Table 2 Demographics and baseline characteristics in the Canadian subgroup pooled for two studies
Characteristic | 6 Amb a 1-U MK-3641 (n =112) | 12 Amb a 1-U MK-3641 (n =110) | Placebo (n =115) | |||
|---|---|---|---|---|---|---|
Female, n (%) | 51 (45.5) | 59 (53.6) | 49 (42.6) | |||
Age, mean (range), y | 36.2 (18.0–50.0) | 35.8 (19.0–51.0) | 36.9 (18.0–51.0) | |||
Race, n (%) | ||||||
White | 84 (75.0) | 93 (84.5) | 86 (74.8) | |||
Black or African American | 7(6.3) | 6 (5.5) | 7 (6.1) | |||
American Indian or Alaskan native | 2 (1.8) | 0 | 0 | |||
Asian | 17 (15.2) | 9 (8.2) | 20 (17.4) | |||
Multiracial | 2 (1.8) | 2 (1.8) | 2 (1.7) | |||
History of asthma, n (%) | 22 (19.6) | 23 (20.9) | 27 (23.5) | |||
Tobacco use, n (%) | 31 (27.7) | 24 (21.8) | 33 (28.7) | |||
Duration of ragweed allergy, mean, y | 18.5 | 17.4 | 17.4 | |||
Skin prick test, mean (SD) wheal measurement, mm | ||||||
Histamine positive control | n = 111 | 5.7 (1.66) | n = 108 | 5.7 (1.45) | n = 114 | 5.6 (1.60) |
Saline negative control | n = 111 | 0.7 (1.20) | n = 108 | 0.6 (1.04) | n = 114 | 0.5 (0.99) |
Ambrosia artemisiifolia extract | n = 111 | 12.2 (4.48) | n = 110 | 12.1 (3.96) | n = 115 | 11.8 (4.03) |
Serum sIgE ( Ambrosia artemisiifolia ), mean (SD) kU/L | n = 112 | 17. 8 (19.8) | n = 110 | 19.4 (23.4) | n = 115 | 20.4 (23.2) |
Polysensitized, n (%) | 95 (84.8) | 89 (80.9) | 90 (78.3) | |||