Biochemist Katalin Karikó

COVID-19 mRNA Vaccines

Katalin (“Kati”) Karikó is a Hungarian biochemist who devoted four decades to research messenger RNA (mRNA), a naturally occurring molecule necessary for protein synthesis. Dr. Karikó had a massive breakthrough when she discovered that nucleoside-modification of mRNA was required in order for the technology to work. Her research laid the foundation for the highly effective COVID-19 mRNA vaccines developed by Pfizer-BioNTech and Moderna.

Dr. Karikó’s scientific career has been a long, winding journey filled with glimpses of success riddled with considerable setbacks. As a child in rural Hungary, Kati was always curious about the natural world around her and early on decided to become a scientist even though she had never met one. She became fascinated by mRNA as a doctoral student at the University of Szeged in the early 1980s despite the fact that this interesting molecule was poorly understood at that time. She strongly believed that synthesized mRNA could be used to instruct cells to make their own medicines, and become a potent therapeutic or vaccine. In 1985 she experienced her first roadblock when she lost funding for her work. But she saw an opportunity at Temple University in Philadelphia, and decided to move her family and immigrate to the US in order to continue her research. Due to Communist restrictions on exporting money, her husband had to sell their family car on the black market and she had to then smuggle the $1200 out of the country. She took a risk and sewed the money into her 2-year-old daughter Susan’s teddy bear. Dr. Karikó and her family arrived safely in the US with the teddy bear in hand on a quest to understand mRNA. Susan later went on to win two Olympic gold medals as a member of the US rowing team.

While Dr. Karikó worked long hours trying to synthesize therapeutic mRNA, she bounced around on the fringes of academia at the University of Pennsylvania. She was occasionally demoted and always struggled to secured grant funding to obtain a permanent position. Her work was considered unorthodox and speculative. But she was undeterred. She met a fellow Penn colleague, immunologist Dr. Drew Weissman, who also became enthusiastic in the potential for mRNA. However, the duo also struggled in the lab. When they injected synthetic mRNA to mice, the rodents recognized the mRNA as “foreign,” and mounted a strong inflammatory immune response. Undeterred, Karikó and Weissman kept working until they figured out a way to alter the mRNA in a way that allowed it to evade the immune system and give the body the correct message. Karikó and Weissman further optimized the modified mRNA so that it could become more effective and also target specific areas of the body. The potential therapeutic and prophylactic effects were infinite!

In 2013, Dr. Karikó was offered a Senior Vice President position at BioNTech, the German biotech firm that eventually teamed up with Pfizer to develop the COVID-19 mRNA vaccine. She was thrilled to see her lifelong work have success in the vaccine that ultimately protected millions of people worldwide from the serious effects of COVID-19. In 2021 and 2022, Dr. Karikó’s work and critical discoveries were lauded all over the world. She was honored by her scientific peers with the prestigious Breakthrough Prize in Life Sciences, the Princess of Asturias Award, and the Vilcek Prize for Excellence in Biotechnology.