VK2735 is Viking Therapeutics’ investigational dual GLP-1/GIP receptor agonist for obesity, developed in parallel as a once-weekly subcutaneous injection and a once-daily oral tablet. In its published phase 2 trial, the injectable form produced up to 14.7% mean weight loss over 13 weeks; the oral tablet produced up to 12.2%. A separate maintenance-dosing study found less-frequent dosing preserved up to 97% of that loss. It is not approved anywhere and is now in phase 3 trials for the injectable form.
Research snapshot
| Peptide category | Metabolic / incretin — dual GIP/GLP-1 receptor agonist |
| Primary research interest | Obesity and weight management; type 2 diabetes population included in one Phase 3 arm |
| Highest available evidence | Published human clinical trial data (Phase 2, peer-reviewed) |
| Human research available | Yes — Phase 1 complete, Phase 2 complete (both SC and oral forms) and published/reported, a maintenance-dosing study reported, Phase 3 underway |
| Development status | Phase 3 (VANQUISH-1, VANQUISH-2 for the injectable; oral tablet advancing toward Phase 3 per company statements, no oral Phase 3 NCT number confirmed as of this review) |
| Regulatory status | Not approved anywhere |
| Last reviewed | September 27, 2026 |
Technical identity
| Primary name | VK2735 |
| Alternative names | None identified beyond the development code |
| Peptide sequence | Not publicly disclosed |
| Amino-acid length | Not publicly disclosed |
| Molecular formula | Not publicly disclosed |
| Molecular weight | Not publicly disclosed |
| CAS Registry Number | Not reliably established — no primary or regulatory source located |
| PubChem CID | Not established |
| UNII | Not available |
| DrugBank ID | Not available |
| Chemical modifications | Not publicly disclosed; described only in general terms as a peptide-based dual agonist |
| Peptide class | Dual GIP/GLP-1 receptor agonist (injectable and oral forms in development) |
| Primary biological target | GLP-1 receptor and GIP receptor, both agonized |
| Developer or originator | Viking Therapeutics, Inc. |
| Development status | Phase 3 (injectable); Phase 2 complete, Phase 3 advancing (oral). No chemical database record (PubChem, DrugBank, CAS) could be located as of this review |
What is VK2735?
VK2735 is an experimental weight-management drug from Viking Therapeutics, a California biotech. It belongs to the same class as tirzepatide and retatrutide: a dual agonist, designed to activate two gut-hormone receptors, GLP-1 and GIP, at once rather than just one, on the theory that hitting both produces more weight loss than GLP-1 alone.
What sets VK2735 apart in Viking’s own program is that it is being developed in two forms at once, a once-weekly injection and a once-daily tablet, tested in parallel. Most competitors choose one route first and test the other years later, and an oral incretin drug that actually works well is still a genuinely unsolved problem in this field, since peptides are normally destroyed by stomach acid. Viking has also specifically studied what happens after the initial weight-loss phase: a maintenance-dosing study found that switching from weekly injections to every-other-week or monthly dosing preserved most of the weight already lost.
Viking is a mid-sized biotech, not one of the large pharmaceutical companies already selling an approved obesity drug, so VK2735’s path to market depends on how it performs in the trials now running. As of this review, no chemical identity information (formula, sequence, CAS number) has been made public for VK2735; everything known comes from clinical trial results and Viking’s own disclosures, not from a published structure paper. The compound moved into phase 1 human testing in 2022–2023, cleared phase 2 for both the injectable and oral forms by 2025, and is now in phase 3 trials for the injectable form (VANQUISH-1 and VANQUISH-2), with an oral phase 3 program stated by the company but not yet confirmed as a registered trial.
How does it work?
Plain-English explanation
VK2735 mimics two of the body’s own gut hormones that get released after eating and normally signal fullness to the brain, while also affecting insulin release and how the stomach empties. Activating both signaling systems at once instead of just one is the strategy, already proven out by tirzepatide, that the theory says produces a stronger and more consistent drop in appetite than a single-hormone drug.
