Novo Nordisk vs. Eli Lilly: The GLP-1 Market War
**Two pharmaceutical companies. One drug class. Hundreds of billions of dollars at stake.** Novo Nordisk and Eli Lilly have both built their modern identities around GLP-1 receptor agonists, but after a year of diverging trajectories, the competition between them looks less like a rivalry and more
Two pharmaceutical companies. One drug class. Hundreds of billions of dollars at stake. Novo Nordisk and Eli Lilly have both built their modern identities around GLP-1 receptor agonists, but after a year of diverging trajectories, the competition between them looks less like a rivalry and more like a rout. Here is the full picture — how each company got here, where they stand today, and what happens next.
Table of Contents
- Two Companies, One Origin Story: Insulin
- The GLP-1 Timeline: How We Got Here
- Product Portfolios: Head to Head
- Financial Performance: The 2025 Scorecard
- Market Share: The Shift That Changed Everything
- Clinical Trial Data: Efficacy Face-Off
- Pipeline Comparison: The Next Five Years
- Strategy Differences: Two Roads to the Same Market
- Manufacturing and Supply Chain
- The Pricing Battle
- The Oral GLP-1 Showdown
- Investment Thesis: Which Stock Wins?
- FAQ
- The Bottom Line
- References
Two Companies, One Origin Story: Insulin
Both Novo Nordisk and Eli Lilly trace their GLP-1 empires back to insulin.
Novo Nordisk was born from insulin. In 1922, Danish professor August Krogh visited Toronto, where Frederick Banting and Charles Best had just succeeded in manufacturing insulin. Krogh brought the technology home, and in 1923, Nordisk Insulinlaboratorium was established in Copenhagen. A workplace dispute in 1924 led a fired employee, Thorvald Pedersen, to start a rival insulin company — Novo Therapeutisk Laboratorium — in 1925. These two companies competed fiercely for 64 years before merging in 1989 to form Novo Nordisk A/S, the world's largest insulin producer.
Eli Lilly got to insulin from a different angle. Founded in 1876 by Colonel Eli Lilly in Indianapolis, the company had already built a reputation for quality manufacturing when the Toronto team came calling. In 1922, Eli Lilly partnered with Banting's team to mass-produce insulin, launching Iletin in 1923 as the first commercially available insulin in the United States. In 1982, Lilly produced Humulin — the first commercially available genetically engineered medication — using recombinant DNA to produce human insulin in bacteria.
Insulin did "more than any other" product to make Lilly "one of the major pharmaceutical manufacturers in the world," as the company itself acknowledges. For Novo, insulin was the company. It was the reason both halves existed.
A century later, both companies leveraged that deep expertise in peptide hormones and metabolic disease to dominate the GLP-1 class. But they arrived there through different scientific approaches.
The GLP-1 Timeline: How We Got Here
GLP-1 (glucagon-like peptide-1) is a hormone produced in the gut that stimulates insulin secretion, slows gastric emptying, and reduces appetite. Natural GLP-1 breaks down within minutes in the body. The pharmaceutical challenge was making it last.
Key milestones:
- 2005: Eli Lilly brings exenatide (Byetta) to market — the first GLP-1 receptor agonist. It required twice-daily injections.
- 2010: Novo Nordisk launches liraglutide (Victoza) for diabetes, a once-daily GLP-1 agonist.
- 2014: Novo launches Saxenda (liraglutide for obesity) — the first GLP-1 specifically approved for weight loss.
- 2017: Novo launches semaglutide (Ozempic) for diabetes — a once-weekly injection that changed the market.
- 2021: Novo launches Wegovy (semaglutide for obesity), triggering the mainstream GLP-1 boom.
- 2022: Eli Lilly launches Mounjaro (tirzepatide) for diabetes — a dual GIP/GLP-1 agonist that acts on two hormonal pathways.
- 2023: Lilly launches Zepbound (tirzepatide for obesity), directly challenging Wegovy.
- 2025: Oral semaglutide (Wegovy pill) approved for weight loss. The race for oral GLP-1 dominance begins.
Novo had a five-year head start with Ozempic and Wegovy. Lilly has erased that lead in under two years.
