FDA Alert

Tirzepatide Gains FDA Approval for Chronic Weight Management

On November 8, the FDA approved tirzepatide for chronic weight management in adults with a BMI of 27 kg/m2 or greater and a weight-related medical condition, such as hypertension, type 2 diabetes, high cholesterol.1 Tirzepatide was previously approved for treating type 2 diabetes in May 2022. Both indications are to be used in addition to  a reduced calorie diet and increased physical activity.

“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,” John Sharretts, MD, Director of the Division of Diabetes, Lipid Disorders, and Obesity in the FDA’s Center for Drug Evaluation and Research, said 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.” 

Tirzepatide, a glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonist, is administered once weekly via injection under the skin. According to the FDA, “the dosage must be increased over 4 to 20 weeks to achieve the target dosages of 5 milligram (mg), 10 mg, or 15 mg once weekly.” The maximum dosage is 15 mg once weekly.

The FDA approved tirzepatide for chronic weight management following the results of two phase 3, randomized, double-blind, placebo-controlled trials: SURMOUNT-1 and SURMOUNT-2.2,3 The trials studied adults with obesity or overweight with at least one weight-related condition. In the two trials, researchers measured weight reduction after 72 weeks in a total of 2519 patients who received either 5 mg, 10 mg or 15 mg of tirzepatide once weekly and 958 patients who received once-weekly placebo injections.

In both trials, patients who received tirzepatide had statistically significant reductions in body weight at all three dose levels when compared with those who received placebo after 72 weeks of treatment.

For example, in SURMOUNT-1, patients with obesity who received 15 mg, the highest approved dosage, lost on average 20.9% of their body weight by week 72 compared with those randomized to placebo who lost on average 3.1%.2 In SURMOUNT-2, patients with obesity and type 2 diabetes randomized to receive 15 mg lost 14.7% of their body weight, on average.3

Common adverse effects include nausea, diarrhea, vomiting, constipation, abdominal discomfort and pain, injection site reactions, fatigue, hypersensitivity reactions burping, hair loss, and gastroesophageal reflux disease.

According to the FDA, Tirzepatide should not be used by people with a history of medullary thyroid cancer or those with multiple endocrine neoplasia syndrome type 2. Tirzepatide has also not been studied in those with a history of pancreatitis or severe gastrointestinal disease.

 

Reference:

  1. FDA approves new medication for chronic weight management. News release. US Food and Drug Administration; November 8, 2023. Accessed November 8, 2023. https://www.fda.gov/news-events/press-announcements/fda-approves-new-medication-chronic-weight-management.
  2. Jastreboff AM, Aronee LJ, Ahmad NN, et al; for the SURMOUNT-1 investigators. Tirzepatide once weekly for the treatment of obesity. N Engl J Med. 2022;387:205-216. doi:10.1056/NEJMoa2206038
  3. Garvey WT, Frias JP, Jastreboff AM, et al; for the SURMOUNT-2 investigators. Tirzepatide once weekly for the treatment of obesity in people with type 2 diabetes (SURMOUNT-2): a double-blind, randomised, multicentre, placebo-controlled, phase 3 trial. Lancet. 2023;402:613-626. doi:10.1016/S0140-6736(23)01200-X