Viking Therapeutics Shares Surge After Obesity Shot Shows Up to 22% Weight Loss in Small Study

Viking Therapeutics Inc. shares jumped 24% in premarket trading on September 22, 2026, after its dual-action obesity drug helped patients lose up to 22% of body weight in a small exploratory study, even after patients reduced their dosing frequency. The 11 patients receiving an intermediate weekly dose lost 19% of body weight after about five months, while 13 patients on a slightly lower dose for an additional three months lost 22% with no plateau, the company said. Those who transitioned to once- or twice-monthly dosing maintained 90% to 97% of the weight loss. Side effects were mostly mild, with only one patient discontinuing treatment. The results underscore investor interest in alternatives to weight-loss drugs currently dominated by Eli Lilly & Co. and Novo Nordisk A/S. Viking's therapy targets both GLP-1 and GIP receptors and is being developed as injections and pills.