Product Portfolios: Head to Head
Novo Nordisk's GLP-1 Lineup
| Product | Active Ingredient | Indication | Dosing | Mechanism |
|---|---|---|---|---|
| Ozempic | Semaglutide | Type 2 diabetes | Weekly injection | GLP-1 agonist |
| Wegovy (injectable) | Semaglutide | Obesity, cardiovascular risk | Weekly injection | GLP-1 agonist |
| Wegovy (pill) | Semaglutide | Obesity | Daily oral | GLP-1 agonist |
| Rybelsus | Semaglutide | Type 2 diabetes | Daily oral | GLP-1 agonist |
The advantage: Novo owns the semaglutide molecule across multiple formulations and indications. It has the broadest commercial footprint and the longest track record.
The vulnerability: Every product depends on one molecule. If semaglutide loses patent protection or falls behind on efficacy, the entire franchise is exposed.
Eli Lilly's GLP-1 Lineup
| Product | Active Ingredient | Indication | Dosing | Mechanism |
|---|---|---|---|---|
| Mounjaro | Tirzepatide | Type 2 diabetes | Weekly injection | Dual GIP/GLP-1 agonist |
| Zepbound | Tirzepatide | Obesity, obstructive sleep apnea | Weekly injection | Dual GIP/GLP-1 agonist |
The advantage: Tirzepatide's dual mechanism — targeting both GIP and GLP-1 receptors — produces greater weight loss and glycemic control than semaglutide in head-to-head data.
The vulnerability: Lilly has only one approved GLP-1 molecule so far. Its oral candidate (orforglipron) is still awaiting FDA approval.
Financial Performance: The 2025 Scorecard
The numbers from 2025 tell the story in stark terms.
Eli Lilly
- Full-year 2025 revenue: $65.2 billion (+45% vs. 2024)
- Q4 2025 revenue: $19.3 billion (+43%)
- Full-year EPS: $24.21 (+86%)
- Q4 Mounjaro revenue: $7.4 billion (+110%)
- Q4 Zepbound revenue: $4.2 billion (+122%)
- 2026 guidance: $80-83 billion (midpoint implies 25% growth)
Novo Nordisk
- Full-year 2025 revenue: DKK 309 billion / $45.9 billion (+10% CER)
- Full-year Wegovy sales: DKK 28 billion (+134%)
- Full-year operating profit: DKK 127.6 billion / $18.9 billion (+6% CER)
- Q4 2025: Revenue declined 8% year-over-year
- 2026 guidance: Sales growth of -5% to -13% CER
Lilly's market capitalization has ballooned. Novo's has contracted. A year ago, the gap between them was narrower. Today, CNBC reported, the "dichotomy between the two companies' prospects was accentuated" by their back-to-back earnings releases in February 2026.
Market Share: The Shift That Changed Everything
In May 2024, Eli Lilly began gaining share in the U.S. incretin market while Novo started losing it. What looked like a blip turned into a sustained trend.
By the end of 2025:
- Lilly held over 60% of the U.S. incretin market — up from roughly 40% a year earlier.
- Novo's share dropped to about 39% — down from approximately 60%.
- Mounjaro exited Q4 2025 with over 55% of new type 2 diabetes incretin prescriptions.
- Zepbound held nearly 70% of new branded obesity prescriptions.
- Zepbound had overtaken Wegovy in U.S. weekly prescriptions.
This was not a gradual shift. It was a progressive, accelerating move toward Lilly's drugs. As 24/7 Wall Street reported, "Eli Lilly is dominating the GLP-1 wars."
Novo retains a larger global GLP-1 volume market share at 62%, supported by its head start in international markets. But the U.S. accounts for the majority of GLP-1 revenue, and that is where Lilly is winning.
Clinical Trial Data: Efficacy Face-Off
The market share shift maps directly to clinical data. Tirzepatide beats semaglutide in head-to-head studies.
Weight Loss Comparison
| Drug | Trial | Weight Loss (on-treatment) | Duration |
|---|---|---|---|
| Semaglutide 2.4 mg (Wegovy) | STEP 1 | ~15% | 68 weeks |
| Tirzepatide 15 mg (Zepbound) | SURMOUNT-1 | ~22.5% | 72 weeks |
| Oral semaglutide 25 mg | OASIS 4 | ~17% | 64 weeks |
| CagriSema 2.4/2.4 mg | REDEFINE 1 | ~22.7% | 68 weeks |
| Retatrutide 12 mg | TRIUMPH-4 | ~28.7% | 68 weeks |
Tirzepatide's dual GIP/GLP-1 mechanism delivers roughly 20% weight loss compared to semaglutide's 14-15%. That gap — about 6 percentage points — has proven large enough to drive prescribers and patients toward Lilly.
