The obesity drug revolution

One study can start a pharmaceutical revolution.

Four years ago, a large clinical trial run by Novo Nordisk showed a drug called semaglutide helped people with obesity lose, on average, around 15% of their weight. The results far exceeded what prior studies of other treatments had suggested was possible pharmaceutically, sparking a rush to research that has quickly reshaped the obesity drug field.

Demand for semaglutide, now sold in a handful countries by Novo as Wegovy, has surged to such heights the company can’t keep up. Physicians see Wegovy and other drugs like it as powerful treatments for obesity as well as its many related health consequences.

Analysts forecast annual sales of this new class of medicines to surpass $100 billion by early next decade. Drugmakers are investing billions of dollars in an attempt to get a piece of that market, as would-be competitors test new ways to regulate metabolism and spur weight loss.

Some 120 drugs are now in clinical development for obesity, according to a recent report from Iqvia, from Wegovy mimics to psilocybin and coated glucose beads. More than one-third work by stimulating gut hormones like GLP-1 — the target of Wegovy.

To succeed, they’ll likely have to at least match the double-digit weight loss numbers shown in testing for Wegovy and Zepbound, a rival drug from Eli Lilly approved in the U.S. last year. Here’s where the field stands:

How well do current drugs work?

Until the early 2010s, physicians had only a few drugs they could prescribe for obesity, one of which, phentermine, was first approved in 1959. A spurt of research in the early 2000s led to the 2012 and 2014 approvals of three more treatments: Qsymia, Belviq and Contrave.

While those drugs showed greater weight loss than placebo in testing, their effects were largely seen as unexceptional, resulting in limited uptake. Qsymia in particular was linked with safety issues, including the risk of fetal toxicity and heart problems. Belviq, meanwhile, was withdrawn in 2020 due to an association with higher rates of cancer.

Their launches came around the time the the first GLP-1 drugs arrived on the market for diabetes. Novo, after seeing the weight loss effects of its diabetes drug Victoza, developed a daily injectable version specifically for obesity. Dubbed Saxenda, it had only a modest impact on weight and never caught on widely, either.

Novo was quick to advance successor GLP-1s, however. While working on the weekly injection that became the diabetes drug Ozempic, Novo simultaneously studied a formulation for weight loss. Importantly, the company also committed to a longer-term plan designed to prove the expected weight loss benefit would help protect the heart.

Both bets paid off. Treatment with Wegovy, which contains the same active drug as Ozempic, reduced weight by an average of 10% to 16% across a range of studies — approaching levels typically achieved via bariatric surgery.

A large study, meanwhile, proved weight loss from Wegovy reduced the relative risk of heart attacks, strokes or cardiovascular death by 20%, compared to a placebo. U.S. approval for this use last year made Wegovy the only weight loss drug that can be marketed as having such benefits. The new label helped push Medicare, which is prohibited by law from reimbursing for obesity treatment, into covering Wegovy for some people.

Yet Lilly may ultimately have an upper hand with its rival drug Zepbound. On a surface-level comparison, Zepbound led to greater average weight loss in testing, showing reductions between 13% and 21%, depending on the study and dose. Additionally, a larger share of participants in Lilly’s studies experienced at least 10% weight loss than did participants in Novo’s testing of Wegovy.

The two medicines have never been compared head to head in a trial, so no definitive conclusion can be drawn about their relative weight loss benefits.

Lilly doesn’t have heart data to match Novo yet. A similarly large Zepbound trial, called SURPASS-CVOT, should produce data in 2025, potentially putting an expanded label for the drug two years behind Wegovy. Lilly is testing Zepbound against an active medicine, its older GLP-1 drug Trulicity, which could strengthen its case.

Zepbound is likely to show a similar heart benefit to Wegovy, according to Angela Fitch, president of the Obesity Medical Association and chief medical officer at the Massachusetts clinic Knownwell.

