Mounjaro vs Zepbound: label, access, and payer coverage compared

Mounjaro (tirzepatide) and Zepbound (tirzepatide) are the same molecule manufactured by Eli Lilly, approved for different indications and covered under different payer pathways. Mounjaro carries the type 2 diabetes indication. Zepbound carries the chronic weight management and obstructive sleep apnea indications. Because they share the same active ingredient and dosing, which product a patient receives often depends on their primary diagnosis, their plan's formulary, and whether the plan covers anti-obesity medications at all.

This comparison is for access teams, prior authorization coordinators, and prescribers who need to navigate the practical differences between the two products.

Short answer

FDA-approved indications

Mounjaro indications

1. Glycemic control in adults and pediatric patients aged 10 years and older with type 2 diabetes as an adjunct to diet and exercise (SURPASS program, approved May 2022; pediatric expansion approved December 2025).

Mounjaro is not FDA-approved for weight management, cardiovascular risk reduction, or obstructive sleep apnea.

Zepbound indications

1. Chronic weight management in adults with obesity (BMI ≥30) or overweight (BMI ≥27) with at least one weight-related comorbid condition (e.g., hypertension, dyslipidemia, T2D, OSA, or cardiovascular disease), used with reduced-calorie diet and increased physical activity (SURMOUNT program, approved November 2023).
2. Treatment of moderate-to-severe obstructive sleep apnea in adults with obesity, used with reduced-calorie diet and increased physical activity (SURMOUNT-OSA, approved December 2024).

Zepbound is not FDA-approved for type 2 diabetes or cardiovascular risk reduction.

Clinical evidence comparison

Mechanism

Both products contain tirzepatide, a dual GIP (glucose-dependent insulinotropic polypeptide) and GLP-1 (glucagon-like peptide-1) receptor agonist. The dual mechanism enhances insulin sensitivity, suppresses glucagon, slows gastric emptying, and reduces appetite beyond what GLP-1 activation alone achieves.

Key trials

SURPASS program (Mounjaro, T2D): Multiple Phase 3 trials demonstrated superior A1C reduction and weight reduction with tirzepatide versus comparators including semaglutide 1 mg (SURPASS-2), insulin degludec (SURPASS-3), and insulin glargine (SURPASS-5).

SURMOUNT program (Zepbound, obesity): SURMOUNT-1 showed mean body weight reduction of up to 22.5% at 72 weeks in adults with obesity or overweight without diabetes. SURMOUNT-2 evaluated tirzepatide in adults with T2D and obesity, demonstrating up to 15.7% weight reduction.

SURMOUNT-OSA (Zepbound, OSA): Two randomized, double-blind, placebo-controlled Phase 3 studies enrolled 469 adults with moderate-to-severe OSA and obesity. Zepbound 10 mg and 15 mg reduced apnea-hypopnea index (AHI) events by approximately 25–29 events per hour versus 5–6 events for placebo at 52 weeks. Nearly half of Zepbound-treated participants no longer had symptoms associated with OSA at one year.

Cardiovascular and kidney outcomes

Neither Mounjaro nor Zepbound carries an FDA-approved indication for cardiovascular or kidney risk reduction. This differentiates tirzepatide from semaglutide, where Ozempic carries MACE reduction and CKD progression indications, and Wegovy carries a MACE reduction indication.

Pediatric indication

Mounjaro received FDA approval for use in pediatric patients aged 10 years and older with type 2 diabetes in December 2025. Zepbound is not approved for use in patients under 18 years of age.

Coverage comparison by payer

Commercial insurance

For plans that do not cover anti-obesity medications, Zepbound may be excluded entirely regardless of clinical need. Patients in these plans would need to use the manufacturer's self-pay program.

Key commercial payer developments in 2025–2026:

• Blue Cross Blue Shield of Massachusetts announced that effective January 1, 2026 (on plan renewal), Wegovy, Saxenda, and Zepbound will be excluded from coverage. Mounjaro, Ozempic, and Trulicity coverage for T2D is unchanged.
• CVS Caremark removed Zepbound from its formularies in 2025.
• UnitedHealthcare covers Zepbound on plans that have elected weight-loss medication coverage, with prior authorization requiring BMI ≥40 or BMI ≥30 with specific comorbidities.

Medicare Part D

Medicare GLP-1 Bridge: Starting July 1, 2026, CMS will make the KwikPen formulation of Zepbound available to eligible Medicare beneficiaries at no more than $50 per month through the Medicare GLP-1 Bridge program. The single-dose pen and single-dose vial formulations are not included. Beneficiaries prescribed Zepbound for OSA (which is coverable under standard Part D) would not use the Bridge; the Bridge is for weight-loss-only use.

Mounjaro is widely covered under Part D for T2D. More than 90% of commercial and Part D plans cover Mounjaro for T2D per Eli Lilly.

Medicaid

Medicaid coverage for both products varies significantly by state:

• Mounjaro: Many state Medicaid programs cover Mounjaro for adults with T2D with prior authorization and documentation of prior therapy. Pennsylvania Medicaid, for example, requires trial and failure of maximum FDA-approved doses of Ozempic and Wegovy before approving Mounjaro.
• Zepbound: Coverage is more restrictive. Some states (e.g., South Carolina) deny Zepbound for weight loss and OSA. Others (e.g., North Carolina) cover Zepbound for OSA with stricter criteria. New Hampshire ended coverage for weight-loss-only use in January 2026 but maintained the OSA pathway.

Prior authorization criteria

Mounjaro PA (typical commercial)

1. Documented diagnosis of type 2 diabetes.
2. Trial and failure, contraindication, or intolerance to metformin (unless contraindicated).
3. Some plans require trial of a GLP-1 receptor agonist first (e.g., Ozempic, Trulicity).
4. A1C documentation within the past 3–6 months.
5. Prescribed by or in consultation with an endocrinologist or relevant specialist.

