Mounjaro can be prescribed online
Order OnlineWhat is Mounjaro?
"Mounjaro" is the latest "long-acting GIP/GLP-1 receptor agonist" that acts not only on GLP-1, which is well-known in medical weight loss, but also on GIP hormone receptors. Clinical trial results have shown that GIP/GLP-1 receptor agonists, with the assistance of GIP, have a stronger appetite suppressive effect and weight loss effect than GLP-1 receptor agonists. The impactful figure above shows the results of weight loss effects from a clinical trial (SURMOUNT-1) using placebo and Mounjaro. For more details, please refer to the clinical trial section below.
Mechanism of Action of Mounjaro (Tirzepatide・GIP/GLP-1 Receptor Agonist)
GIP and GLP-1 are names of hormones called incretins, secreted from different cells in the small intestine. GIP and GLP-1 are secreted after meals and promote insulin secretion from the pancreas in a glucose-dependent manner, and have the effect of suppressing appetite and making one feel less hungry by slowing down gastrointestinal motility. This effect naturally reduces food intake and leads to weight loss.
In addition, incretin hormones are said to act on various organs and have effects such as improving fatty liver and reducing cardiovascular risk.
Furthermore, the newly added GIP has many beneficial effects on adipose tissue.
- GIP increases blood flow to abdominal adipose tissue.
- GIP effectively breaks down and metabolizes lipids (triglycerides) in adipose tissue, thereby reducing fat accumulation.
- In obese individuals, the increase in blood flow to adipose tissue due to meals and GIP is blunted, but it has been reported to partially recover with weight loss.
- GIP directly promotes lipogenesis in adipocytes.
- GIP promotes the activation of lipoprotein lipase, an enzyme involved in lipid breakdown and the uptake of circulating free fatty acids, in human adipocytes cultured ex vivo.
- GIP promotes insulin sensitivity, glucose uptake, de novo lipogenesis, and lipolysis in isolated rat adipocytes.
- In mice and non-human primates, impaired GIP function has been reported to reduce adipose tissue accumulation and lower the risk of diet-induced obesity.
It is said that Mounjaro is effective for weight loss due to the synergistic effects of not only GLP-1 but also GIP.
What makes Mounjaro so superior to previous GLP-1 receptor agonists (Ozempic)?
Previous GLP-1 receptor agonists (Ozempic, Saxenda, Rybelsus, etc.) were medications that acted only on 'GLP-1,' as their name suggests. However, Mounjaro, which has just been released, is a 'GIP/GLP-1 receptor agonist,' meaning it acts on 'both GIP and GLP-1.'
The figure below compares GIP receptor agonists, GLP-1 receptor agonists (such as Saxenda, Rybelsus, and Ozempic), and GIP/GLP-1 receptor agonists. Previous research showed that GIP alone did not significantly reduce weight, but it was concluded that with the assistance of GIP, GIP/GLP-1 receptor agonists were superior to GLP-1 receptor agonists in terms of weight loss, food intake, and fat mass.
(From top: GIP receptor agonist, GLP-1 receptor agonist, GIP/GLP-1 receptor agonist)
Mounjaro Weight Loss Effects: Clinical Trial Introduction
SURMOUNT-1 Trial (Mounjaro vs. Placebo)
The SURMOUNT-1 clinical trial compared 'Mounjaro (tirzepatide) and placebo'. This clinical trial showed results from 72 weeks of administration to 2539 people with BMI 30 or 27 or higher, and other non-diabetic complications. The figure above clearly shows the remarkable effect of Mounjaro compared to placebo. (Grey: placebo, lighter blue to darker blue: Mounjaro 5mg/10mg/15mg) Even at the non-maximal dose of Mounjaro 5mg, a significant weight loss effect was observed (average weight loss: -16kg).
SURMOUNT-2 Trial (Mounjaro vs. Ozempic)
The SURMOUNT-2 clinical trial compared 'Mounjaro (tirzepatide) and Ozempic (semaglutide/GLP-1 receptor agonist)'. This clinical trial showed results after 40 weeks of administration to 1,878 patients with type 2 diabetes (on metformin) and an average BMI of 34.2. The figure above clearly shows the remarkable effect of Mounjaro compared to Ozempic 1mg. (Grey: Ozempic 1mg, lighter blue to darker blue: Mounjaro 5mg/10mg/15mg). It is surprising that Mounjaro 5mg showed a greater weight loss effect than the maximum dose of Ozempic 1.0mg.
