Just published: phase 3 results of an outpatient trial of Regn-Cov (USA; known as Ronapreve in the UK). Summary results may have been given before by press release, but here is the detail.
Interestingly, almost 70 % of the subjects had no detectable antobodies at baseline.
Administered in an outpatient setting, at both the higher and lower doses this drug reduced the risk of hospitalisation and death by approx 70 %.
NB study funded by Regeneron and others.
COVID-19 Antibody - Interpretation of Test Results 
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