Ozempic’s rise to mainstream fame may be unprecedented for a diabetes drug — the medication provokes such powerful weight loss that it has caused a frenzy both inside and outside of the diabetes community, leading to widespread shortages. But Ozempic may soon be surpassed by a different drug that sparks even greater weight loss: Mounjaro.
Tirzepatide (Mounjaro) was first approved last year for patients with type 2 diabetes, and though it has comparatively flown under the radar, the drug appears to be even more powerful than Ozempic. It is arguably the most effective type 2 diabetes drug ever developed, granting jaw-dropping blood sugar improvements in tandem with impressive weight loss.
And though it has not yet been approved for use as an obesity treatment, eager patients without diabetes are increasingly asking their doctors for access to the injection, as recently reported by The New York Times. Mounjaro may well be the next great fad in weight loss medicine — and it’s already causing problems for the people with diabetes that have come to rely on it.
Mounjaro and Weight Loss
As earlier reported by our friends at diaTribe, many large clinical trials have shown that Mounjaro leads to impressive weight loss for patients with type 2 diabetes. In four arms of the pivotal SURPASS trials, each of which tested the drug in slightly different populations, Mounjaro led to an average of 13.7 to 29 pounds of weight loss.
The numbers are even more impressive in people without diabetes. In the SURMOUNT trial, the drug helped adults lose 22.5% of their body weight in 72 weeks, an extraordinary result on par with bariatric surgery. Some participants on the heaviest dose of Mounjaro lost over 50 pounds. Even at its lowest dosage, 5mg, patients lost an average of 35lb.
To put it simply, Mounjaro appears to be the most promising weight loss drug ever invented. It will make billions of dollars. The obesity medicine world is currently waiting for the moment that tirzepatide wins FDA approval as an obesity treatment — after which its manufacturer, Eli Lilly, will likely release a second version of the drug with a new brand name. But many people without type 2 diabetes (and their doctors) have no intention of waiting, and are eagerly using Mounjaro “off-label.”
Mounjaro’s Glucose-Management Benefits Are Unprecedented
With so much hype for tirzepatide (Mounjaro) as a weight loss medication, it’s easy to forget that the medication was originally designed to treat hyperglycemia in type 2 diabetes, a job it does extremely well.
In the SURPASS-1 Trial, which tested the new pharmaceutical for 40 weeks in nearly 500 patients with type 2 diabetes, participants experienced the following results:
A1C. Patients who began the trial with an average A1C of 7.9 percent enjoyed A1C reductions of 1.9 to 2.1 percent. At the end of the trial, a strong majority of patients (81-86 percent) saw their A1C fall to below 6.5 percent, outside of the diabetic range. About half of those who used the highest dosage saw their A1C fall to less than 5.7 percent, completely out of the pre-diabetes range.
Fasting Blood Sugar.The average fasting blood sugar of patients declined by 44-49 mg/dL!
Weight loss. Participants lost an average of 15 pounds (at the 5mg dosage) to 21 pounds (at the 15mg dosage).
Cholesterol. Triglycerides and LDL cholesterol both went significantly down; HDL (“good cholesterol”) went significantly up.
Other trials had similar results in slightly different populations: astounding blood sugar improvements and weight loss, and other health benefits to boot. These numbers easily surpass the results observed in other diabetes medications already on the market, such as metformin or sulfonylureas.
Mounjaro even outperformed daily injections of insulin, widely considered the most powerful glucose-lowering treatment, in two trials. Not only did Mounjaro users enjoy superior blood sugar improvements to insulin users, they also had a significantly reduced risk of hypoglycemia. (Mounjaro also works well when used with insulin.)
How Does Mounjaro Work?
Mounjaro is related to the class of drugs known as GLP-1 receptor agonists, which includes semaglutide (Ozempic, Wegovy, Rybelsus), liraglutide (Victoza), and dulaglutide (Trulicity).
GLP-1 receptor agonists work for patients with type 2 diabetes by mimicking the effects of the hormone GLP-1, which is released by the intestine during meals. GLP-1 does a variety of things: It tells the liver to release less glucose, it slows digestion, and it provokes the feeling of fullness or satiety. Put it all together, and when patients with diabetes take the drug it reduces blood glucose levels while also helping them eat less.
