The Food and Drug Administration authorised use of the Regeneron Pharmaceuticals Inc. antibody drug to try to prevent hospitalisation and worsening disease developing in patients with mild-to-moderate symptoms.

The drug is given as a one-time treatment through an IV. The FDA allowed its use in adults and children 12 and over who weigh at least 40 kilograms and who are at high risk of severe illness from COVID-19 because of age or other medical conditions.

Emergency authorisation allows use of the drug to start while studies are continuing to establish safety and effectiveness. Early results suggest the drug may reduce COVID-19-related hospitalisation or emergency room visits in patients at high risk for disease progression, the FDA said.

Regeneron said that initial doses will be made available to roughly 300,000 patients through a federal government allocation program. Those patients will not be charged for the drug but may have to pay part of the cost of giving the IV.

Initial supplies will likely be vastly outstripped by demand as the US has surged past 12 million reported cases, with the country facing what health experts say will be a dark winter due to uncontrolled spread of the virus.

The Regeneron drug is a combination of two antibodies to enhance the chances it will prove effective. Earlier this month, the FDA gave emergency authorisation to a single-antibody drug from Eli Lilly that also is still being studied.

There's no way to know whether the Regeneron drug helped Trump recover; he received a host of treatments and most COVID-19 patients recover on their own..

The White House cast the decision as a victory for Trump's efforts "to deliver cutting-edge treatments with highly promising results to protect the health and safety of the most vulnerable Americans," according to a statement from spokesman Michael Bars.

Australian Associated Press