Table 1.
Baseline characteristics of the primary cohort
| Tixagevimab–cilgavimab group (n=710) | Placebo group (n=707) | ||
|---|---|---|---|
| Age, years | 55 (44–66) | 55 (44–66) | |
| Sex | |||
| Female | 299 (42%) | 295 (42%) | |
| Male | 411 (58%) | 412 (58%) | |
| Race or ethnicity | |||
| Non-Hispanic White | 360 (51%) | 344 (49%) | |
| Non-Hispanic Black | 177 (25%) | 175 (25%) | |
| Hispanic | 119 (17%) | 135 (19%) | |
| Asian | 34 (5%) | 24 (3%) | |
| Other | 20 (3%) | 29 (4%) | |
| Body-mass index in kg/m2 | |||
| 30–39·9 | 281 (40%) | 268 (38%) | |
| ≥40·0 | 102 (14%) | 106 (15%) | |
| Co-existing chronic illness* | |||
| Any | 415 (58%) | 445 (63%) | |
| Hypertension treated with medication | 292 (41%) | 300 (42%) | |
| Diabetes treated with medication | 183 (26%) | 187 (26%) | |
| Asthma | 68 (10%) | 70 (10%) | |
| Renal impairment | 63 (9%) | 70 (10%) | |
| Chronic obstructive pulmonary disease | 44 (6%) | 42 (6%) | |
| Immunocompromised† | 57 (8%) | 71 (10%) | |
| SARS-CoV-2 vaccination status‡ | |||
| Fully vaccinated | 103 (15%) | 101 (14%) | |
| Partially vaccinated | 82 (12%) | 90 (13%) | |
| Not vaccinated | 525 (74%) | 516 (73%) | |
| Days since symptom onset | 8 (6–10) | 8 (6–10) | |
| Medication use before randomisation | |||
| Remdesivir | 447 (63%) | 450 (64%) | |
| Corticosteroid | 518 (73%) | 517 (73%) | |
| Immunomodulator§ | 64 (9%) | 50 (7%) | |
| Antirejection medication | 24 (3%) | 32 (5%) | |
| Therapeutic dose anticoagulation¶ | 58 (8%) | 66 (9%) | |
| Prophylactic or intermediate dose anticoagulation | 467 (66%) | 470 (66%) | |
| Pulmonary ordinal scale category‖ | |||
| Not receiving supplemental oxygen | 174 (25%) | 155 (22%) | |
| Conventional supplemental oxygen <4 L/min | 241 (34%) | 270 (38%) | |
| Conventional supplemental oxygen ≥4 L/min | 216 (30%) | 200 (28%) | |
| High flow nasal cannula or non-invasive ventilation** | 79 (11%) | 82 (12%) | |
| Delta variant†† | 344/685 (50%) | 343/662 (52%) | |
| Genscript neutralising anti-spike antibody positive‡‡ | 380/687 (55%) | 339/676 (50%) | |
| BioRad anti-nucleocapsid antibody positive§§ | 417/687 (61%) | 444/677 (66%) | |
| Quanterix anti-spike immunoglobulin G positive¶¶ | 357/681 (52%) | 349/675 (52%) | |
| Nucleocapsid antigen concentration‖‖ | 1622 (299–4891) | 1675 (247–5287) | |
| Positive (concentration ≥3 pg/mL) | 645/687 (94%) | 642/676 (95%) | |
Data are median (IQR) or n (%).
Full list of co-existing chronic illness in the appendix (p 33).
Immunocompromised is defined as receiving anti-rejection medications, biologic medications to treat autoimmune disease or cancer (excluding interleukin[IL]-1, IL-6, janus kinase [JAK] inhibitors, and tumour necrosis factor [TNF] inhibitors), human immunodeficiency virus, or other immunosuppressive condition.
Fully vaccinated is primary vaccine series dose(s) completed at least 14 days before the onset of symptoms; partial vaccinated is primary vaccine series dose(s) completed within 14 days before onset of symptoms, or one dose received of a two-dose series; not vaccinated is first dose of vaccine received after onset of symptoms or no known vaccine doses received (eight with unknown vaccination status: two in the tixagevimab–cilgavimab group, six in the placebo group).
Immunomodulators. Overall, 58 participants received a JAK inhibitor, 41 received a IL-6 inhibitor, one received a IL-1 inhibitor, and one received a TNF inhibitor (see also appendix p 34).
Therapeutic anticoagulation was defined as receipt of therapeutic doses of heparin, warfarin, or a direct acting oral anticoagulant.
For participants on chronic supplemental oxygen therapy before COVID-19, categorisation on the pulmonary ordinal scale was based on oxygen flow rates above the pre-COVID-19 oxygen flow rate.
On July 19, 2021, enrolment expanded to include participants receiving high flow nasal cannula or non-invasive ventilation.
SARS-CoV-2 delta variant was established from a mid-turbinate swab at baseline based on RT-PCR detection of the N-terminal domain of the delta spike. Of participants infected with the delta SARS-CoV-2 variant, 94% were enrolled July–September, 2021.
GenScript cPass surrogate SARS-CoV-2 neutralisation assay (anti-spike); positive was defined as ≥30% binding inhibition.
BioRad Platelia anti-nucleocapsid assay (total antibody); positive was defined as ≥1·0 sample:cutoff ratio.
Quanterix Simoa anti-spike assay (immunoglobulin G); positive was defined as ≥770 ng/mL.
Quanterix Simoa nucleocapsid antigen; positive was defined as ≥3 pg/mL.