FDA Approves Tirzepatide for Chronic Weight Management

The FDA has approved tirzepatide (Zepbound; Eli Lilly and Co) injection for chronic weight management in adults with obesity or overweight with at least 1 weight-related condition such as high blood pressure, type 2 diabetes, or high cholesterol. It should be used in combination with a reduced calorie diet and increased physical activity.¹

Image credit: Natalia | stock.adobe.com

Tirzepatide is already approved under the brand name Mounjaro (Lilly) to be used along with diet and exercise to improve blood sugar in adults with type 2 diabetes.¹

“Unfortunately, despite scientific evidence to the contrary, obesity is often seen as a lifestyle choice—something that people should manage themselves,” said Leonard Glass, MD, senior vice president of global medical affairs at Lilly Diabetes and Obesity, in a press release. “For decades, diet and exercise have been a go-to, but it’s not uncommon for a person to have tried 20 to 30 times to lose weight with this approach. Research now shows the body may respond to a calorie-deficit diet by increasing hunger and reducing feelings of fullness, making weight loss more difficult.”²

Approximately 70% of adults in the US have obesity or overweight, and many of those individuals have a weight-related condition. Losing 5% to 10% of body weight through diet and exercise has been shown to reduce risk of cardiovascular disease in adults with obesity or overweight.¹

“Obesity and overweight are serious conditions that can be associated with some of the leading causes of death such as heart disease, stroke, and diabetes,” said John Sharretts, MD, director of the Division of Diabetes, Lipid Disorders, and Obesity in the FDA’s Center for Drug Evaluation and Research, in a press release. “In light of increasing rates of both obesity and overweight in the United States, today’s approval addresses an unmet medical need.”¹

Tirzepatide activates glucagon-like peptide-1 and glucose-dependent insulintropic polypeptide to reduce appetite and food intake. It is administered by subcutaneous injection once weekly and the dosage is increased over 4 to 20 weeks to the target dosages of 5 mg, 10 mg, or 15 mg once weekly. The maximum dosage is 15 mg once weekly.¹

Its efficacy for chronic weight management in combination with a reduced-calorie diet and increased physical activity was established in 2 randomized, double-blind, placebo-controlled trials with adults with obesity or overweight and at least 1 weight-related condition. The studies measured weight reduction after 72 weeks in a total of 2519 patients who received tirzepatide and 958 patients who received placebo.¹

In both trials, after 72 weeks of treatment, patients who received tirzepatide at all 3 dose levels experienced a statistically significant reduction in body weight compared to those who received placebo, and greater proportions of patients who received tirzepatide achieved at least 5% weight reduction compared to placebo.¹

The larger of the 2 trials enrolled adults without diabetes. At the start of the trial, the average body weight of participants was 231 pounds (105 kg) and average body mass index (BMI) was 38 kg/m2. In this trial, individuals randomized to receive the highest approved dosage of tirzepatide lost an average 18% of body weight compared to those randomly assigned to placebo.¹

At the start of the trial in adults with type 2 diabetes, the average body weight was 222 pounds (101 kg) and the average BMI was 36 kg/m2. Those who received the highest approved dose of tirzepatide lost an average 12% of their body weight compared to those on placebo.¹

Adverse effects of tirzepatide can include nausea, diarrhea, vomiting, constipation, abdominal discomfort and pain, injection site reactions, fatigue, hypersensitivity reactions (typically fever and rash), burping, hair loss, and gastroesophageal reflux disease. Tirzepatide causes thyroid C-cell tumors in rats and it is unknown whether it causes such tumors, including medullary thyroid cancer, in humans.¹

In a press release, Mike Mason, executive vice president of Lilly Diabetes and Obesity, said the company is working to ensure that patients have access to this new treatment.²

“Far too many hurdles continue to prevent people living with obesity from accessing obesity treatments that could lead to significant weight loss,” Mason said. “Broader access to these medications is critical, which is why Lilly is committed to working with health care, government, and industry partners to ensure people who may benefit from Zepbound can access it.”²

The drug is expected to be available in the United States by the end of the year in 6 doses (2.5 mg, 5 mg, 7.5 mg, 10 mg, 12.5 mg, 15 mg) at a list price of $1059.87, which is approximately 20% lower than semaglutide 2.4 mg injection for weight loss. Lilly is implementing a commercial savings card program to improve patient access to Zepbound.²

References

1. FDA Approves New Medication for Chronic Weight Management. FDA. November 8, 2023. Accessed November 8, 2023.

2. FDA Approves Lilly’s Zepbound (tirzepatide) for Chronic Weight Management, a Powerful New Option for the Treatment of Obesity or Overweight with Weight-Related Medical Problems. Lilly. November 8, 2023. Accessed November 8, 2023. https://investor.lilly.com/news-releases/news-release-details/fda-approves-lillys-zepboundtm-tirzepatide-chronic-weight