A brand new drug has been approved for patients with type 2 diabetes, and it’s now available. It may prove to be the most effective type 2 diabetes drug ever developed.

The drug is tirzepatide (Mounjaro), and it is the innovation of the pharmaceutical giant Eli Lilly and Company.

In Trials, Mounjaro’s Benefits Are Unprecedented

Mounjaro is a highly effective glucose-lowering injection that also leads to impressive and apparently effortless weight loss.

As earlier reported by our friends at diaTribe, tirzepatide (Mounjaro) has been tested in multiple large clinical trials, all of which showed that the medication leads to extraordinary blood sugar improvements for patients with type 2 diabetes.

I’ll review just one such trial in detail: the SURPASS-1 Trial, which tested the new pharmaceutical for 40 weeks in nearly 500 patients with type 2 diabetes.

• A1C. The patients, who began the trial with an average A1C of 7.9%, enjoyed A1C reductions of 1.9 to 2.1%. At the end of the trial, a strong majority of patients (81-86%) saw their A1C fall to below 6.5%, outside of the diabetic range. About 50% who used the highest dosage saw their A1C fall to less than 5.7%, 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.

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 than insulin users, they also had a significantly reduced risk of hypoglycemia. (Mounjaro also works well when used with insulin.)

Mounjaro and Weight Loss

And then there’s the matter of the miraculous weight loss. Every one of the trials mentioned above showed that Mounjaro patients lost a massive amount of body weight.

If anything, doctors (and investors) are even more excited about tirzepatide’s potential as a weight-loss drug than as a diabetes drug. We covered this extensively in a recent story: These Two Diabetes Drugs Could Completely Change Weight Loss and Obesity Treatment.

At its highest dosage, tirzepatide helped overweight patients lose 22.5% of their body weight in 72 weeks, a completely jaw-dropping result on par with the massive benefits from bariatric surgery. Even at its lowest dosage, 5mg, patients lost an average of 35lb.

To put it simply, this appears to be the most promising weight loss drug ever invented. Although it has not yet been approved as a weight-loss drug, patients that use it for diabetes will be the first to enjoy these benefits.

Assuming it is eventually approved as a weight-loss medication, tirzepatide may be marketed separately for weight loss under a different name than “Mounjaro.”

How Does Mounjaro Work?

Mounjaro is related to the class of drugs known as GLP-1 receptor agonists. These medicines work for patients with type 2 diabetes by mimicking the effects of the hormone glucagon-like peptide 1 (GLP-1), which is usually 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.

There are several GLP-1 receptor agonists already available for patients with diabetes. In the United States, they’re sold under the following brand names:

• exenatide (Byetta, Bydureon)
• liraglutide (Victoza)
• lixisenatide (Adylixin)
• dulaglitide (Trulicity)
• semaglutide (Ozempic, Rybelsus)

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.

Mounjaro has all of those positive effects, but it additionally mimics another hormone, glucose-dependent insulinotropic polypeptide (GIP). The combination appears to be even more effective.

Cost and Availability

Mounjaro, unsurprisingly, is quite pricey. As of this update, filed in November 2022, the sticker price is about $1,000 per month. The cost is likely to remain high for the foreseeable future, although we can hope that insurers become increasingly eager to cover that cost, given the impressive benefits.

There’s no word yet on availability in other countries. Competitor Wegovy has been so popular in the United States that its maker has temporarily hit the brakes on advertising its new miracle drug.

A Few Details

Mounjaro is not intended to replace the most important therapies for type 2 diabetes: diet and exercise.

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 will market 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.

Some side effects (particularly gastrointestinal distress) and contraindications have been announced. Because Mounjaro has been found to cause tumors in the thyroids of rats, 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.

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 may 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.