Technical explanation
Viking describes VK2735 as binding both the GLP-1 receptor and the GIP receptor. One trial-registry source reports binding affinities of IC50 188 nM at the GLP-1 receptor and IC50 325 nM at the GIP receptor, but the same source explicitly labels these figures “unpublished data,” so they should be treated as provisional rather than settled pharmacology. No peer-reviewed receptor-selectivity study of the kind published for compounds like retatrutide has been located for VK2735, and its exact chemical modification strategy, including whether it uses a fatty-acid conjugate the way semaglutide and tirzepatide do, has not been disclosed in any source checked for this entry.
Potential benefits and research applications
Weight reduction in obesity and overweight
What is being investigated: mean body-weight reduction over 13 weeks (phase 2) and 78 weeks (phase 3, ongoing) in adults with obesity or overweight plus at least one weight-related condition. Evidence: the phase 2 VENTURE trial (subcutaneous), published in Obesity (Bays et al., 2026), and the phase 2 VENTURE-Oral Dosing trial (tablet), reported via company press release and presented at the European Congress on Obesity 2026. Strength: registered, randomized, placebo-controlled phase 2 human trial evidence, one of the strongest tiers this site recognizes, though phase 3 is what will establish long-term safety and durability at scale. Limitation: 13 weeks is short for a chronic weight-management drug, and no long-term (1+ year) human data exists yet for VK2735 in any form.
Weight-loss maintenance with less frequent dosing
What is being investigated: whether weight loss achieved during weekly induction dosing can be preserved with less frequent, every-other-week or monthly, maintenance dosing. Evidence: the VK2735-102 maintenance study, reported via Viking’s SEC filing and investor press release (2026-09-22), roughly 180 adults with obesity, a 21-week weekly induction phase titrated to 15.0, 17.5, 20.0, or 22.5 mg, followed by a 12-week maintenance phase comparing every-other-week and monthly dosing against continued weekly dosing and placebo. Strength: a real, sizeable, randomized trial targeting a genuinely important practical question for a chronic-use drug; company-reported, not yet peer-reviewed. Limitation: only 12 weeks of maintenance-phase data exists so far, so whether retention holds up over a full year or longer is unknown.
Glycemic effects in people with type 2 diabetes
What is being investigated: VANQUISH-2, the phase 3 arm enrolling participants with type 2 diabetes (HbA1c 7–11%), is testing the injectable form in this population. Evidence: the trial is registered and actively running (ClinicalTrials.gov NCT07104383); no results have been published yet. Strength: not established, since the trial has not read out. Limitation: nothing is known yet about glycemic outcomes specifically, and tirzepatide-like diabetes efficacy should not be assumed to carry over.
What dosage information circulates?
Figures in this section summarize amounts and schedules reported in published research or circulating online. Their inclusion documents what is reported and does not establish that a regimen is verified, safe, effective, or appropriate.
| Reported use or research objective | Route reported | Amount reported | Frequency reported | Reported duration | Evidence or source category |
|---|---|---|---|---|---|
| Weight management, Phase 2 dose-finding (VENTURE) | Subcutaneous | 2.5 mg, 5 mg, 10 mg, 15 mg | Once weekly | 13 weeks | Published human clinical trial (Bays et al., Obesity 2026) |
| Weight management, Phase 2 dose-finding, oral (VENTURE-Oral Dosing) | Oral tablet | 15 mg, 30 mg, 60 mg, 90 mg, 120 mg | Once daily | 13 weeks | Company-reported human clinical trial (press release; full peer-reviewed publication not yet located) |
| Weight-loss maintenance (VK2735-102) | Subcutaneous | Induction titrated to 15.0, 17.5, 20.0, or 22.5 mg; maintenance every-other-week (e.g. 10.0 mg EOW) or monthly (e.g. 17.5 mg monthly) | Weekly induction (21 weeks), then EOW or monthly maintenance | 33 weeks total | Company-reported human clinical trial (SEC filing) |
| Weight management, Phase 3 (VANQUISH-1, no diabetes) | Subcutaneous | Not disclosed in public sources at time of review | Once weekly | 78 weeks | Registered human trial, unpublished |
| Weight management, Phase 3 (VANQUISH-2, with type 2 diabetes) | Subcutaneous | Not disclosed in public sources at time of review | Once weekly | 78 weeks | Registered human trial, unpublished |
| Practitioner and community-reported protocols | Not applicable | Not consistently reported — no vendor/gray-market dosing convention exists distinct from the registered-trial doses | Not applicable | Not applicable | Trial-participant self-report only (r/VK2735, r/Vikingtherapeutics); not a gray-market protocol |
Amounts studied in human research
The published phase 2 VENTURE trial tested subcutaneous doses of 2.5, 5, 10, and 15 mg once weekly for 13 weeks. The phase 2 VENTURE-Oral Dosing trial tested oral tablet doses of 15, 30, 60, 90, and 120 mg once daily, also for 13 weeks. The VK2735-102 maintenance study titrated participants up to 15.0, 17.5, 20.0, or 22.5 mg weekly over 21 weeks of induction, then compared every-other-week dosing (for example 17.5 mg weekly induction stepping down to 10.0 mg every other week) and monthly dosing (for example 17.5 mg monthly) over a further 12 weeks. Doses for the ongoing phase 3 trials, VANQUISH-1 and VANQUISH-2, have not been disclosed publicly as of this review.
