How does petrelintide compare to cagrilintide?

Both are amylin agonists, but with different receptor profiles and clinical positioning. Cagrilintide is typically used in combination with semaglutide (CagriSema — 20.4% weight loss at 68 weeks). Petrelintide as monotherapy achieves 10.7% at 42 weeks but with notably better tolerability. Its planned Roche-driven combination with CT-388 (dual GLP-1/GIP) could produce similar or greater combined weight loss than CagriSema, with petrelintide's tolerability advantage.

How does petrelintide differ from eloralintide?

Eloralintide (Lilly) is a selective AMY1 receptor agonist (12x selectivity over CTR). Petrelintide (Zealand/Roche) is a balanced dual AMYR + CTR agonist. Eloralintide's Phase 2 showed higher peak weight loss (20.1% at 9 mg over 48 weeks) but at the cost of more GI side effects at top doses. Petrelintide trades peak magnitude for placebo-like tolerability.

When will petrelintide be available?

Phase 3 monotherapy trials are expected to start in H2 2026 (triggering a $575M milestone payment to Zealand from Roche). FDA approval is realistically 2029-2030. It is not currently available outside clinical trials.

Petrelintide

Zealand Pharma's long-acting amylin analog, partnered with Roche in a $5.3B deal. Phase 2b ZUPREME-1 showed 10.7% weight loss at 42 weeks with placebo-like tolerability — the 'tolerability play' in the amylin class.

ModerateLimited Data

What is Petrelintide?

Petrelintide (ZP8396) is a long-acting, acylated human amylin analog developed by Zealand Pharma and partnered with Roche in a March 2025 deal worth up to $5.3 billion — the largest single-asset pharma partnership of 2025. It is a 36-amino-acid dual agonist at the amylin receptor (AMYR) and calcitonin receptor (CTR), engineered for neutral-pH stability to enable once-weekly dosing and co-formulation with other peptides. In Phase 2b ZUPREME-1 (493 patients, 42 weeks, topline March 2026), petrelintide produced up to 10.7% weight loss vs 1.7% placebo — while achieving placebo-like GI tolerability (single-digit diarrhea/constipation rates, minimal nausea after maintenance dose). Lower trial withdrawal on drug (8.4%) than placebo (13.6%) suggests patients can actually stay on it long-term. The combination to watch: petrelintide + CT-388 (Roche's dual GLP-1/GIP) enters Phase 2 in H1 2026.

Why People Talk About It

Weight loss with placebo-like tolerability

Moderate

Alternative for patients who can't tolerate GLP-1 side effects

Moderate

Lean mass preservation (preclinical)

Preliminary

Combination with CT-388 for enhanced effect

Limited

Leptin sensitivity restoration

Preliminary

How It Works

Amylin is a natural hormone your pancreas releases with insulin after meals — it tells your brain you're full. Petrelintide mimics amylin but lasts much longer, enabling weekly dosing. Unlike GLP-1 drugs, it works through a completely different pathway (amylin/calcitonin receptors instead of GLP-1 receptors), which is why it has a very different side effect profile — much less nausea, especially after the first few weeks.

Common Questions

Safety Information

Important Safety Notes

Common Side Effects

Mild nausea (mostly during dose escalation, resolves after reaching maintenance)Diarrhea and constipation rates similar to placebo (single-digit)Mild transient injection site reactions

Cautions

• Not FDA-approved — investigational drug in Phase 2b/3
• Limited long-term safety data beyond 42 weeks
• Not available outside clinical trials

What We Don't Know

Cardiovascular outcomes data not yet available. Long-term safety and durability beyond 42 weeks are not established. Real-world performance vs. controlled trial conditions is untested. Long-term effects on pancreatic function and CTR-mediated bone metabolism require further study.

Published Research

9 studies

Development of Petrelintide: a Potent, Stable, Long-Acting Human Amylin Analogue.

PreclinicalPMID: 41217931

Eloralintide, a novel amylin receptor agonist for the treatment of obesity: From discovery to clinical proof of concept.

PreclinicalPMID: 41109426

A Review of Amylin Peptide Receptor Activators for Obesity Pharmacotherapy.

ReviewPMID: 40910290

Cagrilintide-Semaglutide in Adults with Overweight or Obesity and Type 2 Diabetes (REDEFINE 2).

Randomized Controlled TrialPMID: 40544432

Amylin takes another shot at the obesity prize.

News CommentaryPMID: 40394341

Amylin: emergent therapeutic opportunities in overweight, obesity and diabetes mellitus.

ReviewPMID: 40360789

Amylin: From Mode of Action to Future Clinical Potential in Diabetes and Obesity.

ReviewPMID: 40332747

Amylin as a Future Obesity Treatment.

ReviewPMID: 34929674

Amylin - Its role in the homeostatic and hedonic control of eating.

