Table 2.
Measles Serologic Status Before and After Measles Vaccination in P1024
| Endpoint and Study Time Pointa | All Strata Combined | Stratum 2 | Stratum 3 | Stratum 4 |
|---|---|---|---|---|
| Percent with PRN ≥8 mIU/mL at entry (no. of subjects evaluated) | 83 (193) | 76 (63) | 81 (73) | 95 (57)b |
| (95% CI) | (77–88) | (64–86) | (70–89) | (85–99) |
| Percent with PRN ≥120 mIU/mL (no. evaluated) | ||||
| Week 0 | 52 (193) | 37 (63) | 49 (73) | 74 (57)c |
| (95% CI) | (45–60) | (25–50) | (37–61) | (60–84) |
| 8 wk post-MMR (study week 24) | 89 (193)d | 86 (63)d | 89 (73)d | 93 (57)d |
| (95% CI) | (84–93) | (75–93) | (80–95) | (83–98) |
| 32 wk post-MMR (study week 48) | 82 (185)d,e | 82 (61)e | 81 (69)e | 82 (55) |
| (95% CI) | (75–87) | (70–91) | (70–90) | (69–91) |
| 80 wk post-MMR (study week 96) | 80 (179)e | 76 (59)e | 77 (66)e | 89 (54)e |
| (95% CI) | (74–86) | (63–86) | (65–87) | (77–96) |
| Percent with ≥4-fold PRN rise, week 0 to 8 wk post-MMR (no. evaluated) | ||||
| Subjects with PRN <8 mIU/mL at entry | 78 (32) | 60 (15) | 93 (14) | 100 (3) |
| (95% CI) | (60–91) | (32–84) | (66–100) | (29–100) |
| Subjects with PRN ≥8 mIU/mL at entry | 37 (161) | 46 (48) | 37 (59) | 30 (54) |
| (95% CI) | (30–45) | (31–61) | (25–51) | (18–44) |
| Geometric mean antibody concentration, mIU/mL | ||||
| Week 0 | 108 | 47 | 86 | 360f |
| (95% CI) | (77–152) | (27–83) | (48–153) | (207–627) |
| 8 wk post- MMR (study week 24) | 695g | 571g | 627g | 983g |
| (95% CI) | (556–868) | (360–903) | (453–868) | (668–1445) |
| 32 wk post-MMR (study week 48) | 401g,h | 317g,h | 397g,h | 526g |
| (95% CI) | (312–515) | (188–536) | (282–558) | (336–825) |
| 80 wk post-MMR (study week 96) | 361g,h | 247g,h | 361h | 544 |
| (95% CI) | (279–467) | (145–423) | (255–510) | (343–864) |
Study MMR vaccine administered at study week 16. Immunologic strata are as follows: stratum 2, pre-HAART nadir CD4 cell percentage <15% and screening CD4 cell percentage ≥15%; stratum 3, pre-HAART nadir CD4 cell percentage 15% to <25% and screening CD4 cell percentage ≥15%; stratum 4, pre-HAART nadir CD4 cell percentage ≥25% and screening CD4 cell percentage ≥25%.
Abbreviations: CI, confidence interval; HAART, highly active antiretroviral therapy; MMR, measles-mumps-rubella vaccine; PRN, plaque reduction neutralization antibody concentration.
a Week 0 serological results were included if obtained any time prior to study MMR vaccine administration. Serological results at 8, 32, and 80 weeks post-vaccination (study weeks 24, 48, and 96) were included if they were obtained within windows of ±4, ±8, and ±12 weeks, respectively.
b P = .01 (Fisher's exact test) for the difference of the proportions with measles antibody concentration ≥8 mIU/mL among immune strata.
c P < .001 (Fisher's exact test) for the difference of the proportions with measles antibody concentration ≥120 mIU/mL among immune strata. Pairwise comparisons between stratum 4 and strata 2 and 3 were statistically significant (P ≤ .007), but pairwise comparisons between strata 2 and 3 were not.
d P ≤ .004 (McNemar test) for the comparison of the proportion of subject with measles antibody concentration ≥120 mIU/mL vs the previous time point.
e P ≤ .04 (McNemar test) for the comparison of the proportions of subjects with measles antibody concentration ≥120 mIU/mL at 32 weeks postvaccination (study week 48) and 80 weeks postvaccination (study week 96) vs week 0.
f P < .001 (t test) for the difference among immune strata. Pairwise comparisons between stratum 4 and strata 2 and 3 were statistically significant (P < .001), but pairwise comparisons between strata 2 and 3 were not.
g P ≤ .02 (paired t test) for the comparison of geometric mean antibody concentration vs the previous timepoint.
h P < .001 (paired t test) for the comparison of geometric mean antibody concentration at 32 weeks postvaccination (study week 48) and 80 weeks postvaccination (study week 96) vs week 0.