Liraglutide
Also known as: Victoza, Saxenda, NN2211
Overview
Clinical Summary
Liraglutide is a once-daily GLP-1 receptor agonist approved for type 2 diabetes (Victoza, 1.2 and 1.8 mg) and chronic weight management (Saxenda, 3.0 mg). It was the first GLP-1RA to receive an obesity indication and the first to demonstrate cardiovascular benefit in a dedicated outcomes trial. Liraglutide is a human GLP-1 analogue with 97% sequence homology to native GLP-1, modified with a C-16 fatty acid (palmitic acid) side chain that promotes albumin binding and extends the half-life to approximately 13 hours. While it has been largely superseded by once-weekly agents for new prescriptions, it remains an important option particularly for patients who prefer a daily dosing regimen that allows more flexible titration.
Plain Language Summary
Liraglutide is a daily injectable medication that mimics the natural hormone GLP-1 to help control blood sugar and appetite. It is available as Victoza for type 2 diabetes and Saxenda for weight management. It was the first GLP-1 medication approved specifically for weight loss. In clinical trials, people taking Saxenda lost an average of about 8% of their body weight. It was also proven to reduce the risk of major cardiovascular events like heart attacks in people with type 2 diabetes. It has since been joined by more potent weekly options, but remains a well-established treatment with extensive long-term safety data.
Mechanism of Action
Liraglutide activates the GLP-1 receptor, a class B G-protein-coupled receptor, with effects across multiple organ systems. Pancreatic effects include enhanced glucose-dependent insulin secretion, suppression of inappropriate glucagon release, and possible beta-cell preservation (demonstrated in preclinical models). Central nervous system effects include activation of appetite-regulating neurons in the hypothalamus and brainstem, leading to reduced caloric intake. Gastrointestinal effects include delayed gastric emptying, which contributes to postprandial glucose control and satiety. The palmitic acid acylation enables noncovalent albumin binding, providing DPP-4 resistance and a half-life of approximately 13 hours, suitable for once-daily subcutaneous injection.
Evidence Summary
The LEAD program (6 Phase 3 trials) established liraglutide for T2D, with HbA1c reductions of 1.0 to 1.5% and modest weight loss. LEADER (n=9,340, median 3.8 years) demonstrated a 13% reduction in MACE (HR 0.87, 95% CI 0.78-0.97) and 15% reduction in all-cause mortality in T2D patients at high cardiovascular risk. The SCALE program evaluated liraglutide 3.0 mg for obesity: SCALE Obesity and Prediabetes (n=3,731) showed 8.0% mean weight loss vs 2.6% placebo at 56 weeks. SCALE Diabetes showed 6.0% weight loss in T2D patients. Limitations include the inferior weight loss compared to semaglutide and tirzepatide, daily injection burden, and high nausea rates during initiation.
Safety Profile
The safety profile has been characterized over more than 15 years of clinical use. Gastrointestinal adverse events are most common: nausea (approximately 39% with 3.0 mg dose), diarrhea, constipation, and vomiting, predominantly during dose escalation. The FDA label carries a boxed warning for thyroid C-cell tumors. Acute pancreatitis occurs rarely (0.2-0.4%). The LEADER trial did not show excess MTC in humans over 3.8 years. Cholelithiasis rates increase with the weight management dose. Mean heart rate increases of 2 to 3 bpm are observed. Liraglutide 3.0 mg (Saxenda) is not recommended for use with other GLP-1RAs including Victoza.
Contraindications
- Personal or family history of medullary thyroid carcinoma
- Multiple endocrine neoplasia type 2 (MEN2)
- Known hypersensitivity to liraglutide or any product components
- Pregnancy (category X for Saxenda)
Adverse Events
- Nausea (most common, up to 39% at 3.0 mg dose)
- Diarrhea
- Constipation
- Vomiting
- Headache
- Decreased appetite
- Injection site reactions
Interactions
- Delays gastric emptying; may affect rate and extent of absorption of concomitant oral medications
- Increased risk of hypoglycemia with insulin or sulfonylureas; consider reducing doses of these agents
- Should not be used concomitantly with other GLP-1RA products
- Caution with oral medications that have narrow therapeutic windows
Active Safety Signals
Liraglutide carries a boxed warning for thyroid C-cell tumors based on rodent findings. The LEADER trial did not show an increased signal for MTC in humans over 3.8 years, but long-term surveillance continues. Contraindicated in patients with MTC history or MEN2.
