Scientists who spurred development of mRNA COVID-19 vaccines win Nobel medicine prize

Scientists Katalin Kariko and Drew Weissman won the 2023 Nobel Prize in Physiology or Medicine for discoveries they made at the University of Pennsylvania that enabled the development of effective vaccines against COVID-19, the award-giving body said on Monday.

Kariko and Weissman were honoured for "their discoveries concerning nucleoside base modifications that enabled the development of effective mRNA vaccines against COVID-19," the body said.

"MRNA vaccines, together with other COVID-19 vaccines, have been administered over 13 billion times. Together they have saved millions of lives, prevented severe COVID-19, reduced the overall disease burden and enabled societies to open up again," said Thomas Perlmann, member of the Nobel Assembly at the Karolinska Institute.

The Nobel Prize was created by wealthy Swedish inventor Alfred Nobel, who in his will dictated that his estate should be used to fund "prizes to those who, during the preceding year, have conferred the greatest benefit to humankind." The first awards were given out in 1901.

Kariko was senior vice-president and head of RNA protein replacement at BioNTech until 2022 and has since acted as an adviser to the company. She is also a professor at the University of Szeged in Hungary and adjunct professor at the University of Pennsylvania's Perelman School of Medicine.

Weissman is professor in vaccine research at the Perelman School.

Kariko found a way to prevent the immune system from launching an inflammatory reaction against lab-made mRNA, previously seen as a major hurdle against any therapeutic use of mRNA.

Together with Weissman, she showed in 2005 that adjustments to nucleosides, the molecular letters that write the mRNA's genetic code, can keep the mRNA under the immune system's radar.

"So this year's Nobel Prize recognizes their basic science discovery that fundamentally changed our understanding of how mRNA interacts with the immune system and had a major impact on society during the recent pandemic," said Rickard Sandberg, member of the Nobel Assembly at Karolinska Institute.

Traditionally, making vaccines required growing viruses or pieces of viruses - often in giant vats of cells or, like most flu shots, in chicken eggs, and then purifying them before next steps in brewing shots.

The messenger RNA approach is radically different. It starts with a snippet of genetic code that carries instructions for making proteins. When the right virus protein is targeted, the body turns into a mini vaccine factory.

Pfizer, in partnership with BioNTech, and Moderna were able to develop mRNA vaccines based on the foundational work conducted by Kariko and Weissman, as well as other scientists, enabling a rapid response as a COVID-19 pandemic was declared by the World Health Organization in mid-March 2020.

Since that time, a vocal anti-vaccine movement has emerged. Olle Kämpe of the Karolinska Institute, responding to a reporter question, said the award would probably not sway those most resistant to receiving vaccines, but that, "giving a Nobel Prize for this COVID-19 vaccine may make hesitant people take the vaccine and be sure it's very efficient and safe."

Gunilla Karlsson Hedestam, also from the institute, said scientists must be transparent and communicate clearly to wider audiences. While the clinical trials for COVID-19 vaccines were accelerated, she said, it was important for people to undertstand that the origins of the work enabling the development of mRNA vaccines date back to the 1990s.