Eli Lilly gets FDA approval to sell Mounjaro as obesity drug called ...

Eli Lilly’s blockbuster drug tirzepatide, sold as Mounjaro for type 2 diabetes, has been cleared to treat obesity, making it the second in a highly effective class of weight loss medications to enter the market.

The Food and Drug Administration’s long-awaited approval of the injectable drug, which will be marketed under the name Zepbound for obesity, is a milestone for Lilly. It also introduces stiff competition for Novo Nordisk, which has had to limit starter doses of its obesity treatment Wegovy due to ongoing shortages.

“In light of increasing rates of both obesity and overweight in the United States, today’s approval addresses an unmet medical need,” John Sharretts, director of the Division of Diabetes, Lipid Disorders, and Obesity in the FDA’s Center for Drug Evaluation and Research, said in a statement.

Novo’s Wegovy (like its sister diabetes drug Ozempic) targets receptors of the GLP-1 hormone, and has shown in trials to cut around 15% of people’s body weight. Meanwhile, Zepbound, which targets both the GLP-1 and GIP hormones, has shown up to 21% weight loss in trials.

The most common side effects for both medicines include nausea, diarrhea, and vomiting. Both treatments have a boxed warning for the potential risk of thyroid C-cell tumors.

The debut of this class of GLP-1-based medicines has led to explosive demand in the U.S., where roughly 70% of people meet the FDA’s definition of having overweight or obesity. Both Novo Nordisk and Lilly have intermittently struggled to manufacture enough product to meet demand, leading some patients to turn to compounding pharmacies and loosely regulated suppliers for knock-off versions of the medicines.

Insurers have also limited access to these new medications, which are costly and meant to be taken indefinitely.

Lilly will sell Zepbound at a list price of $1,059.87 per month, about the same price as Mounjaro and about 20% lower than the price of Novo’s Wegovy. Lilly is also introducing a savings card program for people with commercial insurance.

Lilly expects the drug to be available in American pharmacies after Thanksgiving. In an effort to prevent future shortages, the company plans to have roughly doubled its manufacturing capacity by the end of the year, CEO David Ricks said on a conference call with reporters. Only about 5 million people in the U.S. receive any form of GLP-1 treatment, Ricks said, but there are roughly 50 million Americans who would be eligible for Zepbound and who have commercial insurance that covers obesity treatments.

“We know with such an effective medication there’ll be a lot of demand,” Ricks said. “We’re stepping up to that challenge and hope to fulfill it in the coming years.”

Separately Wednesday, regulators in the U.K., where Mounjaro is also approved for diabetes, expanded the drug’s authorization to include obesity. Once receiving approval, treatments in the U.K. do not become available as quickly as they do in the U.S. as reimbursement deals are negotiated, but Ricks said “we see it launching in the U.K. sooner than later.”

Before Zepbound’s U.S. approval, many doctors had already been prescribing the diabetes version, Mounjaro, to patients with obesity off-label, but in recent months, insurers have been clamping down on off-label usage, sending threatening letters to doctors and requiring pharmacies to check for diabetes diagnoses.

Now, “having this obesity indication for those patients that have obesity medication coverage – it opens up the door for another treatment option,” said Cate Varney, the obesity medicine director at the University of Virginia Health System.

The drug, as a treatment for diabetes, had already rapidly become Lilly’s top-selling product. The company made about $3 billion in revenue from the medication in the first three quarters of this year, and the treatment’s long-term potential has made Lilly the most valuable pharmaceutical company in the world, with a market capitalization of nearly $600 billion.

Given the current shortages of Wegovy, the potential higher efficacy of Zepbound, and its lower price, doctors would likely opt to prescribe Zepbound instead of Wegovy for many patients with obesity — giving Lilly an edge over Novo in the race to dominate what analysts estimate could become a $100 billion obesity market.

However, Novo has longer-term data backing up the safety and benefits of Wegovy. At a cardiology conference this week, the drugmaker will release full results of a trial that show Wegovy cut the risk of major cardiovascular problems in people with obesity. Lilly is running a similar trial for Zepbound, but that study isn’t expected to end until 2027.

Varney, the UVA doctor, said that since Wegovy has concrete data on its cardiovascular benefits, it would be easier to argue to insurers to cover it compared with Zepbound.

Even though Lilly executives stress that the company is expanding manufacturing capacity, supply will likely be a continuing challenge given the immense demand for effective obesity treatments.

“I have fears that the same thing is going to happen [as] with Wegovy,” said Varney, “where we’ll get into this situation where we’re full go to prescribe these medications, but then within six months we’re getting notification that we need to start to pull back.”

Lilly, Novo, and an expanding group of pharmaceutical companies are at work on next-generation therapies that could prove more potent and more convenient than the current crop of medicines.

Ania Jastreboff, director of the Yale Obesity Research Center, who has helped lead trials for Zepbound, said that having more approved drugs for obesity can allow doctors to better tailor treatments for patients. Research is currently underway trying to better determine which patients respond best to which obesity medications.

“For other chronic, complex diseases, we have many different choices of therapy for different patients,” she said. “We’re at the start of that in terms of obesity treatment and in terms of the availability of highly effective, anti-obesity medications.”

Andrew Joseph contributed reporting.

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