- 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.
- In trials, patients lost an average of 26% body weight during 88 weeks, a higher percentage than patients taking semaglutide.
On November 8, 2023, the Food & Drug Administration approved a new medication named Zepbound for individuals living with obesity or those overweight with at least one weight-related condition. Zepbound joins a growing class of medications, including Ozempic, Wegovy, and Mounjaro, that assist patients in achieving significant weight loss.
Zepbound and Mounjaro both contain the same active ingredient, tirzepatide, and are manufactured by Eli Lilly. However, Mounjaro is currently only FDA-approved for patients with type 2 diabetes. Similarly, Ozempic is also designated for type 2 diabetes patients, while Wegovy is approved for treating obesity and overweight individuals with certain conditions. These drugs have gained widespread attention and popularity, even being referenced in popular culture.
Dr. Dina Peralta-Reich, MD, FAAP, FOMA, the director of New York Weight Wellness Medicine, highlights the effectiveness of these medications. “They work,” she states, underscoring the importance of having safe and effective options for managing overweight and obesity.
Despite the growing interest, there is a need for clarity and accurate information. Experts stress the importance of patients understanding the facts about these medications to set realistic expectations, make informed healthcare decisions, and achieve health and weight loss goals.
Dr. Jihad Kudsi, MD, ABOM, MBA, MSF, FACS, an obesity medicine specialist and bariatric surgeon, emphasizes the necessity of medical supervision due to potential contraindications and side effects of weight loss medications. He also points out that neglecting healthier lifestyle choices, such as a balanced diet and regular exercise, can impede sustained weight loss.
To address common queries and provide clarity, healthcare providers have been answering frequently asked questions about Zepbound.
What is Zepbound?
Zepbound, also known as Tirzepatide, is an injectable drug that has received FDA approval for use in treating obesity and overweight in individuals with certain conditions.
Dr. Dina Peralta-Reich explains that Zepbound works by combining two incretin hormones: GLP-1 (Glucagon-like peptide-1) and GIP (Gastric inhibitory polypeptide).
According to the criteria set by the FDA, patients are considered eligible for Zepbound treatment if they:
- Have a body mass index (BMI) of 30 kilograms per square meter (kg/m2) or more (obesity)
- Have a BMI of 27 kg/m2 or greater (overweight) with a minimum of one weight-related condition, like high blood pressure, type 2 diabetes, or high cholesterol
Matthew Tucker, PA-C, from Novant Health Salem Surgical Weight Loss, elaborates on the administration of Zepbound. “This medication is designed for patients to self-administer as a weekly injection at home,” he explains. “It begins with a starting dose of 2.5mg per week. This dose can be incrementally increased each month by 2.5mg, reaching up to a maximum weekly dose of 15mg. The maintenance doses for this medication are set at 5mg, 10mg, and 15mg.”
How much weight can someone who uses Zepbound lose?
In a clinical trial conducted in 2022, which involved over 2,500 adult participants, the average weight reduction observed was 15%, with some patients experiencing up to 22.5% body weight loss. Another more recent study reported an average weight loss of 26%.
Despite these promising outcomes, Dr. Katherine H. Saunders, MD, DABOM, co-founder of Intellihealth and an Obesity Medicine physician at Weill Cornell Medicine, advises a balanced perspective. She emphasizes that obesity treatment is not uniform for everyone. “There’s no one-size-fits-all treatment for obesity,” Dr. Saunders explains. “The response to Zepbound will vary among individuals; some may find great success with it, while others may not see substantial weight loss.”
How does Zepbound work?
Zepbound functions by activating two hormone receptors: GIP (glucose-dependent insulinotropic polypeptide, also known as gastric inhibitory polypeptide) and GLP-1 (glucagon-like peptide-1).
Dr. Dina Peralta-Reich elaborates on the mechanism of action for Tirzepatide, the active ingredient in Zepbound. “Tirzepatide mimics the actions of the natural GIP and its receptor,” she explains. “When it works in conjunction with the GLP-1 receptor, it aids in insulin secretion and plays a role in regulating glucose and lipid metabolism.”
She further explains the origin of these hormones, stating that they are released by the intestinal cells after eating. “These hormones become active post-meal, being secreted by the cells in the intestines.”
Dr. Peralta-Reich also highlights another aspect of how these hormones function. “They slow down gastric emptying, which helps a person feel full for an extended period,” she says. “This prolonged sensation of fullness can lead to weight loss, particularly in individuals dealing with chronic obesity.”
How is Zepbound different than Mounjaro?
The medication tirzepatide, recognized under the brand names Zepbound and Mounjaro, is produced by Eli Lilly. Despite their shared active ingredient, these medications have distinct approved uses.
Dr. Dina Peralta-Reich clarifies this distinction: “They’re the same medication in terms of composition.” The key difference lies in their FDA-approved applications. “Zepbound is approved for use in individuals who are overweight with comorbidities and those with obesity, while Mounjaro is specifically approved for the treatment of diabetes,” she explains.
How does Zepbound differ from Ozempic and Wegovy?
