STOCKHOLM - Hungarian scientist Katalin Kariko and U.S. colleague Drew Weissman, who met in line for a photocopier before making mRNA molecule discoveries together that paved the way for COVID-19 vaccines, won the 2023 Nobel Prize for Medicine on Monday.
"The laureates contributed to the unprecedented rate of vaccine development during one of the greatest threats to human health in modern times," the Swedish award-giving body said in the latest accolade for the pair.
The prize, among the most prestigious in the scientific world, was selected by the Nobel Assembly of Sweden's Karolinska Institute medical university and comes with 11 million Swedish crowns (about $1 million) to share between them.
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.
The two laureates jointly developed so-called nucleoside base modifications, which stop the immune system from launching an inflammatory attack against lab-made mRNA, previously seen as a major hurdle against any therapeutic use of the technology.
German biotech firm BioNTech said in June that about 1.5 billion people had received its mRNA shot, co-developed with major drugmaker Pfizer, across the world.
The European Medicines Agency (EMA) earlier this year cited estimates that in the first year of the pandemic alone, coronavirus vaccines were estimated to have helped save almost 20 million lives globally. BioNTech and Pfizer's mRNA vaccines were the most widely-used COVID shots used in the Western world.
The Nobel winners 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.
COVID HEROES
"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.
"Together they have saved millions of lives, prevented severe COVID-19, reduced the overall disease burden and enabled societies to open up again."
Messenger or mRNA, discovered in 1961, is a natural molecule that serves as a recipe for the body’s production of proteins. To use man-made mRNA to instruct human cells to make therapeutic proteins, long regarded as impossible, was commercially pioneered during the pandemic.
The technology means a radical break from established biotech medicines, which are generated in complex reactors by genetically modified living cells, then isolated and purified.
Messenger RNA, by contrast, works like a software that can be injected into the body to instruct human cells to churn out the desired proteins.
Vaccination stimulates the formation of an immune response to a particular pathogen. This gives the body a head start in the fight against disease in the event of a later exposure. Vaccines based on killed or weakened viruses have long been available, exemplified by the vaccines against polio, measles, and yellow fever. In 1951, Max Theiler was awarded the Nobel Prize in Physiology or Medicine for developing the yellow fever vaccine.
The progress in molecular biology in recent decades, vaccines based on individual viral components, rather than whole viruses, have been developed. Parts of the viral genetic code, usually encoding proteins found on the virus surface, are used to make proteins that stimulate the formation of virus-blocking antibodies. Examples are the vaccines against the hepatitis B virus and human papillomavirus. Alternatively, parts of the viral genetic code can be moved to a harmless carrier virus, a “vector.” This method is used in vaccines against the Ebola virus. When vector vaccines are injected, the selected viral protein is produced in our cells, stimulating an immune response against the targeted virus.
Producing whole virus-, protein- and vector-based vaccines requires large-scale cell culture. This resource-intensive process limits the possibilities for rapid vaccine production in response to outbreaks and pandemics. Therefore, researchers have long attempted to develop vaccine technologies independent of cell culture, but this proved challenging.
2023 medicine laureates Katalin Karikó and Drew Weissman published their results in a seminal 2005 paper that received little attention at the time but laid the foundation for critically important developments that have served humanity during the COVID-19 pandemic.