FDA approves remdesivir as first coronavirus drug

The FDA on Thursday approved Gilead's coronavirus drug remdesivir — making it the only Covid-19 treatment to win full approval from U.S. regulators.

The agency based its decision on three randomized, controlled trials that showed remdesivir can reduce the length of hospital stays and the likelihood that patients will require oxygen. None of those trials, including a large study run by the National Institutes of Health, found that the drug could reduce the risk of death, however.

But the FDA's verdict is bound to be controversial, coming days after a major multi-country trial backed by the World Health Organization found that the drug showed "little to no effect" on hospitalized Covid-19 patients and did not reduce their risk of death or length of hospitalization.

"It's striking that a full approval happens right after we hear about data from the WHO trial that remdesivir has little effect in hospitalized patients," said Walid Gellad, director for the Center for Pharmaceutical Policy and Prescribing at the University of Pittsburgh.

Eric Topol, a public health expert who directs the Scripps Research Translational Institute, had a blunter assessment of the FDA's decision. "I don't think the data supports it," he said, noting the recent WHO trial results.

Instead of the FDA pushing Gilead to "do the darn trial to get the answer," Topol said, the decision means the "science will be absent."

The FDA did not mention the WHO trial in its risk-benefit assessment for remdesivir. In a separate Q&A on the approval, the agency said that the design of the NIH-run trial "was better suited to rigorously assess a time to recovery endpoint" than the WHO-backed trial was. The WHO study's results "do not refute" the findings of the NIH trial, the FDA added.

Merdad Parsey, Gilead's chief medical officer, said in an open letter Thursday that the data from the WHO trial "does not negate other study results," like those from the NIH trial.

And Francisco Marty, an infectious disease doctor at Brigham and Women's Hospital in Boston who worked on a Gilead-sponsored trial of remdesivir, said the data from the NIH trial was better quality than that from the WHO trial, "and it was done in the U.S."

The FDA, which normally convenes an independent advisory committee to review drugs prior to approval if there are questions about a treatment's efficacy or safety, did not do so for remdesivir. The agency said it was not necessary because Gilead's application for approval "did not raise significant safety or efficacy issues."

Background: The FDA has approved the use of remdesivir in adults and children over age 12 who are hospitalized with Covid-19.

The agency gave the drug an emergency-use authorization in May after preliminary data from the government trial, run by NIH's National Institute of Allergy and Infectious Diseases, showed that remdesivir cut the length of hospital stays.

Since then, thousands of patients — including President Donald Trump — have taken the drug.

Sweetening the deal: As part of its approval, the FDA awarded Gilead a priority review voucher that it can use or sell to other companies to speed the review of another drug. Remdesivir qualified for the voucher because the agency considers it a medical countermeasure to a material threat — in this case, the virus.

The voucher is potentially worth about $100 million.

Ripple effects? The approval for remdesivir could have wider implications for other potential Covid-19 treatments.

Gellad said that the approval could prevent the FDA from issuing emergency-use authorizations for other coronavirus treatments for hospitalized patients. That's because the agency can noly issue an EUA when no approved therapy is available.

But Rachel Sachs, an associate professor of law at Washington University in St. Louis, said she thinks it's unlikely as "the legal standards ('adequate,' 'available,' etc) leave room for more authorizations, especially for products that have different mechanisms of action or indications."

What's next: Multiple, international late-stage clinical trials are ongoing to further evaluate the safety and efficacy of remdesivir, known commercially as Veklury, in different patient populations, formulations, and in combination with other therapies.