Early Treatment With Sotrovimab Decreases Risk for Progression to Severe COVID-19

antibody proteins attack a corona virus
Immunoglobulin or antibody proteins attack a corona virus pathogen cell – 3d illustration
Researchers conducted a study to determine whether treatment with sotrovimab decreases the risk for severe disease progression among high-risk patients with mild-to-moderate COVID-19.

Treatment with sotrovimab, a pan-sarbecovirus monoclonal antibody, was found to decrease the risk for severe disease progression among high-risk patients with mild-to-moderate COVID-19, according to results of an ongoing, multicenter, double-blind, prospective phase 3 trial published in The New England Journal of Medicine.

In this study, investigators enrolled adult patients with at least 1 risk factor for severe disease progression who developed symptomatic SARS-CoV-2 infection within the past 5 days. Risk factors for severe disease progression included patients older than55 years age, and those with either diabetes requiring medication, obesity, chronic kidney disease, congestive heart failure, chronic obstructive pulmonary disease, or moderate-to-severe asthma. Investigators randomly assigned patients in a 1:1 fashion to receive either a single infusion of sotrovimab 500 mg or placebo on day 1 of the trial, followed by treatment at their physician’s discretion. The primary outcome was hospitalization for more than24 hours or death from any cause within 29 days after the infusion. Investigators also conducted a safety analysis analyzing adverse events and infusion-related reactions.

Among a total of 583 patients included in the intention-to-treat population, 291 received sotrovimab and 292 received placebo. Of patients in both treatment groups, 22% were aged 65 years and older, 7% were Black, 63% were Hispanic or Latino, and 42% had 2 or more risk factors for severe disease progression. The investigators found that 3 patients (1%) in the sotrovimab group vs 21 (7%) in the placebo group were hospitalized or died due to severe disease progression (relative risk reduction, 85%; 97.24% CI, 44-96; P =.002).

There were 868 patients included in the safety analysis, of whom 430 were in the sotrovimab group and 438 were in the placebo group. Adverse events were reported by 17% and 19% of patients in the sotrovimab and placebo groups, respectively, and the frequency of severe adverse events was decreased among those who received sotrovimab vs those who received placebo (2% vs 6%). Of note, the percentage of patients with infusion-related reactions was similar in both groups.

Study limitations included its small sample size of patients treated with sotrovimab, the absence of an analysis on treatment failure among those in the sotrovimab as only 3 were hospitalized, and the inability to determine the effect emerging autologous immunity may have had on the safety and efficacy of sotrovimab treatment.

“Given its in vitro activity against variants of concern, as well as its ability to neutralize other sarbecoviruses, we speculate that sotrovimab has the potential to remain therapeutically active even as SARS-CoV-2 continues to evolve,” the investigators concluded.

Disclosure: This research was supported by Vir Biotechnology and GlaxoSmithKline. Please see the original reference for a full list of disclosures.


Gupta A, Gonzalez-Rojas Y, Juarez E et al. Early treatment for Covid-19 with SARS-CoV-2 neutralizing antibody sotrovimab. N Engl J Med. Published online October 27, 2021. doi:10.1056/NEJMoa2107934