Katalin Kariko: Scientist

Katalin “Kati” Kariko, born on January 17, 1955 in Hungary, is an American biochemist whose research into mRNA (messenger ribonucleic acid) is the foundation of COVID-19 vaccines.  

The woman who would one day be called a hero of the COVID pandemic, grew up in a two-room house in a small village about two hours east of Budapest, Hungary.  Her father was a butcher and her mother, a bookkeeper. A year after she was born, the failed Hungarian revolution made life even more difficult under Communist rule. The family had no running water, no refrigerator and a primitive stove. They grew their own vegetables and raised pigs. There was a neighbor who had a cow. Nearby were forests and woods to explore. This was Kariko’s childhood world and it nurtured a life-long love for science. It was a subject she excelled in as a student, and by eighth grade, she was ranked number three in the country in biology.

From an early age, Kariko knew she wanted to be a scientist. But it was at the University of Szeged, Hungary, where she got her Ph.D and did post-doctoral work, that she zeroed in on the new field of mRNA. She was fascinated by this tiny molecule that carried the genetic script to the body’s cells to make protein, enzymes and other molecules that are the basis of human life.  Kariko believed mRNA could be programmed to tell cells to make its own treatments to fight flu, cancer, stroke and other serious diseases. It was an exciting idea but one not easy to prove and also considered more than a little off-beat in the conservative scientific community. 

In 1985, when funding ran out at the Hungarian university, Kariko had already spent several years working on mRNA.  There was still so much more to investigate, and she refused to give up.  When Temple University in Philadelphia offered her a position in a post-doctoral program, Kariko happily accepted. She and her husband bought one-way tickets and sold the family car. Officially, it was illegal to leave the country with more than $100, but in the days before airports had X-ray screening, she smuggled the proceeds (about $1,200 in today’s dollars) by sewing it inside her daughter’s teddy bear.  Years later, the bear sits in her daughter’s old bedroom in Kariko’s home. 

Over the next two decades, against huge odds, Kariko never lost sight of her belief in the transformative power of mRNA.  The more obstacles she faced, the more she was driven to prove her beliefs.  She worked weekends and evenings on her own time despite being dismissed, overlooked and rejected by grantors and the scientific community.   At one point in her career, her husband calculated that with the extra hours she put in, her salary amounted to one dollar an hour. 

By 1989, Kariko was a researcher and assistant professor at the University of Pennsylvania’s Medical School. It wasn’t a prestigious teaching job on the tenure track, but rather a position that needed to be supported by grants, which were tough to win for mRNA.  It had been nearly thirty years since mRNA first had been identified, however government and private companies were still not convinced about its potential for therapies and medicines.

There was also a lot of skepticism among the scientific community at Penn. Things changed in 1997 when Drew Weissman, an immunologist who had just finished a fellowship at the National Institutes of Health, joined the Penn Medical School.  He wanted to develop a vaccine against HIV and was intrigued by the idea that mRNA could be the key to develop a new kind of vaccine. Traditional vaccines like flu or measles inject a dead version of the virus into a person to spur the immune system to build up antibodies.  A vaccine that did not contain a live or dead piece of the virus it was trying to fight would be revolutionary and lifesaving, bypassing the years of trials required by traditional vaccines. 

In the lab, Weissman and Kariko’s initial experiments failed when the mRNA they created triggered an inflammatory response in the cells. That inflammation would kill the already fragile mRNA, stopping their experiments cold.  They spent several years trying to figure out why. The breakthrough came after they modified one of the chemical strands in mRNA structure and encased the molecule in a fatty compound. With these changes, they were on their way. By 2005 they were able to show that the mRNA vaccines they tested had been nearly 100% effective in protecting lab animals from getting infected and sick from more than 20 diseases, including flu, HIV, hepatitis and norovirus. 

Kariko and Weissman filed patents and published their findings in scientific journals. But instead of a flood of congratulations, there was little reaction. Fifteen years before the outbreak of COVID-19, the world was not ready for their breakthrough research. 

In 2013 Kariko retired from Penn and went to BioNTech, a pharmaceutical company, to work on developing a mRNA vaccine for cancer. When COVID broke in January 2020, BioNTech was able to design a vaccine within hours. Researchers at Moderna where another team was working on its own mRNA vaccines, created their vaccine in two days.  Twelve months later in December of 2020, after the first trials proved the vaccine’s effectiveness, Kariko and Weissman were among the first to get vaccinated at the University of Pennsylvania. 

While there were other scientists who worked on developing the vaccines, it was the four-decade vision of Kati Kariko that paved the way. She persisted and her determination not only saved millions of lives but pioneered a new way of developing vaccines for serious disease. 

She and Weissman have received numerous awards from around the world since 2021, including the prestigious Vilcek Prize for Excellence in Biochemistry (2022) and the Lasker DeBakey Clinical Medical Research Award (2021).

©2023 Alice Look
Co-founder, Remarkable Women Project.org
Executive Producer, Remarkable Women Project