On November 8, 2023, Ozempic, Wegovy, and Mounjaro got company when the Food & Drug Administration approved Zepbound for individuals who are living with obesity or are overweight with at least one weight-related condition.
Zepbound is the latest in a class of drugs that can help patients lose significant weight, joining Ozempic, Wegovy, and Mounjaro.
While Zepbound and Mounjaro share the same generic drug name, tirzepatide, and are both produced by Eli Lilly, Mounjaro, is only FDA approved for patients with type 2 diabetes.
However, Ozempic, like Mounjaro, is only for patients with type 2 diabetes, while Wegovy can also be prescribed for the treatment of obesity and overweight with specific conditions. The drugs have made headlines, been referenced in popular culture, and become very popular.
One doctor says there’s a good reason for the interest.
“They work,” says Dr. Dina Peralta-Reich, MD, FAAP, FOMA, the director of New York Weight Wellness Medicine. “Finally, we have safe and highly effective medications available on the market for managing overweight and obesity.”
However, the buzz can create confusion and misinformation. Experts share that it is essential for patients to understand the facts to manage expectations, make informed decisions about their healthcare, and make positive changes to reach health and weight loss goals.
“Many of the weight loss medications have contraindications and various side effects, emphasizing the need for close medical supervision,” says Dr. Jihad Kudsi, MD, ABOM, MBA, MSF, FACS, an obesity medicine specialist and bariatric surgeon. “Additionally, not embracing healthier habits like a balanced diet and regular exercise can pose challenges for achieving lasting weight loss.”
To help, providers answered frequently asked questions about Zepbound.
Zepbound, or Tirzepatide, is an injectable medication approved by the FDA for the treatment of obesity and overweight with some conditions.
“It is a combination of two incretins, GLP-1, or Glucagon-like peptide-1, and GIP, or Gastric inhibitory polypeptide,” Peralta-Reich says.
Per the FDA approval, individuals are eligible for Zepbound if they:
“The medication is a weekly injection patients administer at home,” adds Matthew Tucker, PA-C, of Novant Health Salem Surgical Weight Loss. “The starting dose is 2.5mg weekly, and the dose can be increased monthly at intervals of 2.5mg up to a maximum dose of 15mg weekly. The maintenance dosages will be 5mg, 10mg, and 15mg.”
In a 2022-published trial of more than 2,500 adults, participants saw an average weight reduction of 15%, with patients reducing body weight by up to 22.5%. Another recent trial indicated an average weight loss of 26%.
One expert says the results are promising, but cautions patients should manage expectations.
“There’s no one-size-fits-all treatment for obesity,” says Dr. Katherine H. Saunders, MD, DABOM, the co-founder of Intellihealth and an Obesity Medicine physician at Weill Cornell Medicine. “Some individuals will be extremely successful with Zepbound while others might not lose much weight at all.”
Zepbound activates two hormone receptors, GIP (glucose-dependent insulinotropic polypeptide or gastric inhibitory polypeptide) and GLP-1 (glucagon-like peptide-1).
“Tirzepatide is a medication that imitates the actions of natural GIP and the GIP receptor,” Peralta-Reich says. “When combined with the GLP-1 receptor, it helps with insulin secretion and regulates glucose and lipid metabolism.”
Peralta-Reich explains that these hormones are secreted by the cells in the intestine. “After a person eats, these hormones are secreted by the cells in the intestines and start working.”
“They also slow down gastric emptying, which makes the person feel full for a longer period,” Peralta-Reich says. “This eventually leads to weight loss for individuals who struggle with chronic obesity.”
If the word “tirzepatide” sounds familiar, that’s because it is also the medication branded as Mounjaro, both of which are made by Eli Lilly.
How do they differ? Very little.
“They’re the same medication,” Peralta-Reich says. “The only difference is that Zepbound is FDA-approved for overweight with comorbidities and obesity, and Mounjaro has been approved for diabetes.”
Ozempic and Wegovy are brand names for the drug semaglutide.
Compared to the other GLP-1 receptor agonists like Wegovy, Zepbound is a dual agonist,” says Saunders. “It targets both GLP-1 and GIP versus Wegovy, which just targets GLP-1.”
Saunders says patients may report fewer side effects like GI discomfort from taking Tirzepatide versus Ozempic or Wegovy.
Though headlines recently pointed to a non-peer-reviewed study that indicated that patients taking tirzepatide lost more weight than those taking semaglutide, Tucker says it’s too soon to tell.
“There have been no direct head-to-head, peer-reviewed studies comparing the medications,” Tucker says.
Still, in the SURMOUNT-3 and SURMOUNT-4 trials, patients lost more using tirzepatide than participants in a trial for semaglutide— 26.7% versus 15%. However, the trials for semaglutide were shorter (68 weeks) than for tirzepatide (84 weeks).
Like semaglutide, tirzepatide is not a quick, short-term fix.
“Anti-obesity medications like Zepbound are not meant for short-term weight loss, but rather long-term treatment of obesity, which is a chronic disease,” Saunders says. Tirzepatide is meant for long-term use.
An Eli Lilly trial of more than 780 adults with obesity or who were overweight but did not have diabetes saw more significant weight loss if they took Zepbound for 88 weeks than those who stopped after 36 weeks.
Those who switched to the placebo regained some weight, though they still maintained a 9.5% weight loss.
Generally, yes. However, Kudsi emphasizes that patients should be aware of side effects and contraindications. He says the most common ones are GI-related and include:
Kudsi adds that people may experience increased lethargy, injection-site reactions, and hair loss.
More severe side effects may include:
Patients who have a familiar history of medullary thyroid carcinoma (MTC) or a history of Multiple Endocrine Neoplasia syndrome type 2 (MEN 2) are advised not to take the drug because of the chance it could cause thyroid tumors.
About $1,060, Saunders says. But how much of that a patient has to pay will vary.
“The cost can vary widely depending on insurance coverage,” Tucker says. “Patients need to check with their insurance providers to find out if Zepbound is covered by their plan.”
Patients have had difficulties getting coverage for anti-obesity medication Wegovy, with some plans even recently reducing coverage. Saunders hopes she’s wrong but predicts a similar issue with Zepbound.
“It’s my understanding that plans generally cover or don’t cover the whole class of anti-obesity medications, with a variety of rules and restrictions, so I anticipate that plans currently covering Wegovy will expand their anti-obesity medication armamentarium to include Zepbound as well,” Saunders says.
Zepbound showed tremendous promise in trials. However, patients in the trials also underwent lifestyle changes. Kudsi believes others taking Zepbound will see the best results in losing and maintaining weight if they adopt similar habits.
“A healthy lifestyle including healthy balanced diet and exercising is essential as part of a complete obesity treatment,” Kudsi says.
These modifications include:
“Lifestyle modifications play a crucial role in overall health, and relying solely on medication without addressing underlying lifestyle factors can limit the medication’s effectiveness,” Kudsi says.
Zepbound, a brand name for tirzepatide, was approved by the FDA for weight loss in November.
It is a dual-agonist drug that activates GIP (glucose-dependent insulinotropic polypeptide or gastric inhibitory polypeptide) and GLP-1 (glucagon-like peptide-1) hormone receptors, aiding in glucose management and helping patients feel fuller longer.
Numbers in trials vary. In later trials, patients lost an average of 26% body weight during 88 weeks, a higher percentage than patients taking semaglutide.
Zepbound may have fewer side effects, like GI discomfort, but patients may experience them.
Experts also say that lifestyle changes like diet and exercise can help patients lose and maintain weight more effectively than Zepbound alone.
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