Petrelintide
Phase 3 trials began in 2026.
A weekly injection pitched on tolerability. It caused less weight loss than the drugs in , with almost no extra dropouts. A made by Zealand Pharma and Roche, also called ZP8396.
What the evidence shows
Side effects and risks
Who should avoid it: Anyone outside a clinical trial.
How it works
- Where it acts
- Amylin receptors.
- What it changes
- Stronger fullness signals and a slower-emptying stomach.
- What people notice
- In phase 2, less weight loss than GLP-1 drugs, with few people stopping because of side effects.
How it has been given in trials
Weekly injection under the skin. There is no approved dose.
Getting it in the United States
The legal route for Petrelintide
Not approved. The only lawful way to get it is to join a clinical trial.
Routes people use for any peptide in the United States
Telehealth prescribing
Online clinics prescribe after a questionnaire, sometimes with no live doctor visit, and mail the drug. FDA moved in February 2026 to restrict mass-marketed compounded copies and claims that they are generic equivalents.
Risk: Thin medical screening. Compounded versions are not reviewed by FDA for quality.
Covers: Approved GLP-1 drugs, compounded semaglutide and tirzepatide
Source: GZERO Media, Apr 2026
Clinical trial enrolment
The only lawful way to get an unapproved peptide drug with medical monitoring. ClinicalTrials.gov lists eligibility, sites and phone numbers. Researchers note recruitment is hard when people can buy the drug on the gray market instead of risking placebo.
Risk: Possible placebo assignment, strict eligibility and travel to a study site.
Covers: Investigational peptide drugs still in development
Source: NIH, finding a clinical trial
Routes people use for any peptide in the United States
Compounding pharmacy with prescription
A clinician prescribes and a pharmacy compounds. Twelve peptides left the FDA do-not-compound category in April 2026 and a panel backed six in July, but they are not yet formally eligible. Pharmaceutical-grade ingredient is scarce.
Risk: Legal status is unsettled until FDA rulemaking ends. Pharmacies may use research-grade ingredient.
Covers: BPC-157, TB-500, KPV, MOTS-c, Semax, Epitalon and similar
Source: Frier Levitt, Apr 2026
Med spas and weight-loss clinics
Very common. Secret shoppers called 75 clinics and med spas in two states after shortages ended. 92 percent offered compounded semaglutide and 87 percent tirzepatide, often mixed with B vitamins to look custom.
Risk: Four of 23 suppliers lacked sterile compounding licenses and four had disciplinary records.
Covers: Compounded semaglutide and tirzepatide
Source: American Med Spa Association on JAMA Health Forum study, Jul 2026
Concierge and longevity doctors
Cash-pay physicians build peptide plans for wealthy clients. Reporting from San Francisco says some source from overseas channels, domestic research-use-only sellers or the few compounding pharmacies that will supply clinicians.
Risk: A doctor's involvement does not guarantee a pharmaceutical-grade product.
Covers: BPC-157, thymosin alpha-1, Selank, Semax, CJC-1295, ipamorelin, retatrutide
Source: San Francisco Standard, Sep 2025
Cross-border purchase or import
FDA says importing drugs for personal use is illegal in most cases but it may not object to small personal quantities in limited situations. Reporting also describes people travelling to Mexico for injections.
Risk: Packages can be seized. Product origin and cold-chain handling are hard to check.
Covers: Approved prescription peptides sold abroad
Source: FDA, personal importation
Routes people use for any peptide in the United States
Research-chemical websites
Sites sell vials marked for research or not for human consumption, with no prescription. FDA says some ship direct to consumers with dosing directions, and it has sent warning letters. Retatrutide exists only through this route or trials.
Risk: Unknown identity, strength and sterility. No pharmacist or prescriber involved.
Covers: Retatrutide, semaglutide, tirzepatide, BPC-157 and most unapproved peptides
Source: FDA, unapproved GLP-1 drugs page
Direct orders from Chinese factories
Buyers message factory sales agents and pay by crypto or payment app. A minimum order of about ten vials pushes people to buy in bulk and share. A blockchain analysis found US buyers were the largest source of funds.
Risk: Many of the same vendors list fentanyl precursors. Lab reports sent by sellers cannot be verified.
Covers: GLP-1 copies, melanotan II, BPC-157, TB-500, GHK-Cu, epitalon
Source: TRM Labs, Oct 2026
Chat groups and social sellers
Dealers are found through Telegram, WhatsApp, Discord and influencer discount codes. In a May 2026 survey of 1,000 US users, 14.5 percent bought this way and three quarters asked an AI chatbot for dosing.
Risk: 45 percent of social media buyers in that survey reported an emergency or urgent care visit for a reaction.
Covers: Retatrutide and other research-use-only peptides
Source: The Ethos, May 2026
This describes what people do. It is not advice. The decision is yours.
More contextCase reports, what public figures say, videos and articles and when options run out
Case reports
From journals, regulators and studies of users. One case proves little.
Benefit reportedtrial result in rare group - 220 people - 2026
Phase 2 trial in adults with type 2 diabetes and excess weight. Weight fell up to about 9 percent at 28 weeks against 2 percent on placebo. Blood sugar improved. Few stopped for gut side effects. Company-reported topline data.