“There’s been a positive effect on cardiovascular health from the less potent GLP-1s,” she noted.

What could new drugs improve upon?

Novo and Lilly have set the bar high with Wegovy and Zepbound, so much so that some in the industry are describing those drugs’ benefits as “table stakes” for would-be rivals. Competitors will need to show an advantage in efficacy, safety or convenience.

Current GLP-1 drugs for weight loss are delivered via an under-the-skin injection. (Although Novo does sell an oral version of Wegovy for diabetes.) A pill with similar potency could be attractive to people who’d prefer to avoid needles. However, peptide-based drugs like GLP-1s are difficult to deliver through the digestive tract, where they are broken down by enzymes and absorbed only slowly due to their relatively large size.

Another approach could target the drugs’ known side effects. GLP-1s are often associated with gastrointestinal problems such as nausea and vomiting. There are also concerns, based on an animal and biomarker data, of a possible link to certain types of cancer. This could make other proposed mechanisms for stimulating weight loss, such as blocking cannabinoid or opioid receptors, more attractive.

Companies hoping to make inroads on Wegovy and Zepbound might also try to improve on how readily existing GLP-1s are absorbed and used by the body. Both Novo and Lilly have had difficulty manufacturing enough of the drugs, and a formulation that’s more easily taken up by the body could allow for lower doses.

Drug developers are looking, too, at how to preserve lean mass, as the rapid weight loss from current GLP-1s also leads to unwanted reduction in muscle tissue. Patients taking Zepbound lost 11% of their muscle mass in a substudy of a major trial that led to its FDA approval, for example.

Shrinking muscle mass is particularly concerning for older people for whom less strength could increase frailty. And if people regain weight after significant losses, the subsequent gains tend to be disproportionately fat.

Lean mass also plays an important role in metabolism, as muscles burn more energy at rest than fatty tissue and secrete a hormone that spurs glucose uptake.

“We tend to think of a muscle as a motor — it moves things from one place to another,” said Peter Ackerman, vice president for clinical development at Biohaven, which is developing a muscle-building drug in both obesity and the rare disease spinal muscular atrophy. “I think it has many more important roles to play in our overall health.”

What’s next?

Lilly and Novo aim to maintain their current hold on the market. Both companies are testing several experimental drugs with the goal of launching oral versions or even more effective treatments than their current products.

Novo is already close to completing a Phase 3 trial program testing an oral form of Wegovy. It also has in late-stage development a combination of Wegovy with a compound called cagrilintide that acts on a gut hormone called amylin.

Lilly has two drugs in Phase 3: an oral GLP-1 dubbed orforglipron that is approaching key data readouts next year and an injectable treatment called retatrutide that stimulates GLP-1, GIP and a third hormone known as glucagon. Results in obesity are due in 2026.

Lilly has four experimental drugs in Phase 1 or 2, while Novo has five.

“[Lilly and Novo] cover all the bases,” said Clive Meanwell, CEO of Metsera, a newly launched startup that has two obesity drugs in clinical testing. “Our belief is it's going to be a portfolio play, with mix and match, with different clinical circumstances and different markets.”

The rush by drugmakers large and small to test GLP-1 rivals means clinical trial data could soon prove which approaches work best.

Already, some companies have been forced to adjust. For example, Pfizer developed two non-peptide oral drugs targeting GLP-1, but both returned mixed results. One was scrapped because of safety concerns. The other remains in testing, but Pfizer is reworking its dosing because of a high rate of gastrointestinal side effects.

Viking Therapeutics has had better luck. The biotech reported encouraging early data for a GIP-GLP1 combination it’s developing as both a shot and a pill. The drug appears more tolerable than Wegovy or Zepound.

A Phase 2 trial of the pill is expected to begin later this year. In the meantime, Viking’s valuation has swelled to around $8 billion, suggesting investors see it as an acquisition target for larger drugmakers looking to build their pipeline.

