Gilead’s coronavirus treatment is barreling its way into new clinical trials

At the beginning of February, Gilead Sciences struck a partnership with Beijing’s China-Japan Friendship Hospital to test its experimental antiviral remdesivir on patients with COVID-19, the respiratory ailment caused by the novel coronavirus strain. On Tuesday, the National Institutes of Health (NIH) confirmed the drug was undergoing human clinical trials in the U.S. as well—the first of their kind in America. And just one day later, Gilead announced it was launching two other late-stage studies of remdesivir across multiple countries as the coronavirus spreads globally.

Remdesivir’s unusually rapid advance across the clinical trial process highlights the urgent nature of the coronavirus outbreak’s public health threat—and the promise that regulators and global health agencies have credited to the treatment.

The two phase 3 clinical trials Gilead announced on Wednesday will enlist about 1,000 patients who have already contracted COVID-19. The participants will mostly be in Asia, the heaviest-hit region in a global health emergency that originated in China, although other nations with a high number of cases will also be involved. The trials are set to launch in March.

Phase 3 clinical trials are the precursors to ultimate regulatory approval for a treatment. They’re meant to confirm that a medicine is both safe and effective by expanding its reach to a larger pool of patients than those who participate in earlier-stage trials.

In remdesivir’s case, Gilead says that the new pair of trials will test out two different dosing regimens for the drug. One group with more severe forms of the disease will get the antiviral intravenously for either five or ten days. (The length of time will be randomized.)

Another group with more moderate forms of COVID-19 will either get the treatment for five or 10 days, or receive existing treatments that are already on the market and used for other strains of coronavirus. The breakup is meant to assess whether or not Gilead’s treatment is a significant improvement over the antivirals currently being administered to those with a milder form of the disease.

“This complementary array of studies helps to give us a more expansive breadth of data globally on the drug’s profile in a short amount of time,” said Dr. Merdad Parsey, chief medical officer at Gilead, in a statement.

Gilead’s therapy isn’t a coronavirus vaccine, but it has been hailed by public health officials as the most promising therapy to date for treating the disease caused by the pathogen—and an effective treatment for those who are already sick could buy drug makers crucial time to develop vaccines should the virus become endemic to the world.

“There is only one drug right now that we think may have real efficacy and that’s remdesivir,” said WHO assistant director-general Bruce Aylward during a press conference in Beijing on Monday.

Gilead stock soared nearly 7% in Wednesday trading.

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