Amounts studied in animal research
Not identified in the sources reviewed for this page. Viking’s public disclosures on VK2735 have focused on the human trial program rather than published preclinical dosing.
Practitioner and community-reported protocols
Not consistently reported, and that is expected, since VK2735 has no legitimate commercial supply chain the way many older research peptides do. There is genuine online community activity, including subreddits such as r/VK2735 and r/Vikingtherapeutics, but it consists of people describing their own experience as participants in Viking’s actual clinical trials, not a vendor-sourced dosing convention. That is trial-participant self-report, not a gray-market protocol, and none of it substitutes for the registered-trial data above. Because Viking has never sold or distributed VK2735 to the public, any product sold online under this name is being represented as something Viking itself has never released outside its clinical trial network.
What circulates E5
| Reported use | Route | Amount reported | Frequency | Reported length |
|---|---|---|---|---|
| Weight management, phase 2 dose-finding (VENTURE) | Subcutaneous injection | 2.5 mg, 5 mg, 10 mg, or 15 mg | Once weekly | 13 weeks |
| Weight management, phase 2 dose-finding, oral (VENTURE-Oral Dosing) | Oral tablet | 15 mg, 30 mg, 60 mg, 90 mg, or 120 mg | Once daily | 13 weeks |
| Weight-loss maintenance (VK2735-102) | Subcutaneous injection | Induction titrated to 15.0-22.5 mg weekly; maintenance at every-other-week (e.g. 10.0 mg EOW) or monthly (e.g. 17.5 mg monthly) | Weekly induction, then every-other-week or monthly maintenance | 33 weeks total (21-week induction + 12-week maintenance) |
| Weight management, phase 3 (VANQUISH-1, VANQUISH-2) | Subcutaneous injection | Not disclosed in public sources at time of review | Once weekly | 78 weeks |
| Community, forum, or vendor protocol | Not applicable | No independent dosing convention identified; Viking has never sold VK2735 to the public | Not applicable | Not applicable |
No established or reliably sourced consumer dosing information was identified. Every dosage figure documented on this page comes from Viking Therapeutics' own registered clinical trials or SEC filings; there is no approved product, and Viking has never sold or distributed VK2735 outside its clinical trial network.
Online community activity around VK2735 (including subreddits such as r/VK2735 and r/Vikingtherapeutics) consists of trial participants discussing their own experience in Viking's registered trials, not an independent vendor or gray-market dosing convention. No such convention was identified during this review.
Recorded as an observation about what is published elsewhere. No figure here is a dose, a protocol, or a recommendation, and nothing in this section is evidence that any amount is safe or effective.
Side effects, risks, and limitations
Gastrointestinal side effects (nausea, vomiting, constipation) were the most commonly reported adverse events in both the subcutaneous and oral phase 2 trials, and rates rose with dose in both formulations. In the subcutaneous VENTURE trial, GI events occurred in 51% (2.5 mg) to 83% (15 mg) of participants, with discontinuation rates of 6% (2.5 mg) to 20% (15 mg); nausea was the single most common event (36.6% overall), followed by constipation and vomiting. In the oral VENTURE-Oral Dosing trial, nausea occurred in 58% of VK2735-treated participants versus 48% on placebo, and vomiting in 26% versus 10%, with adverse-event discontinuation at 20% overall versus 13% on placebo, rising from 20% at the lowest doses to 38% at 120 mg. The maintenance study reported GI side effects “near placebo levels” on the less-frequent dosing schedules, per company disclosure, though exact percentages were not detailed in the sources reviewed.
