Weight-loss drugs Ozempic, Wegovy: What you should know
WeightWatchers, a 60-year-old weight-loss company, announced this month that it would buy a telemedicine company whose suppliers prescribe anti-obesity drugs to a growing number of eager online subscribers.
The $132 million deal with Sequence is just the latest commercial boost in the red-hot prescription drug market that promises dramatic weight loss. Diabetes drug Ozempic has been touted by celebrities on social media for months, even though it's not approved for weight loss. The demand for it sparked a shortage.
WeightWatchers will introduce its roughly 3.5 million subscribers to a new generation of medicines that go beyond behavior change like gym workouts and diet tracking. Obesity experts say the drugs could revolutionize treatment for a disease that affects 42 percent of U.S. adults.
The following are the efficacy and precautions for these new drugs.
What Are These New Weight Loss Pills?
The drugs that have attracted the most attention come from a class of drugs called GLP-1 agonists. Two of the most popular are Ozempic and Wegovy, which are different doses of the same drug, semaglutide.
Ozempic has been used for six years to treat type 2 diabetes but is not approved for weight loss. Wegovy was approved in 2021 to treat obesity in adults and was approved late last year to treat children and adolescents 12 and older.
Doctors prescribe the drug to people who have diabetes alone, or to people who are obese or overweight and have other health problems. Most of these types of drugs are delivered by weekly injections.
Supply problems and soaring demand led to shortages of the drugs last year, but manufacturer Novo Nordisk said they had been replenished.
How do the medicines work?
They mimic the action of gut hormones after a person eats, promoting the release of insulin, preventing the liver from producing sugar and suppressing appetite.
A newer drug called tirzepatide mimics the action of both hormones and works even better. An Eli Lilly and Co. drug sold under the Mounjaro brand name is already approved to treat diabetes, but the FDA granted fast-track status to review it for treating obesity. A decision is expected this spring.
People using these drugs eat less and lose weight due to decreased appetite and increased feelings of fullness.
How effective are the medicines?
In one clinical trial, adults taking Wegovy lost an average of nearly 35 pounds, or about 15 percent of their starting body weight. Teenagers lost about 16 percent of their body weight.
An ongoing clinical trial of Mounjaro found average weight loss of 15% to 21%, depending on dose, compared with about 3% in people taking a placebo or dummy drug.
Why not just diet and exercise?
In a typical weight-loss program in which participants rely solely on diet and exercise, about a third of participants lose 5 percent or more of their body weight, notes Dr. Louis Aronne, director of the Center for Integrative Weight Control at Weill Cornell Medicine.
Most people find it difficult to lose weight due to the body's biological response to eating less, he said. Several hormones respond to reduced calorie intake to increase hunger and maintain body weight.
“It's a real physical phenomenon,” he said. “There's a resistance mechanism that's a coordinated effort by the body to keep you from losing weight.”
What are the side effects?
The most common side effects are transient gastrointestinal problems such as nausea, vomiting, diarrhea, stomach pain, and constipation.
Other possible side effects include thyroid tumors, cancer, inflammation of the pancreas, kidney and gallbladder, and eye problems. People with a family history of certain thyroid cancers or rare inherited endocrine disorders should avoid these drugs.
what to pay attention to
The new drugs could be an effective part of a multifaceted weight loss approach, said Dr. Amy Rothberg, an endocrinologist at the University of Michigan who directs a virtual weight management and diabetes program called Rewind.
But she worries that programs like WeightWatchers are primarily interested in boosting enrollment and profits.
“I want them to do their due diligence and have real monitoring of the patients who are taking the drugs,” she said.
It's important to make sure patients are taking their medicines for their intended purpose, making sure there's no reason not to take them, and monitoring them for side effects, she said.