What Is Liraglutide?
Liraglutide is a synthetic GLP-1 receptor agonist that mimics the body’s natural incretin hormone to regulate appetite, insulin secretion, and blood glucose levels. It is marketed under two different brand names for two distinct purposes:
- Victoza: Approved for type 2 diabetes and cardiovascular risk reduction
- Saxenda: Approved specifically for chronic weight management in individuals with obesity or overweight with comorbidities
Mechanism of Action
Liraglutide acts by binding to GLP-1 receptors to:
- Enhance glucose-dependent insulin secretion
- Suppress inappropriate glucagon release after meals
- Slow gastric emptying, increasing satiety
- Reduce appetite, leading to decreased calorie intake
Indications
- Victoza: For adults and children ≥10 years with type 2 diabetes
- Saxenda: For adults with BMI ≥30 or BMI ≥27 with comorbidities (e.g., hypertension, dyslipidemia)
- Saxenda is also approved for adolescents aged 12–17 with obesity (BMI ≥95th percentile)
Dosage & Administration
- Victoza: Subcutaneous injection once daily, starting at 0.6 mg and titrated up to 1.8 mg
- Saxenda: Subcutaneous injection once daily, starting at 0.6 mg and titrated weekly to 3.0 mg
Benefits
- Improves blood glucose control (Victoza)
- Reduces major cardiovascular events in people with type 2 diabetes (Victoza)
- Promotes 5–10% body weight loss on average (Saxenda)
- Supports appetite reduction and long-term weight management
Side Effects
- Nausea (most common, especially during dose escalation)
- Vomiting or diarrhea
- Headache, dizziness, fatigue
- Hypoglycemia (more likely when used with insulin or sulfonylureas)
- Rare: pancreatitis, gallbladder disease, thyroid C-cell tumors (animal studies)
Contraindications & Warnings
- History of medullary thyroid carcinoma (MTC)
- Multiple Endocrine Neoplasia syndrome type 2 (MEN 2)
- Severe gastrointestinal disease
- Use caution in patients with renal impairment or history of pancreatitis
Victoza vs. Saxenda
| Feature | Victoza | Saxenda |
|---|---|---|
| Indication | Type 2 Diabetes | Weight Management |
| Dose Range | 0.6–1.8 mg daily | 0.6–3.0 mg daily |
| Population | Adults and children ≥10 with T2D | Adults and teens ≥12 with obesity |
| Cardiovascular Benefit | Yes (LEADER trial) | No specific CV indication |
Clinical Evidence
- LEADER Trial (2016): Victoza reduced the risk of major cardiovascular events by 13% in patients with T2D and high CV risk.
- SCALE Trials: Saxenda led to significantly greater weight loss compared to placebo (8–10% vs. 2–3%) over 56 weeks.
Cost & Insurance
- Victoza often covered under diabetes plans; Saxenda may require prior authorization for weight loss
- Patient savings cards may be available from the manufacturer
Summary
Liraglutide is a versatile GLP-1 therapy with strong efficacy for both diabetes and weight management. The choice between Victoza and Saxenda depends on the primary goal—glucose control vs. weight loss—and clinical context.
References
- Marso SP, et al. “Liraglutide and Cardiovascular Outcomes in Type 2 Diabetes.” NEJM. 2016.
- Pi-Sunyer X, et al. “A Randomized Trial of Liraglutide for Weight Loss.” NEJM. 2015.
- FDA Prescribing Information: Victoza & Saxenda. Updated 2024.
- American Diabetes Association. “Pharmacologic Approaches to Glycemic Treatment.” Diabetes Care. 2024.