How effective is Ozempic (semaglutide) for weight loss in obesity?

From the Guidelines

Ozempic (semaglutide) is highly effective for weight loss in obesity, with clinical trials showing significant weight reductions, and is recommended as a first-line treatment option for adults with obesity or overweight with weight-related complications who have had an inadequate response to lifestyle interventions. The medication works by mimicking GLP-1, a hormone that regulates appetite and food intake, and is most effective when combined with lifestyle modifications including caloric restriction and increased physical activity 1.

Key Considerations

• The standard starting dose is 0.25mg weekly by subcutaneous injection, gradually increasing to minimize gastrointestinal side effects, with the maintenance dose typically being 1mg or 2.4mg weekly depending on the formulation used 1.
• Common side effects include nausea, vomiting, diarrhea, and constipation, which often improve over time 1.
• Treatment is generally long-term as weight regain commonly occurs if the medication is stopped.
• Patients should be aware that Ozempic requires a prescription, may not be covered by insurance for weight loss specifically, and is contraindicated in certain conditions including personal or family history of medullary thyroid cancer or Multiple Endocrine Neoplasia syndrome type 2.

Recommendations

• The American Gastroenterological Association recommends adding pharmacological agents, including semaglutide 2.4 mg, to lifestyle interventions for adults with obesity or overweight with weight-related complications who have had an inadequate response to lifestyle interventions 1.
• Semaglutide 2.4 mg has demonstrated cardiovascular benefits in persons with obesity and may be prioritized over other approved anti-obesity medications for the long-term treatment of obesity for most patients 1.

From the FDA Drug Label

The FDA drug label does not answer the question.

From the Research

Efficacy of Ozempic for Weight Loss in Obesity

• Ozempic (semaglutide) has been shown to be effective for weight loss in adults with overweight or obesity, with a mean change in body weight from baseline to week 68 of -14.9% in the semaglutide group compared to -2.4% with placebo 2.
• A study found that semaglutide 2.4 mg weekly produces an average weight loss of 15% at 1 year, which is significantly more than older medications approved for chronic weight management 3.
• Compared to liraglutide, semaglutide has been shown to result in significantly greater weight loss at 68 weeks, with a mean weight change from baseline of -15.8% with semaglutide vs -6.4% with liraglutide 4.

Comparison to Other Weight Loss Medications

• Semaglutide has been compared to other weight loss medications, including orlistat, phentermine, and liraglutide, and has been found to be one of the most effective options for weight loss 5, 4, 6.
• A network meta-analysis found that semaglutide, a GLP-1 receptor agonist, showed substantially larger benefits than other drugs with a similar risk of adverse events, with an odds ratio of 9.82 for weight loss of 5% or more and a mean difference of -11.40 in percentage body weight change 6.

Safety and Adverse Events

• The most common adverse events associated with semaglutide are nausea and diarrhea, which are typically transient and mild-to-moderate in severity and subside with time 2, 4.
• Gastrointestinal adverse events were reported by 84.1% of participants taking semaglutide and 82.7% of participants taking liraglutide in one study 4.