Table 2.
The Immunogenicity at 4 Weeks after 2-dose of BNT162b2 mRNA COVID-19 (Pfizer) Vaccines
| Serologic parameters | On-therapy group (N=21) | Off-therapy group (N=22) | P-value* |
|---|---|---|---|
| Anti S-RBD total Ig (U/ml); GMT (95%CI) | 21.9 (4.5,106.1) | 2828 (2013,3971) | <0.001 |
| Anti S-RBD IgG (BAU/ml); GMT (95%CI) | 56.1 (13.1,238.2) | 3633 (2689,4908) | <0.001 |
| sVNT SARS-CoV-2 wild-type (%inhibition); median (IQR) | 18.4 (-19.6,83.8) | 99.3 (99.0,99.5) | <0.001 |
| sVNT SARS-CoV-2 delta (%inhibition); median (IQR) | 26 (5.8,73.5) | 97.1 (96.0,97.4) | <0.001 |
| Seroprotective rate#; N (%) | |||
| SARS-CoV-2 wild type | 7 (33.3) | 23 (100) | <0.001 |
| Delta strain | 7 (33.3) | 23 (100) | <0.001 |
*P-value corresponds to Mann-Whitney U and Chi-square test; #The seroprotective rate was defined as sVNT ≥ 68% adopted from the US-FDA guidance; S-RBD, Spike protein ribosomal-binding domain; sVNT, surrogated viral neutralization test