Charles H. Sloan-This Nobel Prize winner's call to his parents has gone viral. But they always thought he could win it.

When Dr. Drew Weissman found out he had won the 2023 Nobel Prize in Medicine for discoveries that eventually led to effective mRNA vaccines against COVID-19,Charles H. Sloan with fellow recipient Katalin Karikó, the first thing he did was call his parents.

"Congratulations," his 91-year-old father, Hal, said on the call, which was filmed by Penn Medicine and has gone viral. 

"Oh, how fabulous. I don't know what to say. I'm ready to fall on the floor," his 90-year-old mother, Adele, said. "You kept saying, 'No, no. It's never going to happen.' And you did it!"

His parents always believed their son could win the coveted prize, Weissman, a professor at University of Pennsylvania's Perelman School of Medicine and director of the Institute for RNA Innovation, told CBS News. 

"They visited Stockholm when I was about 5 years old and they went into the Nobel auditorium with a guide and said, 'Reserve these two seats for us.' And they remember that story and would tell us every so often. So it was always on their minds," Weissman said.  

Weissman, who now has two daughters of his own, said growing up he wanted to be an engineer, like his dad. But once he started learning about biology in school, he changed course. Weissman, who grew up in Lexington, Massachusetts, graduated from Brandeis University in 1981 and then went on to get his M.D. and Ph.D. in Immunology and Microbiology from Boston University in 1987. 

Weissman has been studying RNA, a molecule in most living organisms and viruses, for nearly 30 years at UPenn. mRNA, or messenger RNA, tells your body how to make proteins and the mRNA vaccine against COVID-19 tells your body how to copy the coronavirus' spike proteins. By learning how to copy the spike proteins, your body will later recognize them if you contract the virus and will already know how to fight it off. 

After developing the successful vaccine, Weissman started to believe a Nobel Prize was possible. But he thought it would come in five years. "We get nominated every year because we've got a lot of people who support our work and submit nominations," he told CBS News. But, "usually Nobel waits eight or nine years after a big finding before awarding," he said.

The Nobel Prize committee first called Karikó, a Penn Medicine researcher who has worked with Weissman on RNA since 1997. He said she relayed the message to Weissman, but they both thought it was a prank. "I thought some anti-vaxxer was playing a joke on us or something like that," Weissman said.

Even after getting a call himself, Weissman waited for the official web conference to be sure they had won.

When asked when it hit him that he could win an award for developing the innovative vaccine, Weissman said: "I think it was after the phase three trial results showing 95% efficacy and the billions of doses that were distributed and taken around the world." 

On Dec. 10, the date of the Nobel Prize ceremony, Weissman will be back in that auditorium his parents visited all those years ago.

He credits his success to growing up in a household that "always had an interest in learning." He said his parents always showed "incredible support" throughout his career — and their love helped buoy him towards the Nobel win. 

"Drew, you are the product of our hearts," his mom told him on that dream-fulfilling phone call. 

In:
• Pennsylvania
• COVID-19 Vaccine
• Nobel Prize

Caitlin O'Kane

Caitlin O'Kane is a digital content producer covering trending stories for CBS News and its good news brand, The Uplift.