VK2735 vs Tirzepatide (2026): Dual GLP-1/GIP Agonists Compared on Trials, Dosing and Status
VK2735 vs tirzepatide: same GLP-1/GIP targets, 14.7% at 13 weeks vs 20.9% at 72 weeks, plus oral and monthly dosing data. See how the two compare in 2026.
Research reference only. The information in this article is a summary of peer-reviewed scientific literature. It does not constitute medical advice and is not intended to guide human use. See our full disclaimer.
VK2735 vs tirzepatide is the most direct like-for-like comparison in the incretin pipeline: both compounds activate the same two receptors, GLP-1 and GIP, but one is an investigational Phase 3 candidate from Viking Therapeutics and the other is the approved dual agonist from Eli Lilly that defined the class. Because the receptor pair is identical, differences between the two come down to molecular design, dosing interval, formulation and the maturity of each evidence base rather than mechanism category.
Research reference only. All information on this page is a summary of peer-reviewed scientific literature and does not constitute medical advice. See individual library profiles for full compound data.
Quick Answer: VK2735 and tirzepatide are both dual GLP-1/GIP receptor agonists; VK2735 produced up to 14.7% mean weight loss at 13 weeks in Phase 2 VENTURE, while tirzepatide produced up to 20.9% at 72 weeks in Phase 3 SURMOUNT-1. No head-to-head trial exists, and VK2735's 78-week Phase 3 VANQUISH data are expected in 2027.
TL;DR:
- Same receptor pair (GLP-1 + GIP), different molecules, developers and development stages.
- Tirzepatide is FDA-approved with 72-week obesity data; VK2735 is investigational with 13-week peer-reviewed data and 33-week topline data.
- VK2735 is being studied as both a weekly injection and a once-daily oral tablet, with oral Phase 3 SUNRISE trials started in October 2026.
- Early VK2735 maintenance data explored every-other-week and monthly dosing after weekly induction, an interval tirzepatide has not been tested at.
- Cross-trial figures differ in duration and design, so they cannot be read as a ranking.
At a glance
| Feature | VK2735 | Tirzepatide |
|---|---|---|
| Developer | Viking Therapeutics | Eli Lilly |
| Receptor targets | GLP-1R + GIPR agonist | GLP-1R + GIPR agonist |
| Most advanced stage | Phase 3 (VANQUISH-1, VANQUISH-2; oral SUNRISE) | Approved (FDA, EMA) |
| Headline weight-loss figure | Up to 14.7% at 13 weeks (Phase 2 VENTURE) | Up to 20.9% at 72 weeks (Phase 3 SURMOUNT-1) |
| Dosing interval studied | Weekly SC; every-other-week and monthly maintenance explored; daily oral | Weekly SC |
| Peer-reviewed obesity trial | Obesity, 2026 | New England Journal of Medicine, 2022 |
VK2735: Mechanism and evidence base
VK2735 is a synthetic peptide engineered to activate both the glucagon-like peptide-1 receptor and the glucose-dependent insulinotropic polypeptide receptor. GLP-1 receptor signalling in the hypothalamus and brainstem is associated with satiety and slowed gastric emptying, while GIP receptor engagement contributes glucose-dependent insulin secretion and has been studied for effects on adipocyte lipid handling and on the tolerability of GLP-1 agonism. Fatty-acid conjugation extends its half-life to support weekly subcutaneous administration, and a separate oral tablet uses an absorption-enhancing excipient platform. Chemistry and trial details are on the VK2735 library profile.
The primary peer-reviewed dataset is the Phase 2 VENTURE study (PMID 41508550), a 13-week, randomized, double-blind, placebo-controlled trial in adults with obesity. Weekly subcutaneous VK2735 produced dose-dependent weight loss of up to 14.7% from baseline versus placebo, and the authors reported that primary and secondary endpoints were met. Adverse events were primarily gastrointestinal and became less frequent with continued dosing. A separate Phase 2 trial of the oral tablet (NCT06828055) reported up to 12.2% mean weight loss at 13 weeks.
