"I know there are a lot of public voices talking about when vaccines will be ready, but the fact of the matter is you can't rush science," Frazier said on CNBC's "Fast Money: Halftime Report."
Frazier's comments come one day after Merck and other leading vaccine developers, from both the U.S. and the U.K., issued a pledge to make safety the top priority as they seek regulatory approval. And later Tuesday, AstraZeneca, another signatory of the letter, said it was putting its late-stage vaccine trial on hold due to safety concerns, with one participant in the U.K. having a possible serious adverse reaction. The company called it a "routine action" that "has to happen whenever there is a potentially unexplained illness in one of the trials."
The development of a Covid-19 vaccine is being intensely watched as the pandemic persists across the world. There are at least 27.6 million confirmed cases of the coronavirus worldwide, according to data compiled by Johns Hopkins University. At least 899,318 people have died.
In the U.S., where there at least 190,000 deaths linked to Covid-19, there has been growing concern about political considerations influencing the vaccine approval process.
President Donald Trump has established an effort to speed up coronavirus vaccine development in the U.S. called Operation Warp Speed, which has the goal of providing at least 300 million doses by January 2021. Trump has also suggested it is possible a vaccine could be approved, at least in some capacity, before Nov. 3 — the day of the presidential election.
Frazier earlier this summer said raising expectations that a vaccine could be ready by the end of 2020 was doing "grave disservice to the public." On Wednesday, Frazier emphasized the need for clinical trials to proceed and referred to the letter issued by fellow drugmakers.
"We have to be very careful and deliberate. ... We're pledging, as the sponsors, as the developers, that we're actually going to be that careful. We're going to be that deliberate coming forward with these medicines because we know we're going into healthy people and when you're putting these vaccines into healthy people, you have to do everything possible to ensure that these vaccines are both safe and effective," Frazier said.
Frazier's appearance Wednesday on CNBC came as part of a special "Fast Money: Halftime Report," focusing on increasing diversity in leadership and roles of influence at U.S. companies. One of the focuses of the show was on the Board Challenge, which was announced Wednesday. Founded by Altimeter Capital, Valence and theBoardlist, the initiative seeks to accelerate action to improve the representation of Black leaders in the boardrooms of corporate America.
Frazier, one of four Fortune 100 Black CEOs, said an important action taken by Merck to increase its board diversity was to expand the pool of qualified candidates. Secondly, he said the company worked to combat systemic and implicit barriers to "getting the best talent."
He emphasized the role of people's own social networks in hiring for senior management roles and board positions. "As long as we don't have African Americans and Latinos represented at the highest echelons of corporate America, both in management and also in the boardroom, it's unlikely that African Americans and Latinos who are coming through the system will be able to take advantage of those social networks," he contended.
Frazier, a member of Exxon Mobil's board, said he's speaking from experience and referenced conversations he's taken part of in the past. "I know that we want to find a pool of qualified people, but often we ask the kinds of questions like, 'does anybody know this candidate?' and, 'do you think this candidate would be a good fit?' So those kind of relationship issues are critical. They become the networking issues that either include people or unintentionally exclude people."
As the U.S. continues to experience demonstrations around racial injustice, sparked in May by the death of George Floyd in Minneapolis, Frazier said he cannot say for sure whether there will be meaningful reforms that create long-lasting change.
"But I have to say, this time feels different in that the conversation is happening in every boardroom and it's happening around kitchen tables all in America around a really difficult issue, around the systemic effects of racism," he said.
Referencing differences between Black and White Americans in wealth and health outcomes, Frazier said, "it's not logical to say that none of those disparities in outcomes link back to disparities in opportunity."