Pemvidutide

Pemvidutide (formerly ALT-801) is an investigational, peptide-based GLP-1/glucagon dual receptor agonist with a balanced 1:1 ratio, developed by Altimmune for obesity and MASH (metabolic dysfunction-associated steatohepatitis). GLP-1 suppresses appetite while glucagon increases energy expenditure and directly reduces liver fat — a combination mimicking diet-and-exercise effects. It holds FDA Fast Track designations (MASH and alcohol use disorder) and, since January 5, 2026, Breakthrough Therapy designation for MASH, and in August 2026 Altimmune began the global PERFORMA Phase 3 MASH trial — but it is not approved anywhere as of August 2026.

Sources: Altimmune Receives FDA Breakthrough Therapy Designation for Pemvidutide in MASH, Altimmune, via GlobeNewswire (company release); Altimmune Initiates PERFORMA Phase 3 Trial of Pemvidutide in Patients with MASH, Altimmune, via GlobeNewswire (company release)

What is Pemvidutide and why does GLP-1/glucagon agonism matter?

Pemvidutide pairs GLP-1's appetite suppression with glucagon's energy-expenditure and hepatic fat-reducing effects — the same dual-agonist class as survodutide and mazdutide, tuned to a balanced 1:1 activity. Its notable clinical signature is high lean-mass preservation during weight loss.

What does the clinical evidence show?

In the Phase 2 MOMENTUM obesity trial, once-weekly pemvidutide produced up to ~15.6% mean weight loss at 48 weeks with class-leading lean-mass preservation (most weight lost was fat); Phase 2b MASH data (IMPACT) were more mixed on liver endpoints. In MASH, the IMPACT Phase 2b trial (212 adults with biopsy-confirmed MASH and F2–F3 fibrosis, randomized to placebo or 1.2 mg / 1.8 mg weekly) met its 24-week primary endpoint: MASH resolution without worsening of fibrosis in 58% (1.2 mg) and 52% (1.8 mg) of participants versus 20% on placebo (both p<0.0001). Fibrosis improvement (33–36% vs 28% placebo) did not clearly separate from placebo at 24 weeks — the more mixed liver endpoint — and weight loss in this population was 4.8–5.8% at 24 weeks. The 24-week results were published in The Lancet in November 2025. A company-reported 48-week analysis (topline, December 2025; not yet peer-reviewed) described continued improvements in non-invasive fibrosis markers, liver-fat content, and weight, with no weight-loss plateau at the 1.8 mg dose.

Source: Safety and efficacy of weekly pemvidutide versus placebo for metabolic dysfunction-associated steatohepatitis (IMPACT): 24-week results from a multicentre, randomised, double-blind, phase 2b study, Noureddin M. et al. (optional, non-blocking: complete list), Lancet, 2025 · Evidence level: phase 2 (RCTs); not approved

What are the known side effects and safety concerns?

Reported effects are predominantly GLP-1-class gastrointestinal events; the balanced glucagon component is being evaluated for cardiometabolic effects. In the published IMPACT trial, adverse events led to treatment discontinuation in 0–1% of pemvidutide participants versus 2% on placebo at the 24-week analysis. Full safety awaits later-stage data.

Source: Safety and efficacy of weekly pemvidutide versus placebo for metabolic dysfunction-associated steatohepatitis (IMPACT): 24-week results from a multicentre, randomised, double-blind, phase 2b study, Noureddin M. et al. (optional, non-blocking: complete list), Lancet, 2025 · Evidence level: phase 2

What is the regulatory status, and why is verification critical here?

Pemvidutide is investigational and not approved by the FDA or any other regulator as of August 2026 — Breakthrough Therapy designation speeds review interactions but is not an approval — and it is not commercially available anywhere — so any "pemvidutide" sold through research-chemical vendors is not from Altimmune and is unverified. Independent identity confirmation is the only meaningful check. See the legal status guide.

How does Peptigrity verify Pemvidutide?

Peptigrity collects independent third-party Certificates of Analysis for pemvidutide from shops' official channels and verifies each for authenticity before publishing. Because shops choose which COAs to publish, results reflect the batches shops have made public rather than every production batch — a selection bias we state openly. A community-funded Testing Grant to purchase and test vials anonymously is in development. Tests in the database come from independent labs such as Janoshik Analytical, Freedom Diagnostics, and Chromate. No independent pemvidutide lab tests are on file yet (verified August 2026) — for an investigational compound with no reference product, an identity-confirmed, batch-matched COA is the only meaningful buyer signal. The trust score weights lab purity and reviews equally (50/50). See how to read lab results.

This section is for educational and informational purposes only and does not constitute medical advice. Pemvidutide is not approved by the FDA or equivalent regulators for human use. Always consult a qualified healthcare provider before using any peptide or research compound. Peptigrity is an independent review platform and does not sell, endorse, or recommend specific products or vendors.

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