No Evidence Pfizer Conducting Any Inappropriate Coronavirus Experiments


SciCheck Digest

Scientists say the experiments Pfizer has performed on the coronavirus are standard for the industry. Baseless claims that the company is mutating the virus for profit, however, have been circulating since the release of a popular undercover video from the conservative activist group Project Veritas.

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An undercover video from the conservative activist group Project Veritas has spawned baseless claims that Pfizer is mutating the coronavirus in an elaborate plot to sell more vaccines. There is no evidence of such a conspiracy, and the company denied those claims in a statement.

People online are now citing a sentence in the statement about certain experiments Pfizer is doing for its COVID-19 antiviral drug Paxlovid to misleadingly claim that the company has “admitted” to performing gain-of-function research. 

As we’ll explain, there is debate about whether the described experiments can be considered gain-of-function, a nebulous term that has become politically charged since some Republicans and others have alleged, without credible evidence, that the coronavirus originated from such an experiment in China. There’s no evidence, however, that Pfizer has done any improper research, nor is there any indication of a nefarious plot to increase sales of COVID-19 vaccines.

Undercover Video and Pfizer Response

The brouhaha about Pfizer began when Project Veritas, which is known for its controversial and sometimes misleadingly edited “sting” videos, released an undercover video featuring a person identified as a Pfizer executive named Jordon Trishton Walker on Jan. 25.

Walker, who is described in the video as a “Director of Research and Development, Strategic Operations and mRNA Scientific Planning,” says that Pfizer is “exploring” mutating the coronavirus, or SARS-CoV-2, to “preemptively develop new vaccines.” He then describes a theoretical experiment infecting monkeys as a way to get a mutated virus.

In another snippet of the edited video, the undercover operative asks if the experiments are gain-of-function. Walker says they aren’t, and refers to “directed evolution,” which he says is “very different.”

The video went viral, with more than 30 million views on Twitter alone by Feb. 7, according to the social media company’s public metrics.

Two days after the video appeared, Pfizer responded, saying in a statement that it “would like to set the record straight” and that “Pfizer has not conducted gain of function or directed evolution research” for its COVID-19 vaccine.

A creative rendition of SARS-CoV-2 virus particles (not to scale). Photo by NIAID.

Pfizer, however, added that as part of the research required by the Food and Drug Administration and other regulators for its oral antiviral COVID-19 treatment, the company does “in vitro work (e.g., in a laboratory culture dish) to identify potential resistance mutations to nirmatrelvir,” referring to the primary component of Paxlovid.

“With a naturally evolving virus, it is important to routinely assess the activity of an antiviral,” the statement continued. “Most of this work is conducted using computer simulations or mutations of the main protease–a non-infectious part of the virus. In a limited number of cases when a full virus does not contain any known gain of function mutations, such virus may be engineered to enable the assessment of antiviral activity in cells.”

“In addition, in vitro resistance selection experiments are undertaken in cells incubated with SARS-CoV-2 and nirmatrelvir in our secure Biosafety level 3 (BSL3) laboratory to assess whether the main protease can mutate to yield resistant strains of the virus,” Pfizer added, once again emphasizing that the research is required by regulators and performed by many labs.

The statement was incorrectly interpreted as an admission that Pfizer was performing risky experiments it should not have been doing — and in some cases taken as proof of the alleged conspiracy described in the Project Veritas video.

Quoting the “limited number of cases” sentence from the Pfizer statement, Dr. Robert Malone, a known purveyor of misinformation about the COVID-19 vaccines, wrote on Twitter, “= ‘we plead guilty as charged, your honor.’”

“Don’t forget Pfizer just admitted to using gain of function to create bio weapons,” another Twitter user wrote in a Feb. 4 tweet.

Fox News host Tucker Carlson also misleadingly said in a segment on his show, which was excerpted and shared by conservative commentator Dan Bongino on Facebook, that the Project Veritas video “contained no misinformation” and with its statement, “Pfizer admitted that.” 

‘Bumbling Nonsense’

Multiple scientists told us that Walker appeared uninformed, and the experiments he described as having been discussed — but not performed — would make little sense for Pfizer to do.

Tyler Starr, an assistant professor of biochemistry at the University of Utah who studies protein evolution in viruses, including SARS-CoV-2, called Walker’s comments “bumbling nonsense.” 

“I think it’s clear from his position title, his training, and how he talks that he is not that close to the experiments himself, and I take very little stock into what he says about how and what experiments are being considered and why,” he said in an email (emphasis is his).

“Sure, it’s a possible experiment to passage the virus through vaccinated primates to see what might happen, but this experiment would be very expensive (and potentially risky),” he said. “Primates wouldn’t capture the broader aspects of human transmission very effectively anyway, so there’s no real purpose to doing that experiment.”

Dr. Stanley Perlman, a coronavirus researcher at the University of Iowa and member of the FDA’s vaccine advisory committee, agreed. “You’d hardly have to do it in an experimental animal, you’d just find it in people,” he said of vaccine resistance. “It wouldn’t be a terribly useful thing for a drug company to do.”

“Nobody passages virus in monkeys repeatedly. I am not aware of how useful this will be especially without drug pressure (treatment),” Dr. Raymond F. Schinazi, a biochemist at Emory University School of Medicine who designs and develops new antivirals, told us in an email. He questioned whether Walker had any experience in virology or real insight into what Pfizer is doing.

Starr said it seemed plausible that Walker might have been describing discussions that actually occurred, “[b]ut could either be between a bunch of other executives with little virological training like himself as just a ‘brainstorm anything in the world’ type of discussion, far removed from anything practical that would be done.”

