Phase II/III trial of REGEN-COV meets primary endpoint in COVID-19.

Results show that REGEN-COV significantly reduced viral load in patients hospitalized with COVID-19 who entered the trial without having mounted their own antibody response (seronegative) and required low-flow or no supplemental oxygen (p=0.0172). The trial also had clinical results supportive of the much larger UK RECOVERY trial in hospitalized patients, with numeric improvements observed across all clinical endpoints assessed.

The trial, which was stopped due to slow enrollment after recruiting just over one third the patients originally planned, found that patients who received REGEN-COV (2,400 mg or 8,000 mg) in addition to standard-of-care (SOC) experienced numeric improvements across all clinical endpoints assessed, compared to SOC alone (placebo). Researchers did not observe any clinical difference between the two REGEN-COV doses (2,400 mg or 8,000 mg), or any serious or dose-dependent safety signals in REGEN-COV treated patients.

In a safety analysis involving 2,007 patients (REGEN-COV=1,340, placebo=667) serious adverse events occurred in 21% REGEN-COV patients (n=285) and 26% placebo patients (n=174). Infusion-related reactions and hypersensitivity reactions that were grade at least 2 occurred more commonly among REGEN-COV patients (2% and 1% respectively) than placebo patients (1% and <0.5% respectively). the trial originally assessed a broader group of patients; however in late 2020 the trial was adjusted to exclude patients who were on mechanical ventilation or high-flow oxygen at baseline based on a potential safety signal identified by an independent data monitoring committee in 199 patients on mechanical ventilation or high flow-oxygen, a finding that was not replicated in the much larger recovery trial that enrolled hospitalized patients with a broad range of severe covid-19, including these patient groups. trial results will be presented at idweek 2021.></0.5%>