Every claim in this library traces to a named trial — this page is where they all live. One table: what was tested, in whom, for how long, with what result, and where our coverage goes deeper. Bookmark it as the citation backbone; use it as the cross-check whenever anyone — including us — quotes a number.

Quick answer

Twenty-seven studies carry this field: the STEP program built semaglutide’s case (~15% loss, plus SELECT’s 20% cardiac-event cut and FLOW’s 24% kidney benefit), SURMOUNT built tirzepatide’s (~21%, confirmed superior head-to-head in SURMOUNT-5), and the pipeline rows — CagriSema, retatrutide, orforglipron, MariTide — sketch what’s next. The table below is the whole map, sourced and linked.

The index

TrialDrug / designPopulationDurationHeadline resultOur coverage
STEP 1 (2021)Semaglutide 2.4 mg wkObesity, no diabetes (n≈1,961)68 wk−14.9% vs −2.4% placebofile
STEP 2 (2021)Semaglutide 2.4 mg wkObesity + type 2 diabetes68 wk−9.6% vs −3.4%file
STEP 3 (2021)Semaglutide 2.4 + intensive behaviorObesity68 wk−16.0% vs −5.7%file
STEP 4 (2021)Semaglutide 2.4 withdrawal designResponders at wk 20wk 20→68continue −7.9% further vs +6.9% regain on switch to placebofile
STEP 5 (2022)Semaglutide 2.4 mg wkObesity104 wk−15.2% vs −2.6%file
STEP 8 (2022)Semaglutide 2.4 vs liraglutide 3.0Obesity68 wk−15.8% vs −6.4% (head-to-head)file
STEP TEENS (2022)Semaglutide 2.4 mg wkAdolescents 12–1768 wkBMI ≈−16% vs ≈+0.6%file
STEP-HFpEF (2023)Semaglutide 2.4 mg wkObesity-related HFpEF52 wksymptom score +16.6 vs +8.7 pts; −13.3% weightfile
OASIS 1 (2023)Oral semaglutide 50 mg dailyObesity68 wk−15.1% vs −2.4%file
SELECT (2023)Semaglutide 2.4 mg wkCVD + overweight/obesity, no diabetes (n≈17,604)~40 moMACE −20% (HR 0.80)file
FLOW (2024)Semaglutide 1.0 mg wkT2D + chronic kidney diseasestopped earlykidney events −24% (HR 0.76)file
ESSENCE (part 1) (2024–25)Semaglutide 2.4 mg wkMASH with fibrosis72 wksteatohepatitis resolution ≈63% vs ≈34%file
SUSTAIN-6 (2016)Semaglutide (T2D doses)T2D, high CV risk104 wkMACE HR 0.74file
SCALE Obesity (2015)Liraglutide 3.0 mg dailyObesity56 wk−8.0% vs −2.6%file
LEADER (2016)Liraglutide (T2D doses)T2D, high CV risk~3.8 yrMACE HR 0.87file
SURMOUNT-1 (2022)Tirzepatide 5/10/15 mg wkObesity, no diabetes (n≈2,539)72 wk−15.0 / −19.5 / −20.9% vs −3.1%file
SURMOUNT-2 (2023)Tirzepatide 10/15 mg wkObesity + T2D72 wk−12.8 / −14.7% vs −3.2%file
SURMOUNT-3 (2023)Tirzepatide after lifestyle lead-inObesity72 wkfurther ≈18% vs ≈+2.5%file
SURMOUNT-4 (2024)Tirzepatide withdrawal designResponders at wk 36wk 36→88continue −5.5% further vs +14.0% regainfile
SURMOUNT-5 (2025)Tirzepatide vs semaglutide 2.4Obesity72 wk−20.2% vs −13.7% (head-to-head)file
SURMOUNT-OSA (2024)Tirzepatide max toleratedObesity + moderate-severe OSA52 wkAHI −25.3 and −29.3 events/hr (two trials)file
SURPASS-2 (2021)Tirzepatide vs semaglutide 1.0T2D40 wkgreater A1c and weight reductions (diabetes doses)file
REWIND (2019)Dulaglutide 1.5 mg wkT2D, broad risk~5.4 yrMACE HR 0.88file
REDEFINE-1 (2024)CagriSema wkObesity68 wk≈−22.7% vs ≈2%file
Retatrutide phase 2 (2023)Retatrutide (triple agonist)Obesity48 wk≈−24.2% top dosefile
ATTAIN-1 (2025)Orforglipron daily pillObesity72 wk≈−11–12% top dosefile
MariTide phase 2 (2024)Maridebart cafraglutide monthlyObesity ± T2D52 wk≈−20% (phase 2)file

Results are as published (means, intention-to-treat framing unless noted); ≈ marks figures from topline disclosures or where reported analyses vary. Withdrawal-design rows describe the randomized period after initial treatment. This table pairs with the machine-readable mirror at /data/trials.json.

