An experimental Viking Therapeutics obesity drug that hits the same targets as a commercialized Eli Lilly medication has clinical data showing it led to an average 13.1% weight loss after 13 weeks of treatment, results that indicate it could compete favorably with the pharmaceutical giant’s product and others on the market.
There was no plateau to the weight loss in the mid-stage study, suggesting that patients could lose even more weight with more time, Viking said Tuesday. The San Diego-based biotech plans to meet with the FDA to discuss the next steps for the drug, VK2735. Investors welcomed the news as shares of the biotech opened Tuesday at $69.77 apiece, up more than 81% from Monday’s closing price.
VK2735 is part of a growing class of drugs that work by mimicking hormones in the gut to spark a range of metabolic effects. Novo Nordisk’s Wegovy targets and activates the GLP-1 receptor. The Viking drug is an agonist of both the GLP-1 and GIP receptors. The preliminary results reported Tuesday are from a placebo-controlled Phase 2 clinical trial that tested four doses of the Viking drug, administered as a once-weekly injection. The study enrolled 176 adults who are obese or overweight with at least one weight-related co-existing condition. The main goal was to measure the percent change in body weight after 13 weeks.
Viking said the statistically significant weight loss was observed for all doses starting at week one and continuing throughout the course of the 13-week study. Furthermore, up to 88% of participants in the treatment groups achieved 10% or greater weight loss compared with just 4% of those in the placebo arm.
The Viking drug was safe and well tolerated. Most of the treatment-related adverse effects were gastrointestinal, which is consistent with these types of drugs. Viking said most of those effects were classified as mild or moderate, though one patient experienced a severe adverse event of dehydration characterized as related to the study drug. Of the 23 patients who discontinued treatment, 18 were in the treatment groups and five were from the placebo arm.
Acknowledging all of the caveats of cross-trial comparisons, William Blair analyst Andy Hsieh said in a research note that the magnitude of placebo-adjusted weight loss at VK2735’s highest dose offers best-in-class potential compared to approved and investigational drugs with Phase 2 data. William Blair’s previous position was that the Viking drug could be clinically equivalent to Lilly’s tirzepatide, marketed as Zepbound for weight management. Now the firm believes VK2745 could offer better efficacy. That potential would be best realized at a large pharmaceutical company.
“Ultimately, we believe that the value of VK2735 will be maximized in the hands of a big pharma, which could best navigate the rebate/discount-driven reimbursement landscape,” Hsieh said.
Leerink Partners analyst Thomas Smith said in a research note that the 13.1% weight loss achieved with VK2735 compares favorably with competing drugs that activate the GLP-1 and GIP receptors, including Lilly’s Zepbound. That drug led to less than 10% absolute weight loss at all doses at the 13-week mark of its Phase 3 clinical trial. Viking’s drug will still need to show its results can be replicated in a larger a Phase 3 test. However, the greater than 13% placebo-adjusted weight reduction from VK2735 in Phase 2 exceeds the bar for success set by both Viking management and investors, Smith said.
Viking CEO Brian Lian said in a prepared statement that the company plans to advance VK2735 further into clinical development later this year. The company is also developing an oral formulation of the obesity drug. A Phase 1 test of oral VK2735 is on track to report data later this quarter, Lian said.
Photo: Peter Dazeley, Getty Images
