WASHINGTON • The United States has begun late-stage clinical trials of a drug formulated to fight Covid-19, officials said on Tuesday.

The medicine is an antibody against the new coronavirus called LY-CoV555, which was identified in the blood sample of a recovered patient by Canada's Abcellera Biologics. It was then developed synthetically for mass production by US-based Lilly Research Laboratories in partnership with Abcellera.

The phase three trial will initially enrol some 300 volunteers around the world who have been hospitalised with mild to moderate Covid-19 with fewer than 13 days of symptoms.

Each will be assigned either the medicine, which will be injected intravenously, or a placebo.

Patients will also receive standard care for Covid-19, including the antiviral remdesivir.

The new phase three trial could expand to up to 1,000 people, including the more severely ill, if LY-CoV555 appears safe and effective after the fifth day.

The trial's main goal is the patients' sustained recovery for 14 days after release from the hospital.

At the same time, the new drug is also being tested on people with mild to moderate symptoms of Covid-19 who have not been hospitalised, as part of a parallel middle-stage trial also announced on Tuesday.

AGENCE FRANCE-PRESSE