What you need to know about Zepbound, the new weight loss drug

The Food and Drug Administration’s decision Wednesday to approve the weight-loss drug tirzepatide adds a powerful new tool to the rapidly growing arsenal of obesity drugs.

The drug, which will bear the brand name Zepbound, contains the same compound in the sought-after diabetes drug Mounjaro. Many people have used Mounjaro off-label for weight loss since it was first approved in May 2022, but this move could pave the way for insurance coverage and open the floodgates for more prescriptions.

Zepbound is the second drug in a new class of anti-obesity drugs approved for weight loss after Wegovy. And it’s now probably the most effective treatment to combat obesity besides bariatric surgery, said Dr. Scott Hagan, assistant professor of medicine at the University of Washington. But for many, Mounjaro has been hard to find in the year since it came on the market.

“It’s very similar to what we experienced with Ozempic,” said Dr. Andrew Kraftson, a clinical associate professor in the department of metabolism, endocrinology and diabetes at Michigan Medicine, noted that demand for weight-loss drugs has reached a “heavy pitch.” Now, he said, patients will likely clamor for this new drug. Here’s what you need to know.

Who is eligible for Zepbound?

The FDA has approved Zepbound for people with a body mass index — a much-criticized measure — of 30 or higher, which technically qualifies them as obese, or for people with a BMI of 27 who also have certain weight-related conditions, such as high blood pressure. Regulators said the drug should be used in combination with a reduced-calorie diet and increased physical activity.

How does tirzepatide work for weight loss?

Zepbound, made by Eli Lilly, is the brand name for tirzepatide when used for weight loss. When the drug is prescribed for diabetes, it is sold under the brand name Mounjaro.

Like semaglutide, the compound in Ozempic and Wegovy, tirzepatide slows stomach emptying. People feel fuller, faster and longer. All three medications too target the area of ​​the brain that regulates appetite, curbing cravings for many people.

Semaglutide simulates a single hormone in the body, while tirzepatide mimics two, which experts say may be why it is often more effective at causing weight loss. In a 72 week clinical trialfunded by Eli Lilly, Obese participants taking the highest dose of tirzepatide lost an average of about 18 percent of their body weight.

If I’m already using Ozempic or Wegovy, should I switch?

Not everyone responds to these drugs the same way: someone might lose little to no weight with semaglutide, but lose pounds with tirzepatide, and vice versa, said Dr. Janice Jin Hwang, department head of endocrinology and metabolism at North University. Carolina School of Medicine. People whose weight loss may be most closely linked to other health outcomes – such as those at risk for heart failure or liver disease – may benefit more from losing a significant amount of weight with a drug like Zepbound.

But some people may lose too much weight by taking these medications, Dr. warned. Hwang. Older people in particular should take their weight loss into account, as this can lead to shrinking muscle mass. Doctors must weigh the risks and benefits for each patient, she said.

“There are no guidelines for any of this,” she said. “We just try to think about the patient holistically.”

Will insurance cover this and what will it likely cost out of pocket?

Coverage may vary from plan to plan, but some insurance companies will likely cover it for those who meet the FDA’s criteria. Eli Lilly said in a press release that it expects Zepbound to be available in the US by the end of the year at a list price of $1,059.87.

What are the side effects?

In an Eli Lilly-funded study of tirzepatide for obesity, gastrointestinal problems were the most common side effects. About a third of participants taking the highest dose of tirzepatide experienced nausea and about a fifth of participants experienced diarrhea. Some participants also reported abdominal pain, vomiting, constipation, headaches and dizziness. According to the FDA approval, people who use Zepbound may also experience acid reflux, hair loss, and gastroesophageal reflux disease.

Because tirzepatide is so new, we don’t know much yet about its long-term effects, Dr. Hwang said. And people who take these types of drugs to lose weight are typically advised to continue taking them for the rest of their lives, she said.