Serologic Responses following a Single Dose of SARS-Cov-2 Vaccination in Allogeneic Stem Cell Transplantation Recipients

Abstract

Immunocompromised individuals were not included in formal trials of SARS-CoV-2 mRNA vaccines. Subsequent studies in patients with haematological malignancies and solid organ transplant recipients suggest inferior responses to vaccination. We determined antibody responses to a single dose of vaccines in one of the most vulnerable patient groups, allogeneic haematopoietic cell transplant (allo-HCT) recipients. Pfizer-BioNTech or AstraZeneca SARS-CoV-2 vaccines were administered at least 3 months post-transplant to 55 adult allo-HCT recipients. We found that older age and concurrent use of immunosuppressive medications were significantly associated with lack of antibody response to vaccination. Only 21% of those on systemic immunosuppression mounted a response, compared to 58% of patients who were not taking immunosuppression (p=0.006). We also show that responses to the AstraZeneca vaccine may be superior to the Pfizer-BioNTech vaccine in this cohort. These findings highlight the need for novel immunogenic vaccine formulations and schedules in these highest risk patients as well as continued public healthy safety measures to protect the most vulnerable members of our society.

Serological response following BNT162b2 anti‐SARS‐CoV‐2 mRNA vaccination in haematopoietic stem cell transplantation patients

“…Older age and concurrent immunosuppression were significantly associated with lack of response. 14 Overall, our present study confirms that most of the transplanted patients respond to a complete vaccination cycle. Responders in the allogeneic group had even higher antibody levels than HC.…”

Predictors of Humoral Response to SARS-CoV-2 Vaccination after Hematopoietic Cell Transplantation and CAR T-cell Therapy

“…However, among patients with malignancies (10,11) and recipients of solid organ transplantation (12)(13)(14) emerging data suggest lower vaccine efficacy compared to the healthy population. Data for patients undergoing cellular therapies are sparse, with small studies reporting attenuated humoral and/or cellular immune responses (15)(16)(17). We therefore aimed to assess immune responses to mRNA COVID-19 vaccines among patients who underwent cellular therapies at our center, with the goal of identifying predictors of response, determining the ideal timing for vaccination, and to identify patients at high risk for non-protective immune responses who might benefit from additional doses ('boosters') of vaccines.…”

Vaccine Responses in Adult Hematopoietic Stem Cell Transplant Recipients: A Comprehensive Review

“…Only 1 article was included through snowballing. This resulted in 10 articles being suitable for this analysis, which are shown in Table 3 in order of timing of the vaccination post-HSCT [ 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 ].…”

“…This was also seen in the available response rates for COVID vaccination: 37–50% <12 months post-HSCT [ 48 , 56 ] versus 68–94% >12 months post-HSCT [ 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 ]. One study reported on vaccination < 6 months post-HSCT with only 12.5% response ( n = 8) [ 57 ]. In addition to timing, usage of immunosuppressants and active GVHD seem to be the most important factors influencing response.…”