History

VK2735 advanced through a Phase 2 subcutaneous trial (VENTURE, 176 randomized, results published in Obesity in 2026) into a Phase 3 program (VANQUISH) initiated June 25, 2025, with VANQUISH-1 (obesity) and VANQUISH-2 (type 2 diabetes) completing enrollment in late 2025 and early 2026. A separate oral tablet completed Phase 2 (VENTURE-Oral), with company top-line results in August 2025 and conference data presented at the European Congress on Obesity (ECO) in May 2026.

VK2735 is an investigational obesity drug from Viking Therapeutics. It belongs to the incretin class — the same broad family as semaglutide and tirzepatide — and has generated a lot of attention because its early human data look strong and because Viking is developing both an injectable and an oral version. That said, “early human data look strong” is exactly where this compound sits: it is not approved by any regulator, it is not a prescription medicine, and its long-term safety has not been established. Anything sold off-trial as “VK2735” is unapproved and uncharacterized.

What it is

VK2735 is a dual agonist of the GLP-1 and GIP receptors. Activating both incretin receptors suppresses appetite, slows gastric emptying, and improves glycemic and metabolic control — the combination that produces weight loss. Mechanistically it is in the same class as tirzepatide.

Viking is developing it in two formulations: a weekly subcutaneous injection and a once-daily oral tablet. It is being investigated for obesity/overweight and metabolic disease.

One point worth stating plainly: VK2735 is not a muscle-building or “anabolic” agent. There is no myostatin or growth-factor mechanism here. Any marketing that frames it as a muscle compound is inventing a claim the science does not support.

The claims

You will see VK2735 promoted as a next-generation, “tirzepatide-but-better” weight-loss compound, sometimes with an oral version pitched as a needle-free alternative. Some vendor claims go further — asserting specific per-dose tolerability numbers, or even that it has been moved into a banned anti-doping category. Below is what the actual evidence supports and where the claims outrun it.

What the evidence actually shows

Subcutaneous VENTURE (Phase 2) — peer-reviewed and published. This is the strongest human evidence to date. The randomized, double-blind, placebo-controlled, 13-week dose-ranging trial (NCT06068946) randomized 176 participants (174 in the modified intention-to-treat analysis) across 2.5 / 5.0 / 10 / 15 mg arms plus placebo. The primary endpoint — percent change in body weight at Week 13 — was met. At the 15 mg dose, mean weight change was −14.7% (95% CI −16.11, −13.38) versus −1.7% for placebo, with no weight plateau by week 13. Results were published in Obesity (Silver Spring) in 2026.

Oral VENTURE-Oral (Phase 2) — company-reported and conference data, not yet a peer-reviewed paper. The 13-week trial enrolled 280 adults across six once-daily dose arms (15 / 30 / 60 / 90 / 120 mg) plus placebo (~40 each). Top-line results were announced in August 2025 and presented at ECO 2026 in May 2026. Reported mean weight loss reached up to −12.2% at the top dose versus −1.3% placebo, with up to 97% of participants achieving ≥5% loss and up to 80% achieving ≥10%. Because these are company/conference figures without a confirmed journal publication, the per-dose numbers should be treated as preliminary.

Phase 3 is underway but has not read out. The VANQUISH program began June 25, 2025. VANQUISH-1 (obesity, ~4,650 adults) completed enrollment November 19, 2025; VANQUISH-2 (type 2 diabetes with obesity/overweight, ~1,000 adults, weekly subcutaneous) completed enrollment March 26, 2026. Both run 78 weeks of dosing (7.5 / 12.5 / 17.5 mg vs placebo). No Phase 3 efficacy result has been reported as of June 2026. There are no head-to-head trials against tirzepatide or semaglutide, and no long-term outcome data.

Legal and regulatory status

VK2735 is investigational only and not approved anywhere. It is not available as a prescription drug.

On anti-doping: GLP-1 / GIP receptor agonists are not prohibited by WADA. Under the WADA 2026 update, markers of semaglutide and tirzepatide are on the 2026 Monitoring Program (in- and out-of-competition). Monitoring is used to detect misuse patterns and does not by itself constitute an anti-doping rule violation. As an unlisted investigational incretin agonist of the same class, VK2735 is not on the Prohibited List — though monitoring-program status can change year to year, so athletes should treat these substances cautiously.

A circulating vendor claim that GLP-1s were moved to “full S4 prohibition” in 2026 is misinformation: the official WADA/NADO summary places them on the Monitoring Program, not the Prohibited List.

For contrast, this is unlike growth factors such as MGF and IGF-1 (and their analogues), which are prohibited under WADA Section S2 (peptide hormones, growth factors, related substances and mimetics — banned at all times). VK2735 is not in that category.

Safety

The adverse-event profile is predominantly gastrointestinal, as expected for the incretin class.

In the published subcutaneous VENTURE trial, the most common adverse events were nausea (36.6%, 64/175), constipation (21.1%, 37/175), and vomiting (12.6%, 22/175). Serious treatment-emergent adverse events occurred in 4.6% (8/175), and discontinuation due to an adverse event occurred in 9.1% (16/175).

For the oral Phase 2 trial, the company reported that roughly 98–99% of (GI/drug-related) treatment-emergent adverse events were mild or moderate, with GI events more frequent at higher doses. Higher-dose tolerability is a real consideration. Note: specific per-dose discontinuation figures sometimes circulated for the oral trial (for example, “~13% placebo vs ~38% at 120 mg”) could not be confirmed against a primary source — the verified press releases do not break out discontinuations by dose — so those exact numbers should not be treated as fact.

Most importantly: long-term safety is not established. The 78-week Phase 3 outcomes and any cardiovascular or long-term safety data have not yet read out. Because there is no approved label, there is no validated safety-monitoring framework for off-trial use.

Bottom line

VK2735 has the most encouraging early human data of the current crop of next-generation incretin agonists, anchored by a peer-reviewed Phase 2 subcutaneous trial showing roughly 15% weight loss at 13 weeks. But it remains investigational: Phase 3 is enrolled but unread, the oral data are still company-reported, and long-term safety is genuinely unknown. It is not approved, not a prescription drug, and not a muscle-building compound. Treat it as a promising candidate in active trials — not a proven therapy, and not something with a characterized safety profile for off-trial use.

Evidence grade: Preliminary human.

VK2735 (Viking)