In the spring of 2002, a Danish researcher named Thomas Kruse was asked to do something he was initially reluctant to do: leave his expertise in organic chemistry behind to study peptides. At the time, he couldn't have known that this career shift would lead to one of the most significant breakthroughs in the history of treating diabetes and obesity.
The mission was daunting. Kruse, along with chemist Jesper Lau and technician Paw Bloch, set out to create a version of GLP-1, a natural hormone that helps the body produce insulin and regulate appetite.
The problem with natural GLP-1 is that it only lasts for a few minutes in the body before it is broken down. To make it useful as a medicine, the team needed to find a way to make it last for an entire week while remaining powerful enough to work. It was a massive technical puzzle that required solving issues of stability and potency all at once.
The road to success was paved with failure. The team synthesized hundreds of variations, testing one after another. Semaglutide was actually compound number 217—meaning there were 216 previous versions that simply didn't work well enough.
The breakthrough finally came through a clever piece of chemical engineering: the scientists attached a fatty acid to the molecule. This allowed the drug to bind to a common blood protein called albumin. This protein acted like a protective shield, preventing the kidneys from breaking the drug down and allowing it to circulate in the body for much longer.
To their surprise, this "shield" didn't just make the drug last longer; it also made it more potent at regulating blood sugar and appetite than anything they had seen before.
There will soon be over two billion people living with obesity, overweight, or diabetes worldwide - and Novo Nordisk scientists aim to help as many of them as possible with options that fit their needs and preferences.
Today, semaglutide has evolved from a once-weekly injection into oral versions for weight management. While it started as a treatment for blood sugar, clinical trials now suggest it could help treat cardiovascular, kidney, and liver diseases as well.
The impact of this discovery goes beyond individual patients; it is changing the way we think about public health and the economy1:
- Reducing Hospital Stays: Research in the UK suggests that these types of medicines could reduce hospitalizations and "bed days" by nearly 10%.
- Saving Money: By reducing complications from chronic diseases, semaglutide could save the UK healthcare system approximately £1.68 billion by 2040.
- Sustainable Healthcare: With global costs for chronic diseases expected to soar to $15.9 trillion by 2050, scaling access to this medicine offers a path toward more sustainable public finances.
While Thomas Kruse and Jesper Lau hold the patent, they emphasize that bringing this molecule to life was a team effort involving experts across the entire company. What began as a "reluctant" move into a new field of chemistry has ended up changing millions of lives and providing a new tool to fight some of the world's most pressing health challenges.
Novo Nordisk. Unlocking the full value of GLP‑1 for people, health systems and society. 2025. Available at: www.novonordisk.com/content/dam/nncorp/global/en/media/ pdfs/novonordisk-unlocking-the-power-of-glp-1.pdf.