Zepbound PA for weight management (typical commercial)

1. BMI ≥30, or BMI ≥27 with at least one weight-related comorbidity (hypertension, dyslipidemia, T2D, OSA, cardiovascular disease).
2. Documented participation in a structured lifestyle modification program.
3. Some plans require trial and failure of other weight-loss medications (e.g., Contrave, Qsymia, Saxenda, Wegovy).
4. Prior authorization renewal every 5–6 months typically requires documentation of ≥5% body weight loss.
5. Pennsylvania Medicaid requires trial and failure of maximum doses of Ozempic, Wegovy, and Mounjaro before approving Zepbound.

Zepbound PA for OSA (typical commercial and Part D)

1. Age 18 or older.
2. BMI ≥30.
3. Documented moderate-to-severe OSA by sleep study (AHI or REI ≥15 events per hour).
4. Trial and continued use (or documented inability to use) positive airway pressure therapy.
5. Lifestyle modification counseling documented.
6. Prescribed by or in consultation with a sleep specialist.
7. Not a candidate for or planning sleep apnea surgery.
8. Reauthorization at 6 months requires continued clinical benefit.

Manufacturer savings programs

Mounjaro Savings Card

• Commercially insured patients with T2D may pay as little as $0 per month (terms vary; maximum annual benefit applies).
• Patients without insurance coverage are not eligible for the commercial savings card.

Zepbound Self Pay Journey Program

• Available for patients paying cash without insurance coverage for Zepbound.
• Tiered pricing: $299/month for 2.5 mg, $399/month for 5 mg, and $449/month for 7.5 mg, 10 mg, 12.5 mg, and 15 mg (single-dose vial or KwikPen).
• This is the primary access pathway for patients whose plans exclude weight-loss drugs.

Zepbound Savings Card

• Commercially insured patients whose plans cover Zepbound may be eligible for a copay assistance program.
• Patients on government-funded insurance (Medicare, Medicaid, TRICARE) are not eligible.

Macro coverage trend

Between 2025 and 2026, an estimated 12 million people lost insurance coverage for Zepbound and 12 million lost coverage for Wegovy, as employers and insurers tightened GLP-1 anti-obesity drug benefits. This trend disproportionately affects Zepbound, which depends on weight-loss and OSA coverage pathways that are being reassessed by many plan sponsors. Mounjaro has been relatively insulated because its T2D indication is standard in medical benefit design.

For Medicaid, only 13 states explicitly cover Zepbound for weight loss as of January 2026. Coverage for Zepbound prescribed for OSA is available in more states but still requires prior authorization with sleep study documentation and BMI thresholds. Mounjaro for diabetes is commonly covered across all state Medicaid programs with varying PA requirements.

What to monitor

1. Medicare GLP-1 Bridge rollout (July 2026): CMS will begin offering the Zepbound KwikPen to eligible beneficiaries. Adoption and formulary integration will affect Part D coverage patterns.
2. Employer GLP-1 coverage decisions: Several large employers and insurers are reassessing weight-loss drug coverage for 2026 and 2027. Monitor formulary exclusion announcements.
3. Tirzepatide cardiovascular outcomes (SURPASS-OUTCOMES): A cardiovascular outcomes trial for Mounjaro is ongoing. If positive, it could add a MACE reduction indication and shift payer preference.
4. Oral tirzepatide: Eli Lilly is developing an oral formulation. If approved, it could change the access and coverage landscape for both Mounjaro and Zepbound.
5. State Medicaid OSA coverage: As more states develop Zepbound OSA coverage criteria, PA pathways will standardize. Monitor state-specific Medicaid bulletins.

Sources

• FDA. Zepbound (tirzepatide) prescribing information. Revised April 2025. https://www.accessdata.fda.gov/drugsatfda_docs/label/2026/215866s041lbl.pdf
• FDA. Mounjaro (tirzepatide) prescribing information. Revised January 2026. https://www.accessdata.fda.gov/drugsatfda_docs/label/2026/215866s041lbl.pdf (Reference ID: 5723960)
• FDA. FDA Approves First Medication for Obstructive Sleep Apnea. Press release. December 20, 2024. https://www.fda.gov/news-events/press-announcements/fda-approves-first-medication-obstructive-sleep-apnea
• Malhotra A, Grunstein R, Fietze I, et al. Tirzepatide for the Treatment of Obstructive Sleep Apnea and Obesity. N Engl J Med. 2024;391(13):1193–1205.
• CMS. Medicare GLP-1 Bridge. Updated April 6, 2026. https://www.cms.gov/medicare/coverage/prescription-drug-coverage/medicare-glp-1-bridge
• Eli Lilly and Company. Open letter regarding the use of Mounjaro and Zepbound. Accessed May 2026.
• Blue Cross Blue Shield of Massachusetts. GLP-1 Coverage FAQ. January 2026.
• UnitedHealthcare. Prior Authorization/Notification — Plans with Weight Loss/Appetite Suppression Medication Coverage. Effective May 1, 2026.
• Pennsylvania Department of Human Services. Medical Assistance Bulletin — Prior Authorization of Pharmaceutical Services. January 1, 2026.
• AARP. Does Medicare Cover Ozempic, Other Weight Loss Drugs? Updated 2026.
• NPR. Restrictions on obesity drug coverage force patients to pivot. April 2026.
• Noom. Does Insurance Cover Tirzepatide? Check Coverage in 2026. Accessed May 2026.
• WeightWatchers. Zepbound vs Mounjaro: Difference Between Mounjaro & Zepbound. Accessed May 2026.
• Drugs.com. Zepbound vs Mounjaro: Comparison Guide. Updated February 2026.