Korean and US experts say Wegovy is redefining obesity care, but access is key

Novo Nordisk has long pioneered advances in diabetes care, and with more than 25 years of research in obesity, it has helped redefine the condition as a treatable chronic disease.

Building on this background, the company’s once-weekly semaglutide injection Wegovy is regarded as a milestone therapy with proven efficacy in both Western and Asian patients.

On the sidelines of the International Congress on Obesity and Metabolic Syndrome (ICOMES 2025) in Seoul, Korea Biomedical Review sat down with Professor Steven E. Kahn of the University of Washington and Professor Lim Soo of Seoul National University Bundang Hospital to discuss how Wegovy is reshaping obesity care, what recent trial results mean for Korean patients, and how access challenges may affect its broader adoption.

From symptom to chronic disease

Both experts stressed that obesity should no longer be dismissed as a matter of lifestyle or willpower.

Kahn emphasized that obesity has become one of the most pressing global health threats, affecting younger populations in Korea as well as worldwide. He noted that it is now climbing the list of global health priorities alongside other non-communicable diseases, demanding rapid responses.

Lim highlighted the Lancet Commission’s new diagnostic framework that moves beyond body mass index (BMI) alone and includes clinical abnormalities and daily functional limitations. With 76 institutions worldwide agreeing on this definition, Korea among them, Lim argued that this shift allows obesity to be seen alongside diabetes, hypertension, and dyslipidemia as a disease rather than a personal failing.

“When patients are recognized within the medical system,” he said, “they gain both treatment rights and better access to medications.”

Still, BMI remains widely used in clinics due to its simplicity. But Kahn pointed out that in Asian populations it can be misleading. Many patients who appear slim carry dangerous visceral fat that only imaging can reveal, while others with high BMI do not exhibit metabolic problems.

Lim added that waist circumference, body fat percentage, and laboratory markers such as blood glucose and lipid levels are increasingly necessary for accurate diagnosis.

This reconceptualization of obesity has opened the door for new therapies.

Wegovy, developed initially for type 2 diabetes, has shown not only significant weight loss and glucose reduction but also broader systemic effects, including reduced inflammation and protection of the heart and kidneys.

These pleiotropic benefits explain why GLP-1 therapies are now prescribed across multiple specialties, from endocrinology to cardiology and family medicine.

Beyond weight loss: long-term health and access challenges

The clinical evidence for Wegovy has redefined expectations in obesity care.

The SELECT trial showed that Wegovy reduced major cardiovascular events in overweight or obese patients without diabetes but with heart disease. It also demonstrated a 75 percent lower risk of progressing to type 2 diabetes.

“This was the first trial proving cardiovascular protection in this group,” Kahn said, calling it a paradigm shift.

Lim pointed to the STEP 11 trial, the first to apply Asia’s BMI threshold of 25 kg/m².

Conducted in Korean and Thai patients, it demonstrated a 16.1 percent average weight reduction, confirming the drug’s effect in Asian populations. “For Koreans,” Lim noted, “this proves the drug is effective even in those who might not meet Western BMI thresholds.”

Other trials have further shaped the picture.

The LEADER trial showed cardiovascular benefits of liraglutide, though with less weight reduction than semaglutide. By contrast, tirzepatide, another emerging GLP-1/GIP dual agonist, has reported superior weight loss in studies such as SURMOUNT.

But Kahn cautioned against assuming equivalence.

“Semaglutide has robust cardiovascular outcome data already, while tirzepatide is still collecting evidence,” he said. “Until we see more, they cannot be considered interchangeable.”

Both experts stressed that obesity remains a chronic, relapsing disease.

Patients frequently regain weight after stopping therapy, a pattern confirmed in multiple studies. Kahn explained that rebound is not just a cosmetic issue but may accelerate diabetes progression or even raise risks of conditions such as Alzheimer’s disease.

Lim said that when cost forces patients to discontinue, clinicians must push lifestyle reinforcement -- especially protein intake and exercise -- to preserve muscle mass and maintain metabolism.

This highlights another growing debate --muscle loss, or sarcopenia, during weight reduction. Lim noted that while fat and muscle are typically lost in a 70:30 ratio, the impact varies by patient profile.

Severely obese individuals benefit most from fat reduction, but lighter or older Asian patients may face risks if muscle loss is unchecked.

Kahn added that fears of sarcopenia have been amplified on social media in ways reminiscent of past exaggerations about statin side effects.

“Function matters as much as volume,” he said, noting that many patients actually report greater mobility despite losing some lean mass.

Safety concerns about Wegovy have also surfaced, including gastrointestinal discomfort and questions about pancreatitis or thyroid cancer. But large-scale trials have not confirmed these risks in humans.

Kahn said that the balance of evidence strongly favors continued treatment, warning that avoiding therapy because of overstated fears could deprive patients of life-saving benefits.

Long-term sustainability, however, is tied to cost and access.

In Korea, medical societies are in active talks with the government to establish reimbursement for type 2 diabetes, which could pave the way for broader coverage in obesity.

Lim expressed optimism that coverage might begin as early as next year. In the U.S., by contrast, patients face the world’s highest prices and inconsistent insurance coverage. Kahn observed that pharmacy benefit managers (PBMs) complicate the system, with rebates and negotiations that leave many patients unable to access therapy despite its proven efficacy.

He noted that disparities are so stark that some patients travel abroad to purchase the drug at a fraction of the U.S. cost.

As a possible solution mentioned by the two professors, pharmaceutical firms are exploring solutions to improve long-term management.

Research is underway on biweekly or monthly formulations that could reduce patient burden, as well as strategies to taper dosing without triggering weight regain. Such innovations, the professors suggested, may be crucial for ensuring adherence and affordability.

The broader social impact of reframing obesity as a disease is also becoming clearer. With obesity increasingly recognized as a chronic condition, younger patients in Korea who might previously have been overlooked are now seen as requiring early intervention.

Kahn speculated that if treatment is used earlier -- say in a patient in their thirties with a BMI of 35 -- it may be possible to delay the onset of heart attacks or strokes by decades. Lim added that findings from SELECT already suggest that semaglutide could delay the progression of prediabetes by 10 to 20 years.

For now, the message is clear. Obesity is a chronic disease requiring continuous management, and Wegovy offers more than weight loss.

It has demonstrated broad benefits across cardiovascular and metabolic health, validated in both global and Korean populations. The challenge now lies in ensuring that patients can access and sustain therapy, and in integrating lifestyle and medical approaches to secure lasting health outcomes.

As Lim put it, “If cost barriers are addressed, Wegovy has the potential to redefine how we manage obesity in Korea and globally.”