Fauci: Pausing vaccine trial for safety review is "not uncommon at all"

Anthony Fauci said on Wednesday that it's "not uncommon at all" for a vaccine maker to pause its trials to review safety concerns, following news that AstraZeneca had done so on its phase 3 coronavirus vaccine trials due to a participant having a severe adverse reaction.

Driving the news: AstraZeneca, one of the frontrunners in the global race for a COVID-19 vaccine, said on Tuesday that the patient is expected to recover but did not make clear what the reaction was.

• "In large trials illnesses will happen by chance but must be independently reviewed to check this carefully. We are working to expedite the review of the single event to minimize any potential impact on the trial timeline," the company said in a statement.

What they're saying: "I think it's important to point out that that's the reason why you have various phases of trials, to determine if in fact these candidates are safe, Fauci said on CBS News. "It's really one of the safety valves that you have on clinical trials such as this."

• "It's not uncommon at all," Fauci added. "We see this generally, for the most part, but you don't know until you investigate it — it's an adverse event that's related to something else that just happened to have occured during the period of time that the clinical trial was on."
• "But you can't presume that. You always make the presumption that it's due directly to the actual vaccine ... This is an example of the kind of thing that you do to make sure we're dealing with a product that's safe."

The big picture: Multiple COVID-19 vaccines have moved on to phase 3 trials, but some worry the process has been rushed and could be susceptible to political pressure.

• Food and Drug Administration Commissioner Stephen Hahn has said he would be willing to fast-track the vaccine via an emergency use authorization before phase 3 trials conclude, but insisted he would not do so for political reasons.