LLY Eli Lilly and Co

By Joseph Walker 

Regeneron Pharmaceuticals Inc. suspended testing of its Covid-19 antibody drug in the sickest hospitalized patients because of a safety concern, the latest setback for antibody-drug trials in patients with the most advanced disease.

Regeneron said Friday it is pausing enrollment of hospitalized Covid-19 patients receiving mechanical ventilation or high-flow oxygen, after an independent monitoring committee observed "a potential safety signal and an unfavorable risk/benefit profile at this time."

The committee recommended pausing enrollment of those patients until further data is collected and analyzed.

The moves don't affect other testing of the antibody drug, which proved in a separate trial to reduce virus levels and doctor visits. The drug is now up for authorization by the Food and Drug Administration, along with a similar drug from Eli Lilly & Co.

The Regeneron study will continue enrolling hospitalized patients receiving low amounts of oxygen or no oxygen support, who tend to be less sick than those who require heavy oxygen or mechanical breathing assistance. The company said the risk-benefit for the less serious hospitalized patients remains acceptable.

The committee also recommended that a study of the drug in patients who aren't hospitalized be continued without modification, the company said.

The partial study hold indicates that the promising class of monoclonal antibodies might not work in hospitalized patients with the most severe cases of Covid-19. On Monday, a study of Eli Lilly's monoclonal antibody in hospitalized patients was terminated after it was determined the drug was unlikely to provide a benefit.

Regeneron shares fell 2.3% to $542.29.

Earlier this month, President Trump received treatment with Regeneron's antibody drug, to which he later credited his recovery from Covid-19.

(END) Dow Jones Newswires

October 30, 2020 11:33 ET (15:33 GMT)

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