With another popular weight-loss drug about to hit the market this year, the director of the University of South Carolina Medical Center Weight Management sat down with MUSC Catalyst News to talk about:
- An impressive percentage of pounds have been dropped by people using the new weight loss drug tirzepatide in clinical trials.
- Other drugs are already on the market, such as Wegovy and Saxenda, that have found success.
- How its popularity causes shortages in drug supplies for people with type 2 diabetes.
- Who qualifies for a prescription for weight-loss medication.
- Side effects and costs.
That’s a lot of ground to cover, but Patrick O’Neill, PhD, is more than up to the task. In addition to his leadership of the Center for Weight Management at the MUSC Health and Wellness Institute at Mount Pleasant, he is a professor in the MUSC School of Medicine and past president of the Obesity Association. O’Neill also studies and leads clinical trials of medications and treatments designed to help people manage their weight — including one drug discussed in this article.
The new weight loss drug, terzipatide
There is a lot of hype around a weight loss drug that is expected to hit the market this year. Its manufacturer, Eli Lilly, has not yet announced a brand name, but the drug it contains is called tirzepatide.
Tirzepatide is already in a diabetes drug called Mounjaro. The weight loss drug may contain more tirzepatide than Mounjaro contains, to boost its power at helping people drop pounds.
This power is awesome. O’Neill said tirzepatide worked so well in clinical trials for weight loss that it received fast-track designation from the Food and Drug Administration. This speeds up the process of getting important new medicines to people who need them.
“In the Phase III trial, they achieved weight losses of up to 20% of the person’s baseline body weight,” O’Neill said. That was 50 to 60 lbs in some cases.
Tirzepatide works by helping the patient feel full when eating less food and by slowing the passage of food through the digestive tract. There is no doubt that the weight loss it leads to is beneficial for people who are overweight or obese. But there are a few other factors to consider, which O’Neill will address later in this article.
Other weight loss drugs are already on the market
Tirzepatide comes on the heels of two injectable weight loss medications that have made a splash in recent years. Like tirzepatide, it developed from diabetes medications, which reduce appetite and slow the emptying of food from the stomach..
The first was liraglutide, brand name Saxenda, for obesity, and it was originally marketed only to treat diabetes under the brand name Victoza.
“What they found in clinical trials is that people with diabetes who take liraglutide also tend to lose weight. So they started studying it at a different dose, a higher dose for weight loss specifically, with or without diabetes. And they found that it had a significant effect on weight loss. “The average loss was about 6 or 7% or more over the course of a year,” O’Neill said.
The next big weight loss drug to emerge was semaglutide, under the brand name Wegovy. As a treatment for diabetes, it is called Ozempic. Again, the weight loss version contains more semaglutide than the diabetes treatment.
“They basically mimic a naturally produced peptide that is made in the gut. It tends to help regulate glucose and contribute to a feeling of fullness. This is also true of liraglutide and terziepatide.
He played a role in ensuring Wegovy worked as it was intended to. MUSC has participated in several semaglutide trials. You see an average weight loss of about 15% to 16% of a person’s starting weight. This is a much higher percentage than has ever been observed with any weight loss medications previously approved by the FDA. “
Some scientists have described semaglutide as a game-changer, O’Neill said. “It’s a big deal. But it’s not a cure-all. I want to stress that you need to use FDA-approved obesity medications along with diet and exercise. So they’re not meant to be a simple solution to a complex problem. But This is a much larger effect than we’ve seen from any previously approved obesity drug.”
Effects on diabetes drug supply
This game-changing reputation has come at a cost—both to people with diabetes and people who want to lose weight. The high demand for Wegovy and unofficial prescriptions for Ozempic for weight loss have resulted in a shortage leading some patients to look for alternatives.
Monjaro is also on the Food and Drug Administration’s drug shortage list. So is another diabetes drug called Trulicity, which is not a weight-loss drug but is also prescribed off-label, because in some cases, diabetics who used it lost weight.
Who qualifies for a prescription for weight-loss medication?
When it comes to previously prescribed weight loss medications that are already on the market, there are qualifiers. Saxenda is for adults with a BMI of 27 or higher and for children ages 12 to 17 who are obese. Everyone who takes it is required to cut calories and increase exercise.
Wegovy is also used for adults with a BMI of 27 or higher. They are supposed to eat less and move more, too. The U.S. Food and Drug Administration recently approved Wegovy for children ages 12 and older with a high BMI.
Side effects and costs
Almost every drug has side effects, O’Neill said, and weight-loss medications are no exception. “These medications that I’ve been talking about are all gut medications, basically. They mimic the hormones that are produced in the digestive system. So their side effects tend to be primarily digestive side effects. Many complain of nausea, and less frequently, vomiting, diarrhea, or constipation.”
He said patients should start with a low dose, and gradually increase the dose to the target level.
“What we’ve found in studies is that we see side effects, like diarrhea, nausea, etc., that they tend to be transient in general. So over time, people tend to get over them. We’ve had very few people who have had to come off medication.” in studies because of side effects.”
He said gallstones and gallbladder problems are also potential problems. But the discomfort may not only be physical. O’Neill said the drugs are expensive—more than $1,000 a month. Most insurance plans do not cover medications or any type of obesity treatment. So it’s a medical condition that is really discriminated against in many different ways.”
It is also a condition that is being carefully studied due to the increasing number of people who are overweight or obese. “I always maintain that there is no medicine, no obesity medicine that works for everyone. No obesity medicine will work on its own without you doing your part. And they only work when you take them. But people need to treat these as serious treatments for a serious condition.”