Katalin Karikó, now a vicepresident at BioNTech, and her colleague Drew Weissman of the University of Pennsylvania, received this year’s Nobel Prize for Physiology or Medicine for work on messenger RNA, or mRNA. Announced Monday, the Nobel Foundation said their work was “critical” to the rapid development of the first vaccines against the coronavirus in 2020.

Karikó started studying mRNA, a “translator” that turns the instructions of DNA—which makes up humans’ genetic code—into proteins cells produce to make the body run. “I always thought that the majority of patients don’t actually need new genes, they need something temporary like a drug, to cure their aches and pains,” she told Wired in 2020. 

The rejections started soon after Karikó received her PhD in 1982, set on leaving her native Hungary. After several European labs told her there was no room for her, Karikó, her husband, and their two-year-old daughter snuck out of communist Hungary in 1985, smuggling 900 pounds sewn into their daughter’s teddy bear. Karikó took a job at Philadelphia’s Temple University, but four years in, she reportedly argued with her boss and was ejected from the university, risking deportation. Continuing her research at the neighboring University of Pennsylvania, Karikó ran into defeat after defeat—her cells kept dying after receiving injections of modified mRNA and she couldn’t figure out why. 

By 1995, her UPenn bosses gave Karikó an ultimatum: Give up her research or face a demotion and a pay cut. Karikó received the directive while her husband was stuck in Hungary for six months over a visa issue and the same week she was diagnosed with cancer, she told Wired. 

It was “so horrible,” she told Stat News in 2020. “I thought of going somewhere else, or doing something else,” she said, adding, “I also thought maybe I’m not good enough, not smart enough.”

Her new role pushed her off the tenure track—a major goal for any academic career — and drove her pay below that of her lab tech, according to Wired. In 2013, she was pushed out of the Ivy League school for good, she told the Nobel Foundation’s Adam Smith, who heads science outreach at the organization, in an interview Monday.

“I was kicked out from Penn—I was forced to retire,” she said. 

In a statement, a UPenn spokesperson called Kariko and Weissman “outstanding scientists” and called their Nobel “deeply deserved.”

“We acknowledge and are grateful for the valuable contributions Dr. Kariko has made to science and to Penn throughout her time with the University, including as a research assistant professor in the division of Infectious Diseases, as a senior research investigator in the department of Neurosurgery, and now as an adjunct professor in the department of Neurosurgery,” spokesperson Ron Ozio said in an email.

‘I was not even a professor‘

What kept Karikó going, she told Smith, was collaborating with Weissman—a UPenn professor she met by chance during a tussle over a photocopy machine. Her husband’s support during the nine years she “commuted to Germany” to her job at BioNTech, was also fundamental, she said. 

Karikó, at 58, “did all these experiments with my own hands…I was still culturing plasmids and feeding cells,” she told Smith. Her late mother regularly suggested Kurikó should get the Nobel, the scientist would laugh, saying, “I was not even a professor, [with] no team.”

The breakthrough finally came in 2005, when Kurikó and Weiddman published research demonstrating how to modify mRNA in a way that would not trigger cell death, making the technology usable for vaccines and other types of therapies.

This marked a ”‘paradigm change,” the Nobel Foundation wrote, praising Karikó for staying “true to her vision of realizing mRNA as a therapeutic despite encountering difficulties in convincing research funders of the significance of her project.” (Penn still holds the patent to the duo’s research, local station WHYY reported.)

The experience points to an age-old lesson, Smith said, “The message of all this is that persistence can pay off in the end.” And the scientist agreed: “You persevere,” she said.