Regeneron Pharmaceuticals has reported positive results from an ongoing Phase II/III seamless trial of investigational antibody cocktail, REGN-COV2, in the Covid-19 outpatient setting.

Data from the trial showed that REGN-COV2 significantly reduced viral load and patient medical visits, including hospitalisations, emergency room, urgent care visits and/or physician office/telemedicine visits.

Designed to block infectivity of SARS-CoV-2, REGN-COV2 is a combination of two monoclonal antibodies REGN10933 and REGN10987.

The randomised, double-blind trial is analysing the effect of adding REGN-COV2 to usual standard-of-care as compared to placebo.

Last month, Regeneron reported data from the descriptive analysis of the trial of REGN-COV2 showing it reduced viral load and the time to alleviate symptoms in non-hospitalised patients with Covid-19.

The latest data, involving an additional 524 patients, showed that the trial met all the first nine endpoints.

No significant difference in virologic or clinical efficacy between the 8g and 2.4g dose of REGN-COV2 was reported.

Regeneron Pharmaceuticals president and chief scientific officer George Yancopoulos said: “Today’s analysis, involving more than 500 additional patients, prospectively confirms that REGN-COV2 can indeed significantly reduce viral load and further shows that these viral reductions are associated with a significant decrease in the need for further medical attention.”

On the primary endpoint, the average daily change in viral load by day seven in patients with high viral load was a 0.68 log10 copies/mL greater reduction with REGN-COV2 versus placebo.

In the overall patient group with detectable virus at baseline, the average daily reduction in viral load by day seven was a 0.36 log10 copies/mL reduction with the antibody cocktail compared to placebo.

Treatment with REGN-COV2 reduced Covid-19 related medical visits by 57% by day 29.

Regeneron shared the latest data with the US Food and Drug Administration (FDA), which is reviewing an emergency use authorisation (EUA) submission for the low dose of REGN-COV2 in high-risk patients with mild-to-moderate Covid-19.