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Health Secretary Robert F Kennedy Jr. has long questioned the value of mRNA vaccine technology. And soon the Food and Drug Administration will decide whether to approve a new kind of flu shot built on mRNA.
How the agency rules on the experimental vaccine made by Moderna has big implications for the future of mRNA research.
In February, Moderna president Stephen Hoge was at one of the company's manufacturing sites, when the head of regulatory affairs, Charbel Haber, approached him.
Almost immediately Hoge knew something was wrong.
"Charbel came up to me and just had a very nervous look on his face," he says. "And when your head of regulatory comes up and has a concerned look on … [his] face, you take it seriously."
Moderna had just gotten a letter from the FDA. Hoge rushed with Haber to huddle with a few others in a nearby conference room.
"That's where you pop it up on a screen and it hits you, you know, right in the face," Hoge says.
The FDA said it would not review Moderna's application for its mRNA flu shot, effectively rejecting it.
It was a shock. "We had talked to the FDA at every step along the way, including prior to filing," he says. "And they had said, you can go forward and submit and we will conduct a review."
An FDA decision that reverberated
Moderna went public with what happened. The news shook the pharmaceutical industry. There was an outcry over the FDA's backtracking.
A little over a week later, the agency reconsidered and agreed to review the vaccine after Moderna promised to add a confirmatory study of the vaccine if it makes it to market. In June, a panel of advisers to the FDA recommended that the agency approve the vaccine.
The agency has a Wednesday deadline to make a decision. If the FDA gives it the green light, the Moderna vaccine would be the first mRNA-based flu shot to make it to market. But the FDA's flip-flop in February has already had a chilling effect.
Rena Conti, a health economist at Boston University, says the industry and its investors will be watching closely because the U.S. market is where they make most of their money. They depend on the FDA to be consistent and fair.
"They don't want to spend money if they don't think there's going to be a way to actually make money on the other end," she says.
What's more, the Department of Health and Human Services canceled nearly $500 million in mRNA vaccine research funding last summer.
In response to NPR's questions about the administration's actions on experimental mRNA vaccines, an HHS spokesman provided the following statement: "Under Secretary Kennedy's leadership, HHS is advancing President Trump's commitment to strengthen public health through gold-standard science, and FDA will continue applying rigorous, evidence-based standards to every product it reviews while supporting innovation that meets those standards."
Investors in mRNA research are wary
But Hoge says Moderna is holding off on some planned mRNA research until the company knows how things will shake out.
In the world of mRNA, Moderna is a big fish and most of the rest are tiny biotechs with 20 or 30 employees, says Jeff Coller, a professor at Johns Hopkins University who has studied mRNA technology for decades.
"When you see the FDA rejecting a product that comes from Moderna, why is it that my little company would be able to push through?" he says.
Coller says the FDA's actions combined with the HHS funding cuts spooked the venture capital firms that backed many of the smaller biotechs working on mRNA therapies for conditions ranging from Lyme disease to rare cancers.
That matters to people like 69-year-old Janusz Racz, a retired computer scientist who lives in London. When his doctors found inoperable Stage 3 lung cancer two years ago, it was a surprise.
He's a runner and sailor and had no symptoms, but the tumor was the size of a golf ball. If he did nothing, his doctors told him he would be dead in a matter of months.
Racz got into a clinical trial in London, where he lives, that made him the first person in the U.K. to receive an mRNA vaccine made by BioNTech, Pfizer's partner on the first vaccine against COVID-19.
"I decided just to participate because I saw that was a big chance." he says. "And also, as a scientist ... I wanted to participate in such a program to give other patients a hope."
After a year of regular vaccinations, the cancer is gone. He's making plans for the future while the study continues for other patients.
But he's watched as the Trump administration and Health Secretary Robert F. Kennedy Jr. have taken aim at mRNA vaccines.
Racz is a U.S. citizen, so he says he wrote Kennedy a letter.
"I told him my story," he says. "And this is a new hope for people, for millions of people. And they cut off the hope."
He says Kennedy never wrote back.
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