As an increasing number of obese Americans seek Ozempic and Wegovy — drugs promoted by celebrities and on TikTok as weight-loss aids — a more potent obesity drug is poised to revolutionize treatment.
Tirzepatide, an Eli Lilly and Co. drug approved to treat type 2 diabetes under the brand name Mounjaro, helped people with the disease who were overweight or obese lose up to 16% of their body weight, or more than 34 pounds, over the course of nearly 17 months, the company reported Thursday.
The late-stage study of the drug for weight loss adds to earlier evidence that participants without diabetes who received weekly injections of the drug lost up to 22% of their body weight during the same time period. For a typical patient taking the maximum dose, this equated to a weight loss of over 50 pounds.
Diabetes makes it notoriously difficult to lose weight, according to Dr. Nadia Ahmad, medical director of obesity clinical development at Lilly, so the recent findings are particularly noteworthy. “We have never seen a weight loss of this magnitude,” she said.
On the basis of the new results, which have not yet been published in their entirety, company representatives have stated that they will submit a final application to the U.S. Food and Drug Administration for fast-track approval to market tirzepatide for chronic weight management. A decision may be forthcoming later this year. A company representative would not affirm whether the drug would be marketed for weight loss under a different brand name in the United States.
If approved for weight loss, tirzepatide could become the most effective drug in an arsenal of medications that are revolutionizing the treatment of obesity, which affects more than four in ten American adults and is linked to dozens of diseases that cause disability and mortality.
Dr. Caroline Apovian, director of the Center for Weight Management and Wellness at Brigham and Women’s Hospital, stated, “If everyone with obesity in the United States lost 20% of their body weight, we could take patients off all of these medications for reflux, for diabetes, and for hypertension.” We would not recommend stent replacement for patients.
Analysts predict that tirzepatide could become one of the most popular pharmaceuticals of all time, with annual sales exceeding $50 billion. It is anticipated to outpace Novo Nordisk’s Ozempic, a diabetes drug used so frequently to lose weight that Jimmy Kimmel made a jest about it at the Oscars, and Wegovy, a version of semaglutide approved for weight loss in 2021. According to company reports, these pharmaceuticals generated nearly $10 billion in 2022, with prescriptions continuing to increase.
In separate clinical trials, tirzepatide led to greater weight loss than semaglutide, whose users lost approximately 15% of their body weight over a 16-month period. A trial contrasting the two medications is planned.
Last year, Mounjaro was first approved to treat diabetes. Since then, tens of thousands of patients have obtained the medication from physicians and telehealth providers who prescribed it “off-label” for weight loss.
Matthew Barlow, a 48-year-old health technology executive in California, reported that he has shed over 100 pounds since November by using Mounjaro and altering his diet.
“Psychologically, you don’t want to eat,” stated Barlow. Now I can consume two dessert bites and feel satisfied.
Instead of relying solely on diet, exercise, and willpower to lose weight, tirzepatide and other new medications target the digestive and chemical pathways underlying obesity, suppressing appetite and reducing food cravings.
Dr. Amy Rothberg, a University of Michigan endocrinologist who directs a virtual weight loss and diabetes program, stated, “They have completely altered the landscape.”
According to Dr. Louis Aronne, director of the Comprehensive Weight Control Center at Weill Cornell Medicine, approximately one-third of individuals will lose at least 5 percent of their body weight with diet and exercise alone. In the most recent trial of tirzepatide, greater than 86% of patients taking the highest dose lost at least 5% of their body weight. According to the manufacturer, at least 15% of those who took this dosage experienced weight loss.
The obesity medications assist in overcoming a biological mechanism that is activated by dieting, causing the body to make a concerted effort to prevent weight loss.
“That is a real physical phenomenon,” Aronne stated. A number of hormones respond to a reduction in caloric intake.
Ozempic and Wegovy are two semaglutide formulations. This drug mimics a key gut hormone called GLP-1, which is activated after people consume, increasing insulin release and decreasing sugar release from the liver. It slows digestion and suppresses appetite, prolonging fullness.
Tirzepatide is the first substance that amplifies the effects of two hormones, GLP-1 and GIP. In addition, it targets the chemical signals sent from the intestine to the brain, thereby suppressing food cravings and thoughts.
Although the drugs appear to be harmless, they can cause serious side effects. Constipation, diarrhea, nausea, vomiting, and gastrointestinal pain are the most common adverse reactions. Some users have developed pancreatitis or pancreatic inflammation, while others have experienced gallbladder issues. The product description for Mounjaro warns that it may induce thyroid tumors and cancer.
There are further disadvantages: Versions of semaglutide have been on the market for a number of years, but the long-term effects of drugs that inhibit human metabolism are still unclear. Initial evidence suggests that when patients cease taking the medications, they regain weight.
In addition, the medications are expensive and have been difficult to obtain in recent months due to intermittent shortages. Wegovy costs approximately $1,300 per month. Mounjaro, used to treat diabetes, begins at approximately $1,000 per month.
Only 20% to 30% of patients with private insurance in Apovian’s practice discover that their medications are covered. Some insurers that previously covered the drugs are instituting new regulations requiring six months of documented lifestyle modifications or a certain amount of weight loss in order to maintain coverage. Medicare is primarily prohibited from covering weight-loss drugs, despite efforts by drug manufacturers and advocates to change this.
However, according to experts, the remarkable effects of tirzepatide, Ozempic, and Wegovy demonstrate that losing weight is not merely a matter of willpower. Aronne emphasized that, like high blood pressure, which affects approximately half of American adults and is managed with medication, obesity should be regarded as a chronic disease and not a character flaw.
Rebecca Puhl, a professor at the Rudd Center for Food Policy and Health who studies weight stigma, said it remains to be seen what effect new drug treatments will have on pervasive bias against individuals with obesity. She stated that it is difficult to alter “deep-rooted beliefs about body weight and physical appearance” in American culture.
“Weight stigma could persist or worsen if medication is equated with ‘taking the easy way out’ or ‘not trying hard enough,’” she said.