Liraglutide
Brand: Victoza, Saxenda
A once-daily GLP-1 receptor agonist and one of the most studied incretin drugs — FDA-approved for type 2 diabetes (Victoza), chronic weight management (Saxenda), and cardiovascular risk reduction.
Victoza (type 2 diabetes, 2010) and Saxenda (obesity, 2014) are FDA-approved. The two brands are the same molecule at different maximum doses; a generic liraglutide is also now available.
What it is
Liraglutide is a GLP-1 receptor agonist — a modified version of the human GLP-1 hormone engineered to resist rapid breakdown, giving it a roughly 13-hour half-life. That is long enough for once-daily injection but short of the once-weekly dosing of newer agents. It was the first daily GLP-1 drug to be approved for both diabetes and obesity, and it carries one of the longest real-world track records in the class.
What it’s approved or studied for
Liraglutide is FDA-approved for type 2 diabetes at up to 1.8 mg/day (Victoza), chronic weight management at up to 3.0 mg/day (Saxenda), and cardiovascular risk reduction in adults with type 2 diabetes and established or high cardiovascular risk. Victoza and Saxenda are the same molecule branded and dosed differently.
What human evidence exists
The evidence base is large and mature. The LEAD program established glycemic benefit; the SCALE program established weight-management benefit (about 8% at 56 weeks on 3.0 mg); and the LEADER outcomes trial (2016) demonstrated a 13% reduction in major cardiovascular events in high-risk diabetes. These are Grade A outcomes. The honest caveat is magnitude: liraglutide’s weight loss is real but noticeably smaller than semaglutide’s or tirzepatide’s, and it requires a daily rather than weekly injection.
The major unknowns
The main open questions are practical rather than existential: daily dosing reduces convenience and adherence versus weekly agents, weight regain after stopping mirrors the rest of the class, and — as with all rapid weight loss — a share of the loss is lean tissue unless training and protein intake are managed.
Most important safety considerations
Gastrointestinal side effects are common and ease with slow dose titration. Liraglutide carries the class boxed warning for thyroid C-cell tumors, based on rodent data; a personal or family history of medullary thyroid carcinoma or MEN 2 is a contraindication. Pancreatitis and gallbladder disease are uncommon but recognized risks. This page is a research summary, not medical advice — discuss any GLP-1 therapy with a clinician.
Evidence by outcome
Each outcome is graded on its own evidence — a compound can be strong for one use and unproven for another. See how we grade.
Approved and repeatedly proven to lower HbA1c. — The LEAD program established consistent, clinically meaningful HbA1c reductions versus placebo and active comparators, underpinning the 2010 Victoza approval.
Reduces major cardiovascular events in high-risk type 2 diabetes. — LEADER (NEJM 2016) randomized 9,340 people with type 2 diabetes at high cardiovascular risk and showed a 13% relative reduction in major adverse cardiovascular events (HR 0.87), leading to an FDA cardiovascular indication.
Approved for obesity; effect is real but more modest than newer agents. — The SCALE program (NEJM 2015) reported roughly 8% mean body-weight loss on 3.0 mg at 56 weeks versus about 2.6% with placebo — clinically meaningful, but below the ~15–21% seen with semaglutide and tirzepatide.
Not a benefit — some lean mass is lost with fat.
Safety
Common adverse effects
- Nausea
- Vomiting
- Diarrhea
- Constipation
- Headache
Serious risks
- Pancreatitis (uncommon)
- Gallbladder disease
- Thyroid C-cell tumors (seen in rodents; boxed warning)
- Acute kidney injury with dehydration
Contraindications
- Personal or family history of medullary thyroid carcinoma
- Multiple endocrine neoplasia syndrome type 2
- Known hypersensitivity to liraglutide
References