Canadian scientist wins Breakthrough Prize for discovery of hormone used in Ozempic, Mounjaro

A Canadian researcher has won a 2025 Breakthrough Prize in Life Sciences for discovering the GLP-1 hormone used in diabetes and obesity medications — including Ozempic, Wegovy and Mounjaro — that have changed the lives of millions of people around the world.

Dr. Daniel Drucker, an endocrinologist and a clinician-scientist at the University of Toronto and the Lunenfeld-Tanenbaum Research Institute at Sinai Health, shares the $3 million US prize with four colleagues from the United States and Denmark.

They were all involved in the development of the now-famous drugs manufactured by Novo Nordisk and Eli Lilly. Drucker and three co-winners made discoveries about glucagon-like peptide-1 in their labs. The other recipient of the award, Lotte Bjerre Knudsen, who works for Novo Nordisk, led the way in developing it into medications.

The Breakthrough Prizes, often referred to as the "Oscars of Science," were handed out Saturday in Los An​geles for categories including fundamental physics and mathematics, in addition to life sciences.

The Breakthrough Foundation says the prizes were created to "celebrate the wonders of our scientific age." Another Canadian, Maaike van Kooten of National Research Council Canada, shared a $100,000 US prize called New Horizons in Physics with two international colleagues for work in optics to view exoplanets.

In an interview in the week prior to the event, Drucker said the prize is meaningful because it's awarded by other scientists and "gets a lot of attention in the scientific community."

"We have students and trainees and awards like this tell them that the world is watching and thinks the work is meritorious. And I think that's just great for morale and for young people," he said.

Drucker began his journey studying genetic sequencing of glucagon-like peptides at a lab in Boston in the 1980s, then returned to Canada and continued his work at the University of Toronto.

He spoke with The Canadian Press about those early days, what he thinks about how the resulting medications have changed the world's view of obesity and what other health issues GLP-1 might address in the future.

This interview has been edited for length and clarity.

When you started at that lab in Boston, why were you studying this particular hormone?

"There were probably about a dozen projects in the lab at that time. So some people were working on pituitary hormones. Some people were on basic cell biology projects. Other people were working on different genes and glucagon was one of the projects in the lab.... It just so happened when I got there, they said, 'OK Drucker, you work on the glucagon gene.' [It] could have been another gene [and] you never would have heard from me again.

Were there any key moments where you thought, 'Wow, this is a big deal?'

"I don't think there was any one 'Eureka!' moment, but I will say the potential importance dawned on me when I walked into the lab one day and my notebooks were gone. And I said, 'Oh my gosh, someone broke into the lab and stole my notebooks.' And then it turned out no — my supervisor [and a fellow prize winner], Joel Habener, took my notebooks because he was excited enough about the results to file a patent."