Diabetes Control
In diabetes trials, tirzepatide also outperforms semaglutide on HbA1c reduction, though both drugs are highly effective. Novo's CagriSema combination brought semaglutide-based therapy closer to tirzepatide's efficacy (22.7% weight loss), but it required two molecules to match what tirzepatide achieves with one.
Cardiovascular Outcomes
Both companies have strong cardiovascular data. The SELECT trial showed Wegovy reduced major adverse cardiovascular events (MACE) by 20% in patients with obesity and established cardiovascular disease. Lilly's SURPASS-CVOT and SURMOUNT-MMO cardiovascular outcomes trials for tirzepatide are still reading out, with results expected to further shape the competitive picture.
Pipeline Comparison: The Next Five Years
The pipeline race may matter more than current products for determining who wins the 2027-2030 market.
Novo Nordisk Pipeline
| Candidate | Mechanism | Stage | Projected Weight Loss |
|---|---|---|---|
| High-dose semaglutide 7.2 mg | GLP-1 agonist | FDA decision Q1 2026 | Improved vs. 2.4 mg |
| CagriSema | Semaglutide + amylin analogue | Filing expected early 2026 | ~22.7% |
| Amycretin (subcutaneous) | GLP-1/amylin dual agonist | Phase 3 starting 2026 | ~22% (Phase 2) |
| Amycretin (oral) | GLP-1/amylin dual agonist | Phase 3 starting 2026 | TBD |
| Oral semaglutide 50 mg | GLP-1 agonist | Phase 3 | TBD |
Eli Lilly Pipeline
| Candidate | Mechanism | Stage | Projected Weight Loss |
|---|---|---|---|
| Orforglipron | Oral non-peptide GLP-1 agonist | FDA review, decision expected mid-2026 | ~14.7% (Phase 3) |
| Retatrutide | Triple GIP/GLP-1/glucagon agonist | Phase 3 (7 readouts in 2026) | Up to 28.7% |
| Tirzepatide new indications | Dual GIP/GLP-1 agonist | Various Phase 3 | N/A |
Novo's strategy is molecular diversity — CagriSema adds amylin to semaglutide; amycretin combines GLP-1 and amylin activity in a single molecule. Both aim to match or beat tirzepatide's efficacy while leveraging Novo's semaglutide manufacturing and clinical expertise.
Lilly's strategy is escalation — retatrutide adds a third receptor target (glucagon) to the GIP/GLP-1 dual agonism of tirzepatide. With 28.7% weight loss, retatrutide could be the most effective obesity drug ever tested. Orforglipron, meanwhile, addresses the oral market with a small molecule that is easier to manufacture than peptide-based pills.
If retatrutide succeeds in Phase 3 and gains approval (estimated 2027-2028), Lilly will have the strongest obesity drug on the market. If orforglipron gains approval by mid-2026, Lilly will have both the best injectable and a competitive oral product. Novo needs CagriSema and amycretin to deliver — and to deliver on time.
Strategy Differences: Two Roads to the Same Market
Beyond individual products, the two companies have distinct strategic philosophies.
Novo Nordisk has always been a metabolic disease company. Over 80% of its revenue comes from diabetes and obesity. It has built the world's largest peptide manufacturing base, established deep relationships with endocrinologists and primary care providers, and invested heavily in patient support programs. Its approach is depth over breadth — own the metabolic space completely.
Eli Lilly is a diversified pharmaceutical company. GLP-1 drugs now represent over 60% of its quarterly revenue, but Lilly also has major franchises in oncology (Verzenio), Alzheimer's disease (Kisunla/donanemab), and immunology. This diversification means Lilly can absorb GLP-1 setbacks without existential risk — a luxury Novo does not have.
Lilly has also been more aggressive on manufacturing investment: over $18 billion committed since 2020, including facility acquisitions, greenfield construction, and expansion across the U.S. and Europe. Novo has invested heavily as well (including the $4 billion Clayton, NC expansion), but Lilly's manufacturing scale-up began earlier and has been more geographically diversified.
Manufacturing and Supply Chain
Both companies were hit by GLP-1 supply shortages in 2023-2024 that left patients unable to fill prescriptions for months. The experience forced both to rethink manufacturing strategy.
Novo Nordisk now has a $4 billion expansion underway at its North Carolina manufacturing hub, where the oral Wegovy pill is produced. The company expects capital expenditure of roughly DKK 55 billion (~$8 billion) in 2026 — a massive commitment to scaling production.
