Dive Brief:
- Trial enrollees taking Viking Therapeutics’ dual-acting obesity drug maintained nearly all of their weight loss after switching from a weekly shot to less frequent dosing, the company said Tuesday.
- Viking enrolled 180 people with obesity and no related health conditions in the Phase 2 trial. They were randomized to receive one of four dosing regimens of VK2735 or a placebo over 21 weeks, and then switched to a biweekly or once-monthly maintenance shot for another 12 weeks. According to Viking, enrollees taking VK2735 ended up retaining as much as 90% of their weight loss.
- The “stellar” data “build on [VK2735’s] potentially differentiated profile,” Leerink Research analyst Thomas Smith wrote in a note to clients, potentially allowing the drug to overcome some of the adherence issues associated with GLP-1 medications for obesity. Viking shares rose as much as 36% in morning trading.
Dive Insight:
GLP-1 drugs like Novo’s Wegovy and Eli Lilly’s Zepbound have reshaped how physicians treat obesity, enabling patients to achieve double-digit weight loss with the help of a weekly shot or daily pill.
But drugmakers have yet to address some of their limitations, like gastrointestinal side effects or the need to stay on treatment chronically to keep weight down. Lagging adherence rates are one indicator of these problems.
Viking’s Phase 2 trial is an example of an alternate treatment strategy. The company tested VK2735 — which, like Zepbound, modulates the metabolic hormones GLP-1 and GIP — in an “induction” phase that gradually moved enrollees up to weekly doses of 15, 17.5, 20 or 22.5 milligrams. After 21 weeks, weight loss ranged from 16% in the 15 mg group to 19% in the 20 mg group.
After that phase, some enrollees were transitioned to biweekly or monthly injections for another 12 weeks. Among those participants, average weight loss maintenance ranged from 82% to 97%, depending on the dosing strategy.
In the larger group of all enrollees moved to every-other-week dosing, average weight loss maintenance was 90%. For the monthly dosing group, that figure was 85%, Viking said.
“These results are important as they provide a basis for improved dosing flexibility for both clinicians and their patients," said Louis Aronne, the former president of The Obesity Society and a professor of metabolic research at Weill-Cornell Medical College, in a statement provided by Viking. “Flexibility for patients and providers is paramount for achieving treatment persistence leading to the long-term benefits of weight control and these results are an important step in that direction.”
Viking reported low rates of discontinuations related to side effects. One occurred during the induction phase, another was in the every-other-week dosing group and three more were in the monthly dosing cohort. The frequency of gastrointestinal side effects wasn’t “meaningfully different” during the maintenance phase, Viking said.
VK2735’s Phase 3 clinical trials were fully enrolled as of November 2025 and testing doses only up to 17.5 mg weekly.