Zealand Pharma and Boehringer Ingelheim, meanwhile, are partnered on a drug called survodutide that targets GLP-1 and glucagon and has also produced encouraging early results. Phase 3 study data could come late next year.

Investors are also watching closely two drugs from Amgen called AMG 133 and AMG 786. The first activates GLP-1, like Wegovy and Zepbound, but blocks another hormone called GIP — opposite of Zepbound’s mechanism.The big biotech hasn’t disclosed exactly how AMG 786 works.

Regeneron Pharmaceuticals, Biohaven and Lilly are exploring treatments designed to preserve lean mass, results from which could reveal how much this strategy might contribute.

Further afield are companies like Japan’s Shionogi and startups Kallyope and Skye Bioscience. The former drugmaker is working on an inhibitor of an enzyme involved in dietary fat absorption, while Kallyope’s drugs target gut proteins that themselves stimulate hormones like GLP-1. Skye is testing a drug designed to regulate appetite by blocking certain proteins in the nervous system.

Amgen shares soared by double digits in early May following its announcement an obesity drug it’s developing has shown enough promise to warrant advancing into late-stage testing.

On an earnings call with analysts May 3, CEO Robert Bradway said the company is “confident” in the drug’s “differentiated profile” following an internal review of interim Phase 2 study results. Full data are expected by the end of the year and should support a subsequent move into Phase 3 trials, executives said.

Yet Amgen’s drug is likely at least two years away from regulators’ desks, by which time Eli Lilly and Novo Nordisk may already have successors to their weight loss medicines Wegovy and Zepbound. It will take even more time to accumulate data to prove the drug can protect heart health, a key claim for convincing commercial and federal insurers to reimburse for treatment.

Amgen’s market capitalization swelled $20 billion following the announcement, a surge that reflects intense investor interest in emerging weight loss medicines.

The biotech’s lead drug, called maridebart cafraglutide or MariTide, acts on the same targets that Zepbound does, hormones called GLP-1 and GIP. But unlike Zepbound, MariTide blocks, rather than stimulates, GIP. Amgen also aims to show the drug can effectively cut weight with a once-monthly shot, instead of the weekly injections required for Zepbound and Wegovy.

But there’s little known publicly about the drug’s potential.

“We've just seen really a small amount of data. So probably anything is possible and, like you, we will be interested to see their results,” said Lilly’s top scientist, Daniel Skovronsky said on an earnings call earlier this week. “We've placed our bets, and we like the data we got.”

Amgen, though, is now expressing enough confidence to warrant making a substantial investment in late-stage studies. During the May 3 conference call, executives didn’t disclose specific data, but said all 11 study arms of the two-stage, placebo-controlled trial remain active. They also said there “has not been an issue” with patients stopping treatment due to side effects.

The trial enrolled people with obesity or who are overweight and have another health condition. Diabetics were tested separately to better understand the drug’s effects on people with the disease.

Amgen executives have viewed the interim data, but trial investigators and participants are still “blinded” to preserve the trial’s scientific integrity, they said. The company is stopping work on another obesity drug prospect, AMG 786, as early data showed it doesn’t have the same potential as MariTide.

Should MariTide advance into Phase 3, it would likely need to be tested in a trial lasting more than a year, just as Wegovy and Zepbound were. To be competitive, Amgen also will need run the type of large, multiyear trial that can prove whether MariTide protects heart health.

In the meantime, Novo and Lilly will be able to further entrench their drugs on the market. Already, they’ve made significant inroads, with Wegovy recording $1.3 billion in sales in the first quarter and Zepbound $517 million. Both are also seeing prescription numbers climb and are investing heavily in manufacturing.

In addition, both Novo and Lilly are nearing Phase 3 readouts for successor drugs, which, if positive, could raise the bar for would-be competitors.

“I think they will remain the dominant players — not only given existing leadership position but also because of the rebate wall they have constructed,” Umer Raffat, an analyst with Evercore ISI, wrote in a note to clients.