Source: Zealand Pharma release, 2026-10
What experts and influencers say
Paraphrased from the linked sources.
Said the modest size of the weight loss will probably shrink the drug's real-world role in a crowded obesity market. His firm downgraded Zealand shares.
Source: Clinical Trials Arena, 2026-03
Andy HsiehWebsiteWarns against
Photo source: qb3.berkeley.edu
Said the phase 2 tolerability beat company expectations and that, with double-digit weight loss, the drug could change how weight is managed.
Source: Fierce Biotech, 2026-03
Adam SteensbergWebsiteRecommends
Money: Zealand Pharma executive
Photo source: lex.dk
Said the data support a well-tolerated amylin backbone for future combinations, but that the drug is unlikely to lead as a stand-alone treatment soon.
Source: Clinical Trials Arena, 2026-03
Argued that tolerability is the top unmet need in obesity drugs and that gentler weight loss could suit some patients, including first-time users. Roche is also studying a combination.
Source: Fierce Biotech, 2026-06
Manu ChakravarthyWebsiteRecommends
Money: Roche executive
Photo source: bioworld.com
Said amylin analogues may preserve muscle better than GLP-1 drugs, which could answer worries about muscle loss.
Source: Clinical Trials Arena, 2026-03
Edit KovalcsikSourceRecommends
Said the phase 2 results in people with type 2 diabetes confirm meaningful weight loss and showed encouraging blood sugar improvement.
Source: Zealand Pharma release, 2026-10
David KendallSourceRecommends
Money: Zealand Pharma executive
Watch and read
Explainers, reporting and podcasts worth your time. Summaries are ours. No sellers.
Inside the deal: Roche and Zealand Pharma's $5.3 billion obesity drug gambit
Karen Gilchrist, CNBC reporter
Explains petrelintide as an amylin-based obesity drug and why Roche backed it, citing early hints of GLP-1-like weight loss with better tolerability.
Best plain-English introduction to what petrelintide is
ADA: Tolerability 'not to be underappreciated' in Roche, Zealand's amylin obesity prospect
Fraiser Kansteiner, reporter
Reviews phase 2 ZUPREME-1 data: up to 10.7% weight loss at 42 weeks with mild side effects, trailing incretin drugs such as Wegovy.
Shows how it compares with Wegovy and Zepbound
Zealand, Roche's 'intriguing' weight loss for amylin drug soured by blood sugar data
Nick Paul Taylor, reporter
Reports phase 2 ZUPREME-2 results in type 2 diabetes: notable weight loss but weaker blood sugar lowering than rivals, so tolerability may suit maintenance.
Latest data, including where it falls short
When options run out
Uses people turn to when standard treatment has failed.
Gentler option for side-effect-averse patients
- Who
- People who want moderate weight loss and fear or have had gut side effects on GLP-1 drugs.
- Evidence
- Phase 2 trial of 493 people: about 11 percent weight loss at 42 weeks, vomiting no higher than placebo. Investors judged the weight loss disappointing.
- Route
- ZUPREME phase 3 programme
Source: European Biotechnology, 2026-03
Obesity with established cardiovascular disease
- Who
- People with excess weight and existing heart or vessel disease.
- Evidence
- No results yet. One of three phase 3 trials is dedicated to this group.
- Route
- ZUPREME-5 trial
Source: Zealand Pharma release, 2026-10
Legal last-resort routes
Expanded access (compassionate use)
For a serious or life-threatening condition with no comparable alternative and no trial you can join. Your physician asks the company for the drug, then files with FDA and an ethics board. The company can refuse. Costs are often not insured.
Right to Try
For a life-threatening condition after approved options are exhausted and no trial is open to you. The drug must have finished Phase 1 and be in active development. Your doctor asks the manufacturer directly. FDA does not review requests.
Source: FDA, Right to Try
Trial finders
Search ClinicalTrials.gov by condition or drug name, check eligibility and call the listed site. ResearchMatch is a free NIH-funded registry that lets researchers find you. Discuss risks with your own clinician before enrolling.
Source: NIH, finding a clinical trial
Personal import for serious conditions
FDA may not object when a US citizen imports up to about three months of a drug for a serious condition with no effective US treatment, with written personal-use confirmation and a US doctor's details. It is discretion, not a right.
Source: FDA, personal importation
Patient-specific compounding
When the approved product cannot meet a specific need of an identified patient, a prescriber can order a compounded version from a licensed pharmacy. Lower price alone does not qualify. Ingredients must be pharmaceutical grade.
Questions people ask
How much weight loss did petrelintide give?
In ZUPREME-1 (493 people), loss reached up to 10.7% at 42 weeks, against 1.7% on placebo. That is less than the GLP-1 drugs achieved in phase 2.
Is petrelintide easier to tolerate than GLP-1 drugs?
It is pitched on tolerability. In the most effective dose group of the phase 2 trial, 4.8% stopped because of side effects, against 4.9% on placebo.
Is petrelintide approved?
No. Three phase 3 trials with about 7,000 people began in 2026, and there is no approved dose.
Who makes petrelintide?
Zealand Pharma and Roche develop it together.
Your notebook
Taking it? A ten-second daily check-in keeps a record of how you feel, to talk through with your clinician.
Sources
Structure: PubChem