In September 2026, Viking reported topline results from an exploratory maintenance study (NCT07838740) in about 180 adults with a BMI of 30 or higher. After 21 weeks of weekly induction at 15–22.5 mg, mean weight loss was roughly 16% to 19%. Continuous weekly dosing at 17.5 mg reached 21.7% at week 33 with no reported plateau. Participants switched to every-other-week dosing retained up to 97% of their week-21 loss, and those switched to monthly dosing retained up to 90%, compared with 61% for those switched to placebo. These figures are company-reported and not yet peer reviewed.
The pivotal programme is VANQUISH-1 (NCT07104500, about 4,500 participants with obesity or overweight) and VANQUISH-2 (NCT07104383, about 1,000 participants with type 2 diabetes). Both are 78-week placebo-controlled trials with enrollment complete. On October 14, 2026, Viking initiated two 68-week oral Phase 3 trials, SUNRISE-1 (NCT07868835) and SUNRISE-2 (NCT07868939), testing once-daily tablets at 27.5, 35 or 55 mg.
Tirzepatide: Mechanism and evidence base
Tirzepatide is a 39-amino-acid peptide based on the native GIP sequence, modified to also activate the GLP-1 receptor and conjugated to a C20 fatty diacid that binds albumin. The result is a half-life of roughly five days, supporting once-weekly subcutaneous administration. Pharmacology studies describe it as an imbalanced co-agonist: it engages the GIP receptor with affinity similar to native GIP but the GLP-1 receptor more weakly than native GLP-1, and shows bias toward cAMP signalling over beta-arrestin recruitment at the GLP-1 receptor. Mechanism detail is on the tirzepatide library profile.
The obesity dataset centres on SURMOUNT-1 (PMID 35658024), a 72-week randomized, double-blind, placebo-controlled trial in 2,539 adults with obesity or overweight without diabetes. Once-weekly tirzepatide at 5, 10 and 15 mg produced mean weight reductions of 15.0%, 19.5% and 20.9%, versus 3.1% with placebo. In type 2 diabetes, SURPASS-1 (PMID 34186022) reported HbA1c reductions of 1.87–2.07 percentage points at 40 weeks as monotherapy.
Post-approval research has extended the literature into real-world settings. A 2026 single-centre cohort from the United Arab Emirates (PMID 42029986) reported median weight reduction of 22.6% in participants who persisted with treatment beyond one year, versus 8.1% in those treated for one year or less, with parallel differences in lipid, hepatic and renal markers. This kind of persistence-stratified observational data does not yet exist for VK2735.
Side-by-side comparison
| Parameter | VK2735 | Tirzepatide |
|---|---|---|
| Molecular class | Synthetic dual incretin peptide, fatty-acid conjugated | GIP-based dual agonist peptide, C20 diacid conjugated |
| Receptor activity | GLP-1R and GIPR agonist | GLP-1R and GIPR agonist (GIP-favouring) |
| Half-life | Not fully published; sponsor reports support for sub-weekly maintenance exploration | ~5 days |
| Routes studied | Subcutaneous; oral tablet | Subcutaneous |
| Longest reported efficacy data | 33 weeks (maintenance study, topline) | 72 weeks (SURMOUNT-1); 3-year prediabetes extension |
| Pivotal programme | VANQUISH (SC), SUNRISE (oral) | SURPASS (T2D), SURMOUNT (obesity) |
| Regulatory status (US) | Investigational | FDA-approved |
| Primary research applications | Dosing-interval and oral-formulation studies | Reference dual agonist for incretin pharmacology |
Half-life values for a wider set of incretin compounds can be compared on the peptide half-life chart.
Differential research applications
Tirzepatide is typically selected when a study needs a well-characterised dual agonist reference. Its receptor pharmacology, pharmacokinetics and long-duration trial record make it the default comparator for any new GLP-1/GIP molecule, and the SURMOUNT-5 trial, which compared it with semaglutide, is often cited as evidence that adding GIP agonism changes the weight-loss ceiling relative to selective GLP-1 agonism.
VK2735 is of interest for questions tirzepatide's dataset does not answer. The first is dosing frequency: the September 2026 maintenance study is among the first to test monthly administration of a dual incretin agonist after weekly induction. The second is formulation, since VK2735 is one of a small number of dual agonists with an oral tablet in Phase 3. The third is whether a different molecular balance between the two receptors changes tolerability, a question also being explored with signal-biased dual agonists.
