Table 1.
Summary of in vitro neutralization data of sera from individuals comparing geometric mean titers (GMT) after Omicron-updated vs. wild-type mRNA vaccines as fourth doses after three previous doses of mRNA vaccines (* after 2 previous doses of mRNA vaccines; # range 2–4 previous doses).
| In Vitro Neutralization Assay | n per Arm | Manufacturer | Median Follow-Up Duration | nAb Titer against BA.4/5 (Bivalent vs. Monovalent) | nAb Titer against BQ.1.1 (Bivalent vs. Monovalent) | Ref. |
|---|---|---|---|---|---|---|
| live virus | 12 | n.a. | 16–42 days | 11-fold increase (GMT 576) * 4-fold increase compared to 2 monovalent boosts |
6-fold increase (GMT 112; higher in 2 previously infected individuals) * 2-fold increase compared to 2 monovalent boosts |
[32] |
| 29 | Pfizer or Moderna | 1 month | 3-fold increase (GMT 298; 1558 in previously infected) | 3-fold increase (GMT 73; 267 in previously infected) | ||
| 40 (18–55) + 40 (older than 55) |
Pfizer | 1 week | no difference | n.a. | [65] | |
| 38 (18–55) + 36 (older than 55) | Pfizer | 1 month | 9.5-fold increase (GMT 606) in 18-55 2.9-fold increase (GMT 236) in older than 55 (higher in uninfected) |
n.a. | [14] | |
| pseudovirus | 21 | n.a | 3–5 weeks | 1.2 fold increase (GMT 1649) | n.a. | [31] |
| 18 (previously 33% infected) | 8 Pfizer 10 Moderna |
3 weeks | 1.3-fold increase (GMT 3693) # | 1.2-fold increase (GMT 406) # | [60] | |
| n.a. | [30,60] |