Regeneron, which expects data from REGN-COV2 in humans next month after it prevented and treated the disease in animals, would handle U.S. sales and Roche worldwide distribution should it win approval, the companies said on Wednesday.

Roche has one of the world's largest antibody production operations, including U.S. facilities in San Francisco, and will boost overall capacity for REGN-COV2 by at least three and a half times, a feat Regeneron would have been hard pressed to accomplish alone.

"This major collaboration with Roche provides important scale and global expertise to bring REGN-COV2 to many more patients in the United States and around the globe," Regeneron Chief Executive Leonard Schleifer said.

Roche's move to join up with Regeneron comes after its own drug, Actemra, failed in a trial against COVID-19.

The companies will fund and run ongoing late-stage Phase 3 prevention and earlier-stage Phase 1 healthy volunteer safety studies, as well as additional studies to evaluate REGN-COV2 in treating or preventing COVID-19.

The medicine combines one Regeneron-made antibody and a second antibody isolated from humans who recovered from COVID-19.

The combination is designed to bind to the spike protein used by the new coronavirus to gain access to human cells, limiting its ability to escape.

The United States already has a $450 million deal for the cocktail in place, under the terms of which Regeneron will sell it around 70,000 to 300,000 potential treatment doses or 420,000 to 1.3 million prevention doses of REGN-COV2.

In July, the U.S. Justice Department sent a letter clearing the way for drug companies, including Roche, to share information in order to increase manufacturing capacity for antibody treatments.

(Reporting by John Miller, Additional reporting by Michael Erman in Maplewood, N.J.; Editing by Michael Shields and Jan Harvey)

By John Miller