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An experimental pill developed by Novo Nordisk helped people with obesity lose 13% of their body weight after three months of treatment in a small clinical trial, the company said March 7, in a result one analyst described as among the best of any weight loss drug tested so far. 

The drug, called amycretin, is one of a handful of medicines Novo hopes can build on the success of its fast-selling obesity drug Wegovy. Unlike Wegovy, amycretin stimulates two gut hormones, GLP-1 and amylin, that affect appetite and blood sugar levels. It’s also taken orally, not via injections. 

The announcement comes as Novo looks to stave off a laundry list of competitors in a market Wall Street analysts expect to skyrocket in the coming years. Eli Lilly has already won approval of one such medicine, Zepbound, and a number of other large and small companies are advancing other prospects. Leerink Partners forecasts $158 billion in total yearly obesity drug sales in 2032.

Novo’s data are from a Phase 1 trial testing multiple doses of its drug against a placebo in 144 people. The results, disclosed at a March 7 investor presentation, only involved a group of 16 people on an unspecified dose. 

According to Novo, those who received a placebo lost 1% of their body weight over 12 weeks, meaning its drug was associated with placebo-adjusted weight loss of about 12% during the evaluation period. 

That measurement was “exploratory,” and thus didn’t meet the criteria for statistical significance. Comparing drugs across trials is also fraught with potential caveats. Nonetheless, the findings reverberated through the sector, as each development in the obesity drug chase is being closely watched by investors and analysts looking to see how each new medicine might measure up. 

Neither Wegovy nor Zepbound, for instance, were associated with more than 10% weight loss after 12 weeks in the studies underlying their approvals. A newer drug Novo’s working on, CagriSema, helped obese people lose 17% of their body weight at 20 weeks, while an injectable from Viking Therapeutics was associated with 15% weight loss in 13 weeks. 

A pill Lilly has in Phase 3 testing, meanwhile, hit 13% weight loss at 26 weeks. Structure Therapeutics’ experimental pill produced 5% weight loss in an early trial. 

Novo’s new results, then, are “at the highest end of weight loss seen” in testing of obesity drugs, wrote ISI Evercore analyst Umer Raffat. They also caused Novo’s Denmark-traded stock to surge, while shares of Viking, which is also developing an oral weight-loss medicine, fell.

However, Raffat cautioned that, if amycretin were to get to market, Novo could be limited by its manufacturing capacity. High doses of amycretin would require as much as 1 billion milligrams a week — far more than Novo currently produces — to meet the current demands of the U.S. market alone.

An experimental Roche drug helped people with obesity lose an average of nearly 19% of their body weight over six months, after adjusting for placebo, in an early-stage trial, the company said May 16.

Roche is awaiting additional data from a study of the drug, called CT-388, in people with diabetes as well as obesity. It also didn’t provide specifics on the drug’s side effect profile. CT-388 is currently only in a Phase 1 program involving 96 people. Larger and longer trials are needed before the company can ask the Food and Drug Administration for approval.

Roche acquired CT-388 through a $2.7 billion acquisition of biotechnology startup Carmot Therapeutics in December. The deal was part of a rush by pharmaceutical companies to capture a share of a market estimated to be worth more than $100 billion annually by early next decade.

Though it can be difficult to compare drugs across trials, the weight loss figures Roche revealed surpassed what’s been observed in early testing of all other obesity therapies after around six months of treatment, Evercore ISI analyst Umer Raffat wrote in a May 16 note to clients. However, that data would need to be duplicated in bigger trials before it’s clear how well CT-388 stacks up against other drugs.

Roche will also need to show that CT-388 is at least as safe as its rivals. In a statement, the company only said that CT-388 “demonstrated a safety and tolerability profile consistent with its drug class,” which often includes gastrointestinal side effects.

