The Food and Drug Administration on Wednesday approved an obesity drug from the company Eli Lilly that will be a direct competitor to the popular Wegovy.
The drug is called tirzepatide and will be sold under the name Zepbound. It joins a class of new drugs that are transforming obesity, a disease that affects 100 million American adults and is linked to a wide range of conditions, including diabetes, heart disease, sleep apnea, liver disease, kidney disease and joint pain.
Patients who used tirzepatide lost an average of 18 percent of their body weight, according to the FDA., when taken at its highest dose in a drug trial. That’s compared with Wegovy, made by Novo Nordisk, which resulted in an average weight loss of 15 percent.
The FDA has approved Zepbound for obese people and for those who are overweight and have at least one obesity-related disease.
Tirzepatide is already approved for diabetes under the brand name Mounjaro, where it competes with Novo Nordisk’s diabetes drug semaglutide, better known as Ozempic. But until now, Wegovy – also semaglutide but with a higher maximum dose than Ozempic – was the only approved drug capable of safely causing substantial weight loss only in people with obesity.
Zepbound’s side effects, similar to those of Wegovy, Ozempic, and Mounjaro, are primarily gastrointestinal, such as nausea and diarrhea. Most patients tolerated or overcame them.
In a press release, Dr. John Sharretts, director of the Division of Diabetes, Lipid Disorders, and Obesity at the FDA’s Center for Drug Evaluation and Research, said: “In light of the rates increasing rates of obesity and overweight in the United States, the approval addresses an unmet medical need.
Susan Yanovski, co-director of the Office of Obesity Research at the National Institute of Diabetes and Digestive and Kidney Diseases, said: “Just a few years ago, it would have been difficult to imagine two drugs like semaglutide and tirzepatide that cause weight loss that previously was only seen when people had bariatric surgery,” referring to a surgical treatment that has been shown to be effective for obesity.
This approval comes at a time when Novo Nordisk is unable to produce enough Wegovy to satisfy the enormous demand for the drug. Tirzepatide, which patients take as a self-administered injection once a week, as they do with Wegovy, could alleviate these shortages.
Competition could also drive down the net prices of the two drugs, or the amount actually spent by payers. Listing and net pricing are high for Wegovy.
“You would want price competition to happen as soon as possible,” said Craig Garthwaite, a health care economist at Northwestern University. Once people start taking one of these drugs, he says, “they’re locked in.” They resist change even if a competing drug costs less.
The development of Zepbound began in 2017 with a small study involving 300 people with type 2 diabetes. After 3 months, many lost at least 13 percent of their weight. Eli Lilly presented the data at a diabetes meeting in Germany. Some in the audience gasped.
Next came a large 72-week study sponsored by Eli Lilly of tirzepatide in 2,539 obese people.
In a packed room at an American Diabetes Association meeting last year, the studyThe study’s lead researcher, Dr. Ania Jastreboff of Yale, revealed the findings. More than half of patients receiving the highest dose lost at least 20 percent of their body weight. No medication has ever caused such significant weight loss.
For Eli Lilly, the results constitute the culmination of research begun ten years ago. But like Novo Nordisk, the company was trying to produce a new diabetes drug.
“Obesity was not a priority for us,” said Dr. Daniel Skovronsky, chief scientific and medical officer at Eli Lilly, adding that “it was not seen as a business opportunity.”
The sad story of weight-loss drugs was a lesson, he thought. “There has never been an effective drug for obesity,” he said, “and previous drugs have not caused enough weight loss to have an impact on people’s health.”
But Eli Lilly researchers had begun to study a diabetes drug combining two molecules. One molecule acts as a hormone, GLP-1, which prompts the body to secrete insulin when blood sugar levels rise. This was similar to the effects of Novo Nordisk’s Ozempic and Wegovy. And like these drugs, it also suppresses the appetite.
But more than one hormone is involved in blood sugar regulation. So the company’s scientists decided to try combining the molecule that mimics GLP-1 with a second molecule that acts like the gut hormone GIP. Although GIP had a more modest effect when administered alone, it amplified the effect of GLP-1 when the two hormone mimics were combined.
In mice, the combination of two drugs not only reduced blood sugar levels, but also had a profound effect on weight. It was “the biggest weight loss we’ve ever seen,” Dr. Skovronsky said.
The company’s scientists tested the drug on healthy volunteers. Even if they didn’t suffer from obesity, people lost weight.
Suddenly, Eli Lilly’s opinion on the weight loss study changed.
“We thought, ‘This drug can change the world,’” Dr. Skovronsky said. “We said, ‘This is the one.’ This is our priority.
They decided to accelerate development with an approach known as “investment at risk” in which they do not wait for each testing stage to be completed to begin the next, and in which they begin to develop their capabilities manufacturing before the studies are completed. The result was a record pace for the company: six years from the first dose in human volunteers to FDA approval. A similar strategy was also used to accelerate Covid vaccine development.
The hope is that Zepbound can reduce the chances of obese people developing the life-threatening complications that accompany the condition.
But Zepbound is just the beginning for Eli Lilly. The company and other pharmaceutical makers are working on drugs that could be even more powerful.
Lilly’s next drug adds glucagon, another gut hormone, to the two drugs in Zepbound. It appears to boost metabolism and extract fat from the liver.
And, like Novo Nordisk and other companies, Eli Lilly is working on a tablet form of tirzepatide. It is currently undergoing clinical trials.
Manufacturing injectable medications is complicated and difficult. The pills are simpler and cheaper, which could improve the supply problem affecting patients who use Ozempic and Wegovy.
It is estimated that by 2030, one billion people worldwide will be obese.
“All the companies in the world can’t do that many injections,” Dr. Skovronsky said. “It is clear that if we are to meet the needs of the global epidemic, we need oral medications. »
