Altimmune’s Phase 2b IMPACT trial shows pemvidutide improves MASH biomarkers and fibrosis, reinforcing antifibrotic potential after 24 weeks.
Written By: Fariha Sameen, PharmD
Reviewed By: Pharmacally Editorial Team
Altimmune unveiled new analyses from its Phase 2b IMPACT trial (NCT05989711) at the EASL Congress 2026, showing that pemvidutide improved multiple non-invasive markers of metabolic dysfunction-associated steatohepatitis (MASH) activity and fibrosis after 24 weeks of treatment. The findings reinforce the investigational therapy’s potential antifibrotic activity and provide additional evidence of consistent treatment effects across liver fat, inflammation, and fibrosis markers.
Pemvidutide Mechanism
Pemvidutide is a balanced 1:1 glucagon/GLP-1 dual receptor agonist in development for MASH, alcohol use disorder, and alcohol-associated liver disease. Glucagon receptor activation reduces liver fat, inflammation, and fibrosis, while GLP-1 activity supports appetite suppression and weight loss.
Biomarker Improvements
The new analyses assessed overlapping improvements in liver fat content (LFC), alanine aminotransferase (ALT), liver stiffness measurement (LSM), and enhanced liver fibrosis (ELF) scores. The analyses showed consistent improvements across both inflammatory and fibrosis-related markers.
At the 1.2 mg dose, 37.8% of patients achieved both a greater than 0.5 reduction in ELF score and more than 30% reduction in LSM versus 8.3% with placebo (p=0.0002). At the 1.8 mg dose, 22.7% achieved the same endpoint compared with placebo (p=0.02).
Digital Pathology Findings
AI-based digital pathology using HistoIndex qFibrosis technology confirmed consistent antifibrotic activity. Continuous fibrosis values declined significantly with pemvidutide, while at least one-stage qFibrosis regression occurred in 68.6% of patients receiving 1.2 mg and 54.5% receiving 1.8 mg, compared with 29.6% on placebo.
Expert Commentary
Naim Alkhouri, Chief Medical Officer at Summit Clinical Research, said the consistency across non-invasive markers and histologic assessments supports pemvidutide’s broad effect on MASH disease biology and fibrosis progression.
Christophe Arbet-Engels, Chief Medical Officer at Altimmune, said the combined biomarker and imaging findings strengthen confidence in the durability and robustness of the treatment response.
Study Design
The randomized, double-blind IMPACT Phase 2b trial enrolled 212 patients with biopsy-confirmed MASH and F2–F3 fibrosis, with and without diabetes. Participants received weekly subcutaneous pemvidutide at 1.2 mg, 1.8 mg, or placebo for 48 weeks. Primary endpoints included MASH resolution without fibrosis worsening or fibrosis improvement without worsening MASH.
Next Steps
Altimmune plans to begin the global PERFORMA Phase 3 trial in the second half of 2026. Pemvidutide has received both Fast Track and Breakthrough Therapy designations from the FDA for MASH.
Reference
About the Writer
Fariha Sameen, PharmD (LinkedIn), is a clinical pharmacy professional with hands-on experience in patient counselling, medication review, therapeutic monitoring, and clinical documentation across multiple departments. She has experience identifying and assessing drug-related problems and supporting medication safety practices. Her interests include pharmacovigilance, ADR reporting, clinical research, and medical writing focused on clear, evidence-based communication.