How to Use Mounjaro
This medication is administered once a week. Start with 2.5mg/dose and increase to 5mg/dose after 4 weeks (from the 5th dose). The usual maintenance dose of Mounjaro is 5mg. The dose can be adjusted as needed, and if 5mg is insufficient, the dose can be increased by 2.5mg at intervals of 4 weeks or more. However, the maximum dose is 15mg.
How to Administer Mounjaro
There are only 3 steps to use!
- Remove the cap
- Place the base on the skin and unlock
- Press the injection button and wait for 10 seconds
For detailed instructions, please refer to the insert included with the medication or the figure below.
If you forget to administer Mounjaro
This varies depending on whether it's less than or more than 72 hours from the scheduled administration date, as shown below.
If you are concerned, please contact the clinic!
Is it really okay to administer Mounjaro once every 7 days?
As shown in this figure, the blood tirzepatide concentration of Mounjaro changes in this way, and the half-life of the drug is approximately 5-6 days, allowing it to act for a long period. Weekly administration is possible, reducing the burden of injections on patients. Since it is a long-acting drug, please be sure to adhere to the weekly administration period, and do not administer it daily or every other day, as this is dangerous.
Who cannot use Mounjaro / Who is it not recommended for?
The following individuals cannot be prescribed this medication at our clinic.
・Those with a history of allergic reactions to this medication.
・Those with a BMI of 23 or less (due to precautions in the official package insert).
・Those with severe gastrointestinal disorders (e.g., severe gastroparesis) (gastrointestinal symptoms may worsen even without prior experience).
・Those with a history of pancreatitis or thyroid disease.
・Patients or conditions at risk of hypoglycemia.
- Those engaging in intense physical exercise.
- Those with excessive alcohol consumption.
・Pregnant women.
・Breastfeeding mothers.
・Elderly individuals.
・Those taking birth control pills or warfarin (a blood-thinning medication) (not contraindicated, but may reduce the effectiveness of the medication).
Common side effects of Mounjaro
The side effects of Mounjaro are generally the same as those of GLP-1 receptor agonists, and the frequency is said to be similar (gastrointestinal symptoms are reported slightly more often than with GLP-1 receptor agonists).
In clinical trials, gastrointestinal symptoms such as nausea, vomiting, diarrhea, and constipation were reported as side effects in over 5% of patients.
As shown in the figure below, adverse gastrointestinal reactions can be alleviated by reducing meal portions, avoiding fried foods, and stopping eating once feeling full.
Also, pay attention to the following serious side effects:
- Hypoglycemia (caution is needed when used with other medications): If symptoms like those shown in the figure below appear, consume sugar.
- Acute pancreatitis (less than 0.1%) *Although rare, if you experience sudden abdominal pain, stop administration and seek medical attention immediately.
When will Mounjaro (tirzepatide) be released in Japan?
Mounjaro was approved in the United States in May 2022 and began sales in June. It recently received approval from the European Medicines Agency. In Japan, Mounjaro 2.5mg and 5mg are the latest GIP/GLP-1 receptor agonists, with sales starting in April 2023.
Mounjaro (Tirzepatide) insurance coverage
As of April 2023, Mounjaro is only approved in Japan as a 'Type 2 Diabetes Mellitus Treatment', and prescriptions for weight loss purposes are out-of-pocket. However, it has shown clear weight loss effects in clinical trials, so there is significant interest and expectation for its use as an obesity treatment.
Where can I buy Mounjaro (Tirzepatide)? Is it safe?
If you would like to know more about Mounjaro (tirzepatide) or other medicines from a doctor or specialist, please consult Mona Aoyama Clinic's free online consultation!
References
https://www.nature.com/articles/s41574-022-00783-3
Eli Lilly | Mounjaro® (Tirzepatide)
N Engl J Med. 2021;385(6):503-15.
Lancet. 2021;398(10295):143-55.
https://www.sciencedirect.com/science/article/pii/S0168822723005338