Nonetheless, despite the tough competition, the data suggest that Roche has a chance to gain share of an already lucrative and still growing market.

Novo Nordisk’s Wegovy and Eli Lilly’s Zepbound are the leaders, with sales of $4.5 billion and $176 million respectively last year. Roche aims to position CT-388 as a possible rival to both of them, as the drug is also a weekly injection and, like Zepbound, stimulates two metabolic hormones called GLP-1 and GIP.

Yet it will take time for Roche to catch up. Already, Novo has shown Wegovy can reduce their risk of heart attacks, stroke and cardiovascular-related death in obese people with heart disease. That finding has cleared the way for Medicare to begin covering the drug for some people. Lilly could soon follow, too, with a similar trial due to report data later this year.

Roche has other threats to contend with, too. Many obesity drugs are in mid- or late-stage testing, among them medicines from Boehringer Ingelheim, Pfizer, Amgen, Structure Therapeutics and Viking Therapeutics. Novo and Lilly are also developing oral medicines and other follow-on drugs.

Metsera, a richly funded biotechnology startup, launched in mid-Paril with a portfolio of weight loss drugs the company claims could eventually compete with market-leading medicines from Novo Nordisk and Eli Lilly.

In its first official announcement, the biotech said it has two therapies in clinical testing already. Another “handful” could join in the next year, CEO Clive Meanwell said in an interview.

The biotech has raised $290 million in funding, led by co-founding investment firms Arch Venture Partners and Population Health Partners. It’s already used some of that cash to build a drug portfolio of oral and injectable drugs as well as prospects that simultaneously target multiple gut hormones.

Like many others in the industry, Meanwell was struck by the success of Lilly’s Mounjaro and Novo’s Wegovy, which proved so effective in testing that their makers have struggled to keep up with demand.

Analysts now project a market worth more than $100 billion, a prize that’s sparked a gold rush among large and small companies to follow in Lilly’s and Novo’s footsteps.

Meanwell, an industry veteran who sold his last company to Novartis for nearly $10 billion, also acknowledged the high bar set by Mounjaro and Wegovy. Developing equivalently effective drugs is the “table stakes” for any aspiring competitors, he said.

With the help of Arch and the venture firm, Population Health, that he chairs, Meanwell put together an investor syndicate, raised an unusually large bankroll, and used it to scour the globe for weight loss therapies. The goal was to create a startup that could “go after the second, third, or even fourth generation” of obesity medicines — the ones that might eventually supplant Mounjaro and Wegovy, he said.

“The first generation of products are a godsend,” said Arch managing director Kristina Burow. But people “are going to need different drugs” to cut weight without also losing muscle mass or dealing with side effects, she added. “There is room for more than two players.”

Metsera wants to become one with a portfolio strategy that most companies outside of Lilly and Novo aren’t pursuing, according to Meanwell. With the $290 million it raised, the company acquired U.K.-based biotech Zihipp and formed a licensing pact with Korean drugmaker D&D Pharmatech. The former deal gave it a library of drug prospects targeting different gut hormones. The latter involved a technology capable of making oral versions of those drugs. The company’s done other smaller deals as well, but Meanwell wouldn’t provide specifics.

The resulting pipeline includes an injectable GLP-1 drug like Wegovy with a prospect that, like Lilly’s experimental retatrutide, targets three gut hormones. Metsera also has a two-pronged medicine that stimulates amylin and so-called calcitonin receptors as well as multiple oral candidates.

The company views these, as well as other undisclosed programs, as the components of potential drug combinations. According to Meanwell, animal studies have suggested some of Metsera’s medicines may have superior characteristics — such as longer-lasting effects — than existing drugs.

That hasn’t yet been proven, though, and Metsera may have to catch more advanced competitors to succeed. Phase 1 trials are underway for its GLP-1 drug as well as a second candidate. Others will follow shortly, with multiple study results coming later this year and early next.

