This page presents the same data as our consumer pages but in a denser, tabular format suitable for clinical reference. All values are from published Phase 3 trial results. Weight loss percentages are mean total body weight change from baseline in the drug arm, not placebo-subtracted unless otherwise noted. Source links are provided for every trial.
Consumer-friendly version with plain English summaries →Approved medications — summary
| Drug | Form | Max weight loss | Key trial | Cost (list) |
|---|---|---|---|---|
| Zepbound & Mounjaro Tirzepatide | Once-weekly injection | 20.9% | SURMOUNT-1 | Self-pay vials via LillyDirect from $299/month (2.5 mg) to $449/month (7.5 mg and above); ~$1,086/month list price; $25/month copay card for eligible commercial insurance |
| Wegovy & Ozempic Semaglutide | Injection: once-weekly · Pill: once-daily | 14.9% | STEP 1 | Pill: $149–$299/month self-pay by dose (~$25 with insurance). Injection: $349–$399/month self-pay via NovoCare Pharmacy (list price ~$1,349/month; ~$25 with commercial insurance). |
| Saxenda Liraglutide | Daily injection | 8% | SCALE Obesity and Prediabetes | Brand (Saxenda): ~$1,000–$1,349/month. Generic liraglutide (Teva, approved August 2025): typically $135–$200 less than brand. Check pharmacy pricing. |
| Qsymia Phentermine / Topiramate ER | Daily oral capsule — no injection | 9.8% | CONQUER | ~$30–$80/month generic; ~$200–$400/month brand (Qsymia) |
| Contrave Naltrexone / Bupropion ER | Twice-daily oral tablet — no injection | 9.3% | COR-I | ~$100–$400/month (brand). Generic available in some markets. |
| Xenical & Alli Orlistat | Three capsules daily, taken with each fat-containing meal | 8.5% | XENDOS | Rx ~$200–$400/month (Xenical); OTC ~$40–$60/month (Alli 60mg) |
| Foundayo Orforglipron | Once-daily pill — no injection, no fasting, no food timing | 12.4% | ATTAIN-1 | $149/month self-pay (lowest dose), up to $349/month (highest dose) via LillyDirect. $25/month with commercial insurance savings card. Medicare Part D ~$50/month expected from July 2026. Available since April 6, 2026. |
Detailed trial data — approved drugs
Tirzepatide
| Trial | Phase | N | Duration | Comparator | Weight loss | ≥5% | ≥20% | Source |
|---|---|---|---|---|---|---|---|---|
| SURMOUNT-1 | Phase 3 | 2,539 | 72 weeks | Placebo | 20.9% at highest dose (15 mg) | 89% | 50% | New England Journal of Medicine, 2022 |
| SURMOUNT-3 | Phase 3 | — | 72 weeks | Placebo (after lifestyle lead-in) | ~26% total from original baseline (18.4% additional after lifestyle phase) | — | — | Nature Medicine, 2024 |
| SURMOUNT-4 | Phase 3 | — | 88 weeks total (36-week lead-in + 52-week randomised phase) | Placebo (withdrawal study) | 25.3% total over 88 weeks; 14% regain after stopping | — | — | JAMA, 2024 |
| SURMOUNT-5 | Phase 3 | — | 72 weeks | Semaglutide 2.4 mg (head-to-head) | Tirzepatide was superior to semaglutide on weight loss and waist circumference | — | — | New England Journal of Medicine, 2025 |
| SURMOUNT-1 Body Composition Substudy | Phase 3 substudy | 160 | 72 weeks | Placebo | 75% fat mass / 25% lean mass composition of weight lost | — | — | Obesity, 2024 |
Semaglutide (injection)
| Trial | Phase | N | Duration | Comparator | Weight loss | ≥5% | ≥20% | Source |
|---|---|---|---|---|---|---|---|---|
| STEP 1 | Phase 3 | 1,961 | 68 weeks | Placebo | 14.9% average weight loss | 86% | — | New England Journal of Medicine, 2021 |