Ozempic and Wegovy are different brand names for the same drug, semaglutide.
Dr. Katherine H. Saunders highlights the distinct mechanism of Zepbound compared to these medications. “Zepbound is unique because it’s a dual agonist,” she explains. “Unlike Wegovy, which only targets the GLP-1 receptor, Zepbound targets both GLP-1 and GIP receptors.”
She also notes that patients on Tirzepatide, the active ingredient in Zepbound, may experience fewer side effects, particularly gastrointestinal discomfort, compared to those taking Ozempic or Wegovy.
Is Zepbound more effective than Ozempic and Wegovy?
Recent attention has been drawn to a non-peer-reviewed study suggesting that patients on tirzepatide, a component of Zepbound, might lose more weight compared to those on semaglutide, found in Ozempic and Wegovy. However, Matthew Tucker cautions that it may be premature to draw definitive conclusions.
“There have been no direct, head-to-head, peer-reviewed studies comparing these medications yet,” explains Tucker.
Nevertheless, in the SURMOUNT-3 and SURMOUNT-4 trials, participants using tirzepatide showed a higher average weight loss — 26.7%
How long does a person have to take Zepbound?
Dr. Katherine H. Saunders emphasizes that medications containing tirzepatide, like Zepbound, are not designed for quick, temporary weight loss solutions.
“Anti-obesity medications such as Zepbound are intended for the long-term management of obesity, a chronic condition,” she explains. This aligns with the notion that tirzepatide is meant for sustained, long-term use.
Supporting this, an Eli Lilly trial involving over 780 adults with obesity or overweight status (but without diabetes) demonstrated more significant weight loss in participants who continued Zepbound for 88 weeks compared to those who stopped at 36 weeks.
Interestingly, those who transitioned to a placebo after the initial period regained some weight but still maintained an average weight loss of 9.5%, indicating the drug’s lasting impact even after cessation.
Is Zebpound safe?
In general, sure. Kudsi does stress, though, that patients need to be informed about adverse effects and contraindications. According to him, GI-related ones predominate and comprise:
- Nausea
- Diarrhea
- Vomiting
- Constipation
- Stomach (abdominal) pain
- Indigestion
More severe side effects may include:
- Kidney problems
- Gallbladder problems
- Serious allergic reactions
- Low blood sugar
- Vision changes
- Depression or thoughts of suicide
Patients with a family history of medullary thyroid carcinoma (MTC) or who have a history of Multiple Endocrine Neoplasia syndrome type 2 (MEN 2) are recommended not to use this medication. This precaution is due to the potential risk of the drug inducing thyroid tumors in such individuals.
How much does Zepbound cost?
The cost of Zepbound is approximately $1,060, according to Dr. Katherine H. Saunders. However, the actual amount a patient might need to pay can differ significantly.
Matthew Tucker points out that the cost is highly dependent on insurance coverage. “The cost can vary widely depending on insurance coverage,” he says, advising patients to consult with their insurance providers to determine if Zepbound is included in their plan.
There have been challenges for patients in obtaining coverage for the anti-obesity medication Wegovy, with some insurance plans even recently scaling back coverage. Dr. Saunders expresses concern about potentially similar issues with Zepbound.
“It’s my understanding that insurance plans usually have a consistent policy regarding the entire class of anti-obesity medications, often with various rules and restrictions,” she explains. “So, I anticipate that plans which currently cover Wegovy will likely expand their coverage to include Zepbound as well.”
What other habits should people adopt for weight loss?
Zepbound demonstrated significant potential in clinical trials, but it’s important to note that participants in these trials also implemented lifestyle changes. Dr. Jihad Kudsi emphasizes that for individuals taking Zepbound, adopting similar habits is key to achieving optimal results in both losing and maintaining weight.
He stresses the importance of a holistic approach to obesity treatment. “A healthy lifestyle, which includes a healthy balanced diet and regular exercise, is essential as part of a complete obesity treatment,” Dr. Kudsi asserts. This underscores that while Zepbound can be effective, its full potential is best realized when combined with healthy lifestyle choices.
These modifications include:
- Logging 150 minutes of moderate-intensity aerobic exercise weekly, such as biking or brisk walking
- Strength training at least twice per week
- Eating a balanced diet full of lean proteins and leafy greens
“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.
Takeaway
Zepbound, the commercial name for tirzepatide, received FDA approval for weight loss in November. This medication functions as a dual-agonist, targeting both GIP (glucose-dependent insulinotropic polypeptide, also known as gastric inhibitory polypeptide) and GLP-1 (glucagon-like peptide-1) receptors. By doing so, it assists in glucose regulation and extends the feeling of fullness in patients.
Clinical trial results for Zepbound have shown variability. In more recent studies, participants experienced an average weight loss of 26% over 88 weeks, surpassing the weight loss percentages observed in patients using semaglutide.
While Zepbound may present fewer side effects such as gastrointestinal discomfort, it’s still possible for patients to experience them. Experts underscore the importance of incorporating lifestyle modifications, including diet and exercise, to enhance weight loss and maintenance outcomes, rather than relying solely on Zepbound for these results.
