Eli Lilly Set to Overtake Novo Nordisk in Weight-Loss Drug Race by 2025

By the end of 2025, Eli Lilly and Co. is poised to surpass Novo Nordisk A/S as the dominant force in the global weight-loss drug market — a seismic shift just three years after Novo Nordisk seemed untouchable. The turning point? A $10 billion quarter. In Q3 2025, Eli Lilly’s dual-action therapies Mounjaro and Zepbound, both containing tirzepatide, smashed expectations, pulling in more than $10 billion in combined sales. Meanwhile, Novo Nordisk’s flagship drugs, Ozempic and Wegovy, generated just under $8 billion in Q2 — a figure that, while still massive, now feels like the beginning of a slowdown rather than a surge.

The Rise of Tirzepatide

Here’s the thing: Eli Lilly didn’t just get lucky. It bet big on a drug that does two things at once — lowers blood sugar and triggers profound weight loss. Tirzepatide, the active ingredient in both Mounjaro and Zepbound, works on two receptors in the body (GLP-1 and GIP), while Novo Nordisk’s semaglutide (in Ozempic and Wegovy) targets just one. That dual-action edge isn’t just science jargon — it’s translating into real patient preference. Doctors are reporting more patients asking for Zepbound by name. Some who started on Ozempic are switching. And those switching? They’re losing more weight, on average.

Novo Nordisk’s Perfect Storm

But wait — Novo Nordisk isn’t collapsing. It’s being squeezed from every side. The company has cut its 2025 financial guidance twice this year. Why? Supply bottlenecks for Wegovy are real. Patients can’t get it. So they turn to compounded semaglutide — cheaper, unregulated, and growing fast. Meanwhile, investor confidence took a hit after disappointing trial results for CagriSema, Novo’s next-gen obesity drug, were presented in March 2025. The data? Underwhelming. Shares plunged 50% year-to-date as of August 6, 2025, and still hadn’t recovered by November.

Even its sales numbers tell a story of slowing momentum. Analysts now forecast Ozempic sales to grow just 7% in 2025 — down from 26% in 2024. Wegovy’s growth is holding at 40%, but that’s expected to drop to 25% next year. Novo Nordisk’s entire diabetes and obesity portfolio, once a cash cow growing at 26%, is now projected to rise just 10% to $46.5 billion in 2025.

Manufacturing vs. Morale

Eli Lilly, by contrast, is going all-in on capacity. The company spent over $5 billion in 2024 expanding manufacturing and plans to invest another $10 billion in 2025. It’s signed contracts worth up to $14 billion with global producers to lock in supply. That’s not just ambition — it’s a declaration of war on scarcity. Meanwhile, Novo Nordisk’s internal battles are growing louder. The Novo Nordisk Foundation, which controls 77% of voting rights, pushed for board restructuring. Shareholders pushed back. The tension reveals a deeper unease: even the foundation, long seen as a stabilizing force, is worried about the future.

What Patients and Traders Are Saying

It’s not just Wall Street that’s turning. On Stocktwits, a retail investor forum, a poll of 3,300 traders in November 2025 showed 32% named Eli Lilly as the obesity-drug stock they were most bullish on over the next five years. Novo Nordisk and Hims & Hers Health tied at 26%. That’s not a fluke. It’s a signal. Patients are feeling the difference. Traders are betting on it. And the numbers are catching up.

Even Novo Nordisk’s recent announcement of an oral semaglutide 25 mg formulation — promising weight loss and cardiovascular benefits comparable to Wegovy — hasn’t sparked the same excitement. Why? Timing. The market’s already moved on. Eli Lilly’s supply chain is scaling. Novo Nordisk’s is still playing catch-up.

The Bigger Picture

This isn’t just about two drugmakers. It’s about how quickly medical innovation can shift. Just five years ago, Novo Nordisk was the poster child for biotech dominance. Now, it’s a cautionary tale of what happens when a company underestimates competition, overpromises on supply, and fails to adapt fast enough. Eli Lilly didn’t invent GLP-1 drugs. But it built something better — and made sure the world could get it.

The broader medical sector has been rough in 2025. Many biotech stocks fell. But Eli Lilly? Up 21% year-to-date. Novo Nordisk? Down 43%. That divergence isn’t random. It’s the market voting with its dollars.

What’s Next?

Expect more pressure on Novo Nordisk’s pricing power. Insurance companies are already pushing back on high list prices. Eli Lilly’s cheaper, more reliable supply could force concessions. Meanwhile, Eli Lilly’s next targets? A once-weekly oral version of tirzepatide and combination therapies with other metabolic agents. The race isn’t over — but the momentum has clearly shifted.