But Mounjaro is not just a GLP-1 receptor agonist; strictly speaking, it is a dual GIP/GLP-1 receptor agonist. The medication additionally mimics another hormone, glucose-dependent insulinotropic polypeptide (GIP), which primarily stimulates insulin production. Combining the activity of both hormones appears to be especially effective, unlocking a synergistic effect.
Cost and Availability
Mounjaro, unsurprisingly, is quite pricey. As of this writing, the sticker price is about $1,000 per month in the United States. The cost is likely to remain high for the foreseeable future.
Insurance coverage for Mounjaro might be somewhat spotty even for people with type 2 diabetes: The drug is so new that experts do not yet know if it has the same positive effects on cardiovascular and kidney outcomes as Ozempic and other GLP-1 receptor agonists. Those critical long-term benefits have helped vault newer diabetes drugs to the forefront of treatment.
It will be even longer before insurance companies cover tirzepatide as a treatment for obesity. Even if the FDA promptly approves the drug as an obesity medicine, insurers may drag their feet before agreeing to pay the very hefty fees. Obesity drugs do not have a great track record, and payers may be skeptical. The unfortunate consequence is that Mounjaro, like Ozempic before it, is becoming a drug of the wealthy.
Side Effects
Ozempic has developed a reputation for nasty side effects. There’s little reason to think that Mounjaro is much different — if anything, the more powerful drug may have even stronger side effects.
Pivotal trials of tirzepatide have shown that up to 33 percent of participants experienced some nausea, and on the higher doses 6–7 percent had to stop taking the drug due to such issues. For some patients, the discomfort may be a price worth paying, but others will be forced to discontinue the drug, or at least dial their dosage back to a lower level.
Mounjaro is also likely to create many cases of so-called “Ozempic face,” a phenomenon in which people lose so much weight that they also lose healthy-looking fat from their faces, resulting in a saggy, aged appearance. Ozempic face is purely caused by weight loss, and is a purely cosmetic issue, though some users may appreciate a warning that not all weight loss improves appearance.
Mounjaro also has a few rare contraindications: It been found to cause tumors in the thyroids of rats, and regulators are recommending that people with a family history of thyroid cancer or multiple endocrine neoplasia syndrome type 2 do not use it. It may be inappropriate for patients with pancreatitis.
A Few Details
Though it may sound like a miracle drug, tirzepatide (Mounjaro) is not intended to replace the most important therapies for obesity and type 2 diabetes: diet and exercise. Mounjaro, like Ozempic, probably needs to be taken forever in order to preserve its benefits. Many members of the diabetes community are wary of taking such a powerful drug for an entire lifetime.
Mounjaro is not a pill; it is self-administered by injection once a week. It will come in the form of an auto-injector pen, similar to an insulin pen, that does not require patients to draw up the medicine themselves. Lilly markets six different dosages, from 2.5mg up to 15mg. New patients are recommended to begin with a starter dose of 2.5mg and gradually work up to larger amounts over a period of months. As patients increase their dosage, they often experience new bouts of gastrointestinal side effects.
Mounjaro is not intended for patients with type 1 diabetes, but there is some hope that it could help the condition. GLP-1 receptor agonists appear to be effective for patients with T1D (when used in addition to insulin), and some doctors prescribe them off-label. It will be years before Lilly receives full approval for that use, if indeed it ever happens.
Mounjaro has not yet been thoroughly evaluated in teenagers or children.
Takeaway
Semaglutide (Ozempic) has taken the world of obesity medicine by storm. Tirzepatide (Mounjaro) causes even greater weight loss, and may soon become the buzzy diabetes drug that people can’t get enough of. Mounjaro has flown somewhat under the radar until now, but demand from people without diabetes has already helped cause shortages of the drug, and now some people with type 2 diabetes are having a difficult time finding the drug that they’ve been prescribed.
Mounjaro may well be the most powerful diabetes drug ever invented. It’s another blockbuster in the making.