| STEP 2 | Phase 3 | — | 68 weeks | Placebo | 9.6% average weight loss (lower in people with diabetes) | — | — | New England Journal of Medicine, 2021 |
| STEP 5 | Phase 3 | — | 104 weeks (2 years) | Placebo | 15.2% sustained at 2 years | — | — | Nature Medicine, 2022 |
| OASIS 4 | Phase 3 | 307 | 64 weeks | Placebo | 13.6% average (16.6% with full adherence) | 76% | 33% | New England Journal of Medicine, 2024 |
| SELECT | Phase 3 (cardiovascular outcomes) | 17,604 | ~40 months (median) | Placebo | 20% reduction in heart attacks, strokes, and cardiovascular death | — | — | New England Journal of Medicine, 2023 |
| ORION | Indirect Comparison | — | 64–72 weeks | Cross-trial indirect comparison | Oral semaglutide showed ~3.2 percentage points more weight loss than orforglipron | — | — | Presented at Obesity Medicine Association (OMA) 2026, 2026 |
Liraglutide
| Trial | Phase | N | Duration | Comparator | Weight loss | ≥5% | ≥20% | Source |
|---|---|---|---|---|---|---|---|---|
| SCALE Obesity and Prediabetes | Phase 3 | 3,731 | 56 weeks | Placebo | 8.0% average weight loss | 63% | — | New England Journal of Medicine, 2015 |
| SCALE Diabetes | Phase 3 | — | 56 weeks | Placebo | 6.0% in people with type 2 diabetes | — | — | JAMA, 2015 |
Phentermine / Topiramate
| Trial | Phase | N | Duration | Comparator | Weight loss | ≥5% | ≥20% | Source |
|---|---|---|---|---|---|---|---|---|
| CONQUER | Phase 3 | 2,487 | 56 weeks | Placebo | 9.8% at full dose (15/92 mg) | 70% | — | The Lancet, 2011 |
| SEQUEL | Phase 3 extension | — | 108 weeks total (2 years) | Placebo | Sustained weight loss with continued health improvements at 2 years | — | — | American Journal of Clinical Nutrition, 2012 |
Naltrexone / Bupropion
| Trial | Phase | N | Duration | Comparator | Weight loss | ≥5% | ≥20% | Source |
|---|---|---|---|---|---|---|---|---|
| COR-I | Phase 3 | 1,742 | 56 weeks | Placebo | 6.1% average weight loss | 48% | — | The Lancet, 2010 |
| COR-BMOD | Phase 3 | — | 56 weeks | Placebo + intensive behaviour therapy | 9.3% with drug + behaviour therapy (vs 5.1% placebo + therapy) | — | — | Obesity, 2011 |
Orlistat
| Trial | Phase | N | Duration | Comparator | Weight loss | ≥5% | ≥20% | Source |
|---|---|---|---|---|---|---|---|---|
| XENDOS | Phase 3 | 3,305 | 4 years (208 weeks) | Placebo + lifestyle intervention | 2.8 kg more weight loss than placebo at 4 years | — | — | Diabetes Care, 2004 |
| Sjostrom 1-year RCT | Phase 3 | 743 | 1 year (52 weeks) | Placebo | 8.5% average weight loss vs 5.4% placebo | — | — | International Journal of Obesity, 2000 |
Orforglipron
| Trial | Phase | N | Duration | Comparator | Weight loss | ≥5% | ≥20% | Source |
|---|---|---|---|---|---|---|---|---|
| ATTAIN-1 | Phase 3 | 3,127 | 72 weeks | Placebo | 12.4% at highest dose (36 mg trial capsule = 17.2 mg tablet) | — | — | New England Journal of Medicine, 2025 |
| ACHIEVE-3 | Phase 3 | 1,698 | 52 weeks | Oral semaglutide 14mg (diabetes dose, not 25mg obesity dose) | 9.2% orforglipron vs 5.3% oral semaglutide (diabetes dose) | — | — | The Lancet, 2026 |
Phentermine
| Trial | Phase | N | Duration | Comparator | Weight loss | ≥5% | ≥20% | Source |
|---|---|---|---|---|---|---|---|---|
| Kim 2006 (Seoul 12-week trial) | Randomised controlled trial | 68 | 12 weeks (after a 2-week placebo run-in) | Placebo | 6.7 kg lost on phentermine 37.5 mg once daily, significantly more than placebo | — | — | Yonsei Medical Journal, 2006 |
