Katalin Karikó

Katalin Karikó
Born	Katalin Karikó (1955-01-17) January 17, 1955 Szolnok, Hungary
Other names	Kati Karikó
Occupation	Biochemist
Years active	1978–present
Known for	Development of mRNA technology for vaccines and therapeutics

Katalin "Kati" Karikó (, ; born January 17, 1955) is a Hungarian-American biochemist whose expertise lies in RNA-mediated processes, with a particular focus on in vitro-transcribed messenger RNA (mRNA) utilized for protein replacement therapies. She played a crucial role in establishing the scientific basis for mRNA vaccines, overcoming substantial challenges and skepticism within the research community. In recognition of her contributions, Karikó was awarded the 2023 Nobel Prize in Physiology or Medicine alongside American immunologist Drew Weissman.

From 2006 until 2013, Karikó co-founded and led RNARx as its CEO. She then joined BioNTech RNA Pharmaceuticals in 2013, where she progressed from vice president to senior vice president by 2019, remaining there until 2022 before departing to dedicate herself fully to research. The University of Szeged honored her with an honorary doctorate in 2021, where she currently holds a professorial position. Despite her affiliation with the University of Pennsylvania, which stood to gain financially from her innovations, the institution under-resourced her mRNA work, demoting her in 1995 and ultimately denying tenure. Following this, she transitioned to BioNTech after Penn declined to reinstate her.

Karikó’s research achievements include the joint discovery with Weissman of nucleoside modifications that reduce RNA's immunogenicity, a breakthrough that enabled therapeutic applications of mRNA. Together, they hold U.S. patents for nucleoside-modified RNA technology that is non-immunogenic, licensed by BioNTech and Moderna for use in protein replacement treatments and COVID-19 vaccines.

The mRNA platform developed by Karikó is fundamental to the highly effective COVID-19 vaccines produced by BioNTech/Pfizer and Moderna, which have been instrumental in managing the global health crisis. Besides receiving the Nobel Prize, Karikó and Weissman have been honored with numerous awards including the Lasker–DeBakey Clinical Medical Research Award, Time Magazine’s Hero of the Year in 2021, and the 2022 Tang Prize in Biopharmaceutical Science.

Early life and education

Katalin Karikó was born in Szolnok and grew up in Kisújszállás, Hungary, in a humble household lacking running water or modern conveniences. Her father, János, worked as a butcher while her mother was employed as a bookkeeper. Her father faced repercussions due to his participation in the 1956 Hungarian revolution. Demonstrating early aptitude in science, Karikó placed third nationally in a biology competition and consistently ranked among the top students by eighth grade, laying the foundation for her later innovations in mRNA research.

She obtained a Bachelor of Science degree in biology (1978) followed by a PhD in biochemistry (1982) from the University of Szeged. Her postdoctoral work was conducted at Hungary’s Biological Research Centre (BRC). Between 1978 and 1985, she was registered as an intelligence asset by Hungarian secret police—a designation she attributes to coercion and denies acting as an informant.

When funding for her laboratory ended in 1985, Karikó pursued opportunities abroad. She accepted a research position offered by Robert J. Suhadolnik at Temple University, which led her to relocate to the United States with her husband and their two-year-old daughter. To finance their move, they sold their car and secretly carried cash hidden inside their daughter’s teddy bear while navigating black market currency exchanges.

Career

From 1985 to 1988, Karikó served as a postdoctoral researcher at Temple University in Philadelphia, where she engaged in clinical trials involving double-stranded RNA (dsRNA) to treat patients with AIDS, hematological disorders, and chronic fatigue syndrome. This work was pioneering since the molecular basis for interferon activation by dsRNA had yet to be elucidated.

In 1988, without notifying her mentor at Temple, Karikó accepted a role at Johns Hopkins University. This led her advisor to report her to U.S. immigration officials, resulting in legal complications that delayed her employment and caused Johns Hopkins to rescind their offer. Despite facing these obstacles and struggling to find new positions due to unfavorable references, she ultimately secured a position at the Uniformed Services University of the Health Sciences in Bethesda from 1988 through 1989.

Karikó joined the University of Pennsylvania in 1989 to collaborate with cardiologist Elliot Barnathan on messenger RNA (mRNA) research. By 1990, while serving as an adjunct professor at the Perelman School of Medicine, she submitted her initial grant proposal focused on mRNA-based gene therapy. Although met with widespread skepticism from biotechnology firms and pharmaceutical companies during the 1990s, this became her central research area. After several grant rejections, she faced a demotion in 1995 but remained committed to advancing mRNA studies.

In 1997, Karikó began working alongside immunologist Drew Weissman at the University of Pennsylvania. Weissman’s financial support was instrumental in progressing their interdisciplinary efforts that combined immunology and biochemistry, overcoming significant technical barriers in mRNA technology. Their relentless dedication eventually earned recognition despite persistent challenges.

