Covid-19 patients in Singapore will be involved in an international trial to test an antibody treatment for the coronavirus infection.

The National Centre for Infectious Diseases (NCID) said in a statement yesterday that it is ready to enrol the first patients for the monoclonal antibody treatment trial. It did not indicate how many will be involved in the trial or when they will join the trial.

A monoclonal antibody is a purified, highly active antibody that targets the spike protein of the coronavirus.

"Large-scale randomised controlled trials have proved the effectiveness of remdesivir and dexamethasone in hospitalised patients with severe Covid-19," said Associate Professor David Lye, senior consultant and director of NCID's infectious disease research and training office.

"We clearly need more effective treatment options. Monoclonal antibodies are the next promising phase of Covid-19 treatment trials."

Patients on the trial will get either the antibody or a placebo, along with the antiviral drug remdesivir.

They may also be given dexamethasone - another proven treatment - if the doctor deems it suitable, he said.

NCID said it will focus on treating patients with pneumonia and a smaller group who needs oxygen.

The monoclonal antibody was developed by American pharmaceutical company Eli Lilly. Phase one trials have shown that it is safe and can improve patients' symptoms and reduce their viral load.

Named Activ-3, the trial which started in August has recruited over 200 Covid-19 patients, mainly from the United States and Denmark.

On Tuesday, The Straits Times reported that one of the two antibodies in the cocktail used to treat US President Donald Trump for Covid-19 was developed using blood samples from three patients in Singapore.

NCID has yet to comment on whether its current trial is linked to the earlier development.