“If everything stopped today, if all we had were the existing products on the market, we would have made a tremendous impact,” Burow said. “But because we're biotech, we want to do more. We want to go farther.”

Eli Lilly plans to spend another $5.3 billion building production capacity for its popular obesity and diabetes drugs, responding to immense demand for the medicines with what it claims is now the largest investment of its kind in U.S. history.

The commitment announced by Lilly May 24 adds to $3.7 billion the drugmaker already planned to invest in a manufacturing site it’s constructing in Lebanon, Indiana, some 30 miles from its corporate headquarters in Indianapolis.

The site will help Lilly make the active drug ingredient tirzepatide, which is in its weight loss shot Zepbound and diabetes treatment Mounjaro. Despite pressing hard to expand manufacturing capacity, Lilly has so far had trouble keeping the drugs in steady supply. Certain dose strengths of both products are currently listed as in shortage by the Food and Drug Administration, with limited availability at least through the end of June.

Clinical trial results have proven tirzepatide to be powerfully effective at managing blood sugar in people with diabetes, and for shedding pounds in people who are obese or overweight. Studies conducted by Lilly’s rival Novo Nordisk, meanwhile, have indicated that drugs of this type — so-called GLP-1 agonists — hold benefits for the heart and kidney, too. The companies are also testing their respective medicines in other associated conditions, from sleep apnea to a common liver disease called MASH.

The cumulative result has been a revolution of sorts in how physicians think about treating people with diabetes or obesity, and soaring consumer interest in Lilly’s and Novo’s drugs.

The companies have made significant investments in manufacturing to keep up, both by building new facilities and by buying existing sites. Novo, for example, acquired three plants from its parent Novo Holdings as part of a $16.5 billion deal by the latter company to buy the large contract drugmaker Catalent. More recently, Lilly agreed to acquire a site from Nexus Pharmaceuticals.

All told, Lilly has committed over the past four-and-a-half years to spend more than $18 billion on building, refitting and acquiring drug factories in the U.S. and Europe. Much of that spending has yet to take place, but already Lilly’s annual capital expenditures are at a 10-year high.

The company said the Lebanon facilities will employ 900 full-time staff when they are fully operational. It expects to begin making medicines there toward the end of 2026 and scaling up through 2028.

Lilly reported $1.8 billion in sales for Mounjaro over the first three months of 2024, and $517 million for Zepbound. Even with ongoing supply issues, the company raised its revenue forecast for the year by $2 billion in anticipation of rising sales for the two drugs.

Analysts expect Zepbound and Novo’s rival Wegovy to become some of the best-selling drugs in the pharmaceutical industry and are penciling in peak yearly sales for the broader GLP-1 class as high as $100 billion.

Fresh clinical trial results for Eli Lilly’s drug Zepbound point to a new use for the weight loss medicine in treating a common sleep disorder, adding to evidence the benefits of so-called GLP-1 agonists could extend across a range of conditions.

Zepbound, which is known scientifically as tirzepatide, significantly reduced episodes of obstructive sleep apnea in overweight or obese participants in two late-stage studies run by Lilly. The drug was effective in people who used a breath device that prevents the airway collapse characterizing the disorder, as well as those who didn’t.

Sleep apnea is associated with obesity, and weight loss has previously been shown to help sleep apnea symptoms.

In one Phase 3 trial of people who weren’t using the breathing devices — called continuous positive airway pressure, or CPAP machines — Zepbound reduced the average hourly number of sleep apnea events by 27, or 55%, after one year, compared with a reduction of five for those given a placebo.

In the second Phase 3 study of people on CPAP machines, Zepbound reduced the average number of hourly sleep apnea events by 30, or 63%, compared with an average of six for those who received a placebo.

People treated with Zepbound in the non-CPAP trial lost 18% of their body weight, while those in the CPAP study lost 20%. Participants on placebo in the studies lost 1% or 2% of their body weight, respectively.