Eli Lilly has committed more than $18 billion since 2020 to build, expand, and acquire manufacturing facilities. This includes the purchase of Nexus Pharmaceuticals' plant, expansion of its Concord, NC facility, and new construction in Ireland for synthetic peptide manufacturing.
The CDMO (contract development and manufacturing organization) sector has also mobilized. CordenPharma pledged EUR 900 million for peptide production expansion. Simtra BioPharma launched a dedicated GLP-1 fill-and-finish facility in Indiana. Global peptide CDMO capacity is expanding at a 20% annual rate.
The Pricing Battle
Pricing is the wild card in this war.
Both companies entered agreements with the U.S. government in November 2025 to lower GLP-1 prices for Medicare recipients. Novo slashed list prices by up to 70%. Lilly introduced Zepbound vials at substantially lower prices than autoinjector pens.
Current cash-pay pricing:
| Product | Monthly Cost |
|---|---|
| Ozempic | ~$350 |
| Wegovy injectable | ~$350 |
| Wegovy pill (starter dose) | $149 |
| Zepbound | ~$346 |
For Novo, the pricing cuts are a double-edged sword. Lower prices expand the addressable market but directly compress revenue — the primary reason behind the negative 2026 guidance. For Lilly, Zepbound vials (roughly one-third of prescriptions) offer a lower-cost entry point that drives volume without cannibalizing premium autoinjector sales.
The Oral GLP-1 Showdown
The next battleground is pills. Novo has a first-mover advantage with oral Wegovy (launched January 5, 2026), but Lilly may have a structural advantage with orforglipron.
Oral Wegovy (semaglutide 25 mg pill):
- First oral GLP-1 approved for weight loss
- ~17% weight loss in OASIS 4 (on-treatment)
- Must be taken on an empty stomach with water; no food/drink for 30 minutes
- Hit 50,000 weekly prescriptions within three weeks of launch
- Priced at $149-$299/month depending on dose
Orforglipron (Lilly's oral candidate):
- Non-peptide small molecule GLP-1 agonist
- ~14.7% weight loss in Phase 3 ATTAIN-1
- Easier and cheaper to manufacture than peptide-based pills
- FDA decision expected mid-2026
- Expected pricing starts at $149/month under the Trump agreement
The manufacturing difference matters. Oral semaglutide is a peptide — it is complex and expensive to produce, requires an absorption enhancer (SNAC) to survive the stomach, and has bioavailability challenges. Orforglipron is a small molecule, which means simpler chemistry, lower production costs, and potentially greater scalability.
Analysts at Truist Securities estimate that orforglipron could contribute to $101 billion in combined peak sales when paired with Mounjaro and Zepbound. If that projection is even half right, oral GLP-1s will reshape the competitive map.
Investment Thesis: Which Stock Wins?
PeptideJournal.org does not provide financial advice. This section summarizes publicly available analyst opinions for educational context.
The bull case for Eli Lilly:
- 25% revenue growth guidance for 2026, with potential to reach $94 billion by 2027
- Superior clinical data (tirzepatide beats semaglutide on weight loss and glycemic control)
- Retatrutide could be the most effective obesity drug ever if Phase 3 confirms Phase 2 data
- Orforglipron approval would give Lilly a small-molecule oral advantage
- Diversified portfolio (Alzheimer's, oncology) reduces single-franchise risk
The bull case for Novo Nordisk:
- Trades at a TTM P/E of roughly 13 — substantially cheaper than Lilly
- Analyst expectations have already collapsed (2026 revenue consensus dropped 23%), meaning the bar for positive surprises is low
- CagriSema and amycretin could match or exceed tirzepatide's efficacy
- Oral Wegovy is first to market and ramping quickly
- The total addressable obesity market is large enough for multiple winners
- 62% global GLP-1 volume market share
The bear case for both:
- Government pricing pressure will compress margins across the class
- Insurance coverage pullbacks could slow volume growth
- Generic semaglutide (launching internationally in 2026) will erode Novo's global pricing
- Safety signals — though none have materialized at scale — remain a theoretical risk for the entire class
FAQ
Who is winning the GLP-1 war, Novo Nordisk or Eli Lilly?
By most financial and market share metrics, Eli Lilly is winning as of early 2026. Lilly holds over 60% of the U.S. incretin market, posted 45% revenue growth in 2025, and guided for $80-83 billion in 2026 revenue. Novo Nordisk's sales are projected to decline 5-13% in 2026.
Why is tirzepatide more effective than semaglutide?
