Table 1.
Baseline Demographic and Clinical Characteristics of Study Participants at Week 4.
| All | BNT162b2 | Unvaccinated | p a | |
|---|---|---|---|---|
| Total, n (%) | 505 | 260 | 245 | |
| Age, years | ||||
| Mean, SD | 46.3 (15.5) | 50.0 (16.0) | 42.4 (14.0) | <0.001 |
| 18–29 | 76 (15.0%) | 28 (10.8%) | 48 (19.6%) | <0.001 |
| 30–49 | 220 (43.6%) | 99 (38.1%) | 121 (49.4%) | |
| 50–64 | 125 (24.8%) | 69 (26.5%) | 56 (22.9%) | |
| ≥65 | 84 (16.7%) | 64 (24.6%) | 20 (8.2%) | |
| Gender | 0.086 | |||
| Female | 357 (70.7%) | 173 (66.5%) | 184 (75.1%) | |
| Male | 144 (28.5%) | 84 (32.3%) | 60 (24.5%) | |
| Unknown | 4 (0.8%) | 3 (1.2%) | 1 (0.4%) | |
| Race/Ethnicity | 0.006 | |||
| White or Caucasian | 305 (60.4%) | 168 (64.6%) | 137 (55.9%) | |
| Black or African American | 40 (7.9%) | 15 (5.8%) | 25 (10.2%) | |
| Hispanic | 73 (14.5%) | 26 (10.0%) | 47 (19.2%) | |
| Asian | 49 (9.7%) | 31 (11.9%) | 18 (7.4%) | |
| Other | 38 (7.5%) | 20 (7.7%) | 18 (7.4%) | |
| US Geographic Region | 0.053 | |||
| Northeast | 68 (13.5%) | 38 (14.6%) | 30 (12.2%) | |
| South | 201 (39.8%) | 89 (34.2%) | 112 (45.7%) | |
| Midwest | 113 (22.4%) | 67 (25.8%) | 46 (18.8%) | |
| West | 123 (24.4%) | 66 (25.4%) | 57 (23.3%) | |
| Social vulnerability index, Mean (SD) b | 0.44 (0.23) | 0.39 (0.22) | 0.49 (0.23) | <0.001 |
| Previously tested positive | 204 (40.4%) | 98 (37.7%) | 106 (43.3%) | 0.202 |
| Live or work in high-risk setting | 25 (5.0%) | 10 (3.9%) | 15 (6.1%) | 0.239 |
| Work in healthcare | 75 (14.9%) | 33 (12.7%) | 42 (17.1%) | 0.160 |
| Self-reported comorbidity | ||||
| Number of comorbidities, Mean (SD) | 0.38 (0.75) | 0.46 (0.79) | 0.30 (0.70) | 0.015 |
| Asthma or chronic lung disease | 25 (5.0%) | 17 (6.5%) | 8 (3.3%) | 0.090 |
| Immunocompromised conditions or weakened immune system c |
2 (0.4%) | 1 (0.4%) | 1 (0.4%) | 0.966 |
| Diabetes | 27 (5.4%) | 17 (6.5%) | 10 (4.1%) | 0.220 |
| Heart conditions or hypertension | 79 (15.6%) | 49 (18.8%) | 30 (12.2%) | 0.041 |
| Overweight or obesity | 60 (11.9%) | 36 (13.8%) | 24 (9.8%) | 0.160 |
| At least 1 comorbidity | 127 (25.1%) | 81 (31.2%) | 46 (18.8%) | 0.001 |
| Mean days since last vaccine dose, SD | 337 (209) | 165 (46) | 546 (121) | <0.001 |
| Nirmatrelvir/Ritonavir use, n (%) | 116 (23.0%) | 74 (28.5%) | 42 (17.1%) | 0.003 |
| Acute COVID-19 symptoms on index day d | 505 (100%) | 260 (100%) | 245 (100%) | |
| Mean number of symptoms, SD | 5.3 (2.3) | 5.0 (2.3) | 5.7 (2.3) | 0.001 |
SD: Standard Deviation; CMS: Centers for Medicare and Medicaid Services; IQR: Interquartile Range.a p value for the comparison between BNT162b2 and Unvaccinated. b SVI is a score that ranges from 0 to 1. Higher values correspond to higher vulnerability. c Immunocompromised conditions comprise conditions that result in a weakened immune system, including kidney failure or end stage renal disease, and indicators of compromised immune system (such as from the use of immune-compromising drugs, solid organ or blood stem cell transplant, HIV, or other conditions). d The index day is the day of receipt of the COVID-19 test nasal swab test.