ReviewPMID: 29203236

Mechanism of Action

Petrelintide is a 36-amino-acid acylated human amylin analog engineered for chemical stability at neutral pH (avoiding the amyloid fibrillation problems of native amylin/pramlintide). It acts as a balanced potent agonist at both the amylin receptor (AMYR, a CTR/RAMP heterodimer) and the calcitonin receptor (CTR). Activation in hindbrain structures (area postrema, nucleus tractus solitarius) promotes satiety, restores leptin sensitivity, delays gastric emptying, suppresses postprandial glucagon, and increases energy expenditure. Half-life ~33.8 hours supports once-weekly dosing. Phase 2b ZUPREME-1 (493 patients, 42 weeks): up to 10.7% weight loss at 9 mg vs 1.7% placebo, with all 5 dose arms meeting primary endpoint vs placebo at week 28. Key differentiator: GI tolerability — diarrhea/constipation rates similar to placebo; nausea mostly mild and largely resolved after reaching maintenance dose; 98% of top-cohort participants reached maintenance dose. Trial withdrawal rate: 8.4% petrelintide vs 13.6% placebo.

Evidence Snapshot

Overall Confidence55%

Human Clinical Evidence

Moderate and growing. Phase 2b ZUPREME-1 (NCT06662539, 493 patients, 42 weeks, 2026) topline: 10.7% weight loss vs 1.7% placebo, exceptional tolerability. Phase 1b MAD Part 2 (48 patients, 16 weeks): dose-dependent weight loss 4.8-8.6%. Phase 1 SAD (56 patients): up to 4.2% weight loss at 1 week sustained 6 weeks. Phase 2b ZUPREME-2 in T2DM patients (NCT06926842) with topline expected H2 2026.

Animal / Preclinical

Supportive. In DIO rats, petrelintide produced preferential fat-mass loss and preserved relative lean mass vs liraglutide comparator — potential differentiator from GLP-1 class. Published discovery and optimization chemistry (J Med Chem 2025, PMID: 41217931).

Mechanistic Rationale

Strong. Amylin biology is well-established (decades of pramlintide research). Petrelintide's innovation is chemical stability at neutral pH (enabling combination with other peptides like CT-388) and extended half-life for weekly dosing. Balanced AMYR/CTR agonism has clear physiologic basis for satiety and metabolic effects.

Forms & Administration

Petrelintide is administered as a once-weekly subcutaneous injection. Phase 2 tested maintenance doses from 2.4 mg to 9 mg with 4-week dose escalation. Slower escalation improved tolerability significantly vs earlier Phase 1b protocols. Currently only available through clinical trials.

Use Cases & Evidence Levels

Weight loss with placebo-like tolerability

Moderate70%

Alternative for patients who can't tolerate GLP-1 side effects

Moderate70%

Lean mass preservation (preclinical)

Preliminary30%

Combination with CT-388 for enhanced effect

Limited15%

Leptin sensitivity restoration

Preliminary30%

Safety Profile

Safety Information

Common Side Effects

Mild nausea (mostly during dose escalation, resolves after reaching maintenance)Diarrhea and constipation rates similar to placebo (single-digit)Mild transient injection site reactions

Cautions

• Not FDA-approved — investigational drug in Phase 2b/3
• Limited long-term safety data beyond 42 weeks
• Not available outside clinical trials

What We Don't Know

Published Research

9 studies

Development of Petrelintide: a Potent, Stable, Long-Acting Human Amylin Analogue.

PreclinicalPMID: 41217931

Eloralintide, a novel amylin receptor agonist for the treatment of obesity: From discovery to clinical proof of concept.

PreclinicalPMID: 41109426

A Review of Amylin Peptide Receptor Activators for Obesity Pharmacotherapy.

ReviewPMID: 40910290

Cagrilintide-Semaglutide in Adults with Overweight or Obesity and Type 2 Diabetes (REDEFINE 2).

Randomized Controlled TrialPMID: 40544432

Amylin takes another shot at the obesity prize.

News CommentaryPMID: 40394341

Amylin: emergent therapeutic opportunities in overweight, obesity and diabetes mellitus.

ReviewPMID: 40360789

Amylin: From Mode of Action to Future Clinical Potential in Diabetes and Obesity.

ReviewPMID: 40332747

Amylin as a Future Obesity Treatment.

ReviewPMID: 34929674

Amylin - Its role in the homeostatic and hedonic control of eating.

ReviewPMID: 29203236

Related Peptides

Eloralintide

Emerging

Eli Lilly's once-weekly selective amylin receptor agonist. Phase 2 trials showed up to 20% weight loss at 48 weeks with favorable tolerability. Phase 3 enrollment began late 2025.

Cagrilintide

Emerging

A long-acting amylin analogue being developed in combination with semaglutide (CagriSema) for enhanced weight loss.

Pramlintide

Strong

An FDA-approved synthetic analogue of amylin used alongside insulin for diabetes, also studied for weight management.

Semaglutide

StrongBeginner

A GLP-1 receptor agonist FDA-approved for type 2 diabetes and chronic weight management, one of the most widely prescribed peptide drugs.

Tirzepatide

StrongBeginner

A dual GIP/GLP-1 receptor agonist FDA-approved for diabetes and weight management, producing the largest weight loss seen in clinical trials.

CT-388

Moderate

Roche/Genentech's next-generation dual GLP-1/GIP receptor agonist. Phase 2 showed 22.5% placebo-adjusted weight loss at 48 weeks — competitive with retatrutide. Phase 3 ENITH program starts Q1 2026.

Quick Facts

Class: Amylin Receptor Agonist
Evidence: Moderate
Safety: Limited Data
Updated: Apr 2026
Citations: 9PubMed

Also known as

ZP8396

Evidence Score

Overall Confidence55%

Clinical Trials

View Clinical Trials

Links to ClinicalTrials.gov for reference. Listing does not imply endorsement.