The maker of Ozempic and Wegovy is researching groundbreaking new drugs to stop people from becoming obese in the first place

Ozempic is pictured in a pharmacy on April 13, 2023 in Niesky, Germany.
Sales of diabetes drug Ozempic have boomed as doctors prescribe it for weight loss, an off-label use.
Florian Gaertner—Photothek/Getty Images

The blockbuster obesity drugs Ozempic and Wegovy have sent sales soaring for Danish pharma company Novo Nordisk, up 25% year over year in the first quarter of 2023 alone, and the company forecasts more growth this year. But even as Novo Nordisk enjoys mammoth success from its inventions, its scientists have begun working on the next generation of weight-loss drugs they believe could eclipse the booming market of those currently available: drugs to keep people from becoming obese in the first place.

“The real big frontier is when we start to talk about prevention,” Marcus Schindler, Novo Nordisk’s chief scientist and executive vice president for research and early development, told Fortune in mid-June, sitting in the airy top-floor lounge in the company’s headquarters near Copenhagen. “There are particular biological systems that kick in earlier, before you actually have full-blown obesity,” he says. “We are starting to ask, ‘What if we could stop those processes from happening?’”

Answering that question has become a major preoccupation of Novo Nordisk, while competitors like Eli Lilly and Pfizer race to catch up to Novo Nordisk’s obesity drug sales. Whichever company can figure out how to stop people from gaining weight to begin with will unlock untold fortunes in drug sales. Novo predicts its revenues from the current obesity drugs will top $3.66 billion a year by 2025. Morgan Stanley estimates that the global market for weight-loss drugs could rise more than 2,000% this decade, from $2.4 billion a year in 2022 to $54 billion by 2030.

That growth is dizzying and doesn’t even take into account possible new inventions by Novo Nordisk and others.

Ozempic’s and Wegovy’s limitations and long-term effects

New drugs could take years to develop, but Schindler believes they are on their way. Last month, Novo Nordisk launched an in-house obesity prevention unit to begin researching new weight-loss drugs. Schindler says the aim is to overcome the main limitations of Ozempic and Wegovy: the fact that the prescription drugs are administered only once patients are already suffering from Type 2 diabetes or have become medically obese. And second, that they work only so long as people take them. Just like conventional dieting, much of the weight could return once patients go off the medications.

Ozempic was approved by the Food and Drug Administration in 2017 to treat Type 2 diabetes, while Wegovy was approved two years ago for weight loss. Over the past year, demand squeezed Wegovy supplies, so dieters asked their doctors to prescribe Ozempic for weight loss, an off-label use. Ozempic sales soared as a result. Novo Nordisk says the U.S. accounted for most of its global sales last year.

The logo of Danish pharmaceutical company Novo Nordisk is pictured at their headquarters in Bagsvaerd outside of Copenhagen, Denmark on February 1, 2017
Novo Nordisk is still riding its Ozempic- and Wegovy-driven sales boom as it hunts for the next big thing.
LISELOTTE SABROE—Scanpix Denmark/AFP/Getty Images

Both drugs are so-called semaglutides. They mimic a hormone Novo Nordisk discovered in the 1980s that makes people feel full even after a small amount of food. The invention has proved a major breakthrough, allowing people on Ozempic and Wegovy to lose 10% to 15% of their body weight relatively quickly, depending on one’s metabolism—something Schindler says scientists had always thought was “close to impossible.”

But despite their huge popularity in the U.S. as diet drugs, Ozempic and Wegovy were not intended for use as ongoing weight-loss methods, and Schindler says scientists do not yet know what happens if people take them over long periods of time. Wegovy has only been on the market for two years. “We simply don’t have enough data yet in what will happen in the body. Will it remodel?” he says. “We don’t know that yet. It is way too early to say.”

The gene that causes obesity

That has led Schindler and others to start thinking about how to halt obesity before it starts. The research would likely involve identifying people’s genetic makeup. Schindler says that “relies heavily on the quality of those early, early symptoms or markers.” He compares the new work to breakthroughs in cancer research, which has helped pinpoint genetic characteristics showing how likely someone is to develop certain types of cancer in the future. “Possibly you could do the same for obesity,” he says. Finding those genes could then determine what drugs to develop to prevent obesity and help people maintain stable weight. Among the clues researchers are looking for is why some obese people develop medical complications while others do not.

Few expect rapid answers. Novo Nordisk is accustomed to lengthy drug research. “It is very early days, and it will take a long time to do it,” says Novo’s executive vice president Camilla Sylvest, who is an economist. “But if we don’t start now it will take even longer.”

While the company’s scientists hunt for how to prevent weight gain, Schindler thinks other advances might come sooner. That includes making Ozempic and Wegovy more effective in helping severely obese people keep the weight off long term, even after they stop taking the drugs—something the drugs are still not powerful enough to do. Novo Nordisk also hopes to develop new-generation drugs that can last for months. Right now, Ozempic and Wegovy are administered by weekly shots, which patients give themselves. “What if it wasn’t every week, but every month?” Schindler says. Eventually, an anti-obesity shot could become like a COVID-19 vaccine, delivered infrequently by a doctor or pharmacist. “I’m particularly interested in how we can make medicines simply more accessible,” he says. “What are the features of our drugs that would help to give it to a broader population?”

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