Final VK2735 Phase 2 injection results published in Obesity

Viking Therapeutics has published the final results of its Phase 2 VENTURE trial for VK2735, an injectable obesity drug, in the journal Obesity, the publication of The Obesity Society ^[1][2]. The trial found average weight loss of up to 14.7% from baseline after just 13 weekly doses, with no plateau in the weight-loss curve ^[2].

VK2735 is a dual agonist that acts on both the GLP-1 and GIP receptors, similar in mechanism to tirzepatide, the molecule in Mounjaro and Zepbound ^[2]. The company first reported these top-line numbers at the ObesityWeek conference in November 2025, and the January 2026 publication represents the peer-reviewed version of that data ^[2].

Alongside the efficacy findings, Viking reported that VK2735 was "safe and well tolerated" through the 13 weeks of dosing, with most treatment-related side effects described as mild or moderate and resolving quickly ^[2]. The company has not published a specific breakdown of which side effects occurred or at what rates in the sources reviewed here; that detail is not yet available in the materials cited.

The published Phase 2 results are the same data set Viking used to move VK2735 into Phase 3 testing. Following the trial and meetings with the Food and Drug Administration, Viking launched the VANQUISH Phase 3 program in June 2025, consisting of two studies: one in adults with obesity and one in adults with both obesity and type 2 diabetes ^[2]. Each trial tests once-weekly subcutaneous injections at 7.5 mg, 12.5 mg, or 17.5 mg against placebo over 78 weeks ^[2]. The VANQUISH-1 study enrolled roughly 4,500 participants by November 2025, about five months after starting, and the smaller VANQUISH-2 study finished enrolling around 1,000 participants in early 2026 ^[2]. As of the company's July 2026 update, both studies were fully enrolled and continuing as planned ^[2].

Why it matters for patients

The VENTURE trial was a mid-stage, 13-week study, not the final word on how well VK2735 works or how safe it is over the longer term. The Phase 3 VANQUISH trials will track participants for 78 weeks and are designed to measure the actual difference in weight loss between the drug and placebo, along with what share of patients reach 5%, 10%, 15%, or 20% weight loss ^[2]. Those results, not the Phase 2 numbers, will determine whether VK2735 can be submitted for FDA approval.

For people currently weighing GLP-1 or dual-agonist options like Wegovy, Zepbound, or Mounjaro, VK2735 is not an approved or currently available treatment. It remains an investigational drug still years from a possible market launch, and the 14.7% figure describes an average from a small, short trial rather than a guarantee for any individual ^[2].

Viking is also developing an oral tablet version of VK2735. In its own Phase 2 study, the tablet produced weight loss up to 12.2% after 13 weeks, with up to 80% of treated participants losing at least 10% of their body weight, compared with 5% of those on placebo ^[2]. If both the injectable and oral versions eventually reach the market, Viking says patients could potentially switch between formulations of the same drug rather than switching between different active ingredients, which the company argues could reduce the risk of new or unexpected side effects ^[2]. That claim comes from the company itself and has not yet been tested against real-world switching data.

What happens next

Viking expects results from a separate maintenance-dosing study, which is testing monthly and every-other-week injection schedules, in the third quarter of 2026 ^[2]. The company also plans to start a Phase 3 trial of the oral tablet formulation in the fourth quarter of 2026 ^[2]. The VANQUISH-1 and VANQUISH-2 trials themselves are 78-week studies and are not expected to report primary results within that timeframe based on current enrollment dates ^[2].