What Is VK2735?

1. How does VK2735 work?

VK2735 activates the two incretin receptors, GLP-1 and GIP, from one peptide. That is the mechanism of tirzepatide, and the what is GIP page covers why adding GIP agonism to GLP-1 agonism appears to raise the ceiling on weight loss at tolerable doses. Viking has not published a structural comparison with tirzepatide; what is public is the receptor profile and the trial results.

Viking Therapeutics is a San Diego-based biopharmaceutical company; VK2735 is its lead metabolic asset and the molecule both formulations share. The injection and the tablet are the same active compound in different delivery systems, run as separate clinical programs rather than one trial with two arms, which is why they have different trial names, different registry numbers, and different stages.

The difference is the delivery bet. Tirzepatide exists only as an injection. Viking is running the same molecule as a weekly injection and as a daily tablet, and the tablet is a peptide, so it faces the absorption problem that forces Rybelsus to use an enhancer and a fasting rule. Viking has not published the tablet’s bioavailability or its administration requirements. The oral vs injectable page explains what is at stake.

2. How much weight do people lose on VK2735?

Two 13-week Phase 2 trials, one per formulation, both in adults with obesity or overweight plus a weight-related condition.

Thirteen weeks is the caveat. Approved drugs are judged at 68 to 72 weeks, and the early slope of a GLP-1 trial is always steeper than the final average. For scale, tirzepatide reached 20.9% at 72 weeks in SURMOUNT-1 and semaglutide 14.9% at 68 weeks in STEP 1; a 13-week number cannot be set beside those. The Phase 3 trials use a 78-week endpoint with a 52-week extension period after that, and the injection results were published in the peer-reviewed journal Obesity in early 2026, more than a year after the 2024 topline release.

The published paper gives the full dose-response for the injection, run between August 2023 and February 2024 in 176 randomized adults (174 in the efficacy analysis: 140 on active drug, 34 on placebo):

These are the final doses of four separate arms; the 5, 10 and 15 mg arms reached them by stepping up over the first weeks, per Viking’s topline release. Ninety-three percent of participants on active drug (130 of 140) lost at least 5% of baseline weight, versus 12% (4 of 34) on placebo. Adverse events were mostly gastrointestinal and dropped in frequency after titration to a steady dose; per-arm discontinuation and nausea/vomiting percentages are given in Section 3.

The oral tablet trial, VENTURE-Oral Dosing (NCT06828055), tested five doses over 13 weeks in 280 adults and gives the clearest look at where the dose-response tops out:

The jump from 15 mg to 30 mg is the largest step in the range, and the curve is still rising at 120 mg rather than flattening, which is why Viking has not called 120 mg a ceiling dose. Viking’s release did not state whether the tablet was dosed fasted or fed, a gap worth flagging given how much fasting and food timing affect oral semaglutide absorption.

3. What are the side effects of VK2735?

Gastrointestinal, at rates in line with the class. Both trials now have published percentages.

The 20% adverse-event discontinuation rate is the number to watch; it is above the 5.3% to 10.3% seen over 72 weeks in ATTAIN-1, the orforglipron trial, though a 13-week trial with fast escalation is not directly comparable. Viking’s release put drug-related adverse events at 98% mild-to-moderate overall and 99% mild-to-moderate among the GI-specific events, and it described the GI events as concentrated early in treatment, tapering with repeated dosing.

For the injection, Viking’s February 27, 2024 VENTURE topline release gives per-arm figures: combined across the four VK2735 dose arms (n=140), nausea occurred in 43% versus 20% on placebo (n=35), and vomiting in 18% (25 of 140) versus none on placebo. Discontinuation was, as Viking described it, “low and well-balanced”: 13% of VK2735 patients (18 of 140) discontinued treatment early versus 14% on placebo, and 4% (5 of 140) discontinued the study early versus 6% on placebo. One VK2735 patient had a serious adverse event of dehydration judged related to study drug. The published Obesity-journal paper reports the same per-arm GI rates (nausea 63% and vomiting 29% at 15 mg) and adds that the dehydration case was in a 5 mg participant who also had atrial fibrillation judged possibly related; one participant on 15 mg died of head trauma from a fall, judged unrelated to the drug. GI events were the most common adverse events and decreased in frequency after titration to steady state. The Phase 3 trials, which run for 78 weeks with a 52-week extension, will produce the longer-duration safety data that matters for a chronic-use drug.

4. What is the VANQUISH program?

Two Phase 3 trials of the injection, each randomized, double-blind, and placebo-controlled, multicenter, with four weekly arms: placebo and 7.5, 12.5, or 17.5 mg. The primary endpoint in both is percent change in body weight from baseline at week 78, followed by a 52-week extension period.

Enrollment finishing is a milestone, not a result. No efficacy data from either trial exist yet, and no regulatory filing has been made. The tablet’s Phase 3 program started later, so a tablet submission is further off than the injection’s.

