LONDON (Reuters) - Scientists at Britain’s Oxford University have started a clinical trial to investigate the effects of an HIV medicine and a steroid drug in UK patients admitted to hospital with COVID-19 caused by the new coronavirus.

The first patients have already been enrolled for the trial within the country’s National Health Service, the researchers said on Monday.

It will test AbbVie’s Kaletra - a combination of lopinavir and ritonavir which is normally used to treat the Human Immunodeficiency Virus (HIV) that causes AIDS - and the steroid dexamethasone, which is used to reduce inflammation in a wide range of conditions.

The researchers stressed that while it was possible some existing drugs such as these may be beneficial in the fight against COVID-19, there was no guarantee they would be.

In a small-scale trial of just the HIV drug in patients in China with severe COVID-19, scientists found it “had no discernible effect” on the replication of the virus.

The British researchers, led by Peter Horby, a professor of emerging infectious diseases at Oxford, said that since the safety and side effects of both drugs are already known, the trial would focus on their potential against COVID-19 infection.

“Adults admitted to hospital with COVID-19 should be offered the opportunity to participate in this trial and contribute to improving care for everyone,” Horby said in a statement.

“All patients will receive the standard full medical care, regardless of which treatment group they are placed in.”

In future the trial will be expanded to test other potential treatments as they become available, the team said.