| Lewis 2019 (PORTAL health-record cohort) | Retrospective cohort study | 13,972 | Up to 3 years of follow-up, with weight measured at 6, 12 and 24 months | People who used phentermine for 3 months or less (on-label use) | 7.5% of body weight at 24 months in the 144 people who took phentermine continuously for more than a year, against 2.7% at 6 months in short-term users | — | — | Obesity, 2019 |
Setmelanotide
| Trial | Phase | N | Duration | Comparator | Weight loss | ≥5% | ≥20% | Source |
|---|---|---|---|---|---|---|---|---|
| POMC and LEPR phase 3 trials | Phase 3 | 21 | About 1 year | None (single-arm, open-label, with an 8-week blinded withdrawal period) | 80% (8 of 10) in the POMC/PCSK1 trial and 45% (5 of 11) in the leptin-receptor trial lost at least 10% of body weight at about 1 year | — | — | The Lancet Diabetes & Endocrinology, 2020 |
| Bardet-Biedl and Alstrom syndrome phase 3 trial | Phase 3 | 38 | 14-week placebo-controlled period followed by a 52-week open-label period | Placebo for the first 14 weeks, then open-label | 32.3% of patients aged 12 and over with Bardet-Biedl syndrome lost at least 10% of body weight at 52 weeks (p=0.0006) | — | — | The Lancet Diabetes & Endocrinology, 2022 |
| TRANSCEND | Phase 3 | 120 | 52 weeks after a dose-escalation period | Placebo (randomised 2:1) | BMI fell 16.5% at 52 weeks (least-squares mean), against a 3.3% rise on placebo (p<0.001) | — | — | New England Journal of Medicine, 2026 |
Plenity (Gelesis100)
| Trial | Phase | N | Duration | Comparator | Weight loss | ≥5% | ≥20% | Source |
|---|---|---|---|---|---|---|---|---|
| GLOW | Pivotal device trial | 436 | 24 weeks | Placebo (identical capsules filled with raw cane sugar) | 6.4% average body-weight loss vs 4.4% on placebo at 24 weeks (p=0.0007) | 59% | — | Obesity, 2019 |
Pipeline drugs — trial data
These drugs are not yet FDA-approved. Trial data is from published results as of June 2026. Timelines are estimates.
| Drug | Trial | Phase | N | Duration | Weight loss | Source |
|---|---|---|---|---|---|---|
| Retatrutide | Phase 2 RCT | Phase 2 | 338 | 48 weeks | 24.2% at highest dose (12 mg) — weight still dropping at 48 weeks | New England Journal of Medicine, 2023 |
| Orforglipron | ATTAIN-2 | Phase 3 | — | 72 weeks | 10.5% at highest dose (in people with type 2 diabetes) | The Lancet, 2025 |
| Orforglipron | ATTAIN-MAINTAIN | Phase 3 | — | 52 weeks | Maintained weight from prior injectable treatment (only 0.9 kg difference) | Eli Lilly press release, 2025 |
| CagriSema | REDEFINE 1 | Phase 3 | 3,417 | 68 weeks | 20.4% average (22.7% with full adherence) | New England Journal of Medicine, 2025 |
| CagriSema | REDEFINE 2 | Phase 3 | 1,206 | 68 weeks | 13.7% average (15.7% with full adherence) | New England Journal of Medicine, 2025 |
| Amycretin (injection) | Phase 1b/2a (subcutaneous) | Phase 1b/2a | — | 36 weeks | 22% at 20 mg weekly injection | Presented at EASD 2024, 2024 |
| Amycretin (oral pill) | Phase 1 (oral formulation) | Phase 1 | — | 12 weeks | 13.1% in just 12 weeks (oral pill) | EASD 2024 annual meeting, 2024 |
| MariTide | Phase 2 dose-finding study | Phase 2 | — | 52 weeks | Up to ~20% (non-diabetic); ~17% (with type 2 diabetes) | Nature Medicine, 2024 |