For researchers placing both compounds in the wider pipeline, the next mechanistic step up is retatrutide, which adds glucagon receptor agonism, and the comparison with single-receptor agonists runs through liraglutide and semaglutide. Registered trial status for all of these compounds can be tracked in the clinical trial tracker.
The main limitation is that no trial has compared VK2735 and tirzepatide directly. The 13-week and 72-week headline figures reflect different trial lengths, baseline populations, titration schedules and estimands, so the gap between them should not be read as a difference in efficacy.
Regulatory and compounding status
Tirzepatide is FDA-approved for type 2 diabetes, chronic weight management and obstructive sleep apnoea in adults with obesity, and is authorised by the EMA. It was removed from the FDA drug shortage list in late 2024, ending the shortage-based allowance for compounded copies. It is not a named substance on the WADA Prohibited List.
VK2735 has no regulatory approval in any jurisdiction. As an investigational compound it is not eligible for 503A or 503B compounding, and access is limited to registered clinical trials. Under WADA's S0 category, covering pharmacological substances without approval for human therapeutic use, it is prohibited at all times in sport. VANQUISH topline data are expected in 2027.
Cited studies
- PMID 41508550: "Weekly Subcutaneous VK2735, a GIP/GLP-1 Receptor Dual Agonist, for Weight Management: Phase 2, Randomized, 13-Week VENTURE Study" (Obesity, 2026). https://doi.org/10.1002/oby.70106
- PMID 35658024: "Tirzepatide Once Weekly for the Treatment of Obesity" (New England Journal of Medicine, 2022). https://doi.org/10.1056/NEJMoa2206038
- PMID 34186022: "Efficacy and safety of a novel dual GIP and GLP-1 receptor agonist tirzepatide in patients with type 2 diabetes (SURPASS-1)" (Lancet, 2021). https://doi.org/10.1016/S0140-6736(21)01324-6
- PMID 42029986: "Persistence-Dependent Effectiveness of Tirzepatide on the Cardio-Metabolic-Kidney Syndrome Outcomes in Obesity: Real-World Evidence from the United Arab Emirates" (Diabetes Therapy, 2026). https://doi.org/10.1007/s13300-026-01868-2
- Trial registrations: NCT07104500, NCT07104383, NCT07838740, NCT07868835, NCT07868939 (ClinicalTrials.gov).
Frequently asked questions
Q: What is the difference between VK2735 and tirzepatide?
A: Both activate the GLP-1 and GIP receptors, so they share a mechanistic class. Tirzepatide is an approved weekly injectable from Eli Lilly, while VK2735 is an investigational Viking Therapeutics compound studied as both a weekly injection and a daily oral tablet.
Q: Tirzepatide vs VK2735: which produced more weight loss in trials?
A: Tirzepatide reached up to 20.9% at 72 weeks in SURMOUNT-1, and VK2735 reached up to 14.7% at 13 weeks in VENTURE and 21.7% at 33 weeks in a topline maintenance study. The trials differ in length and design, and no head-to-head comparison has been run.
Q: Is VK2735 a copy of tirzepatide?
A: No. VK2735 is a separate molecule with its own sequence and conjugation chemistry; it only shares the same two receptor targets. Its receptor balance and pharmacokinetics have not been shown to match tirzepatide's.
Q: Is there an oral version of VK2735?
A: Yes. An oral tablet reported up to 12.2% weight loss at 13 weeks in Phase 2, and two 68-week Phase 3 SUNRISE trials began in October 2026. Tirzepatide has no oral formulation in its approved labelling.
Q: When will VK2735 Phase 3 results be available?
A: VANQUISH-1 and VANQUISH-2 are 78-week trials with enrollment complete, and topline data are expected in 2027. Oral SUNRISE results would follow later given their October 2026 start.
See also:
- VK2735 vs Retatrutide: Which Investigational Incretin Agonist Leads the Injectable Obesity Pipeline?: compares VK2735 with the leading triple agonist.
- VK2735 vs Semaglutide (2026): Phase 3 Dual GLP-1/GIP Agonist vs the GLP-1 Benchmark: the dual-versus-selective comparison for the same compound.
- Retatrutide vs Tirzepatide: Triple vs Dual Agonist Mechanism Comparison: how tirzepatide compares with a compound that adds glucagon agonism.
For laboratory research purposes only. Not for human or animal consumption. Compounds described are not approved by the FDA for human or veterinary use unless explicitly stated.