Two scientists who met at a copy machine and worked for decades in obscurity were awarded the 2023 Nobel Prize in Physiology or Medicine on Monday for research that led to the mRNA COVID-19 vaccines.

More than 600 million mRNA vaccines had been delivered to Americans as of early May to protect against severe COVID-19, and the technology is now being explored to treat other infectious diseases, cancer, genetic diseases, heart disease, allergies and autoimmune diseases.

The prestigious award was given Monday to Katalin Karikó and Dr. Drew Weissman, who met in 1997 at a hallway copy machine at the University of Pennsylvania. Karikó, an assistant professor and biochemist, was investigating messenger RNA technology and Weissman, an immunologist, had recently joined Penn from the National Institutes of Health.

They spent the next 20-plus years collaborating, "figuring out how to get it to work, how to get a vaccine to function well," Weissman, still a professor at Penn, said in a Monday news conference.

During all that time, they struggled to get funding or even to publish their findings. "We couldn't get people to notice RNA as something interesting," he said.

They kept pursuing the research, he and Karikó said, because they saw its potential, even if others didn't.

In 2015, Karikó was forced to retire from Penn, though she remains an adjunct professor. Three years later, with support from her husband, she joined the German company BioNTech, which was then exploring commercializing mRNA technology.

Karikó, who was born in Hungary, commuted between the Philadelphia suburbs and Mainz, Germany, for more than a decade, conducting her own hands-on research decades after most scientists of her caliber would have passed such work to younger researchers.

BioNTech, where Karikó is now a consultant, partnered with Pfizer to develop one of the two mRNA COVID-19 vaccines that became available in the United States in December 2020.

Although the world may only have become aware of mRNA in 2020, it was not new science at the time, Karikó and Weissman said.

"We had three clinical trials going on before COVID hit," Weissman said. Thanks to the attention and credibility gained from the COVID-19 vaccines, there are more than 250 research trials now underway using mRNA technology, Karikó added.

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How they heard the news

Karikó's husband was awakened at 3:40 a.m. Monday morning by a phone call. "It's for you," he said, passing her the phone.

Thomas who said he was calling from Sweden told her she had just won the Nobel and by the way, did she have Drew's phone number, because the number he had didn't work.

She thought he was joking, but was a little reassured by how much scientific knowledge he seemed to have, so she provided him Weissman's cell number. A few minutes later, she texted Weissman. "Did Thomas call?"

"No. Who's Thomas?" he replied.

"Nobel Prize," she responded.

In a pre-dawn call, the two discussed whether they could really believe the news, or if it was an anti-vaxxer pulling a prank.

Usually, the Nobel committee waits an average of 9 years to award a scientific discovery, but it had been only three.

The pair decided to wait another hour for the live press conference in Sweden to announce the winner.

Weissman said he sat in bed with his wife and his cat, who was begging for food, until they knew the award was real. "Then we really became excited."

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What is the Nobel Prize?

The Nobel Prize is awarded by the Swedish Nobel Foundation, and is a set of awards given annually to people in physics, chemistry, physiology or medicine, literature and peace. There is also a prize given in Economic Science, funded by the Sveriges Risbank in 1968.

The first award was given in 1901.

It was created by Swedish industrialist Alfred Nobel, known for his invention of dynamite, in his will in 1895.

There have been 114 medicine prizes since the Nobel Assembly at Nobel Assembly at Karolinska Institutet began to award the Nobel Prize for Physiology or Medicine. There have been 227 medicine laureates, with 13 women among those awarded.

In a press release, the Nobel Assembly at Karolinska Institutet called Karikó and Weissman's work "critical for developing effective mRNA vaccines." 

In a 2005 paper, the pair showed they could modify mRNA to stabilize it and reduce an unwanted inflammatory reaction. "This was a paradigm change in our understanding of how cells recognize and respond to different forms of mRNA," according to a Nobel summary of their work. "Karikó and Weissman immediately understood that their discovery had profound significance for using mRNA as therapy."

In an interview Monday with a Nobel representative, Karikó said her mother, who died in 2018, would listen to the Nobel announcements every year, hoping her scientist daughter would be among the winners.

"I was not even a professor," Karikó said, patiently explaining to her mother that it wouldn't be possible for someone of her standing to be considered for the award, no matter how hard she worked.

On choosing science

Both Karikó and Weissman said they hope the attention from the Nobels inspire more young people to go into the sciences.

"If you like the spotlight, you should be an actor or an actress. If you like to follow instructions, join the military," Karikó said. "If you like to solve problems, science is for you."

Scientific research is necessary for society to move forward, Weissman said.

Failure is part of the process and just something to get used to, said Karikó, whose daughter Susan is a two-time Olympic rowing champion. But she and Weissman also took pleasure in their collaboration, their research and its impact.

"It's not coming easily, but it is fun and we do it with great happiness," she said.

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