Evidence review: Open Peptide Project (verified against primary PubMed, ClinicalTrials.gov & FDA records) · Last checked 2026-10-27. ← Back to Evidence Library

Pegozafermin: what the evidence says

Name: Pegozafermin
Published: 2026-10-27

At a glance

What it is: a long-acting, glyco-PEGylated version of the hormone FGF21, injected weekly or every 2 weeks. ^R1 Developed by 89bio; Roche is now listed as lead sponsor of the phase 3 trials. ^{R2, R3}

What the evidence says: in a 24-week phase 2b trial (ENLIVEN), more people had fibrosis improvement than on placebo. ^{R1, R4} In an 8-week phase 2 trial in severe high triglycerides, levels fell 57% vs 12% on placebo. ^{R5, R6}

Biggest risks: nausea and diarrhea were most common. ^R1 Long-term safety is unknown.

Rating


Human Human evidence	Moderate: 2 placebo-controlled phase 2 trials ^{R1, R5}; earlier phase 1b/2a ^R7
Animal Animal / lab evidence	Not reviewed here
Regulatory	Investigational, not FDA-approved · not on FDA's 503A or 503B bulk-substance category lists and not on FDA's compounding safety-risk page · WADA S2.3 covers FGFs by class UNVERIFIED whether this analogue is captured ^{R8, R9, R10, R11}
Established human dose	None approved. Study details lists what trials used

Evidence verdict: MASH fibrosis: Moderate (phase 2b RCT) · Severe high triglycerides: Moderate (phase 2 RCT; phase 3 done, results not yet posted) · Weight loss, longevity: No human data

This page reports what studies used. It is not dosing advice.

Legend: HUMAN data · ANIMAL / LAB data · UNKNOWN · UNVERIFIED: not yet confirmed against a primary source

About the evidence: the trials used biopsy and lipid endpoints over 8 to 24 weeks. Phase 3 outcome results are not yet published. ^{R12, R2, R3}

What is it?

FGF21 is a liver hormone that affects fat and sugar handling. Pegozafermin is an engineered, longer-lasting version. ^R1 Related pages: Efruxifermin, Pemvidutide, Survodutide, Retatrutide.

Does it work?

Human MASH with F2-F3 fibrosis (ENLIVEN, n = 222): fibrosis improved in more treated patients than placebo; NASH resolution 23% to 37% vs 2%. ^{R1, R4}
Human Severe hypertriglyceridemia (n = 85 analyzed): median triglycerides −57.3% vs −11.9%; liver fat fell in an MRI sub-study. ^R5
Human Earlier phase 1b/2a in NASH: safety, pharmacokinetic and pharmacodynamic data. ^R7
Unknown Phase 3: ENTRUST (triglycerides) finished its primary phase in 2025 with no results posted; ENLIGHTEN-Fibrosis and ENLIGHTEN-Cirrhosis are recruiting, with primary completion listed for 2029 and 2028. ^{R12, R2, R3}

Is it safe?

Human Most common: nausea and diarrhea. ^R1 No serious drug-related events in the triglyceride trial. ^R5
Unknown No long-term data.

"Research" vials sold online: extra risks

A gray-market vial has no quality control and no guarantee of identity, strength or sterility. We test retail vials blind under the Open Peptide Standard; see /tests/. A passing test covers one batch on one date and does not mean the compound is safe.

Is it legal?

US: investigational only; not on FDA's 503A or 503B bulk-substance category lists and not on FDA's compounding safety-risk page. ^{R9, R10, R11}
Sport: WADA S2.3 prohibits fibroblast growth factors as a class; pegozafermin is not named. ^R8

Study details

These are amounts researchers used, not recommendations.

Study	People / model	Route	Amount used	Follow-up	Reported	Citation
ENLIVEN phase 2b 2023	222 adults, MASH F2-F3	SC	15 or 30 mg weekly; 44 mg every 2 weeks	24 weeks	Fibrosis and NASH resolution better than placebo	PMID 37356033
Phase 2 SHTG 2023	85 adults	SC	4 dose arms	8 weeks	TG −57.3% vs −11.9%	PMID 37355760

Full reference list (PubMed, CT.gov, FDA and WADA checked Oct 26, 2026)

^R1 Loomba R, et al. N Engl J Med. 2023. PMID 37356033
^R2 ClinicalTrials.gov NCT06318169, Hoffmann-La Roche, ENLIGHTEN-Fibrosis phase 3 in MASH F2-F3, recruiting, n = 1,350, primary completion Feb 2029 (CT.gov API v2, checked Oct 26, 2026). https://clinicaltrials.gov/study/NCT06318169
^R3 ClinicalTrials.gov NCT06419374, Hoffmann-La Roche, ENLIGHTEN-Cirrhosis phase 3, recruiting, n = 1,800, primary completion Jun 2028 (CT.gov API v2, checked Oct 26, 2026). https://clinicaltrials.gov/study/NCT06419374
^R4 ClinicalTrials.gov NCT04929483, 89bio, ENLIVEN phase 2b in MASH F2-F3, completed, n = 222 (CT.gov API v2, checked Oct 26, 2026). https://clinicaltrials.gov/study/NCT04929483
^R5 Bhatt DL, et al. Nat Med. 2023. PMID 37355760
^R6 ClinicalTrials.gov NCT04541186, 89bio, phase 2 in severe hypertriglyceridemia, completed, n = 86 (CT.gov API v2, checked Oct 26, 2026). https://clinicaltrials.gov/study/NCT04541186
^R7 Loomba R, et al. Lancet Gastroenterol Hepatol. 2023. PMID 36521501
^R8 WADA. The 2026 Prohibited List, S2.3 Growth factors (FGFs) class; pegozafermin not named. https://www.wada-ama.org/sites/default/files/2025-09/2026list_en_final_clean_september_2025.pdf
^R9 FDA, 503A bulk drug substances categories list (updated May 14, 2026). https://www.fda.gov/media/94155/download
^R10 FDA, 503B bulk drug substances categories list (updated Mar 21, 2025). https://www.fda.gov/media/94164/download
^R11 FDA, Certain bulk drug substances for use in compounding that may present significant safety risks (content current Apr 22, 2026). https://www.fda.gov/drugs/human-drug-compounding/certain-bulk-drug-substances-use-compounding-may-present-significant-safety-risks
^R12 ClinicalTrials.gov NCT05852431, 89bio, ENTRUST phase 3 in severe hypertriglyceridemia, completed Jul 2025 (primary), n = 369, no results posted (CT.gov API v2, checked Oct 26, 2026). https://clinicaltrials.gov/study/NCT05852431

Disclaimer

This page is for education and harm reduction, not medical advice or a recommendation to use Pegozafermin. Pegozafermin is only available in clinical trials. Talk to your doctor about approved treatments or trial enrollment. Report problems to FDA MedWatch (https://www.fda.gov/safety/medwatch).