New Weight Loss Drugs Are on the Way That Could Upstage Wegovy and Ozempic

Fact checked by Nick Blackmer

Key Takeaways

• Wegovy, Ozempic, and Mounjaro have proven very effective at helping patients control type 2 diabetes and lose weight.

• Early data shows that formulations of drugs in the same class, or higher dose versions of already approved medications, could be even more powerful.

• Some of these experimental drugs can be given as a pill and may be cheaper and easier to make than the injectables.

A new class of drugs has revolutionized the way health providers treat diabetes and obesity. Ozempic, Wegovy, and Mounjaro have seen spectacular success. Patients using the injectable drugs report shedding tens of pounds and getting their blood sugar in check in ways unmatched by prior medications.

But there’s still room for improvement. Drugmakers are testing new ways to give these drugs, and developing new ones that could be even more potent.

Eli Lilly is awaiting go-ahead from the Food and Drug Administration (FDA) to market tirzepatide—sold under the brand name Mounjaro for diabetes treatment—as a weight loss medication. And last month, Novo Nordisk reported that an oral version of semaglutide is as effective at promoting weight loss as Wegovy, the injectable form of the same drug.

Meanwhile, pharmaceutical companies are developing and testing a new crop of experimental weight-loss drugs.

“It’s a really exciting time for people living with metabolic disease and for scientists and healthcare providers. Where the story will ultimately end and what the landscape will look like, I don’t think any of us can predict. The only thing we can say is that the drugs are going to get better and better,” said Daniel Drucker, MD, FRCPC, an endocrinologist and clinician-scientist at the Lunenfeld-Tanenbaum Research Institute at Mount Sinai Hospital in Toronto.

Related: What's the Difference Between Ozempic, Wegovy, and Mounjaro?

Oral Options Are on the Way

Wegovy, Ozempic, and Mounjaro all work by mimicking a hormone called glucagon-like peptide 1 (GLP-1). When a person eats, these GLP-1 based drugs signal to the body to create more insulin. That lowers blood sugar and delays digestion and appetite, making people feel full longer.

New GLP-1 drugs shown to promote weight loss are now only available in injectable forms, but that could soon change.

In May, Novo Nordisk announced that giving a high dose of oral semaglutide, which is currently sold as Rybelsus in lower doses for the treatment of diabetes, works as well as injectable Wegovy at helping people lose weight.

Related: An Oral Version of Wegovy Appears as Effective as the Injectable Version

The same day, Pfizer shared data mid-stage clinical trial showing that a new drug, called danuglipron, led to weight loss and blood sugar control over 16 weeks—on par with other GLP-1 agonists. Unlike oral semaglutide, which must be taken an hour before eating food or taking other medications, Pfizer’s twice-daily tablet can be taken alongside food.

Pfizer is also testing a once-daily oral medication called lotiglipron in phase 2 trials. The company will see how lotiglipron and danuglipron stack up before deciding which to continue testing in phase 3 trials.

Lotiglipron and danuglipron are considered “small molecule drugs,” while semaglutide and tirzepatide are called “peptide-based” drugs. They work similarly in the body, but small molecule drugs can be more effective oral agents and may be more easily combined with other medications.

Eli Lilly is also pursing an oral GLP-1 agonist called orforglipron.

The development of small molecule GLP-1-based drugs represents “a big advance in the field,” Drucker, who specializes in glucagon-like peptides, told Verywell.

“For people with diabetes and obesity, this is all very good news. It means in a couple of years, maybe two to three years, you will have one or more options to take GLP-1 as a small molecule tablet,” Drucker said. “The more options the better for people living with diabetes.”

There’s not enough clinical trial data on these experimental drugs to know how they compare with oral semaglutide. But it’s likely that they will, at least, be cheaper. That’s because biological proteins are more expensive to create and challenging to scale up production. Pfizer’s small molecule, on the other hand, will likely be easier to mass produce, and less likely to experience shortages seen with Wegovy and Ozempic this year.

Another Injectable Has Potential to Be Stronger than Mounjaro

Tirzepatide, currently sold as Mounjaro for treating diabetes, is the most effective medication at promoting weight loss, according to late-stage clinical data presented by drugmaker Eli Lilly. In May, the company asked the FDA to approve a weight loss indication for the drug.

Related: Mounjaro Generic May Soon Join Wegovy as a Weight Loss-Approved Drug

As with the other drugs in this class, tirzepatide works by mimicking GLP-1. But it also acts on a different hormone, called gastric inhibitory polypeptide (GIP).

Now, Lilly is testing a drug that affects GLP-1 and GIP, and yet another hormone, called glucagon. This so-called tri-agonist, which is now in mid-stage human trials, could be even more efficacious than tirzepatide, according to David Lau, MD, PhD, director of the Julia McFarlane Diabetes Research Centre at the University of Calgary.

In a mouse study, retatrutide promoted more body weight loss than tirzepatide in obese mice. The animals treated with the drug also appeared to burn more energy than the mice on placebo, despite being on the same calorie restriction.

Even More Obesity Management Stars on the Horizon

None of the currently-available GLP-1 agonists quite rival bariatric surgery—the current gold standard for obesity treatment—but they may be close. Drucker said that staying on medications for the rest of one’s life may be more burdensome than a one-and-done surgery. Yet Lau emphasized that up to a quarter of patients who undergo bariatric surgery see weight regain, while people who adhere to weight loss medications may not.

Studies are underway to better understand how the drugs in this class stack up. For instance, Lilly is studying tirzepatide head-to-head against semaglutide for obesity. Novo Nordisk, meanwhile, is testing semaglutide in dosages up to three times the currently approved highest dose.

The outstanding question, then, is whether a higher dose of semaglutide can compete against the efficacy of tirzepatide. And once newer drugs are on the market, how will the newest generation of medications fit together?

“We just don’t know that yet,” Drucker said. “There are so many different types of combinations that are being tested, and many of them will be better than what we have so far with semaglutide or tirzepatide.”

Even if increasing dosages of the current or upcoming GLP-1-based drugs made them more effective, the side effects of those high dosages may make them untenable for most people.

“The major limiting factor of any of these single, dual, or triple agonists is nausea, vomiting, diarrhea, and constipation. If we can overcome those side effects, there are no limits,” Lau told Verywell.

Some experimental obesity and diabetes treatments are breaking out of the GLP-1 class. For instance, researchers are testing a once-monthly intravenous treatment that not reduces body weight, but also increases lean muscle mass.

These advancements are coinciding with a new era in medicine—one that recognizes obesity as a chronic relapsing condition, Lau said.

“Drugs like Ozempic and Wegovy have really changed the whole landscape in the sense that we now recognize that obesity is more than just a lack of willpower,” Lau said. “The control of appetite is much more complex than just having the will to stop or cut back on eating. The ‘eat less, move more’ narrative doesn’t quite work anymore.”

What This Means For You

While the future is bright for weight loss medications, right now, only Wegovy can be prescribed on-label for weight loss. A healthcare provider can help you understand whether GLP-1 agonists or other treatments are right for you.