Lilly said it plans to submit the data to the Food and Drug Administration, which has granted the drug Fast Track designation in sleep apnea and obesity, as well as to other drug regulators beginning mid-year. Fuller data from the trials will be revealed at the American Diabetes Association annual meeting in June and published in a medical journal.

The study findings come as Lilly and GLP-1 rival Novo Nordisk seek to expand the use of their weight loss drugs into disorders that arise from obesity and metabolic dysfunction.

Novo recently won FDA approval to begin marketing its drug Wegovy for heart protection after results from a large Phase 3 trial showed it could reduce cardiovascular risk in people with obesity or who were overweight and had heart disease. That data led the U.S. government’s Medicare program for the elderly and disabled to begin covering the drug for some enrollees.

Lilly may not have similar data until 2025.

Wegovy has also show it can ease symptoms of heart failure in people with obesity. Both Novo and Lilly have tested their drugs in the obesity-related fatty liver inflammation disorder known as MASH, with positive mid-stage data reported so far from both.

Zepbound is sold under the brand name Mounjaro for use in treating diabetes.

An experimental obesity drug from Boehringer Ingelheim and Zealand Pharma succeeded in a mid-stage liver disease study, the latest evidence new weight loss medicines could also help people with metabolic dysfunction-associated steatohepatitis, or MASH.

Summary results disclosed Feb. 26 showed that up to 83% of trial participants treated with the companies’ drug, survodutide, experienced a significant improvement in their disease without worsening liver scarring, compared to about 18% of those given placebo. The drug met its secondary study goals, notably demonstrating a benefit on liver scarring, the companies said.

In recent years, drugs known as incretins have become the industry’s most coveted products, proving able to treat diabetes, help people to lose weight and even protect heart health.

Clinical trial results like those from Boehringer and Zealand are now indicating incretins may play a role treating MASH, a disease estimated to affect millions of people and one of the leading causes of liver transplants.

MASH is caused by a toxic build-up of liver fat, and often develops alongside other metabolic diseases like diabetes. While it has long been a top drug target, it’s proven difficult for companies to crack. Several promising prospects have failed in advanced testing and the first to reach regulators — a medicine from Intercept Pharmaceuticals — was rejected last year.

A newer crop of medicines has followed. A MASH drug from Madrigal Pharmaceuticals won regulatory approval in March, for example. Other medicines from Akero Therapeutics and 89bio have shown some promise, too, though study results haven’t been as clear.

Yet they could be undercut by incretins. In February, Eli Lilly said tirzepatide, the drug it sells as Zepbound for weight loss, met its goal in a Phase 2 MASH study. At the time, Raymond James analyst Steven Seedhouse described the findings as the “best any [MASH] drug has ever shown in Phase 2 or Phase 3.”

Boehringer and Zealand’s drug, survodutide, may be another competitor. The drug, which the two companies are also developing for obesity, works somewhat differently than tirzepatide or Novo Nordisk’s Wegovy. Like those drugs, survodutide activates an insulin-regulating hormone called GLP-1. But the drug also targets a receptor controlling the hormone glucagon, which could be useful for treating MASH because it increases the liver’s metabolic rate.

The summary results disclosed so far are “roughly in line” with what Lilly reported, which may “lead to some pressure on [MASH]-focused companies,” Leerink Partners analyst Thomas Smith wrote in a client note.

But he and Jefferies analyst Michael Yee highlighted several caveats that make the findings harder to interpret. While comparing drugs across trials is difficult, Boehringer’s study had “less stringent” goals than the endpoints used by Lilly and others, Yee wrote. The company also enrolled a healthier study population, while its bar for declaring a liver scarring improvement is lower than in other trials, he added.

Fuller safety data are also needed to properly assess the results, Smith wrote.

Three Phase 3 studies of survodutide are underway in obesity. Results could come in 2025 and 2026, according to a federal database.