Tirzepatide acts on two hormonal pathways — GIP and GLP-1 receptors — while semaglutide targets only GLP-1. The dual mechanism produces greater insulin secretion, better glucose control, and more weight loss. In the SURMOUNT trials, tirzepatide achieved ~22.5% weight loss versus ~15% for semaglutide in the STEP trials.
Can Novo Nordisk catch up?
Yes, but it requires its pipeline to deliver. CagriSema showed 22.7% weight loss in Phase 3, matching tirzepatide. Amycretin hit 22% in Phase 2. If both gain approval on schedule, Novo would have competitive products by 2027-2030. The question is whether market share lost during 2025-2027 can be recovered.
What is retatrutide and why does it matter?
Retatrutide is Eli Lilly's triple agonist that targets GIP, GLP-1, and glucagon receptors simultaneously. It achieved up to 28.7% weight loss in Phase 3 — the highest ever reported for an anti-obesity drug. If it gains approval (estimated 2027-2028), it could redefine what is achievable with pharmacological weight loss.
Is this a winner-take-all market?
No. The obesity market is projected to reach $100 billion by 2030, and the total addressable population is massive — over 40% of U.S. adults are classified as obese. There is room for multiple products, especially as oral formulations expand the patient pool. But market share concentration matters, and Lilly's current trajectory suggests it will capture a disproportionate share of that growth.
How do the companies compare on safety?
Both semaglutide and tirzepatide have similar side effect profiles, dominated by gastrointestinal symptoms (nausea, vomiting, diarrhea). These are generally mild and decrease over time with dose titration. Neither drug has shown significant safety signals at the population level, though long-term monitoring continues.
The Bottom Line
The Novo Nordisk vs. Eli Lilly rivalry is the defining pharmaceutical competition of the decade. What started as Novo's market to lose has become Lilly's to win.
Lilly's advantages are concrete: better clinical data, faster-growing market share, a more diversified company, and a pipeline headlined by the potentially game-changing retatrutide. Novo's advantages are real but more contingent: a cheaper stock price, first-mover status on oral GLP-1s, and a pipeline (CagriSema, amycretin) that could narrow the efficacy gap if everything goes right.
The companies reported their 2025 results within 24 hours of each other in February 2026. Lilly guided above expectations. Novo guided below. Lilly's stock climbed 7%. Novo's fell 15%.
That single day captured the current state of the war. But this is a multi-decade contest over a market that could exceed $150 billion. Novo is down, not out. Its scientific pedigree, global manufacturing base, and 100-year history of metabolic disease leadership make it a formidable competitor even in a down cycle. The question is whether it can execute fast enough on CagriSema and amycretin to prevent the market share gap from becoming permanent.
For patients, the war is unambiguously good news. More competition means lower prices, more options, and better drugs. The biggest winners in the Novo vs. Lilly battle will not be shareholders of either company. They will be the hundreds of millions of people worldwide living with obesity and type 2 diabetes who now have access to transformative treatments that did not exist five years ago.
References
- CNBC. "Eli Lilly's GLP-1 Growth Is Only Getting Started as Novo Nordisk Braces for a Decline in 2026." cnbc.com, February 2026.
- The Motley Fool. "Eli Lilly vs Novo Nordisk: Which Company Will Dominate the Weight Loss Drug Market in 2026?" fool.com, January 2026.
- 24/7 Wall St. "Eli Lilly Is Dominating the GLP-1 Wars as Novo Nordisk Sales Tank." 247wallst.com, February 2026.
- Eli Lilly. "Lilly Reports Fourth-Quarter 2025 Financial Results." investor.lilly.com, February 2026.
- Novo Nordisk. "Investor Presentation Full Year 2025." novonordisk.com, February 2026.
- BioSpace. "Lilly's Path to $94B in Revenue Rests on Oral Obesity Market and Other 2026 Milestones." biospace.com, 2026.
- Seeking Alpha. "Eli Lilly Soars, Novo Nordisk Plummets on GLP/Obesity Updates." seekingalpha.com, 2026.
- The Motley Fool. "Eli Lilly vs Novo Nordisk: The 1 Figure Investors Shouldn't Ignore." fool.com, February 2026.
- Novo Nordisk. "Our Heritage." novonordisk.com.
- Eli Lilly. "History | Milestones of Caring & Discovery." lilly.com.
- pharmaphorum. "A History of... Novo Nordisk." pharmaphorum.com.
- pharmaphorum. "A History of... Eli Lilly & Co." pharmaphorum.com.