Zealand Pharma and Roche plan Phase 3 program for petrelintide in weight management

On April 29, 2026, Zealand Pharma and Roche said they will advance petrelintide, an investigational once-weekly amylin analog, into Phase 3 trials for chronic weight management. The companies plan to start the program in the second half of 2026 ^[1].

Petrelintide is being developed as a once-weekly subcutaneous injection for adults living with obesity or with overweight plus weight-related health conditions ^[1]. In the Phase 2 ZUPREME-1 trial (NCT06662539), people taking the drug lost up to 10.7% of their body weight on average at 42 weeks, compared with 1.7% for those taking placebo, meeting the study's primary goal ^[2]. Roche reported that gastrointestinal side effects occurred at low rates and that no participants stopped treatment because of vomiting at the highest doses, a profile the sponsors described as "placebo-like" ^[2].

An earlier Phase 1b study that tested rising doses found reductions in body weight and waist circumference that increased with dose. Women in that study appeared to respond more strongly, while tolerability stayed favorable ^[2].

Analysts quoted by BioPharm International noted that petrelintide's weight loss looks somewhat lower than that of leading GLP-1-based therapies, and pointed to tolerability and long-term adherence as areas where petrelintide could stand apart ^[2].

Petrelintide copies the hormone amylin, which is made in the pancreas and released along with insulin after eating. Activating amylin receptors has been shown to lower body weight by restoring sensitivity to the satiety hormone leptin and by creating a faster sense of fullness ^[1].

The two companies entered a collaboration and license agreement in March 2025 to co-develop and co-commercialize petrelintide. BioPharm International reported the deal as worth up to $5.3 billion, with Roche paying $1.65 billion upfront ^[2]. Adam Steensberg, president and chief executive officer of Zealand Pharma, said the move to Phase 3 "marks an important step for the program and our collaboration with Roche" ^[1].

Why it matters for patients

Petrelintide is not approved by the US Food and Drug Administration, and no regulatory decision date has been disclosed ^[1][2]. Anyone currently weighing treatment options cannot get petrelintide outside a clinical trial, and whether Phase 3 will enroll participants and where has not been reported ^[1][2].

The drug is also a weekly injection rather than a pill, so it would not add an oral option to the market ^[1]. Its main proposed selling point is tolerability. Zealand and Roche argue that a treatment people can stay on without disrupting daily life matters in a chronic condition, and BioPharm International frames the drug as a possible choice for patients who cannot tolerate or do not respond well enough to current therapies ^[1][2]. Those are goals, not established results: the Phase 2 findings come from a single mid-stage trial, and whether they hold up in larger, longer Phase 3 studies is the open question ^[2].

Many practical details remain unknown, including price, insurance coverage and how petrelintide would compare with existing medications in a head-to-head study. None of that has been disclosed ^[1][2]. Whether the full ZUPREME-1 results have been published in a peer-reviewed journal has not been reported ^[2].

What happens next

The Phase 3 program in chronic weight management is planned to begin in the second half of 2026 ^[1]. A separate Phase 2 trial testing petrelintide in combination with Roche's GLP-1/GIP dual agonist enicepatide (CT-388) is planned to start in the second quarter of 2026 ^[1]. The number of Phase 3 trials, how many people they will enroll, how long they will run, and when results or a regulatory filing might be expected have not been disclosed ^[1][2].