Katalin Kariko and Drew Weissman won the Nobel Medicine Prize on Monday for work on messenger RNA (mRNA) technology that paved the way for groundbreaking Covid-19 vaccines.
The pair, who had been tipped as favourites, "contributed to the unprecedented rate of vaccine development during one of the greatest threats to human health in modern times," the jury said.
In honouring the pair this year, the Nobel committee in Stockholm broke with its usual practice of honouring decades-old research.
While the prize-winning science dates back to 2005, the first vaccines to use the mRNA technology were those made by Pfizer/BioNTech and Moderna against Covid-19.
Kariko of Hungary and Weissman of the United States, longstanding colleagues at the University of Pennsylvania, have won a slew of awards for their research, including the prestigious Lasker Award in 2021, often seen as a precursor to the Nobel.
Unlike traditional vaccines which use a weakened virus or a key piece of the virus' protein, mRNA vaccines provide the genetic molecules that tell cells what proteins to make, which simulates an infection and trains the immune system for when it encounters the real virus.
The idea was first demonstrated in 1990, but it wasn't until the mid-2000s that Weissman and Kariko developed a technique to control a dangerous inflammatory response seen in animals exposed to these molecules, opening the way to develop safe human vaccines.