Eli Lilly Is Up 58%, Novo Is Down 62%: One Number Shows Why the GLP-1 Race Changed

Market share explains the widening gap between Eli Lilly and Novo Nordisk

This is no longer a simple "both win" GLP-1 story.

The number that changed the race

Eli Lilly has taken the bigger prize in obesity: 60% share of global prescription obesity revenue. Together, Lilly and Novo Nordisk still dominate the category, controlling about 87% of global prescription obesity drug revenue. That concentration matters because obesity is the faster-growing part of the GLP-1 market, which reached $66 billion in 2025.

The stock divergence reflects that shift. Lilly is up 13.4% this year and 58% over the past 52 weeks. Novo Nordisk is up just 0.4% year to date, down 5% over the past 52 weeks, and still off 62% since July 2024. The market is not treating the two companies as equal beneficiaries of growth anymore; it is pricing Lilly as the current leader in the segment expanding most quickly.

That market could keep expanding fast: Bloomberg sees obesity treatment reaching $120 billion by 2030. In 2026, another shift is adding complexity. The conversation is moving from injections toward pills, with Novo's first GLP-1 pill for obesity already available and Lilly's oral option expected to get U.S. approval later this year. For now, Lilly's lead is built on current sales and share; Novo's clearest near-term path to catch up runs through oral treatment.

Why Eli Lilly's lead has widened

Lilly's advantage is not abstract. It shows up in sales, clinical comparisons, and the broader narrative around who is winning the obesity market.

Lilly has built commercial momentum

In the first quarter of 2026, Zepbound generated $4 billion in sales versus $2.7 billion for Wegovy. That matters because obesity treatment is recurring therapy, not a one-time sale. The more a drug is prescribed and the longer patients stay on it, the harder it becomes for rivals to displace.

Lilly still holds the potency edge in the latest head-to-head data

In Novo's own 84-week trial, CagriSema produced 23% weight loss, while tirzepatide reached 25.5%. That is not a disproof of Novo's pipeline, but in a market where clinicians and payers focus on outcomes, even a small difference can influence choice at scale. At this point, Lilly still appears to hold the edge on peak efficacy.

Lilly is also shaping the public debate

Novo is suing Lilly in U.S. federal court, alleging false advertising in how Zepbound and Mounjaro are pitched. Lilly has said its advertising is truthful and based on the most direct evidence available. Either way, the dispute has reinforced the perception that Lilly currently controls more of the market conversation.

Obesity pills are the next test for both companies

The next catalysts are straightforward:

• Lilly's next major rerating test is an oral launch. A U.S. approval later this year would matter because pills could attract entirely new patients and broaden access beyond injections.
• Novo still needs to show that oral delivery can protect its share and narrow Lilly's lead, not just open a new way to administer treatment.

For now, market share remains the clearest bridge from current sales to future earnings power. On that measure, Eli Lilly is ahead.