Regulatory Notes
Victoza (liraglutide 1.2 and 1.8 mg) was FDA-approved in January 2010 for T2D. Saxenda (liraglutide 3.0 mg) was approved in December 2014 for chronic weight management. Saxenda was the first GLP-1RA approved for obesity. In 2020, Saxenda received an expanded indication for adolescents aged 12 and older with obesity. Both products are manufactured by Novo Nordisk. Generic/biosimilar competition is anticipated as liraglutide patents expire.
Monitoring Considerations
Monitor HbA1c, fasting glucose, and body weight. Titrate gradually over 4 to 5 weeks (starting at 0.6 mg, increasing by 0.6 mg weekly to target dose) to improve GI tolerability. Monitor for signs of pancreatitis. Lipase and amylase elevations may occur without clinical pancreatitis. Assess heart rate periodically. In patients not achieving meaningful weight loss (at least 4% at 16 weeks on Saxenda), consider discontinuation as response at 16 weeks is predictive of long-term outcome. Calcitonin monitoring is not specifically required but should be considered if clinically indicated.
These are general considerations for clinical awareness and do not constitute prescriptive monitoring recommendations for any individual patient.
Stability and Handling Notes
Store refrigerated at 2 to 8 degrees C prior to first use. After first use, the pen can be stored at room temperature (up to 30 degrees C) or refrigerated and must be used within 30 days. Protect from light and heat. Do not freeze; discard if frozen. The pen uses disposable needles that must be removed after each injection to prevent air bubbles and leakage.
References
- 1RCT
Liraglutide and Cardiovascular Outcomes in Type 2 Diabetes (LEADER)
Marso SP, Daniels GH, Tanaka K, et al. (2016). New England Journal of Medicine
Key findings: Cardiovascular outcomes trial in 9,340 T2D patients at high CV risk. Liraglutide reduced MACE by 13% (HR 0.87, 95% CI 0.78-0.97) and all-cause mortality by 15% over a median 3.8-year follow-up.
Limitations: Modest effect size. Benefit driven primarily by CV death rather than MI or stroke.
View source - 2RCT
A Randomized, Controlled Trial of 3.0 mg of Liraglutide in Weight Management (SCALE Obesity and Prediabetes)
Pi-Sunyer X, Astrup A, Fujioka K, et al. (2015). New England Journal of Medicine
Key findings: Phase 3 trial in 3,731 adults with obesity or overweight. Liraglutide 3.0 mg daily produced 8.0% mean weight loss vs 2.6% placebo at 56 weeks. 63.2% of patients achieved at least 5% weight loss.
Limitations: Daily injection burden. Weight loss inferior to newer GLP-1RAs such as semaglutide.
View source - 3FDA label
SAXENDA (liraglutide [rDNA origin]) injection Prescribing Information
Novo Nordisk Inc. (2023). FDA
Key findings: Full prescribing information including boxed warning for thyroid C-cell tumors, indication for chronic weight management, dosing (0.6 mg titration to 3.0 mg daily), contraindications, and clinical trial data.
Limitations: Label information; not primary research.
View source - 4review
Liraglutide: A Review of Its Use in the Management of Type 2 Diabetes Mellitus
Scott LJ. (2014). Drugs
Key findings: Comprehensive review of liraglutide pharmacology, clinical efficacy, and safety across the T2D indication. Summarizes data from the LEAD trial program.
Limitations: Narrative review predating obesity indication and LEADER results.
Last reviewed: 2026-03-24 | Version: 1 | Status: Published