Trial NCT04666441
Publication Portal Celhay C, JAMA Netw Open (2022) (results posted on registry)
Primary outcome on the report: Time-weighted average daily change from baseline (TWACB) in viral load (log10 copies per milliliter) to day 7, as measured by RT-qPCR of NP swab samples in patients who had a central laboratory–determined RT-qPCR positive test at baseline and were seronegative (ie, negative for anti-spike [S1] IgA, anti-spike [S1] IgG, and anti-nucleocapsid IgG)

Note: The risk of bias by domain corresponds to the highest risk of bias among outcomes by domain.
The overall risk of bias corresponds to the overall highest risk of bias assessed among outcomes.

Bias Author's judgement Support for judgement
Randomization
Low 		Quote: "Eligible patients were randomized according to a central randomization scheme using an interactive web response system."
Comment: Allocation sequence random.
Allocation sequence concealed
Imbalances in baseline characteristics appear to be compatible with chance
Deviations from intervention
Low 		Quote: “Double-blind. Health care professionals, patients, and caregivers were blinded to placebo and to the doses of casirivimab and imdevimab, but not to the route of administration. ”
Comment: Blinded study (participants and personnel/carers)
Our analysis for the binary outcome is an intention-to-treat analysis. This method was considered appropriate to estimate the effect of assignment to intervention.
Risk assessed to be low for the outcomes: Mortality (D28). Mortality (D60 or more). WHO score 7 and above (D28). WHO score 7 and above (D60 or more). Serious adverse events.
Missing outcome data
Low 		Comment: 413 participants randomized; 6 participants missing data for safety outcomes; 7 additional missing data for negative conversion (not accounted for in domain 2)
Data available for all or nearly all participants randomized.
Risk assessed to be low for the outcomes: Mortality (D28). Mortality (D60 or more). WHO score 7 and above (D28). WHO score 7 and above (D60 or more). Serious adverse events.
Measurement of the outcome
Low 		Comment: Method of measuring the outcome probably appropriate.
Measurement or ascertainment of outcome probably does not differ between groups.
Blinded study (outcome assessor).
Risk assessed to be low for the outcomes: Mortality (D28). Mortality (D60 or more). WHO score 7 and above (D28). WHO score 7 and above (D60 or more). Serious adverse events.
Selection of the reported results
Low 		Comment: The protocol, statistical analysis plan, registry were available (registry consulted up to version dated December 14, 2020).
Outcome pre-specified.
Results were not selected from multiple outcome measurements or analyses of the data.
Trial analyzed as pre-specified.
Risk assessed to be low for the outcome: Mortality (D28). Mortality (D60 or more). WHO score 7 and above (D28). WHO score 7 and above (D60 or more). Serious adverse events.
Overall risk of bias
Low