A group of biopharmaceutical companies pursuing experimental COVID-19 vaccines are following Merck & Co. Inc. Chairman and CEO Kenneth Frazier's lead in pledging they will not seek U.S. approval of their products unless there are substantial data to support emergency use authorization or licensure.

"We believe this pledge will help ensure public confidence in the rigorous scientific and regulatory process by which COVID-19 vaccines are evaluated and may ultimately be approved," the companies said in the statement published Sept. 8.

Among the vaccine makers which signed the statement are Johnson & Johnson, Moderna Inc. and Pfizer Inc.

If a COVID-19 vaccine is approved in 2020, 65% of U.S. voters surveyed believe it would be rushed without enough testing and 58% said they would wait to get the shot, while 21% said they would never get it, according to a Sept. 6 CBS News poll.

Frazier had publicly urged companies during a Sept. 3 online briefing hosted by the International Federation of Pharmaceutical Manufacturers and Associations to commit to not sacrificing safety under any set of circumstances, despite the urgency of the COVID-19 pandemic.

"The issue of vaccine confidence is a critical one," he said.

Vaccine makers have a lot to lose if there is even a perception that their COVID-19 vaccines are not safe or effective, despite an FDA approval, tweeted Jason Schwartz, assistant professor of health policy and the history of medicine at Yale University. A hit in public confidence would also be bad for biopharmaceutical companies with large routine vaccine businesses, he said.

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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.

Trump told reporters Sept. 4 that "We think we can probably have it sometime during the month of October."

On Sept. 7, Trump again insisted that a COVID-19 vaccine would be approved "very soon" by the FDA, "maybe even before a special date — you know what date I'm talking about." He said he had talked with executives from Pfizer and J&J.

Neither Trump nor the White House have access to the data in the ongoing phase 3 trials testing the experimental COVID-19 vaccines. Only the clinical trials' data and safety monitoring boards have such access.

In a Sept. 3 open letter, leaders from the Biotechnology Innovation Organization called on the FDA to maintain its "historic independence as the gold-standard international regulatory body, free from external influence."

Both U.S. National Institutes of Health Director Francis Collins and National Institute of Allergy and Infectious Diseases Director Anthony Fauci have repeatedly said it was highly unlikely data from phase 3 trials would be ready for the FDA's review in October.

Former Vice President and Democratic presidential nominee Joe Biden told reporters Sept. 7 he trusted Fauci and other U.S. public health experts and scientists on COVID-19 vaccines but said Trump has been "playing politics" and "undermining public confidence." Biden's running mate, Sen. Kamala Harris, D-Calif., made similar remarks Sept. 6 on CNN.

Former FDA Commissioner Scott Gottlieb, a venture capitalist who is on Pfizer's board, told CBS' "Face the Nation" Sept. 6 that he doubted U.S. government scientists who will make the regulatory decisions on COVID-19 vaccines will stand for being "pushed around."

Moncef Slaoui, chief scientific adviser for the White House's Operation Warp Speed project, and Peter Marks, director of the FDA's Center for Biologics Evaluation and Research, both said they would resign if the White House interfered with the approval process for any COVID-19 vaccines.

No sign of Trump's health plan, orders

Americans continue to wait for Trump's healthcare plan, which he vowed would be unveiled by the end of August — a promise he has repeatedly failed to keep since his 2016 run for the White House.

Trump said he would also copy the Affordable Care Act's preexisting conditions protections into an executive order before the end of August — another pledge he did not keep.

In addition, the White House has remained silent on the text of Trump's July 24 order to require drugmakers to offer the U.S. government the lowest prices paid by other developed nations for prescription medicines. The text of the favored nations order was due to be revealed Aug. 25.

Executive orders cannot change or replace existing U.S. laws, have limited authority, can be difficult to enforce without legislation, take months, if not years, to implement and can easily be challenged in court.

One of Trump's July 24 drug pricing executive orders is now under review at the White House Office of Management and Budget, according to a Sept. 1 notice.

The order instructs federally funded community health centers, or FQHCs, to pass on discounts for insulin and emergency anaphylaxis medicines to Americans with low incomes.

But overall, the order may not dramatically help very many people — short of an extremely generous definition of low income — and may create a burdensome new requirement for FQHCs, tweeted Karyn Schwartz, a senior fellow at nonpartisan, nonprofit Kaiser Family Foundation.