The only way to fight back against conspiracy theories involving the experimental COVID-19 vaccines, the politicization of the development and regulatory processes and the hesitancy to use those products once available is to earn the public's trust by being fully transparent, the head of the U.S. National Institutes of Health said.

People must be able to have the facts, NIH Director Francis Collins told senators Sept. 9 on Capitol Hill.

"Our best antidote is to say exactly what we're doing," Collins said at the Senate Health, Education, Labor and Pensions Committee hearing.

The NIH chief's testimony came as concern from Capitol Hill and the American public continues to mount about whether the Trump administration is trying to rush a vaccine through the development and regulatory processes.

President Donald Trump has openly and repeatedly exerted political pressure on the U.S. Food and Drug Administration to approve a COVID-19 vaccine by the Nov. 3 election.

White House Chief of Staff Mark Meadows said Aug. 23 that the administration was willing to put "heat" on regulators if they "don't see the light."

A number of senators at the hearing, including Sens. Patty Murray, D-Wash., the committee's ranking member, and Elizabeth Warren, D-Mass., noted that Trump has made the unsubstantiated claim that FDA scientists are "deep state" operatives.

Trump has also tied the success and speed of the COVID-19 vaccine development process to his reelection campaign, they said.

Collins told lawmakers it should be reassuring to Americans that there are a number of steps involving scientific objectivity in how the COVID-19 vaccines will be evaluated.

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None of the results from the ongoing phase 3 trials will go before the FDA for review until the studies' data and safety monitoring boards, or DSMBs, look at the data first and make their determinations, he said.

"Only when they say something's happening here that looks like it might be actually worth reviewing does this get brought forward," Collins said.

DSMBs are not federal employees but are "very experienced qualified scientists," he noted.

Collins again pushed back against Trump's claim there could be a vaccine by Nov. 3, saying there is no way to know that outcome right now.

Industry pledge

Collins praised the nine CEOs from companies involved in COVID-19 vaccine development who pledged Sept. 8 in a joint statement to not seek emergency use authorization, or EUA, or licensure from the FDA until those products have demonstrated safety and efficacy through phase 3 clinical testing designed and conducted to meet the regulatory requirements.

"We're going to have to work really hard, though, in the coming weeks or months to get the facts out there about how the decisions are going to get made," the NIH chief acknowledged, adding the information will need to be put forward in a way that is "digestible" to all Americans.

But Rachel Sachs, associate professor of law at Washington University in St. Louis, said the biopharmaceutical companies' statement was weak on the commitments to data transparency and standards for marketing.

"It's disappointing to see zero mention of data transparency in the pledge," Sachs tweeted. "Precisely because there are concerns around the public's trust of the federal [government's] decisions, it's important for vaccine sponsors to ensure they are transparent about the data themselves."

The pledge also lacked clarity on whether the companies would only seek to market their vaccines in the U.S. on meeting the FDA's 50% efficacy requirement or the lower, much less rigorous EUA standards.

"In part because the federal government either can't or won't make specific commitments in these areas, there was room for industry to make those commitments and help the public see these as important events to watch for," Sachs said.

But, she said, the vaccine companies' statement "does not succeed on those fronts."

AstraZeneca hold

Collins' remarks urging biopharmaceutical-makers to be transparent came hours after AstraZeneca PLC revealed it had put a phase 3 trial of its experimental COVID-19 vaccine on hold after a participant experienced a serious adverse event.

The company did not disclose the type of event in its Sept. 9 statement.

But Stat News reported Sept. 9 that AstraZeneca told investors in a conference call that while no diagnosis had been made, the study participant had neurological symptoms consistent with transverse myelitis, an inflammation of the spinal cord — information the company did not disclose to the public. The DSMB confirmed the trial participant received the experimental vaccine and not a placebo, investors on the call told Stat.

AstraZeneca later issued a follow-up statement reiterating no final diagnosis has been made, and "there will not be one until more tests are carried out."

The company confirmed news reports it was the second time AstraZeneca had paused its trial — information it had not previously disclosed to the public. The study participant involved in the July study pause was later confirmed to have previously undiagnosed multiple sclerosis.

Collins noted that it is "not at all unprecedented" to put a study on hold after there has been a single serious adverse event in a large clinical trial.

"You always have to try to figure out is that because of the vaccine or were they going to get that illness anyway," the NIH director told the senators.

Collins said he did not have any other information about the latest adverse event in AstraZeneca's trial beyond what he had read in the news but said the fact the study was paused "should be reassuring to everybody when we say we are going to focus first on safety and make no compromises."