 2666-6367
• DOI: 10.1016/j.jtct.2021.06.024

Data are scarce regarding both the safety and immunogenicity of the BNT162b2 mRNA COVID-19 vaccine in patients undergoing immune cell therapy; thus, we prospectively evaluated these two domains in patients receiving this vaccine after allogeneic hematopoietic cell transplantation (HCT; n = 66) or after CD19-based chimeric antigen receptor T cell (CART) therapy (n = 14). Overall, the vaccine was well tolerated, with mild non-hematologic vaccine-reported adverse events in a minority of the patients. Twelve percent of the patients after the first dose and 10% of the patients after the second dose developed cytopenia, and there were three cases of graft-versus-host disease exacerbation after each dose. A single case of impending graft rejection was summarized as possibly related. Evaluation of immunogenicity showed that 57% of patients after CART infusion and 75% patients after allogeneic HCT had evidence of humoral and/or cellular response to the vaccine. The Cox regression model indicated that longer time from infusion of cells, female sex, and higher CD19+ cells were associated with a positive humoral response, whereas a higher CD4+/CD8+ ratio was correlated with a positive cellular response, as confirmed by the ELISpot test. We conclude that the BNT162b2 mRNA COVID-19 vaccine has impressive immunogenicity in patients after allogeneic HCT or CART. Adverse events were mostly mild and transient, but some significant hematologic events were observed; hence, patients should be closely monitored.