The Weight Loss Drug Battle Is Entering a Whole New Phase After ADA

The latest American Diabetes Association (ADA) conference made one thing clear — the weight loss drug race is no longer just about losing the most pounds. The game has shifted toward better tolerability, long-term results, and smarter combinations. And with global obesity numbers climbing, the next generation of treatments is moving into place.

As blockbuster drugs like Wegovy and Zepbound head toward patent cliffs, more than 150 companies are vying for a slice of a market Morgan Stanley says could hit $150 billion by 2035. What’s coming isn’t just more of the same — it’s a full-on rethinking of how we approach obesity, using new hormones, better delivery systems, and smarter science.

Beyond GLP-1 What’s Next in the Pipeline

Right now, GLP-1 drugs dominate the market. These drugs mimic a gut hormone that helps regulate appetite and blood sugar — and they’ve already helped millions lose weight. $NVO’s Wegovy and $LLY’s Zepbound are the two giants here.

Zepbound currently leads in data: 20.9% average weight loss versus Wegovy’s 17% at the same 2.4 mg dosage, and a 75% fat loss rate versus 61%. That helped Lilly take market share at the end of 2024, pressuring Novo to respond.

But GLP-1 drugs have limits — side effects like nausea, the need for injections, and variable patient response. That’s why the industry’s attention is turning to the next wave: amylin receptor agonists, which mimic a different hormone produced by the pancreas.

These new candidates could be gentler on the body and more targeted in how they affect fat metabolism and appetite. That combination of effectiveness and tolerability is exactly what researchers — and patients — are hoping for.

The Amylin Push Is Heating Up

So what exactly is amylin? It’s a naturally occurring hormone that works alongside insulin to help manage appetite and slow stomach emptying. Drugs built on this hormone may offer weight loss benefits similar to GLP-1s, but with fewer side effects and greater patient comfort.

At this year’s ADA conference, several companies made clear they’re betting big on this new pathway:

• Novo Nordisk($NVO) is working on a combo drug called CagriSema (semaglutide + amylin analogue) and higher doses of Wegovy. One recent trial showed 21% weight loss after 72 weeks, with one-third of participants losing over 25%.

• Eli Lilly($LLY) is diversifying with oral GLP-1 drugs like Orforglipron, plus Bimagrumab and other agents targeting fat metabolism.

• AstraZeneca($AZN) presented AZD6234, a long-acting amylin analogue now in Phase 2.

• Zealand Pharma, in partnership with Roche, is advancing Petrelintide in a licensing deal worth up to $5.3 billion.

What connects all of these? The focus is shifting from just losing weight to doing it in a way that patients can stick with — safer, longer, and ideally, through easier delivery like pills instead of injections.

Why This Market Is More Than Just a Fad

This is not just another biotech boom. Obesity is now recognized globally as a chronic disease — not just a lifestyle issue. According to the World Health Organization, over one billion people worldwide are obese, and about one in three of those also have type 2 diabetes or prediabetes.

That makes obesity not just a weight issue, but a public health time bomb — driving up risks for heart disease, cancer, liver disease, and more. That’s why governments, insurance systems, and drugmakers are all looking for better long-term options.

It’s also why Morgan Stanley’s projection of a $150 billion market doesn’t seem unrealistic. If anything, this could become the largest new category in global pharmaceuticals since oncology.

What Matters Most in the Next Phase

The weight loss race is no longer about who slims down the fastest. It’s about sustainability, access, and personalization. Here are three trends to watch:

1. Oral treatments are the next big battleground. The move from weekly injections to daily pills could be a game-changer for patient uptake and market size.

2. Chronic disease bundles. Many companies are exploring how to combine obesity treatment with therapies for diabetes, heart disease, or high cholesterol — making these drugs more appealing to payers and health systems.

3. Post-treatment stability. One major concern now is “rebound weight gain” after stopping a drug. The companies that figure out how to extend results or taper off without relapse will have a huge edge.

Final Thoughts

The future of weight loss drugs isn’t just thinner bodies — it’s better health, better adherence, and smarter integration into chronic care.

The companies that can blend strong clinical results with real-world use — tolerability, delivery, duration — will be the ones that define this next era.

This isn’t just about appetite anymore. It’s about innovation, systems thinking, and building a platform for long-term health.

We’re past the first wave of weight-loss hype. What comes next will be a lot more complex — and a lot more impactful.