A headlong race to come up with a viable vaccine for COVID-19 that is being championed by a science-averse American president seeking reelection prompted some skeptical questions Thursday on Capitol Hill.

The occasion was a confirmation hearing for Gen. Gustave Perna to lead Operation Warp Speed, the official moniker for the Trump administration's frenetic drive to roll out such a vaccine this year.

Perna is a four-star general who, as head of the U.S. Army Materiel Command, is the Army's most senior logistics officer. He was nominated last month by Trump to be the chief operating officer of Operation Warp Speed as well.

"The virus is our enemy and is impacting our way of life," Perna told members of the Senate Armed Services Committee who were there either physically or virtually to grill him. "If confirmed, I will dedicate myself to defeating this enemy."

Perna said when he was tapped for the job in mid-May, he initially thought the administration's goal of having a viable vaccine by the end of the year was merely aspirational.

"I have recently come to the conclusion that it is more and more likely to occur," Perna assured the panel. "The key to our success is to ensure we rely on science to assess our options, effectiveness and risk."

But New York Democrat Kirsten Gillibrand suggested election season politics may trump science for determining such a timetable.

"I'm concerned that Operation Warp Speed will be under pressure to release a vaccine before the election, but before adequate testing and research trials have been completed," Gillibrand told the general. "Could any sort of emergency use authorization be invoked to release the vaccine, even if in limited capacity, before those requirements have been met?"

Perna told the senator that determining the efficacy of a vaccine was the Food and Drug Administration's call.

"The decision to provide an emergency relief capability and/or deliver early is not my decision," he added. "That will be a policy decision."

Rhode Island's Jack Reed, the panel's ranking Democrat, also questioned the credibility of the administration's election-year dash for a vaccine. The FDA, he noted, could simply declare that a vaccine is ready, even if it had "a relatively low efficacy."

"We should understand, all of us, that the FDA has to demand rather significant efficacy for this drug before they say it's OK," Reed warned. "We want a vaccine, not a headline."

Still, Perna told the panel he thought the Trump administration's goal of having 100 million doses of a vaccine ready by November and another 200 million on hand by January was plausible.

"Right now, as I see the numbers," Perna told Connecticut Democrat Richard Blumenthal, "I do think it is potentially possible."

Citing Trump's unilateral break last month with the World Health Organization, Blumenthal pressed Perna on whether he would commit to working with any nation that offers information or cooperation for developing a COVID-19 vaccine.

"I commit to working with all nations that we deem are friendly to our national security," Perna replied.

Hawaii Democrat Mazie Hirono wanted to know if that included China.

"Right now, for me," the general responded, "it does not."

Noting that billions of dollars in contracts had already been awarded to at least five private pharmaceutical firms with little oversight, Hirono asked Perna if he would commit to briefing Congress every two weeks on Operation Warp Speed.

"Senator, I will report as directed," Perna told her, a reply that Hirono dismissed as "not making a commitment."

Maine Independent Angus King wanted to know what the price of a vaccine developed with public funds but produced by private industry should be.

"We're in negotiations with each company to make sure that we are going to obtain the right price for the vaccine," Perna assured King. "I commit to you that I will personally be involved in those conversations, and that we will not be gouged."

The logistics expert also acknowledged that several pharmaceutical firms that have received funding through Operation Warp Speed have not yet begun clinical trials in the U.S.

"Trials will begin for us 9 July with Moderna," he said, "followed by AstraZeneca and then Johnson & Johnson throughout the months of July, August, September."

Perna said another part of the effort he's to lead is identifying therapeutics capable of treating COVID-19. "We have some very promising candidates," he added, "that could be available as early as October, November."

Perna told the committee he did not have the authority to invoke the Defense Production Act, which some senators suggested could be used to require production by U.S. firms of needed supplies. But he said he felt "100% certain" either Defense Secretary Mark Esper or Health and Human Services Secretary Alex Azar could take such an action if he asked for it.

Mississippi Republican Roger Wicker told Perna there might be a simpler way to get fast results in the hunt for a vaccine.

"I would just ask you not to rule out among your bag of tools some sort of prize competition," Wicker said, "to financially incentivize these competitors to get there when we need them to get there."

Perna, whose confirmation appears likely, did not push back.

"I fully agree with you, senator," he said, without elaborating on what such a prize should be.

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