Bnt162b2

COVID-19 convalescent patients were defined as study participants who had tested positive for SARS-CoV-2 by nasal swab PCR test in the past. All the COVID-19 convalescent patients in this study had received 2 doses of mRNA COVID-19 vaccines. The term vaccine recipient refers to participants who had never tested positive for SARS-CoV-2 and had received 2 doses of mRNA COVID-19 vaccines. All study participants worked in health care and/or laboratory settings; 33 participants received the Pfizer-BioNTech (BNT162b2) vaccine, and 5 participants received the Moderna (mRNA-1273) vaccine. Of all participants, 21 were between the ages of 21 and 30 years, 7 were between the ages of 31 and 40 years, 8 were between the ages of 41 and 50 years, and 2 were between the ages of 51 and 60 years. Blood was drawn and processed between June and August 2021. Further details for participants who responded to the S_812-829 epitope are in Table 2.

Flow cytometry and Luminex-based single-antigen bead assay were used to select the immunosuppressive therapy protocol^{27 (link)}. Basic immunosuppression included the use of calcineurin inhibitors (CNIs), MMF, steroids, and anti-CD25 monoclonal antibody basiliximab. Low-dose rituximab (100 mg/m² or 100 mg/body) was administered in recipients who had donor-specific human leukocyte antigen antibodies. ABO blood-type incompatible KT recipients received basic immunosuppressive agents, rituximab, low-dose rituximab (100 mg/m² or 100 mg/body), and therapeutic apheresis. Those with a viral infection or malignancies were switched from CNIs or MMF to everolimus. Page 8 line 225.
The mRNA vaccine was administered as a mass or individual vaccination; the Pfizer/BioNTech BNT162b2 was used for the first and second doses (0.03 mg/0.3 mL, deltoid muscle injection), and Moderna mRNA-1273 was also used from the third dose (0.05 mg/0.25 mL, deltoid muscle injection), but mostly Pfizer was used more frequently. The first dose was started on February 17, 2021; the second dose was given 3 weeks apart, starting on March 10, 2021; the third dose began on December 1, 2021. The third vaccination was recommended 6–8 months after the second dose by government policy due to vaccine shortages and preparation.

Between June 2020–April 2021, 102 individuals 18 years of age or older (70 COVID-19-naïve, 32 COVID-19-experienced) gave written informed consent to participate in this prospective study, which was approved by the Loyola University Chicago Institutional Review Board (IRB# 213447032320 and 214521021621). Subjects were defined as COVID-19-naïve or COVID-19-experienced based on three criteria: self-reported history of a SARS-CoV-2-positive test, pre-existing antibodies against spike, and/or pre-existing antibodies against nucleocapsid. All subjects received either Pfizer (BNT162b2) or Moderna (mRNA-1273) mRNA vaccines. Peripheral venous blood and demographic/clinical questionnaire data were collected at three study visits: baseline (PV), 3 weeks post-initial vaccine dose (V1), and 3 weeks after the second vaccine (V2). Cohort demographics are provided in Table 1.

The CACOV-VAC study (NCT04836793) was a monocentric prospective study, including cancer patients with active treatment in the adjuvant or metastatic setting, patients in surveillance, and healthy donors. The cut-off age of 70 years was chosen according to the ESMO-SIOG definition as the most commonly used cut-off for defining patients as elderly within the field of geriatric oncology (25 ). Men or women ≥ 18 years of age were eligible for inclusion if they had been eligible for the vaccination against SARS-CoV-2 with mRNA vaccine (Pfizer: BNT162b2; Moderna: mRNA-1273) and did not develop a symptomatic form of COVID-19 within the last 3 months before inclusion. Major exclusion criteria included the reception of a live, attenuated vaccine within 4 weeks before the initiation of treatment or if this vaccination will be required during the study. Here, we report the results of an ancillary study of the CACOV-VAC trial.

We studied second doses of BNT162b2 (Pfizer-BioNTech),¹⁹ (link) ChAdOx1 (Oxford-AstraZeneca),²⁰ (link) and mRNA-1273 (Moderna)¹² (link) vaccines, and third or booster doses of BNT162b2 and mRNA-1273. Vaccination status was defined on the date of the positive RT-PCR (symptom date for test-negative design) test and coded using the following categories: unvaccinated; 1–27 days after first dose; 28 days or more after first dose; 0–13 days after second dose; 14–41 days after second dose; 42–69 days after second dose; and 10 weeks or more (≥70 days) after second dose. For those with a third or booster dose, the categories were 0 or 1 week after booster dose or 2 or more weeks after booster dose.
Vaccinated groups were stratified by time intervals since second and third doses of vaccine and whether infection was caused by delta (S-gene positive) or omicron (S-gene negative). The S-gene variable took one of five values, as follows: S-positive (delta), weak S-positive (usually also delta), S-negative (omicron), other, and unknown. Unknown corresponded to individuals who were tested in NHS laboratories (where S-gene status was unavailable) or who were tested in the Lighthouse laboratory, but the sample did not yield any cycle threshold values. Other corresponded to cycle threshold values that could not otherwise be classified.