Concerns raised yesterday by an advisory group to the U.S. Food and Drug Administration (FDA) may once again tap the brakes on Operation Warp Speed, the U.S. government’s $10.8 billion push to rapidly move candidate COVID-19 vaccines from concept to communities.

As new U.S. cases of the pandemic coronavirus set a daily high of more than 75,000, FDA’s Vaccines and Related Biological Products Advisory Committee (VRBPAC) held a 9-hour virtual meeting to discuss a regulatory pathway that could permit the widescale use of a COVID-19 vaccine that has only minimal evidence of safety and efficacy. A so-called emergency use authorization (EUA) could use preliminary data from vaccine efficacy trials now underway to shave many months off the standard approval process, and FDA wanted VRBPAC to weigh in about the wisdom of taking this shortcut. The hearing, live-streamed on YouTube, drew intense interest, and some of the committee members—a mix of academics, consumer representatives, and government scientists—had an unsettling but clear message to FDA: Hold your horses.

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