With all the excitement about GLP-1 agonists,
Of course, we want to make sure that we’re treating the right condition. If the patient has type 2 diabetes, we tend to give them medication that is indicated for type 2 diabetes. Many GLP-1 agonists are available in a diabetes version and a chronic weight management or obesity version. If a patient has diabetes and obesity, they can receive either one. If a patient has only diabetes but not obesity, they should be prescribed the diabetes version. For obesity without diabetes, we tend to stick with the drugs that are indicated for chronic weight management.
Let’s go through them.
Exenatide. In chronological order of approval, the first GLP-1 drug that was used for diabetes dates back to exenatide (Bydureon). Bydureon had a partner called Byetta (also exenatide), both of which are still on the market but infrequently used. Some patients reported that these medications were inconvenient because they required twice-daily injections and caused painful injection-site nodules.
Diabetes drugs in more common use include liraglutide (Victoza) for type 2 diabetes. It is a daily injection and has various doses. We always start low and increase with tolerance and desired effect for A1c.
Liraglutide. Victoza has an antiobesity counterpart called Saxenda. The Saxenda pen looks very similar to the Victoza pen. It is a daily GLP-1 agonist for chronic weight management. The SCALE trial demonstrated 8%-12% weight loss with Saxenda.
Those are the daily injections: Victoza for diabetes and Saxenda for weight loss.
Our patients are very excited about the advent of weekly injections for diabetes and weight management. Ozempic is very popular. It is a weekly GLP-1 agonist for type 2 diabetes. Many patients come in asking for Ozempic, and we must make sure that we’re moving them in the right direction depending on their condition.
Semaglutide. Ozempic has a few different doses. It is a weekly injection and has been found to be quite efficacious for treating diabetes. The drug’s weight loss counterpart is called Wegovy, which comes in a different pen. Both forms contain the compound semaglutide. While all of these GLP-1 agonists are indicated to treat type 2 diabetes or for weight management, Wegovy has a special indication that none of the others have. In March 2024, Wegovy acquired an indication to decrease cardiac risk in those with a BMI ≥ 27 and a previous cardiac history. This will really change the accessibility of this medication because patients with heart conditions who are on Medicare are expected to have access to Wegovy.
Tirzepatide. Another weekly injection for treatment of type 2 diabetes is called Mounjaro. Its counterpart for weight management is called Zepbound, which was found to have about 20.9% weight loss over 72 weeks. These medications have similar side effects in differing degrees, but the most-often reported are nausea, stool changes, abdominal pain, and reflux. There are some other potential side effects; I recommend that you read the individual prescribing information available for each drug to have more clarity about that.
It is important that we stay on label for using the GLP-1 receptor agonists, for many reasons. One, it increases our patients’ accessibility to the right medication for them, and we can also make sure that we’re treating the patient with the right drug according to the clinical trials. When the clinical trials are done, the study populations demonstrate safety and efficacy for that population. But if we’re prescribing a GLP-1 for a different population, it is considered off-label use.
Dr. Lofton, an obesity medicine specialist, is clinical associate professor of surgery and medicine at NYU Grossman School of Medicine, and director of the medical weight management program at NYU Langone Weight Management Center, New York. She disclosed ties to Novo Nordisk and Eli Lilly. This transcript has been edited for clarity.
A version of this article appeared on Medscape.com.