Policy Tracker · Patient Lens · October 4, 2026
Two drug makers test what happens after semaglutide stops working for you
One trial checks a brand new injection in people who never tried a GLP-1, the other checks if switching drugs is even safe.
Key details
- A Novo Nordisk phase 1 trial starting fall 2026 will test whether switching from semaglutide to zenagamtide is safe for 60 people.
- Boehringer Ingelheim will enroll 350 people without diabetes starting November 2026 to test survodutide, a new weight-loss injection.
Two new trials, tracked on October 3, 2026, look at what comes after semaglutide. One asks whether people already on the drug can switch to something newer without problems. The other tests a different injection in people who have never used a GLP-1 drug at all. If you take semaglutide now or are considering a GLP-1 for weight loss, both studies could shape what options you have later.
Novo Nordisk's phase 1 trial, set to begin in fall 2026, will enroll 60 adults with overweight or obesity, with or without type 2 diabetes, who are currently taking semaglutide. The study asks a narrow but practical question: can these patients move to zenagamtide, a newer GLP-1 drug, safely? This matters because many people on semaglutide eventually look for an alternative, and right now there is little formal data on what switching does to tolerability or side effects. A phase 1 study of this size will not settle the question on its own. It should offer early signals on whether a planned transition between these two drugs is reasonable to study further in larger trials.
Boehringer Ingelheim's trial, called SYNCHRONIZE-START, takes a different approach. Starting in November 2026, the company will enroll 350 people with overweight or obesity who do not have diabetes, none of whom have used a GLP-1 drug before. This is a phase 3 study, meaning survodutide has already moved past early safety testing and is now being evaluated at a scale closer to what the FDA would need for approval. Because participants are GLP-1 naive, the trial should show how the drug performs on its own, without the influence of prior GLP-1 use. That makes it a more direct test of survodutide's effect on weight than a switch study could offer.
These two trials are tracking different questions, and the answers will not arrive at the same time or in the same way. If you are on semaglutide and wondering about switching, the Novo trial is the one to watch, though phase 1 data takes time to mature. If you have not yet started a GLP-1 drug, the Boehringer trial may eventually tell you more about survodutide's standalone effect. In either case, I would suggest waiting for published results before changing your treatment plan, and talking with your prescriber about what these trials could mean for you.
By Amanda Bonello