A major advancement occurred when they discovered that synthetic mRNA induced inflammatory responses in living organisms, unlike transfer RNA (tRNA). Starting in 2005, they showed that modifying nucleosides within mRNA—specifically substituting uridine with pseudouridine—significantly diminished immune activation. Although initially rejected by leading scientific journals, their research was ultimately published in Immunity.

Karikó and Weissman also engineered a lipid nanoparticle delivery system designed to shield mRNA molecules until they reached their cellular targets. This innovation proved successful in animal models and laid the groundwork for future mRNA-based therapeutics.

Together, they established RNARx and obtained patents in 2006 and 2013 covering modified nucleosides that reduce antiviral immune responses to mRNA. The University of Pennsylvania later licensed this intellectual property, which attracted interest from venture capital-backed enterprises such as Moderna.

In 2006, Karikó partnered with biochemist Ian MacLachlan to develop lipid nanoparticle formulations optimized for mRNA delivery. By early 2013, recognizing limited prospects at the University of Pennsylvania amid Moderna’s significant agreements, she joined BioNTech RNA Pharmaceuticals as vice president and later advanced to senior vice president while retaining an adjunct professorship.

During Nobel Week 2023, Karikó underscored her focus on scientific inquiry rather than accolades, emphasizing perseverance as a cornerstone of her career. In November 2024 and May 2025, she delivered prominent lectures reflecting on her Nobel journey and exploring clinical applications of mRNA therapies.

As of October 2023, Karikó holds a professorship at the University of Szeged in Hungary.

Scientific contributions

Karikó's investigations have played a crucial role in advancing the production of pluripotent stem cells, messenger RNA-based gene therapy, and the innovation of a novel category of pharmaceuticals.

Her discoveries paved the way for BioNTech and Moderna to engineer therapeutic mRNAs that do not provoke immune system activation. In 2020, the technology developed by Karikó and Weissman was fundamental to the creation of COVID-19 vaccines by BioNTech in partnership with Pfizer and by Moderna. These mRNA vaccines were formulated and authorized at an unprecedented pace, achieving efficacy rates exceeding 90%. Beyond combating infectious illnesses, mRNA technology holds potential for treating specific cancers, as well as cardiovascular and metabolic disorders such as ischemia.

Awards and honors

Karikó has been honored with more than 130 international distinctions recognizing her pioneering achievements in biochemistry.

On 2 October 2023, the Nobel Assembly at the Karolinska Institute bestowed the 2023 Nobel Prize in Physiology and Medicine upon Katalin Karikó and Drew Weissman for their development of mRNA technology.

In April 2024, Karikó contributed her Nobel Prize award, totaling over half a million dollars, to her alma mater, the University of Szeged.

In 2022, she received The Novo Nordisk Prize alongside Weissman for their decade-long innovative work on nucleoside-modified mRNA. The subsequent year, she was inducted into the National Inventors Hall of Fame in recognition of her mRNA research.

Karikó was included in the 2024 Time 100 list highlighting the most influential figures in health. In June 2024, she was honored with the Paul Karrer Medal by the University of Zurich. Later that year, she was featured on the BBC's 100 Women roster.

In May 2025, Karikó earned election to the National Academy of Sciences, acknowledging her pivotal role in advancing mRNA vaccine research.

Personal life

Karikó is married to Béla Francia, and their daughter is Susan Francia, a two-time Olympic gold medalist in rowing. Their grandson was born in the United States in February 2021 to their daughter and her husband, architect Ryan Amos.

Media visibility and memoir

In April 2021, The New York Times spotlighted Karikó's professional journey, emphasizing her foundational contributions to mRNA vaccines during the COVID-19 pandemic.

On 10 June 2021, The Daily podcast from The New York Times highlighted the obstacles Karikó faced before her scientific breakthroughs gained widespread acknowledgment.

In November 2021, the American magazine Glamour recognized her as a Woman of the Year.

Two children's books about Karikó were published in 2023: Never Give Up: Dr. Kati Karikó and the Race for the Future of Vaccines by Debbie Dadey and Juliana Oakley, along with Kati's Tiny Messengers: Dr. Katalin Karikó and the Battle Against COVID-19 by Megan Hoyt and Vivien Mildenberger.

Karikó’s autobiography, titled Breaking Through: My Life in Science, was released by Crown Publishing Group on 10 October 2023 shortly after she received the Nobel Prize. It became Hungary’s top-selling non-fiction book of 2023 and was awarded the Libri Literary Prize in June 2024 as well as the ASIMOV Prize in May 2025. By that time, her memoir had been translated into nine languages.

Selected publications

• Katalin Karikó; Breaking Through: My Life in Science (autobiography), released on 10 October 2023 by Crown Publishing Group, available in more than nine languages

See also

• Tozinameran – Pfizer-BioNTech COVID-19 vaccine sold under the name Comirnaty
• , co-founder of BioNTech
• , co-founder of BioNTech