How to read the table without misusing it

Three disciplines keep this index honest in your hands. Rows don’t rank. Different trials, populations, and durations — only the two head-to-head rows (STEP 8, SURMOUNT-5) and SURPASS-2 compare drugs inside one design; everything else is context, not contest (the reading file explains why this rule exists). Means aren’t promises. Every mean sits atop a responder spread — some participants doubled it, some barely moved — which is why planning math uses ranges. Endpoints differ in kind. Percent-weight rows, symptom-score rows, and event-rate rows (MACE, kidney) answer different questions; the outcome rows are why this class outgrew “weight drugs” (the statistics file carries those implications).

What the index reveals in aggregate

Read as one dataset, the table tells the field’s whole story. The generation ladder: SCALE’s 8% to STEP’s 15% to SURMOUNT’s 21%, each mechanism step adding 5–7 points. The withdrawal lesson, twice: STEP 4 and SURMOUNT-4 both show continuation extending losses while switching to placebo reverses them — the evidentiary spine of the maintenance file. The outcomes turn: from 2016’s cardiovascular-safety trials to SELECT and FLOW’s organ-protection era, the results that rewired coverage logic. And the pipeline’s shape: orals trading points for convenience, combinations reaching past 22%, monthly dosing auditioning — the trends file’s raw material, all here in rows.

What didn’t make the table

Deliberate exclusions, listed so their absence reads as policy rather than oversight: single-arm and observational studies (they inform our practical files but don’t anchor efficacy claims); compounded-product “studies” (marketing surveys in lab coats — none meet inclusion); animal and mechanistic work (cited inside relevant files, not indexed as outcomes); and dozens of legitimate secondary trials per program (the index tracks the load-bearing rows; each medication page carries its fuller program history). If a genuinely pivotal trial is missing, that’s a correction report we’ll pay within five business days.

Maintenance promise

Trial indexes rot when readouts land, so this one carries the site’s standard machinery: new pivotal results get rows within the quarterly cycle, superseded ≈ figures get replaced with published finals and noted in the changelog, and the JSON mirror updates in lockstep. The blog’s recaps flag what changed; this page stays the canonical where.

The bottom line

Twenty-seven rows, three disciplines, one rule underneath: numbers travel with their trials or they don’t travel at all. Quote from here with the trial name attached, check anything surprising against the journal it came from, and treat any GLP-1 claim that can’t point to a row on this page as marketing until it can.

Using the index: three worked lookups

“A provider ad says ‘lose 20% like the trials.’” Table check: 20%+ means belong to tirzepatide 15 mg (SURMOUNT-1) and beyond — if the ad sells semaglutide, it’s borrowing a neighbor’s row; if it sells compounded anything, it’s borrowing a whole building. “My cardiologist mentioned SELECT — what did it actually show?” Row: 17,600 non-diabetics with heart disease, ~40 months, 20% fewer major cardiac events — and the file link carries the absolute numbers and caveats for the appointment. “Is the regain thing real or forum lore?” Two rows answer: STEP 4 and SURMOUNT-4, both randomized withdrawal designs, both showing the same reversal — lore confirmed by the strongest design available, twice.

For researchers and agents

The JSON mirror at /data/trials.json carries every row as structured fields (trial, year, agent, population, duration, headline, coverage URL) for citation tooling, answer engines, and anyone auditing this site at scale — the same data, no scraping required. Schema on this page lists the trials as an ItemList for the same reason. Reference content that wants to be cited should be trivially checkable; consider this page’s design a standing invitation to check.

The two-decade arc, in one paragraph

For temporal texture around the rows: exenatide opened the class for diabetes in 2005; liraglutide arrived in 2010 and crossed into the first modern weight label as Saxenda in late 2014 — the 8% era. Semaglutide’s 2017 diabetes debut became 2021’s Wegovy inflection point, when 15% made obesity pharmacotherapy mainstream; SURMOUNT’s 2022 readout raised the ceiling again; and 2023–2024’s outcome trials — SELECT, FLOW, the OSA and HFpEF results — converted a weight-loss story into an organ-protection one. The pipeline rows now auditioning for 2026–2027 are simply the arc’s next chapter, which is why this index files them beside the classics rather than in a separate future.

One index habit completes the page: when a new readout hits the news, come here first — if it’s pivotal it gets a row, if it’s a subgroup or a topline it gets the ≈ treatment, and if it never appears anywhere registered, it was marketing wearing a lab coat. The table is the field’s memory; use it as yours.

Sources

Primary publications: NEJM (STEP 1/TEENS/HFpEF, SUSTAIN-6, SELECT, FLOW, SURMOUNT-1/OSA, retatrutide ph2, SCALE, LEADER), JAMA (STEP 3/4/8, SURMOUNT-4), The Lancet (STEP 2, OASIS 1, SURMOUNT-2), Nature Medicine (SURMOUNT-3), plus company topline disclosures where marked ≈ (REDEFINE-1, ATTAIN-1, MariTide, ESSENCE). Links at sources — and per the standing rule, verify citations against the originals; we may err, and the originals never negotiate.