“It really reads to me like somebody who was in a conversation that they were only technically astute enough to understand about 25% of, which is the exact danger zone for maximal impact of ignorance!” he added.

Thomas Gallagher, a professor of microbiology and immunology at Loyola University Chicago who studies coronaviruses, similarly said he didn’t find Walker to be “a credible spokesperson for Pfizer’s virology research.”

We attempted to contact Walker, but were unsuccessful. Pfizer did not respond to our inquiries asking about him.

But as we wrote in a story about another undercover Project Veritas video featuring Walker, a man with his name appears to have graduated from UT Southwestern Medical School in 2018. He went on to intern at Tufts Medical Center for one year in general surgery and then was employed by Boston Consulting Group from January 2020 until June 2021. This suggests Walker has limited if any virology experience.

In yet another Project Veritas video, in which the group revealed itself to Walker, he said as much.

“I’m not even a scientist by background … I came from a consulting firm that does business,” Walker said. “This is absurd.”

The video, which was released on Jan. 26 — but promoted far less than either undercover one — shows Walker getting upset, calling the police and at one point taking and then smashing on the floor an iPad Project Veritas was using to show him the secretly recorded video.

“I was trying to impress a date. By lying,” he said during the confrontation. “Why are you doing this to someone who’s just working at a company to literally help the public?”

Antiviral Experiments

The second main claim related to the Project Veritas video stems from the statement Pfizer released in response to the video, although the company did not name the group.

Pfizer denied having done any “gain of function or directed evolution research” for its COVID-19 vaccines. But some sentences describing work for its antiviral, Paxlovid, were interpreted as an admission that the company had done gain-of-function research, with some people baselessly suggesting that this was somehow evidence that Pfizer was indeed mutating viruses to intentionally unleash them on the public to sell more vaccines.

Experts told us the described experiments are standard. Some of these might be considered gain-of-function, but that depends on someone’s definition of the term. And even if they are, that doesn’t mean that Pfizer shouldn’t have been doing them.

As Pfizer noted, its experiments were required by the FDA and other regulators. The company pointed us to the FDA’s emergency use authorization letter for Paxlovid and two other industry guidance documents, which describe the types of experiments antiviral drugmakers are expected to do. Perlman said he agreed with the company’s interpretation.

“Antiviral drugs have to be evaluated for their potential to generate antiviral drug-resistant mutants. The standard methods are to propagate viruses in the presence of the antiviral drug and then identify potential resistant mutants by sequencing,” Gallagher said.  

“If there are several mutations that arise in response to the selective pressures of the antiviral drug, then one must know which of the mutations are conferring the drug resistance, and which are not. To find out, viruses are often engineered to contain only one (or a subset) of the mutations, with the engineered viruses then tested for resistance to the antiviral drug,” he continued, adding that such tests “are standard and appropriate tests in antiviral drug development.”

The gain-of-function debate is partly a semantic one. As we’ve written, gain-of-function is a broad term that could describe many entirely innocuous virology experiments in which a virus gains a new function. But the type that is controversial is the small subset of potentially risky experiments that give pathogens new functions that could be harmful if released from a lab. Typically, this has meant experiments in which there is a reasonable expectation to make a pathogen either more transmissible or virulent to humans.

Under that traditional definition, Gallagher said that the experiments Pfizer describes would not be classified as gain-of-function. “There is nothing in the Pfizer statement that says anything about any such gain of transmissibility or gain of virulence function experiments,” he said.

Perlman also said that gaining antiviral resistance is not necessarily the same as a gain-of-function. 

“If I take a bacteria that is sensitive to penicillin and now I make it resistant to penicillin by doing some sort of selection, but at the same time the bacteria can no longer grow in people, is that a gain of function?” he asked, in an analogy with bacteria. “I would consider that a loss of function.”

Schinazi, however, said that Pfizer’s experiments with Paxlovid did sound like gain-of-function research. And Starr said that the larger concern is that regardless of what it is called, some experiments have risks worth weighing against their benefits. And in theory, a virus resistant to certain drugs could be harmful if it accidentally escaped.

But that doesn’t mean that Pfizer has done anything improper. As we said, the experiments are standard for the industry to do.

Many labs, Schinazi said, “as well as industry conducts such in vitro studies (cell based) to learn more about the mutants and to determine if their new drug or analogs are going to be effective.”

If Pfizer did not use National Institutes of Health funding, then it would not be subject to federal review of its experiments under current regulations, he said, but the experiments would still be performed in a biosafety level 3, or BSL-3, lab after internal approval. BSL-3 labs require more training and protective gear and are equipped with specialized ventilation systems that prevent workers from being exposed to pathogens they might breathe in.

A federal advisory committee released draft guidelines on Jan. 20 that propose expanding the definition of gain-of-function research and removing some exemptions, but the changes have not yet been finalized or implemented.

“To me, it’s all kind of funny,” Perlman said of the concern about Pfizer’s experiments. “All of the mutations have arisen already if they’re going to arise. People get really worried, but the fact is that there’s so much drug use and so much virus around that it’s all going to occur naturally anyway,” he added, referring to Paxlovid.

Saranac Hale Spencer contributed to this story.

Editor’s note: SciCheck’s articles correcting health misinformation are made possible by a grant from the Robert Wood Johnson Foundation. The foundation has no control over’s editorial decisions, and the views expressed in our articles do not necessarily reflect the views of the foundation.


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