FDA approves once-weekly semaglutide for weight loss
The FDA approved once-weekly semaglutide injection for chronic weight management in adults with obesity or with overweight and at least one weight-related condition, according to an agency press release.
Weekly semaglutide 2.4 mg (Wegovy, Novo Nordisk), a GLP-1 receptor agonist, is the first-approved drug for chronic weight management in adults with general obesity or overweight since 2014. Semaglutide is indicated for chronic weight management in adults with a BMI of 27 kg/m² or greater who have at least one weight-related comorbidity, such as type 2 diabetes or hypertension, or in adults with a BMI of at least 30 kg/m².
Semaglutide 1 mg injection (Ozempic) was first approved as a treatment for type 2 diabetes in 2017.
“Today’s approval offers adults with obesity or overweight a beneficial new treatment option to incorporate into a weight management program,” John Sharretts, MD, deputy director of the division of diabetes, lipid disorders and obesity in the FDA’s Center for Drug Evaluation and Research, said in the release. “FDA remains committed to facilitating the development and approval of additional safe and effective therapies for adults with obesity or overweight.”
Safety and efficacy of semaglutide 2.4 mg was assessed in four 68-week trials. Three were randomized, double-blind, placebo-controlled trials, including 16 weeks of dose increases, and one was a double-blind, placebo-controlled, randomized withdrawal trial in which patients assigned semaglutide either continued treatment or switched to a placebo. As Healio previously reported, in the STEP 1 study, published in The New England Journal of Medicine in February, adults with obesity assigned semaglutide 2.4 mg experienced substantial weight loss compared with placebo, with more than half of participants losing 15% of their body weight. Researchers found that mean change in body weight from baseline to week 68 was –14.9% for the semaglutide group vs. –2.4% for the placebo group (estimated treatment difference, –12.4 percentage points; 95% CI, –13.4 to –11.5). Those assigned semaglutide lost a mean –15.3 kg vs. –2.6 kg with placebo (estimated treatment difference, –12.7 kg; 95% CI, –13.7 to –11.7).
Follow-up data from the STEP 4 study, published in JAMA in March and also reported by Healio, demonstrated adults with obesity who continued semaglutide 2.4 mg beyond 20 weeks experienced continued weight loss or weight maintenance compared with adults who were switched to placebo. After randomization, the estimated mean weight change from week 20 to week 68 was –7.9% with continued semaglutide vs. a mean increase of 6.9% among participants switched to placebo (difference of –14.8 percentage points; 95% CI, –16 to –13.5). Compared with placebo, waist circumference decreased from week 20 to 68 (mean difference, –9.7 cm; 95% CI, –10.9 to –8.5), as did BMI (mean difference, –4.7; 95% CI, –5.2 to –4.3). Systolic BP remained stable during the maintenance phase for those assigned semaglutide and increased for those assigned placebo (difference, –3.9 mm Hg; 95% CI, –5.8 to –2). Physical function scores also improved in the semaglutide group vs. placebo.
Semaglutide must be increased gradually over 16 to 20 weeks to 2.4 mg once weekly to reduce gastrointestinal side effects, according to the FDA release.
Semaglutide 2.4 mg should not be used in combination with other semaglutide-containing products, other GLP-1 receptor agonists or other products intended for weight loss, including prescription drugs, over-the-counter drugs and herbal products, according to the release. Semaglutide 2.4 mg has not been studied in patients with a history of pancreatitis.
The most common side effects are nausea, diarrhea, vomiting, constipation, abdominal pain, headache, fatigue, dyspepsia, dizziness, abdominal distension, eructation, hypoglycemia in people with type 2 diabetes, flatulence, gastroenteritis and gastroesophageal reflux disease.
The prescribing information for semaglutide 2.4 mg contains a boxed warning to inform health care professionals and patients about the potential risk for thyroid C-cell tumors. Semaglutide should not be used in patients with a personal or family history of medullary thyroid carcinoma or in patients with multiple endocrine neoplasia syndrome type 2. Semaglutide also contains warnings for pancreatitis, gallbladder problems, hypoglycemia, acute kidney injury, diabetic retinopathy, increased heart rate and suicidal behavior or thinking. If semaglutide is used with insulin or a substance that causes insulin secretion, patients should speak with their provider about potentially lowering the dose of insulin or the insulin-inducing drug to reduce risk for hypoglycemia. FDA stated providers should monitor patients with kidney disease, diabetic retinopathy and depression or suicidal behaviors or thoughts.