Eli Lilly's GLP-1 Lineup: Mounjaro, Zepbound, Foundayo and Retatrutide (2026)

Eli Lilly's GLP-1 program is arguably the most advanced in the industry. Between Mounjaro and Zepbound (both tirzepatide), the company holds the lead on average weight loss in the approved class. The 2026 addition of Foundayo (orforglipron) is the first oral small-molecule GLP-1. And retatrutide, the triple agonist in Phase 3, may extend Lilly's lead further when it crosses the FDA line in 2027–2028.

This is the rundown of Lilly's GLP-1 portfolio in 2026.

Mounjaro (tirzepatide for type 2 diabetes)

• FDA-approved: 2022
• Indication: Type 2 diabetes
• Class: Dual GLP-1 / GIP agonist
• Form: Weekly subcutaneous injection
• Doses: 2.5 / 5 / 7.5 / 10 / 12.5 / 15 mg
• Trial program: SURPASS
• A1c reduction: ~2.0 percentage points at top dose
• Weight loss (T2D): Up to 15-20% in some SURPASS trial cohorts
• List price: ~$1,069/month

See Mounjaro: is it a GLP-1? for the full drug guide.

Zepbound (tirzepatide for weight management + OSA)

• FDA-approved: 2023 (weight management); 2024 (obstructive sleep apnea in adults with obesity)
• Indication: Chronic weight management; OSA
• Class: Dual GLP-1 / GIP agonist
• Form: Weekly injection (pens, KwikPen, LillyDirect vials)
• Doses: 2.5 / 5 / 7.5 / 10 / 12.5 / 15 mg
• Trial program: SURMOUNT-1, SURMOUNT-OSA
• Average weight loss: ~21% body weight at 72 weeks (SURMOUNT-1)
• List price: ~$1,299/month (pens); $349-$499/month via LillyDirect vials

Zepbound is the best-selling weight-loss drug by trial efficacy among FDA-approved options.

Foundayo (orforglipron — oral small molecule)

• FDA-approved: 2026 (under the FDA's National Priority Voucher program — an expedited review)
• Indication: Chronic weight management (with separate T2D filing)
• Class: Single GLP-1 receptor agonist (small molecule, not peptide)
• Form: Once-daily oral tablet
• Doses: 0.8 / 2.4 / 4.8 / 7.2 / 10.4 / 13.8 / 17.2 mg
• Trial program: ATTAIN, ACHIEVE
• Average weight loss: ~12% body weight at top dose (~27 lb mean loss)
• List price: From $149/month (LillyDirect cash); ~$25/month with commercial coverage + Lilly discount card; ~$50/month for Medicare Part D enrollees starting July 2026

Foundayo's distinguishing features:

• Take any time of day — no fasting window like oral Wegovy
• No food restrictions — works with or without meals
• Small-molecule pharmacology — easier to manufacture and distribute than peptide drugs
• Maintenance use after injection success — Lilly published Phase 3 data showing Foundayo helps patients maintain weight loss after stopping injectable Wegovy or Zepbound. Switching from Wegovy preserved ~95% of weight loss; switching from Zepbound preserved ~80%.

This is meaningful: an oral maintenance option could become a major practical solution for the chronic-condition framing of GLP-1 treatment.

Retatrutide (Phase 3, triple agonist)

• Status: Phase 3 (TRIUMPH program); NDA expected late 2026; approval projected 2027–2028
• Class: Triple GLP-1 / GIP / glucagon receptor agonist
• Form: Weekly subcutaneous injection
• Phase 2 weight loss: ~24% body weight at 48 weeks (12 mg dose, NEJM 2023)
• Distinguishing feature: Glucagon receptor activation raises energy expenditure on top of appetite suppression

See our Retatrutide pillar and Retatrutide vs GLP-1 for the deep dive.

Lilly's GLP-1 access programs

Lilly has built one of the most aggressive direct-to-consumer manufacturer programs:

• LillyDirect — direct-from-Lilly pharmacy; cheaper cash-pay options for Zepbound vials and Foundayo
• Zepbound Savings Card — $25 copay for commercially insured patients
• Mounjaro Savings Card — $25 copay for commercially insured T2D patients

LillyDirect was a meaningful market shift — it took Eli Lilly out of the standard "PBM markup" pricing chain for cash-pay patients.

Lilly's competitive position

Each Lilly drug is class-leading in its segment:

• Mounjaro: Top weight loss in T2D trials
• Zepbound: Top weight loss in weight-management trials
• Foundayo: First oral small-molecule GLP-1; class-leading convenience
• Retatrutide: Highest Phase 2 weight-loss numbers of any metabolic drug

This is part of a broader pattern: Lilly has invested heavily in metabolic therapeutics and has the deepest near-term pipeline.

The 2026 Lilly portfolio at a glance

What's not in Lilly's GLP-1 portfolio

• Single-receptor weekly injection competitor to Wegovy — Lilly doesn't have a direct single-agonist semaglutide competitor; their position is the higher-efficacy dual agonist instead
• Oral semaglutide-equivalent — Novo Nordisk holds Rybelsus and oral Wegovy; Lilly's oral entry is the small-molecule orforglipron
• Liraglutide-equivalent — Lilly doesn't compete in the daily- injection space; Novo holds that with Saxenda

FAQ

Who makes Mounjaro and Zepbound? Eli Lilly. Both are tirzepatide; Mounjaro is the diabetes brand, Zepbound is the weight-management brand.

Is Foundayo from Eli Lilly? Yes — Eli Lilly's first oral GLP-1 receptor agonist, approved in 2026.

Is retatrutide from Eli Lilly? Yes — Lilly's triple-agonist program, currently in Phase 3 trials.

What's the cheapest Eli Lilly GLP-1 in 2026? Foundayo at $149/month cash via LillyDirect, or Zepbound vials at $349-$499/month.

Who is Eli Lilly's main competitor in the GLP-1 space? Novo Nordisk, makers of Ozempic, Wegovy, Rybelsus, Saxenda, and Victoza. See Novo Nordisk GLP-1.

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This article is for educational purposes only and is not medical advice. Discuss treatment options with a qualified healthcare professional.