Semaglutide vs liraglutide: the new GLP-1 vs the original, compared
Liraglutide (Saxenda / Victoza) was the first GLP-1 approved for obesity. Semaglutide surpassed it on every dimension that matters. Here's why, and when liraglutide still makes sense.
Liraglutide was FDA approved as Victoza (type 2 diabetes, 2010) and Saxenda (chronic weight management, 2014). Until semaglutide's 2017 approval, it was the only GLP-1 approved for obesity. Semaglutide then outperformed liraglutide on efficacy, dosing convenience, and patient preference in head-to-head trials. Today, liraglutide is a legacy drug — still prescribed in specific scenarios, but rarely the first-line choice.
| Field | Semaglutide | Liraglutide |
|---|---|---|
| Brand names | Ozempic, Wegovy, Rybelsus | Victoza, Saxenda |
| Manufacturer | Novo Nordisk | Novo Nordisk |
| FDA approved | 2017 (T2D), 2021 (obesity) | 2010 (T2D), 2014 (obesity) |
| Indication | T2D, chronic weight management, CV risk reduction | T2D, chronic weight management; adolescent obesity (age 12+, Saxenda) |
| Mechanism | GLP-1 receptor agonist (single pathway) | GLP-1 receptor agonist (shorter half-life) |
| Delivery | Once-weekly subcutaneous injection (oral T2D form also) | Daily subcutaneous injection |
| Avg weight loss | ~14.9% at 68 weeks (STEP-1, 2.4 mg) | ~8% at 56 weeks (SCALE, 3.0 mg) |
Primary sources
- Semaglutide: STEP-1 (NEJM, 2021)
- Liraglutide: SUSTAIN-10 head-to-head (Diabetes Care, 2019)
Frequently asked
Is semaglutide just a better version of liraglutide?
Essentially, yes. Both are GLP-1 receptor agonists from Novo Nordisk. Semaglutide has a longer half-life (weekly vs daily dosing), produces meaningfully larger mean weight loss at labeled maximum doses, and has better cardiovascular outcomes data (SELECT vs LEADER).
When would a clinician still pick liraglutide?
When insurance covers Saxenda but not Wegovy (some plans). When a shorter half-life is clinically preferred (easier to discontinue if adverse events appear). For adolescents age 12+, Saxenda has a dedicated approval; Wegovy's adolescent approval is also available now.
Is generic liraglutide available?
Generic approvals for liraglutide started arriving in 2024-2025 as patents expired, which lowers cost. Generic semaglutide is still years away. Cost sensitivity can make liraglutide attractive for insurance-excluded patients.