More Than Numbers on the Scale: A Future Focused on Quality of Weight Loss

Regeneron leaders on what quality of weight loss means for people living with obesity, and what it will take to get there.

Regeneron

September 21, 2026

Advancements in the understanding of obesity and how to treat it have shifted fundamentally in recent years. Once viewed largely as a matter of individual choice, obesity is now understood as a complex, multifactorial disease that demands treatments that go beyond the scale.

However, significant unmet needs remain for both patients and clinicians.

Current therapies have made significant, rapid weight loss possible, but that may not always address the full picture. There is growing evidence that effective treatment means also considering: associated conditions, muscle mass preservation, functional health, treatment sustainability and overall quality of life. In essence, moving from the quantity of weight loss to the quality of weight loss and its broader potential health benefits.

Below, a few of our Regeneron leaders reflect on what success could look like in this new era of obesity treatment.

Q: While advancements in obesity treatment have been significant, what do you see as the biggest opportunities to continue to improve outcomes and the patient experience?

Boaz Hirshberg, SVP, Clinical Development Unit Head, Internal Medicine:

When I would see patients 20 years ago, obesity was often viewed as a choice or the fault of the patient. Now that we have a better understanding of how biology and metabolism drive obesity and cardiometabolic diseases, we know that obesity is not such a choice.

Advancements in treatments have thankfully shifted this perspective, but the initial treatment focus started on the quantity of weight lost rather than the quality and its broader health benefits.

Obesity is linked to many different types of conditions including Type 2 diabetes, heart disease and others. Effective weight loss has the potential to improve these conditions or reduce the risk of developing them in the future and it opens the door to combination therapies that address conditions like dyslipidemia, alongside obesity.

Our research has also confirmed that rapid weight loss can cause significant muscle loss alongside fat loss. Phase 2 data showed that approximately 35% of GLP-1-induced weight loss was due to lean mass loss, a critical finding that reframes how we must think about therapeutic success—and why we should consider the quality of weight loss and its broader health benefits.

Q: What makes Regeneron uniquely positioned to pursue advancements in the understanding and treatment of obesity?

Mark Sleeman, VP, Head of Obesity, Muscle and Metabolism Research:

Over the past 40 years, we’ve made significant discoveries in appetite regulation, metabolism, lipids and muscle biology. For example, early, sustained research efforts on GDF8 and Activin-A revealed fundamental mechanisms of skeletal muscle growth and loss, with potential applications for obesity.

Genetics is embedded in everything we do at Regeneron. Our efforts are accelerated by ongoing research through the Regeneron Genetics Center (RGC), where a large, representative genetic database helps us to identify new potential therapeutic targets and validate existing ones grounded in human biology from the earliest stages of research. RGC has a proven track record of using protective human genetics to identify novel therapeutic targets across cardiometabolic disease and beyond.

Q: Is a shift to quality weight loss over quantity necessary if people are losing weight?

Chiedza Kaitano, VP, Global Program Head, Obesity:

We are undeniably in a new era of obesity treatments with an absolute whirlwind with unprecedented progress.

However, quality of weight loss is more than just the number on the scale. The question is no longer just ‘can we achieve significant weight loss?’ The next era will need to focus on responsible, durable weight management that patients can maintain—not just rapid results.

As we continue to advance therapies, we must consider critical dimensions like maintaining muscle, since muscle loss has the potential to negatively impact long-term metabolic health, physical function and a person’s ability to sustain weight loss over time. Our focus must be on trying to address the root causes of obesity, with the goal of sustainable, long-term outcomes that preserve functional health and improve quality of life.

This shift will require therapies that can be tailored to individual patient needs to improve long-term health outcomes.

Q: Given how many treatments are already available, why are more needed?

Robert Pordy, VP, Cardiovascular & Metabolism Therapeutics:

No single molecule can address the full heterogeneity of obesity or the diverse needs of patients. Because obesity is such a complex disease, existing therapies may not be able to address every patient's needs.

For example, we know obesity is linked to Type 2 diabetes, hypertension, coronary artery disease and many other conditions. As we continue to advance treatments, there is an opportunity to investigate novel combinations that can help address associated conditions alongside obesity.

Redefining What Success Looks Like

Success in obesity treatment won't be measured by the number on the scale alone, but by whether patients can sustain their health, their function and their quality of life over the long term. This is the new era Regeneron is working to define.

Check out The Science of Obesity: Regeneron’s Research on Genetics, GLP-1s and Quality Weight Loss on YouTube.