TABLE 7.
Protection of monkeys immunized with ChimeriVax-DEN1-4 tetravalent formulations and challenged with heterologous WT DEN1 virusa
| Group | Monkey | Vaccine formulation | Viremia by day postchallenge:
|
PRNT50
|
||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | Prechallengec | Postchallenged | |||
| 5 | F20967F | 5,5,5,5 | 0b | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 160 | 5,120 |
| F21501M | 3,5,5,3 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 40 | 20,480 | |
| F21784F | 5,5,5,3 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 40 | 20,480 | |
| F18172F | 3,3,3,3 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 80 | 20,480 | |
| F21149M | 5,5,5,3 | 0 | 0 | 0 | 0 | 2.0 | 3.0 | 3.3 | 1.7 | 0 | 0 | 20 | 20,480 | |
| F21570F | 3,3,3,3 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 160 | 10,240 | |
| 6 | F20928M | None | 0 | 1.0 | 1.7 | 2.7 | 3.0 | 2.8 | 0 | 0 | 0 | 0 | <10 | 2,560 |
| F22673F | None | 0 | 0 | 1.0 | 1.3 | 2.9 | 3.3 | 3.2 | 1.7 | 0 | 0 | <10 | 1,280 | |
| F21753M | None | 0 | 0 | 2.0 | 2.7 | 2.9 | 3.4 | 3.4 | 1.7 | 1.0 | 0 | <10 | 2,560 | |
| F21143F | None | 0 | 1.0 | 1.7 | 1.7 | 2.5 | 3.3 | 2.6 | 0 | 0 | 0 | <10 | >10,240 | |
a
All monkeys were challenged with 5 log units of DEN1 virus (West Pacific 74, nonattenuated), with the exception of monkeys F20928M and F22673F, which received 4 log units of challenge virus (pilot study).
b
No virus could be detected when serum was tested in the plaque assay at undiluted, 1:2, or 1:10 dilutions; limit of detection, 1 log10 PFU/ml.
c
180 days postvaccination.
d
30 days postchallenge (day 210).