The U.S. Food and Drug Administration (FDA) is likely to restrict the use of COVID-19 antibody treatments from Regeneron and Eli Lilly as they are ineffective against the omicron variant, the Washington Post reported on Monday.

The FDA action will involve revising the emergency use authorizations for the monoclonal antibodies, the report said, citing two senior administration health officials.

However, the agency will not revoke the emergency use authorizations in case the drugs work against a future COVID-19 variant, according to the report.

The FDA did not immediately respond to a Reuters request for comment, while a Regeneron spokesperson said the regulator would provide any potential communication on the topic.

Lilly had no immediate comment but pointed to its statement from December saying its antibody candidate, bebtelovimab, maintains neutralization activity against all known variants of concern, including omicron.

The U.S. government in December paused distribution of the treatments and said the halt would continue until new data emerges on their efficacy against omicron, which has quickly become the dominant strain in the United States and several other countries.

U.S. health agencies, however, had said that GlaxoSmithKline and Vir Biotechnology's rival drug sotrovimab appeared to work against the variant and resumed shipments of the drug.

GSK and Vir Biotech are boosting production of their drug to help meet soaring demand in the United States.