Physician and scientist Drew Weissman, who earned both an MD and a PhD at Boston University, and his research collaborator Katalin Karikó won the 2023 Nobel Prize in Physiology or Medicine for their pioneering work developing the technology that powers the Pfizer-BioNTech and Moderna COVID-19 vaccines.

Those two vaccines are among the most widely distributed coronavirus vaccines worldwide. They are being used in more than 200 countries to help contain the spread of the deadly virus that upended global society in early 2020 and has so far killed nearly 7 million people and infected nearly 770 million.

“The laureates contributed to the unprec- edented rate of vaccine development during one of the greatest threats to human health in modern times,” the Nobel committee said in a statement. The committee praised the scientists for their “groundbreaking findings” that “fundamentally changed our understanding of how mRNA interacts with our immune system.”

“It’s an incredible honor,” says Weissman (CAMED’87, GRS’87, Hon.’23). “We couldn’t have come to the result without both of us being involved.” He adds, “The future is just so incredible. We’ve been thinking for years about everything that we could do with RNA, and now it’s here.”

Weissman, 64, who grew up in Lexington, Mass., did his undergraduate work at Brandeis University and his graduate work at BU, focusing on immunology and micro- biology. He is a professor of medicine and the Roberts Family Professor in Vaccine Research at the University of Pennsylvania Perelman School of Medicine.

Weissman and Karikó, 68, a biotech executive, researched so-called messenger RNA, or mRNA, a molecule essential in pro- tein production. While Weissman’s research dates to the 1990s, the breakthrough by the two came in 2005, when they discovered that adding altered mRNA to cells could trigger production of any desired protein—a feat that could revolutionize therapeutics and vaccines to treat and prevent devastat- ing diseases and infections.

To create immunity against the SARS- CoV-2 virus responsible for COVID infec- tions, mRNA vaccines instruct cells to make the coronavirus’ hallmark “spike” proteins. Those proteins nestle on the surface of
the virus, causing COVID; when a person’s immune system detects the protein on a cell’s surface, it makes antibodies that pro- tect against COVID. The mRNA vaccines trigger the body into producing those spike proteins, and the antibodies necessary to destroy them, thus providing protection against coronavirus without risking the health consequences of having to build immunity by catching the virus itself.

Weissman and Karikó’s paper about their discovery was initially rejected by several scientific publications. When Immunity pub- lished it in 2005, few scientists took notice. Finally, Moderna and German firm BioNTech used the mRNA technology to research vac- cines. Then COVID-19 struck in late 2019, and the rest became Nobel history.

Speaking to Bostonia in 2021, Weissman reflected on the day when he and Karikó received their own vaccine shots together, in December 2020: “It was an emotional moment. There were a lot of down times,
a lot of soul-searching, a lot of figuring out why things weren’t working. But we never lost hope because we both saw the incredi- ble potential that mRNA had.”

The Associated Press contributed to this article. ●