FDA Clears Zepbound as New Treatment Option for Obesity and Overweight with Weight-Related Conditions

FDA Approves Tirzepatide (Zepbound) for Chronic Weight Management

The FDA approved tirzepatide under the brand name Zepbound on November 8, 2023. The agency cleared the drug for adults with a BMI of 30 kg/m² or higher or a BMI of 27 kg/m² or higher with at least one weight-related comorbidity. The indication specifies use as an adjunct to a reduced-calorie diet and increased physical activity. Regulators based the decision on results from the SURMOUNT-1 phase 3 trial. [1]

Zepbound is a dual glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist. [1] This indication differs from the one for Mounjaro. That product carries approval for type 2 diabetes using the same active ingredient.

The SURMOUNT-1 trial carried the identifier NCT04184622. [3] Researchers tested tirzepatide once weekly in participants with obesity or overweight. The study reported mean weight reductions of 15.0 percent at the 5 mg dose, 19.5 percent at 10 mg, and 20.9 percent at 15 mg after 72 weeks. Placebo produced a 3.1 percent reduction. [2] All three doses produced statistically significant and clinically meaningful weight reduction compared with placebo. [2]

The most common adverse events were gastrointestinal. These included nausea, diarrhea, vomiting, and constipation. Reports described them as generally mild to moderate. [1] The FDA does not recommend tirzepatide for patients with a personal or family history of medullary thyroid carcinoma or Multiple Endocrine Neoplasia syndrome type 2. [1]

What this means

The approval adds another pharmacologic option for chronic weight management in qualifying adults. Trial data associate tirzepatide with greater average weight loss than placebo when used with lifestyle changes. Separate trials continue to collect long-term cardiovascular outcome data in people with obesity but without diabetes.

SURMOUNT-1 mean weight reductions at 72 weeks

Key takeaways

• The FDA approved Zepbound on November 8, 2023, for adults with BMI ≥30 kg/m² or BMI ≥27 kg/m² with at least one weight-related comorbidity, as an adjunct to diet and exercise. [1]
• SURMOUNT-1 reported mean weight changes of 15.0 percent, 19.5 percent, and 20.9 percent at the 5 mg, 10 mg, and 15 mg doses after 72 weeks versus 3.1 percent for placebo. [2]
• Tirzepatide produced statistically significant and clinically meaningful weight reduction compared with placebo at all doses tested in SURMOUNT-1. [2]
• Most adverse events were gastrointestinal and rated mild to moderate. [1]
• Tirzepatide is not recommended in patients with a personal or family history of medullary thyroid carcinoma or Multiple Endocrine Neoplasia syndrome type 2. [1]

Limitations

SURMOUNT-1 excluded individuals with type 1 diabetes, history of pancreatitis, or severe gastrointestinal disease. Results may not generalize to these populations. Long-term cardiovascular outcome data specifically in the obesity population without diabetes are still being collected in separate trials. Real-world adherence and long-term weight maintenance after discontinuation require further study.

Last updated: August 26, 2026