SUNRISE: the tablet’s Phase 3 program

On October 14, 2026 Viking announced the start of SUNRISE, two randomized, double-blind, placebo-controlled trials of the once-daily tablet. Both compare 27.5, 35 and 55 mg daily with placebo, and the primary endpoint is percent change in body weight at 68 weeks.

ClinicalTrials.gov listed both as not yet recruiting on October 15, 2026. The phase 3 doses are lower than the 90 to 120 mg top doses in VENTURE-Oral, and the registry describes a slower step-up, every 4 weeks starting at 10 mg.

5. How does VK2735 compare with the approved drugs?

The comparison that matters is with tirzepatide, and it does not exist yet; the trials differ in length by a year, and cross-trial comparisons of percent weight loss are unreliable because placebo response, population, and escalation schedule all shift the number. The retatrutide page covers Lilly’s triple agonist and the MariTide page Amgen’s monthly antibody conjugate, the other two late-stage molecules aiming above tirzepatide; between the three, VK2735 is the only one with a tablet in active development. For a log, an investigational drug is entered like any other: product, date, milligrams, and site. How GLP-1 tracking works covers what to record.

6. What happens next?

Both VANQUISH trials are enrolled and running; neither has reported efficacy or safety data. ClinicalTrials.gov lists an estimated primary completion date of July 2027 for both VANQUISH-1 and VANQUISH-2, with study completion estimated a month later; the registry entries do not describe the 52-week extension. A 78-week readout is what would support a filing for the injection; Viking has not given a filing date because it does not have topline results yet.

The tablet’s Phase 3 program, SUNRISE, began in October 2026, as Viking’s July 29, 2026 update had forecast for the fourth quarter. No efficacy or safety data from an oral Phase 3 exist yet.

Maintenance dosing study

Viking’s VK2735-102 maintenance study, in about 180 otherwise healthy adults with obesity, reported topline results on September 22, 2026 (press release only, not peer-reviewed). After 21 weeks of weekly injections stepped up to 15 to 22.5 mg, weight loss was 16.3% to 18.7% versus 0.1% on placebo. Participants were then switched for 12 weeks to less frequent injections or placebo:

Each maintenance arm had only 10 to 16 people, and GI side effects during the maintenance period were similar to placebo. A second part testing a daily oral tablet for maintenance after injectable induction, alongside monthly and every-other-week injections, started on October 6, 2026.

7. VK2735 FAQ

• How much weight do people lose on VK2735?

  In the 13-week Phase 2 trials: up to 14.7% from baseline with the weekly injection (13.1% placebo-adjusted) and up to 12.2% with the daily tablet at 120 mg (10.9% placebo-adjusted). Thirteen weeks is short; approved drugs are judged at 68 to 72 weeks, while the Phase 3 VANQUISH trials will measure 78 weeks.

• Is there a VK2735 pill?

  Yes, in development. The tablet completed the Phase 2 VENTURE-Oral Dosing trial at doses of 15 to 120 mg once daily. It is a peptide, so unlike orforglipron it still faces the absorption problem of oral peptides; Viking has not published its bioavailability. On October 14, 2026 Viking announced the start of the SUNRISE Phase 3 program: two 68-week trials, SUNRISE-1 and SUNRISE-2, each targeting 560 adults, testing 27.5, 35 and 55 mg daily against placebo. ClinicalTrials.gov listed both as not yet recruiting.

• How is VK2735 different from tirzepatide?

  Same two receptors, GIP and GLP-1, both as agonists. Tirzepatide is approved as Mounjaro and Zepbound and exists only as an injection. VK2735 is investigational, and its distinguishing bet is the tablet. No trial has compared the two.

• What are the side effects of VK2735?

  Gastrointestinal. In the tablet trial, nausea occurred in 58% on VK2735 versus 48% on placebo, vomiting in 26% versus 10%, and 20% of VK2735 participants discontinued for adverse events versus 13% on placebo (28% versus 18% for any reason). Viking reports that 98% of drug-related adverse events were mild or moderate. In the injection trial, nausea occurred in 43% on VK2735 (combined doses) versus 20% on placebo, vomiting in 18% versus none, and 13% discontinued treatment early versus 14% on placebo.

• When will VK2735 be approved?

  No filing exists. VANQUISH-1 completed enrollment in November 2025 and VANQUISH-2 in March 2026, both with 78-week primary endpoints; ClinicalTrials.gov lists primary completion for both in July 2027. A filing could follow those readouts; approval would come later.

• Does the VK2735 tablet need to be taken fasted?

  Viking has not said. The VENTURE-Oral Dosing release does not state whether the tablet was taken fasted or with food, unlike oral semaglutide, which requires a fasting rule and a small amount of water because it depends on an absorption enhancer. VK2735 is also a peptide, so it faces the same underlying absorption problem; Viking has not published how it solved it.

• Is VK2735 the same as bentglutide?

  The name circulates online but does not appear in Viking's materials, ClinicalTrials.gov records, or the Obesity journal publication. The reliable identifier is VK2735.

8. Sources