Wegovy, Mounjaro, Ozempic… These drugs are driving the pharmaceutical industry crazy and fueling the hopes of millions of patients suffering from diabetes or obesity around the world. What are they, how do they work and who makes them?
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These drugs mimic a hormone secreted by the intestines, GLP-1.
They can be used for weight loss and/or against type 2 diabetes, the most common, which is characterized by high blood glucose levels (hyperglycemia).
They work in particular by promoting the secretion of insulin — which lowers glucose levels –, by slowing down the emptying of the stomach and by sending a signal of satiety to the brain.
They are currently administered by injection and can have side effects such as nausea and vomiting or gastrointestinal upset.
Expensive, they have become real moneymakers for the pharmaceutical laboratories that market them.
The molecule liraglutide
Studies show that if treatment is stopped, patients regain weight.
The liraglutide molecule was developed by the Danish group Novo Nordisk.
It was approved in 2009 in Europe and 2010 in the United States for diabetes, under the name Victoza.
It was then approved for obesity in 2014, under the brand name Saxenda, becoming the first GLP-1 analogue approved for weight loss.
But both drugs have a drawback: they must be injected daily.
Semaglutide
Novo Nordisk is therefore developing a new molecule, semaglutide, which can be injected once a week.
Ozempic was approved in 2017 for type 2 diabetes in the United States and quickly became a hit, promoted on social media for its weight-loss properties and often taken beyond its primary indication.
Its counterpart against obesity, using the same molecule, was authorized in 2021 in the United States, under the name Wegovy.
In 2024, Wegovy is approved by the American health authorities to specifically prevent cardiovascular accidents in obese or overweight people.
Tirzepatide molecule
The American laboratory Eli Lilly developed the tirzepatide molecule.
It is authorized in 2022 in the United States under the name Mounjaro for people suffering from type 2 diabetes.
In 2024, its counterpart against obesity, also administered weekly, is approved by the American health authorities, under the name Zepbound.
In addition to GLP-1, tirzepatide contains another gastrointestinal hormone (GIP), to enhance its effects.
According to a recent study, it causes greater weight loss than Novo Nordisk’s semaglutide.