| Retatrutide | TRIUMPH-4 | Phase 3 | — | 68 weeks | 28.7% average weight loss at 12 mg — about 71 lbs on average | Eli Lilly press release, 2026 |
| Elecoglipron | VISTA (Phase 2b) | Phase 2b | 310 | 36 weeks | 10.5% at 26 weeks, rising to 11.8% at 36 weeks (75 mg, top dose) | The Lancet, 2026 |
| Elecoglipron | SOLSTICE (Phase 2b) | Phase 2b | 404 | 26 weeks | 7.7% weight loss and 1.9-point HbA1c reduction at 26 weeks (75 mg, top dose) | The Lancet, 2026 |
| Survodutide | SYNCHRONIZE-1 (Phase 3) | Phase 3 | 725 | 76 weeks | 16.6% at 76 weeks (6.0 mg weekly, efficacy estimand; 13.0% counting everyone who started) | The New England Journal of Medicine, 2026 |
| Survodutide | SYNCHRONIZE-MASLD (Phase 3) | Phase 3 | 218 | 48 weeks | 12.2% at 48 weeks (6.0 mg weekly) | Presented at the American Diabetes Association 2026 Scientific Sessions, 2026 |
GI side effect rates — approved GLP-1 drugs
From pivotal trial data. Rates are for the highest approved dose vs placebo.
| Side effect | Zepbound & Mounjaro | Wegovy & Ozempic | Saxenda | Qsymia | Contrave | Xenical & Alli | Foundayo |
|---|---|---|---|---|---|---|---|
| Nausea | 31% | 44% | 40% | — | 33% | — | 33% |
| Diarrhoea | 23% | 30% | 21% | — | — | — | 15% |
| Vomiting | 18% | 24% | 16% | — | 11% | — | 19% |
| Constipation | 12% | 24% | 19% | 17% | 19% | — | 18% |
About this reference
This page is designed as a quick clinical reference, not a comprehensive review. All data is sourced from published peer-reviewed trials and FDA prescribing information. Weight loss figures are mean values from the primary efficacy endpoints of each trial. Individual patient results vary. For prescribing decisions, consult the full prescribing information for each medication.
Plain Decisions is a consumer health information site. We are not a medical practice and do not provide clinical recommendations.
Reference notes
Unless otherwise noted, weight loss percentages shown are mean values from the primary efficacy endpoint of each pivotal trial, reported as total body weight reduction from baseline. These are not placebo-subtracted unless explicitly stated. Consult individual trial publications for full statistical methodology.
SURMOUNT-1 (tirzepatide) and STEP 1 (semaglutide) enrolled adults with BMI ≥30, or ≥27 with comorbidities, without type 2 diabetes — the broadest obesity indication. SELECT (semaglutide) enrolled adults with established cardiovascular disease and overweight/obesity. These populations differ significantly in baseline metabolic risk.
Responder rates follow the standard FDA thresholds used in pivotal anti-obesity trial reporting: ≥5% total body weight loss and ≥20% total body weight loss. These are the co-primary endpoints in most recent Phase 3 trials. Rates are from the drug arm only (not placebo-subtracted).
Direct cross-trial comparison should be made cautiously — trial populations, dose escalation schedules, and reporting methods differ. The rates shown are from the highest approved dose arm vs placebo in each drug's pivotal trial. For tirzepatide and semaglutide, rates come from SURMOUNT-1 and STEP 1 respectively.
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Medical disclaimer: This website is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider before starting, stopping, or changing any treatment. Prices shown are United States self-pay or list prices and vary by insurance and country.