This pattern, GI side effects rising with dose and discontinuation rates rising alongside them, is standard for this drug class and mirrors what has been published for tirzepatide and semaglutide; it is not a distinct safety signal for VK2735 specifically. No long-term safety data exists yet beyond the 33-week maintenance study, and concerns tracked for the broader incretin class, such as pancreatitis or thyroid C-cell tumor risk, have not been specifically reported on for VK2735 in any source reviewed here. Because VK2735 has no legitimate retail or research-use supply chain, anything purchased under this name from an online vendor carries the added risk of mislabeling, incorrect concentration, or being an entirely different substance, on top of whatever risks the real molecule itself carries.
Regulatory and developmental status
VK2735 is not approved for any use anywhere. The subcutaneous form is in phase 3 development, VANQUISH-1 for participants without type 2 diabetes and VANQUISH-2 for participants with it, both fully enrolled as of 2026 with primary completion targeted for mid-2027. The oral tablet form completed phase 2 in 2025 and, per company statements and SEC filings, is advancing toward phase 3, though no oral phase 3 trial could be located in the ClinicalTrials.gov registry as of this review; this should be read as advancing per company disclosure rather than an active registered trial. No FDA Fast Track, Breakthrough Therapy, or other expedited-review designation was identified in any source checked. Date verified: 2026-09-25.
Frequently asked questions
What is VK2735?
An investigational dual GLP-1/GIP receptor agonist from Viking Therapeutics, developed as both a weekly injection and a daily tablet for obesity. It is not approved anywhere.
How does it work?
It activates two gut-hormone receptors, GLP-1 and GIP, that together reduce appetite and affect digestion and insulin release, the same general mechanism as tirzepatide.
What dosage has been studied?
In the published phase 2 injectable trial: 2.5, 5, 10, and 15 mg once weekly. In the phase 2 oral trial: 15, 30, 60, 90, and 120 mg once daily. A maintenance study titrated up to 22.5 mg weekly before testing every-other-week and monthly follow-up dosing. Phase 3 doses have not been disclosed.
How much weight loss has been shown?
Up to 14.7% mean weight loss at 15 mg weekly (injectable, 13 weeks) and up to 12.2% at 120 mg daily (oral, 13 weeks), both versus roughly 1.7–2.3% on placebo.
Do you have to keep injecting every week forever?
Not necessarily, based on early data. Viking’s maintenance study found every-other-week dosing preserved up to 97% of weight loss and monthly dosing up to 90%, over a 12-week follow-up period.
Is VK2735 the same as tirzepatide?
No. It is a different molecule from a different company, but it shares the same general mechanism of dual GLP-1/GIP agonism.
Has it been studied in humans?
Yes. Phase 1 and phase 2 are complete for both the injectable and oral forms, a maintenance-dosing study has reported results, and phase 3 is underway for the injectable form.
What side effects have been reported?
Mostly gastrointestinal, nausea, vomiting, and constipation, increasing with dose, consistent with other drugs in this class.
Is VK2735 approved?
No, in any country, for any use.
What remains unknown?
Long-term safety and durability beyond 33 weeks, the actual phase 3 dose or doses, whether the oral form will reach phase 3 as a registered trial, and the compound’s full chemical identity, none of which has been published.
Bottom line
VK2735 is one of the more evidence-backed compounds in the obesity drug pipeline right now. Its phase 2 injectable data is peer-reviewed and published, not just a press release, and its dose-response pattern is exactly what would be expected from a drug in this class. What is genuinely published: up to 14.7% weight loss at the top injectable dose and up to 12.2% at the top oral dose, both over 13 weeks. What is strong but still company-reported: a maintenance study showing most of that weight loss holds up on much less frequent dosing, and the oral phase 3 program’s stated existence. What is completely unknown: the actual chemical structure, the phase 3 dosing regimen, and anything about long-term safety or durability beyond 33 weeks, which will not be fully answered until VANQUISH-1 and VANQUISH-2 read out around mid-2027. It is not approved anywhere and has no legitimate retail supply chain.