Table 1. Baseline Characteristics of the Patients.*.
| Characteristic | Tocilizumab (N=161) |
Placebo (N=82) |
All Patients (N=243) |
|---|---|---|---|
| Enrolling hospital — no. (%) | |||
| Boston Medical Center | 16 (10) | 7 (9) | 23 (9) |
| Brigham and Women’s Hospital | 17 (11) | 8 (10) | 25 (10) |
| Lahey Hospital | 2 (1) | 2 (2) | 4 (2) |
| Massachusetts General Hospital | 62 (39) | 30 (37) | 92 (38) |
| North Shore Medical Center | 51 (32) | 26 (32) | 77 (32) |
| Newton–Wellesley Hospital | 13 (8) | 7 (9) | 20 (8) |
| St. Elizabeth’s Medical Center | 0 | 2 (2) | 2 (1) |
| Median age (IQR) — yr | 61.6 (46.4–69.7) | 56.5 (44.7–67.8) | 59.8 (45.3–69.4) |
| Age >65 yr — no. (%) | 60 (37) | 22 (27) | 82 (34) |
| Male sex — no. (%) | 96 (60) | 45 (55) | 141 (58) |
| Race or ethnic group — no. (%)† | |||
| American Indian or Alaska Native | 1 (1) | 0 | 1 (<1) |
| Asian | 7 (4) | 2 (2) | 9 (4) |
| Black | 24 (15) | 16 (20) | 40 (16) |
| Native Hawaiian or Pacific Islander | 0 | 1 (1) | 1 (<1) |
| White | 71 (44) | 33 (40) | 104 (43) |
| Other | 35 (22) | 15 (18) | 50 (21) |
| Unknown | 23 (14) | 15 (18) | 38 (16) |
| Hispanic or Latino ethnic group — no. (%)† | |||
| Hispanic or Latino | 70 (43) | 39 (48) | 109 (45) |
| Not Hispanic or Latino | 84 (52) | 35 (43) | 119 (49) |
| Unknown | 7 (4) | 8 (10) | 15 (6) |
| Median BMI (IQR)‡ | 29.9 (26.0–34.2) | 30.2 (25.7–33.8) | 30.1 (25.9–34.2) |
| BMI ≥30 — no. (%)‡ | 80 (50) | 42 (51) | 122 (50) |
| Median time from symptom onset to randomization (IQR) — days | 9.0 (6.0–13.0) | 10.0 (7.0–13.0) | 9.0 (6.0–13.0) |
| Hypertension — no. (%) | 80 (50) | 38 (46) | 118 (49) |
| Heart failure — no. (%) | 17 (11) | 7 (9) | 24 (10) |
| History of myocardial infarction — no. (%) | 15 (9) | 6 (7) | 21 (9) |
| Chronic obstructive pulmonary disorder — no. (%) | 15 (9) | 7 (9) | 22 (9) |
| Asthma — no. (%) | 15 (9) | 7 (9) | 22 (9) |
| Smoking status — no. (%) | |||
| Current smoker | 7 (4) | 0 | 7 (3) |
| Former smoker | 46 (29) | 26 (32) | 72 (30) |
| Lifelong nonsmoker | 99 (61) | 48 (59) | 147 (60) |
| Unknown | 9 (6) | 8 (10) | 17 (7) |
| Diabetes — no. (%) | 45 (28) | 30 (37) | 75 (31) |
| Chronic kidney disease — no. (%) | 29 (18) | 13 (16) | 42 (17) |
| History of cancer — no. (%) | 22 (14) | 8 (10) | 30 (12) |
| Ordinal scale score — no. (%)§ | |||
| 2 | 23 (14) | 15 (18) | 38 (16) |
| 3 | 133 (83) | 61 (74) | 194 (80) |
| 4 | 5 (3) | 5 (6) | 10 (4) |
| 5 | 0 | 1 (1) | 1 (<1) |
| Median laboratory values (IQR)¶ | |||
| Absolute lymphocyte count — cells/mm3 | 1040 (700–1400) | 1030 (680–1360) | 1030 (700–1400) |
| C-reactive protein level — mg/liter | 116.0 (67.1–190.6) | 94.3 (58.4–142.0) | 110.0 (64.9–175.3) |
| Ferritin level — ng/ml | 723 (413–1212) | 686 (382–1228) | 708 (411–1225) |
| d-Dimer level — ng/ml | 857 (536–1695) | 980 (500–1739) | 884 (527–1730) |
| Lactate dehydrogenase level — U/liter | 351 (287–420) | 324 (290–395) | 340 (289–413) |
| Serum interleukin-6 level — pg/ml | 23.6 (14.0–49.9) | 25.4 (14.6–40.3) | 24.4 (14.1–45.5) |
| Erythrocyte sedimentation rate — mm/hr | 61 (42–90) | 63 (42–87) | 61 (42–88) |
| Troponin level — ng/liter | 8 (6–22) | 9 (6–24) | 9 (6–22) |
| NT-proBNP level — pg/ml | 110 (50–438) | 93 (33–431) | 108 (38–437) |
| Procalcitonin level — ng/ml | 0.2 (0.1–0.4) | 0.2 (0.1–0.3) | 0.2 (0.1–0.4) |
Percentages may not total 100 because of rounding. IQR denotes interquartile range, and NT-proBNP N-terminal pro–B-type natriuretic peptide.
Race and ethnic group were reported by the patients.
The body-mass index (BMI) is the weight in kilograms divided by the square of the height in meters.
Scores on the ordinal clinical improvement scale range from 1 to 7, with higher scores indicating worse clinical condition. A score of 2 indicates that the patient was in (or ready for) a non–intensive care unit (ICU) hospital ward and was not receiving supplemental oxygen; a score of 3, that the patient was in (or ready for) a non-ICU hospital ward and was receiving supplemental oxygen; a score of 4, that the patient was in the ICU or in a non-ICU hospital ward and was receiving noninvasive ventilation or high-flow oxygen; and a score of 5, that the patient was in the ICU, intubated, and receiving mechanical ventilation.
Absolute lymphocyte counts were missing for 2 patients (1 in the tocilizumab group and 1 in the placebo group), C-reactive protein levels were missing for 2 patients (1 and 1), ferritin levels were missing for 1 patient (in the placebo group), d-dimer levels were missing for 2 patients (1 and 1), lactate dehydrogenase levels were missing for 3 patients (1 and 2), interleukin-6 levels were missing for 9 patients (6 and 3), erythrocyte sedimentation rates were missing for 24 patients (19 and 5), troponin levels were missing for 9 patients (5 and 4), NT-proBNP levels were missing for 19 patients (12 and 7), and procalcitonin levels were missing for 16 patients (8 and 8).