A formal clinical trial has begun into four drugs for the treatment of patients who have contracted Ebola. The drugs are designed to help the body's immune system fight against the virus after infection. CGTN's Daniel Ryntjes reports from Washington.

A trial that began last week in the Democratic Republic of Congo is designed to discover which of up to four drugs will be effective in treating patients with Ebola, according to the U.S. National Institutes of Health.

DR. ANTHONY FAUCI NATIONAL INSTITUTE OF ALLERGY AND INFECTIOUS DISEASE (USA) "We started a formal clinical trial to determine if this one is better than this one is better than this one."

The trial is a partnership between the Congolese health authorities and international partners, including the U.S. National Institutes of Health which has developed a treatment called mAb114.

DR. ANTHONY FAUCI NATIONAL INSTITUTE OF ALLERGY AND INFECTIOUS DISEASE (USA) "There was an individual among many who actually recovered from Ebola. We brought that individual who was a Congolese person, we brought them here to the United States. We drew their blood and from their blood we derived what is called a monoclonal antibody, a natural product that's an antibody protein that the body makes to protect itself against different types of infection."

There are two other antibody treatments developed by U.S.-based pharmaceutical companies Mapp and Regeneron, alongside an antiviral medicine called Remdesivir. All four treatments have been used by medical teams on the ground in the DRC for what's called "compassionate use".

DANIEL RYNTJES WASHINGTON DC "How long will it be before we know if this is something that is beyond promising?"

DR. ANTHONY FAUCI NATIONAL INSTITUTE OF ALLERGY AND INFECTIOUS DISEASE (USA) "So the only way you know is if you get a certain number of people who are infected who get treated with this one, versus this drug versus this. And then at the end of the trial, depending on how many people in the trial you'll know."

Given the level of instability in the outbreak area in the east of the DRC, it is likely to take months to develop a strong set of results.

DANIEL RYNTJES WASHINGTON DC "The study has been established so that researchers will need at least five hundred infections, and preferably more, to determine which drugs are most effective. Daniel Ryntjes, CGTN, Washington."