Saxenda becomes the first US-approved GLP-1 for weight management

Saxenda, a once-daily injection of liraglutide at a 3-mg dose, has reached the US market as the first GLP-1 receptor agonist approved for chronic weight management. The FDA's National Drug Code directory lists the product with a marketing start date of Dec. 31, 2014, under application number NDA 206321 ^[1].

The listing describes the drug as liraglutide at 6 mg/mL in 3-mL plastic syringes, supplied five to a carton for subcutaneous use, and attributes the record to A-S Medication Solutions, a distributor operating under the same application number ^[1]. Liraglutide is the molecule Novo Nordisk has marketed since 2010 as Victoza for type 2 diabetes at doses up to 1.8 mg a day, according to the same directory ^[1]. Researchers describe liraglutide as a glucagon-like peptide-1 analog whose weight effect grows with dose up to 3.0 mg and comes mainly from eating less rather than burning more energy ^[2].

The SCALE trial behind the approval

The data supporting the new use come from a 56-week, double-blind, placebo-controlled trial run at 191 sites in 27 countries between June 1, 2011, and March 18, 2013 ^[2]. Investigators enrolled 3,731 adults without type 2 diabetes whose body-mass index was 30 or higher, or 27 or higher if they also had treated or untreated dyslipidemia or high blood pressure ^[2]. Participants were randomly split 2:1 into liraglutide 3.0 mg (2,487 people) or placebo (1,244), and both groups received counseling on lifestyle changes ^[2].

At entry, the group averaged 45.1 years of age, 106.2 kg in weight and a BMI of 38.3; 78.5% were women and 61.2% had prediabetes ^[2]. By week 56, the liraglutide arm had dropped a mean of 8.4 kg and the placebo arm 2.8 kg, a gap of 5.6 kg (95% confidence interval, −6.0 to −5.1; P<0.001) ^[2]. Among those on the drug, 63.2% shed at least 5% of their starting weight, compared with 27.1% on placebo; 33.1% and 10.6%, respectively, lost more than 10% ^[2]. Nausea and diarrhea, usually mild or moderate, were the most frequently reported problems, and serious events affected 6.2% of the liraglutide group versus 5.0% of the placebo group ^[2]. In all, 71.9% of the drug group and 64.4% of the placebo group stayed through all 56 weeks ^[2].

People with type 1 or type 2 diabetes were not enrolled, and neither were those with a history of pancreatitis, previous bariatric surgery, a major depressive or other severe psychiatric disorder, or a family or personal history of multiple endocrine neoplasia type 2 or familial medullary thyroid carcinoma ^[2].

Why it matters for patients

Until now the molecule was sold in the US only for blood sugar control in type 2 diabetes, at doses below the weight-management strength ^[1][2]. Saxenda targets a different group: adults with obesity, or with a BMI of at least 27 plus a weight-related condition such as dyslipidemia or hypertension, who do not have diabetes ^[2]. The trials studied that population, so the results say nothing about people outside those criteria.

Every participant also received diet and exercise counseling, so the reported losses reflect the drug added to that support rather than the drug by itself ^[2]. Averages also hide a wide spread: weight change in the liraglutide group carried a standard deviation of 7.3 kg, meaning individual results landed well above and below 8.4 kg ^[2]. And the drug is a daily injection, not a tablet ^[1].

US pricing, insurance coverage and launch supply have not been disclosed ^[1].

What happens next

A two-year extension of the trial, focused on participants with prediabetes, had just been completed when the main results appeared; it was designed to test whether liraglutide delays the onset of type 2 diabetes ^[2]. No outcome from that extension appears in the main publication ^[2]. The current Saxenda listing carries an expiration date of Dec. 31, 2026 ^[1].