Semaglutide and tirzepatide represent two generations of incretin-based therapy. Semaglutide is a GLP-1 receptor agonist; tirzepatide is a dual GIP/GLP-1 receptor agonist. Both achieve substantial HbA1c reduction and weight loss, but differ in acquisition cost, dosing frequency, and pharmacoeconomic profile. This analysis compares their cost-effectiveness across clinical and economic dimensions.
| Parameter | Semaglutide (Ozempic) | Semaglutide (Wegovy) | Tirzepatide (Mounjaro) | Tirzepatide (Zepbound) |
|---|
| Monthly cost | $935–969 | $1,349 | $1,023–1,069 | $1,059 |
| Annual cost | $11,220–11,628 | $16,188 | $12,276–12,828 | $12,708 |
| Dose range | 0.25–2 mg/week | 2.4 mg/week | 2.5–15 mg/week | 2.5–15 mg/week |
| Pen device | Single-dose pen | Single-dose pen | Single-dose pen | Single-dose pen |
| Injection frequency | Once weekly | Once weekly | Once weekly | Once weekly |
| Country | Semaglutide (monthly) | Tirzepatide (monthly) | Difference |
|---|
| United States | $935–1,349 | $1,023–1,059 | Variable |
| United Kingdom | £75–90 | £80–95 | ~5–10% more |
| Germany | €280–350 | €300–370 | ~5–10% more |
| Canada | CAD $300–400 | CAD $320–420 | ~5–10% more |
| Australia | AUD $130–180 | AUD $140–190 | ~5–10% more |
| Metric | Semaglutide | Tirzepatide | Interpretation |
|---|
| ICER (per QALY gained) | $15,000–25,000 | $18,000–30,000 | Both below $50K threshold |
| QALY gain (vs placebo) | 0.8–1.2 | 1.0–1.5 | Tirzepatide slightly higher |
| NNT (HbA1c <7%) | 3–4 | 2–3 | Tirzepatide more efficacious |
| NNT (weight loss ≥10%) | 4–5 | 2–3 | Tirzepatide more efficacious |
| Annual drug cost | $11,220–16,188 | $12,276–12,828 | Semaglutide (Wegovy) higher |
| Threshold | Semaglutide | Tirzepatide |
|---|
| $50,000/QALY (US) | Cost-effective | Cost-effective |
| $100,000/QALY (US) | Highly cost-effective | Highly cost-effective |
| £20,000/QALY (UK/NICE) | Cost-effective | Cost-effective |
| €50,000/QALY (EU) | Cost-effective | Cost-effective |
| Parameter | Semaglutide (Ozempic) | Tirzepatide (Mounjaro) |
|---|
| HbA1c reduction | −1.0 to −1.8% | −1.5 to −2.4% |
| Weight loss | 3–5 kg | 5–9 kg |
| MACE reduction | 26% (SUSTAIN-6) | Pending (SURPASS-CVOT) |
| Annual cost | $11,220–11,628 | $12,276–12,828 |
| QALY gain | 0.8–1.2 | 1.0–1.5 |
| ICER | $15,000–20,000 | $18,000–25,000 |
| Parameter | Semaglutide (Wegovy) | Tirzepatide (Zepbound) |
|---|
| Weight loss | 12–15% | 15–22% |
| Annual cost | $16,188 | $12,708 |
| QALY gain | 1.0–1.5 | 1.2–1.8 |
| ICER | $20,000–30,000 | $18,000–25,000 |
| CV benefit | SELECT trial (20% MACE reduction) | Pending |
| Scenario | Annual Budget Impact | Per-Member Per-Month |
|---|
| Semaglutide (5% uptake) | $675,000 | $5.63 |
| Tirzepatide (5% uptake) | $641,400 | $5.35 |
| Mixed formulary (3% Sema, 2% Tirz) | $593,880 | $4.95 |
| Cost Category | Semaglutide | Tirzepatide |
|---|
| Drug cost | $11,220–16,188/yr | $12,276–12,828/yr |
| Lost productivity savings | $2,000–4,000/yr | $2,500–5,000/yr |
| Complication avoidance | $3,000–8,000/yr | $4,000–10,000/yr |
| Net societal cost | −8,000/yr | −12,000/yr |
| Criterion | Semaglutide | Tirzepatide |
|---|
| HbA1c requirement | ≥7.0% (diabetes) | ≥7.0% (diabetes) |
| BMI requirement | ≥30 or ≥27 + comorbidity (obesity) | ≥30 or ≥27 + comorbidity (obesity) |
| Step therapy | Often 1–2 oral agents first | Often 1–2 oral agents first |
| Duration of coverage | 6–12 months, then reassess | 6–12 months, then reassess |
| Agent | Biosimilar Expected | Price Impact |
|---|
| Semaglutide | 2031 (patent expiry) | 30–50% reduction |
| Tirzepatide | 2036+ (patent expiry) | Limited near-term impact |
| Metric | Semaglutide | Tirzepatide |
|---|
| 6-month persistence | 50–60% | 55–65% |
| Injection adherence | 80–90% | 85–95% |
| Dose escalation success | 70–80% | 75–85% |
| Discontinuation (side effects) | 10–15% | 8–12% |
| Outcome | Semaglutide | Tirzepatide |
|---|
| Cost per 1% HbA1c reduction | $6,000–8,000 | $5,000–6,000 |
| Cost per 5% weight loss | $10,000–15,000 | $7,000–10,000 |
| Cost per QALY gained | $15,000–25,000 | $18,000–30,000 |
Both semaglutide and tirzepatide are cost-effective at standard willingness-to-pay thresholds. Tirzepatide offers greater HbA1c and weight reduction at a comparable annual cost, resulting in a lower cost per unit of clinical benefit. Semaglutide has longer cardiovascular outcome data (SUSTAIN-6, SELECT), which may influence payer preference. For obesity, semaglutide (Wegovy) has a higher list price than tirzepatide (Zepbound), but real-world cost depends on insurance coverage, copay assistance, and patient assistance programs. The optimal choice depends on clinical profile, payer formulary, and patient preference.
