White House officials will likely object to new, stricter COVID-19 vaccine guidelines proposed by the FDA two weeks ago.
According to the New York Times, the proposed guidelines were 'stalled' by the office of White House Chief of Staff Mark Meadows.
Trump had previously suggested the White House could block the requirements.
He is angling for a COVID-19 shot to get approved by Election Day.
Scientists and the public have expressed concern that vaccine development is moving too fast and a shot would not be safe.
Requirements allegedly in the new rules could make it nearly impossible for a vaccine to get approved before the November 3 election.
White House officials take issue with a proposed rule that would require vaccine developers to follow trial participants for two months after their second doses.
That would make it next to impossible for the shots to get approval.
The Trump administration will block the approval of stricter coronavirus vaccine approval guidelines proposed two weeks ago by the Food and Drug Administration (FDA), according to the New York Times.
Regulators had hoped to raise the standards for vaccine makers as the number of Americans who said they would trust the safety of a shot developed under the White House's vaccine initiative, Operation Warp Speed.
President Trump, who is now battling coronavirus himself, has continually hinted that a vaccine could be available by Election Day, on November 3, raising concern that the FDA and vaccine makers might bow to political pressure rather than prioritize shot safety.
After the Washington Post reported the possible rule change last month, President Trump said that his administration could block proposed changes to standards.
Since being submitted for approval by the Office of Management, sources told the Times that the proposed changes have been 'stalled' by White House Chief of Staff Mark Meadows.
The proposed guidelines would require vaccine makers to follow trial participants for at least two months after their second does of a candidate shot before submitting data for FDA approval.
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Because Pfizer's and Moderna's late stage trials began in July, this would make it nearly impossible to meet this requirement before November 3.
Operation Warp Speed itself already has recommended the vaccine candidates it is supporting observe 'a two-months follow-up after completion of the immunization process before the company will consider filing for an emergency use authorization,' vaccine czar Moncef Slaoui said last month.
But the White House does not agree with the more protracted timeline, and at this point, the guidelines are unlikely to get approved, clearing a potential path for a shot to get approved by Election Day.
'The vaccines are coming momentarily,' Trump said Monday night in a video posted to his Twitter, upon his return to the White House from Walter Reed National Medical Center.
An advisory committee set to meet soon to agree upon standards for a vaccine could choose enact the proposed guidelines - but it would escalate already high tensions between regulators and the White House.
Concern is rising among public health experts and citizens that a vaccine could be rushed without proper safety checks, especially as the November presidential election nears.
Dr Leon McDougle, president of the National Medical Association, on the call raised concern that the White House might block new, stricter FDA recommendations.
President Donald Trump said last month he may or may not approve any new, more stringent FDA standards for an EUA of a COVID-19 vaccine.
Trump has repeatedly said a vaccine for COVID-19, the disease caused by the coronavirus, could be ready for distribution ahead of the election.
'We completely agree with it,' Dr Slaoui said, referring to the stricter FDA regulations during a virtual Town Hall event on last month organized by the Rainbow Push Coalition in Atlanta.
According to a Pew Research Center survey earlier this month, only 32 percent of Black adults said they would definitely or probably get a COVID-19 vaccine, compared with 52 percent of White adults, 56 percent of Hispanics and 72 percent of Asian Americans.
CORONAVIRUS VACCINE APPROVED IN A MOVE THAT COULD BLOCK TRUMP'S PLAN TO HAVE A SHOT BY ELECTION DAY
The US Food and Drug Administration (FDA) is expected to issue new, tougher requirements for its approval of a coronavirus vaccine, a move that could obliterate the chances of a shot getting emergency use authorization before Election Day, according to the Washington Post.
Regulators could publish the new approval standards as early as this week, and will do so publicly in an effort to bolster Americans' eroded trust in the US to ensure the safety a COVID-19 vaccine.
President Trump and his Operation Warp Speed initiative have been pushing for months to have a coronavirus vaccine approved ahead of the November 3 election.
But according to a new Axios poll, less than 40 percent of Americans now say they would get a coronavirus vaccine, with most citing fears over its safety, driven by the Trump administration's concerted effort to expedite the development process.
Shoring up the standards for emergency use authorization (EUA) that allowed hydroxychloroquine to slip through to the market, the FDA will now require that companies making vaccines continue to follow trial participants for at least two months after they get a second dose of a shot (if one is required), an anonymous source told the Post.
That stipulation alone could easily push the timeline for submitting data for EUA back until after the election for both Pfizer and Moderna, which only began enrolling participants in their late-stage trials in late July.
A source close to the matter, but who asked to remain anonymous, said that the FDA plans to add a requirement that a vaccine trial's data will only be sufficiently complete for the agency to consider approval if at least five participants in the placebo group develop severe COVID-19.
That will be a key metric for the the efficacy of a vaccine against a virus that has not only spread like wildfire to nearly seven million people in the US and more than 31 million worldwide, but has killed more than 200,000 Americans.
And the death toll weight heaviest upon older people. The sources also told the Post that the FDA's updated guidance will require trials to include cases of coronavirus in older Americans.
Previously, the FDA's primary requirement to consider emergency use authorization for a COVID-19 vaccine was that it be at least 50 percent more effective at preventing infection than a placebo.
In the simplest sense, that means that there should be at least 50 percent fewer infections in the group that got the vaccine, compared to those who were given a placebo shot.
Vaccine trials require that participants go about their normal lives while scientists track how many catch the disease the shot is meant to protect them against - in this case, coronavirus.
Late-stage trials being run by Moderna and Pfizer initially aimed to recruit 30,000 participants each. Both companies decided earlier this month to expand their trials by about 50 percent, to 44,000 participants.
The two companies launched phase 3 testing on the same day, July 27. Pfizer currently has 29,481 participants enrolled while Moderna announced Friday that it has enrolled nearly 26,000 participants, of whom 11,879 have received both doses of vaccine.
It's not clear whether the FDA's new guidance will require the companies to have followed every participant for two months after vaccination in order to get emergency use authorization, or just a portion of the participants.
Moderna and Pfizer each reached the halfway mark for enrollment of their respective studies around the end of August. Still just under half of the participants in it is stud have received the second dose of Moderna's shot.
At that rate, it seems nearly impossible either company's shot could get approval before the election, although Moderna anticipates it will know whether its shot works by November, and Pfizer plans to announce its results in late-October.
FDA Commissioner Dr Stephen Hahn, has not addressed the possibility of new vaccine approval standards.
Trump himself handpicked Dr Hahn to ascend to the head of the FDA, over-stepping presumptive commissioner Ned Sharpless.
Dr Hahn, plucked from his position as an executive at Texas's renowned MD Anderson Cancer Center, has since found himself caught between politicians and scientists with regularity.
He's been in Trump's crosshairs after refusing to endorse the president's claims that most coronavirus case are 'harmless,' while drawing the ire of scientists after his agency gave emergency approval to the use of coronavirus survivors' plasma to treat those who were still sick, against the National Institutes of Health's advice.
After that controversial approval, Dr Hahn inaccurately pulled the statistic that plasma saved more than a third of people treated with it from an unpublished, poorly-designed study and had to apologize.