What’s the difference between Mounjaro and Zepbound?

In the United Kingdom, tirzepatide has only name - “Mounjaro” - and it’s prescribed for the treatment of weight loss and diabetes. But in the US the same drug is named “Zepbound” for weight loss and “Mounjaro” for diabetes. Two different names for the same weight loss drug? If this sounds familiar, it’s because it is. For Mounjaro and Zepbound read Ozempic and Wegovy. What are these drugs and why do they have different names?

In the UK you only need to remember one word: “Mounjaro”

If you need to remember just one thing it is that in the UK there is only one version of Eli Lilly’s blockbuster drug, Tirzepatide. And that’s Mounjaro.

It will soon be available in the UK for sale through private companies, such as CheqUp, for the treatment of weight loss and diabetes, and is available for the treatment of diabetes on the NHS.

However, given the crossover in media between the UK and the United States, it’s worth understanding that tirzepatide for weight loss has a different name in the US.

So, why the confusion between Mounjaro and Zepbound?

Simply, Zepbound and Mounjaro are two brand names which refer to the same drug, tirzepatide. This targets GLP-1, or glucagon-like peptide-1, a hormone that plays a crucial role in regulating blood sugar levels and appetite. By mimicking the action of GLP-1, these drugs not only help lower blood sugar levels in people with diabetes but also contribute to weight loss by reducing appetite and food intake.

In the United States and other countries, tirzepatide is known as “Zepbound” for the treatment of weight management and “Mounjaro” for the treatment of diabetes.

Diabetes management

From a diabetes management standpoint, Mounjaro has shown promise in helping patients achieve better glycemic control. Clinical trials have highlighted its effectiveness in lowering A1C levels, a key indicator of blood sugar management over time. Patients using Mounjaro for their diabetes treatment have also reported an added benefit of weight loss, making it an attractive option for those looking to manage both their diabetes and weight.

Weight management

On the flip side, Zepbound, much like Wegovy derived from Ozempic, is positioned in the market primarily as a weight management solution. Despite being pharmacologically identical to Mounjaro, Zepbound is dosed and marketed differently, focusing on its capacity to aid in significant weight reduction. Clinical trials supporting Zepbound’s approval for weight management showcased substantial weight loss in participants, further cementing GLP-1 receptor agonists' role in obesity treatment.

The comparison to Ozempic and Wegovy

The parallel between Zepbound/Mounjaro and Ozempic/Wegovy is striking. Ozempic, initially approved for managing diabetes, shares the same active ingredient as Wegovy, which is approved for weight management. The key difference lies in the dosing and the target audience, with Wegovy being prescribed at higher doses specifically for those looking to lose weight. This strategic bifurcation allows pharmaceutical companies to address two burgeoning health crises with a single molecule, maximizing the therapeutic potential of their discovery.

Mounjaro vs Wegovy Graph

Mounjaro - up to 26% weight loss in clinical trials

Clinical trials have been pivotal in demonstrating the efficacy of these medications. For instance, Mounjaro's phase 3 trials for diabetes management showed not only significant reductions in A1C levels but also noted weight loss as a side effect. Similarly, trials for Zepbound in the context of weight management have reported average weight losses of up to 26% of body weight in patients, offering a new hope for individuals struggling with weight issues.

Other medical benefits

Research continues to unveil other potential benefits of GLP-1 receptor agonists, including cardiovascular health improvements and a possible reduction in the risk of major adverse cardiovascular events. Such findings are encouraging, suggesting that Zepbound and Mounjaro could have a multifaceted impact on patient health beyond their primary indications.

The future of diabetes and weight management

The dual use of Zepbound and Mounjaro, much like Ozempic and Wegovy, represents a growing trend in the pharmaceutical industry: repurposing and rebranding medications to serve multiple patient needs. This approach not only maximizes the utility of a single drug but also offers patients comprehensive treatment options that tackle multiple aspects of their health.

As the medical community continues to explore the full potential of GLP-1 receptor agonists, it’s clear that drugs like Zepbound and Mounjaro could play a crucial role in the future of diabetes and weight management. With ongoing research and development, the possibilities for improving patient outcomes in these areas are both promising and exciting.

Published: 14 February 2024