Overview

Pemvidutide (ALT-801) is a once-weekly, balanced 1:1 GLP-1/glucagon dual receptor agonist developed by Altimmune, Inc. (Nasdaq: ALT), distinguished by its equal affinity for both GLP-1 and glucagon receptors — a design that maximizes direct hepatic fat oxidation effects alongside central appetite suppression. In Phase 2 obesity trials (MOMENTUM, 48 weeks), pemvidutide produced 15.6% weight loss at 2.4 mg with a landmark finding: only 21.9% of weight loss was lean mass (versus up to 40% for some GLP-1 comparators), representing class-leading lean mass preservation. Phase 2b IMPACT trial in MASH (biopsy-confirmed F2/F3 fibrosis) showed statistically significant improvements in non-invasive markers of fibrosis (ELF, LSM) at 48 weeks, and FDA End-of-Phase 2 meeting supports advancing to Phase 3 in MASH. FDA has granted Fast Track designation for pemvidutide in both MASH and alcohol use disorder (AUD). Phase 2 trials are also ongoing in AUD and alcohol-associated liver disease (ALD).

Mechanism of Action

Balanced 1:1 GLP-1/glucagon receptor agonism: GLP-1R activation suppresses appetite and enhances insulin secretion; GCGR activation directly drives hepatic fatty acid oxidation and thermogenesis. The equal receptor ratio maximizes direct liver effects while GLP-1 counterbalances glucagon's hyperglycemic potential. This mechanism explains superior MASH efficacy and class-leading lean mass preservation (only 21.9% of weight loss is lean tissue).

Potential Benefits

  • Phase 2 MOMENTUM (obesity, 48 weeks): 15.6% weight loss at 2.4 mg
  • Class-leading lean mass preservation: only 21.9% of weight loss from lean mass (vs. ~40% for GLP-1-only drugs)
  • Phase 2b IMPACT (MASH, 48 weeks): statistically significant ELF and LSM reductions
  • 75.2% relative reduction in liver fat at 24 weeks (1.8 mg dose)
  • 84.6% of patients achieved ≥50% liver fat reduction at 24 weeks (1.8 mg)
  • ALT reduction of 37.4 IU/L (IMPACT, 1.8 mg vs. -10.3 IU/L placebo)
  • 7.5% weight loss in MASH patients at 48 weeks (1.8 mg, no plateau)
  • FDA Fast Track designation for MASH and Alcohol Use Disorder
  • End-of-Phase 2 FDA meeting: supports Phase 3 registration trial in F2/F3 MASH
  • Blood pressure reductions and 'cardioprotective' lipid profile improvements
  • Phase 2 initiated for AUD (RECLAIM) and ALD (RESTORE) — May/July 2025

Research Dosage Notes

The following reflects doses used in published research studies. This is not medical advice.

Consult published research literature for study-specific protocols.

Routes of Administration

Subcutaneous Injection High

Once-weekly SC injection; studied at doses of 1.2–2.4 mg. Peptide-based with fatty acid side chain for albumin binding and extended half-life. Standard abdominal/thigh injection sites.

Stacking Protocols

Popular research stacks involving Pemvidutide:

Metabolic Health Stack

Combines Pemvidutide with MOTS-c (mitochondrial metabolism) and AOD-9604 (lipolysis) for metabolic optimization.

Reconstitution

StorageRefrigerate at 2-8°C after reconstitution. Do not freeze reconstituted solution.

Typical vial sizes: 5 mg. Add bac water slowly down the side of the vial, swirl gently — do not shake. Use insulin syringe for precise dosing.

Need exact syringe measurements?

Amino Acid Sequence

Proprietary Altimmune sequence; balanced 1:1 GLP-1/glucagon dual receptor agonist peptide with fatty acid conjugation for once-weekly dosing

Side Effects & Safety

  • Nausea (GLP-1 class effect, dose-dependent)
  • Vomiting (less frequent than GLP-1-only therapies)
  • Diarrhea
  • Decreased appetite
  • Extremely low discontinuation rate due to adverse events: 0% at 1.2 mg, 1.2% at 1.8 mg vs. 3.5% placebo in IMPACT
  • No severe or serious treatment-related adverse events in MASH trial
  • No significant hypoglycemia (GLP-1 counterbalances glucagon's glycogenolytic effect)
  • Injection site reactions (occasional)
  • Favorable tolerability profile is a key clinical differentiator

Safety & Contraindications

This information is for educational purposes only. Consult a qualified healthcare provider before using any peptide.

Absolute

MTC/MEN2

GLP-1 component carries standard thyroid C-cell tumor risk. Contraindicated in MTC/MEN2 patients.

Relative

Hepatic Impairment

Glucagon receptor agonism affects hepatic glucose output. Use caution in patients with severe hepatic impairment (Child-Pugh C).

Relative

Heart Rate Concerns

Glucagon component may increase heart rate. Monitor in patients with cardiovascular disease or arrhythmias.

Relative

Pregnancy & Lactation

Not studied in pregnancy. Avoid use.

Drug Interactions

  • Insulin/sulfonylureas: Dual GLP-1/glucagon agonism affects glucose metabolism. Risk of hypoglycemia with insulin; risk of hyperglycemia without proper monitoring.
  • Warfarin: Significant weight loss may alter warfarin pharmacokinetics. Monitor INR closely during treatment.

Pharmacokinetics

Half-Life~7 days (once-weekly dosing; fatty acid conjugation for albumin binding)
StorageRefrigerate at 2–8°C; do not freeze; protect from light

Synergistic Compounds

The following compounds have been studied alongside Pemvidutide for potential complementary or synergistic effects:

Learn More

References & Further Reading