Altimmune (ALT) Study Result summary

Study design and population

• The phase II-B/2b IMPACT trial enrolled 212 adults with biopsy-confirmed MASH (F2/F3), BMI ≥27, and liver fat ≥8%, randomized to placebo, pemvidutide 1.2 mg, or 1.8 mg weekly for 24 weeks, with primary endpoints assessed at 24 weeks.

• Baseline characteristics were balanced across groups, including age, sex, BMI, diabetes status, and fibrosis stage.

• Eligibility required F2/F3 MASH, ≥8% liver fat by MRI-PDFF, and BMI ≥27.

• Primary and secondary endpoints included MASH resolution, fibrosis improvement, weight loss, non-invasive fibrosis tests, safety, and tolerability.

• High completion rates and minimal discontinuations due to adverse events were observed.

Efficacy results

• Statistically significant MASH resolution without worsening of fibrosis at 24 weeks: up to 59.1% (1.2 mg), 52.1% (1.8 mg) vs. 19.1% for placebo (p<0.0001, ITT analysis).

• Fibrosis improvement without worsening of MASH observed in up to 34.5% of subjects, with AI-based analysis showing up to 30.6% (1.8 mg) achieving ≥60% fibrosis reduction vs. 8.2% placebo.

• Significant improvements in non-invasive fibrosis tests (ELF, VCTE) and ALT levels, with little placebo effect.

• Liver fat content reduced by up to 62.8%, with normalization (<5% LFC) in up to 44.3% of subjects.

• Composite endpoint (MASH resolution + fibrosis improvement) nearly doubled placebo response and approached statistical significance.

Weight loss and metabolic effects

• Weight loss up to 6.2% at 24 weeks (1.8 mg), with no plateauing observed and higher weight loss expected at 2.4 mg dose.

• Glycemic control maintained with minimal changes in HbA1C regardless of diabetes status; systolic blood pressure reduced by up to 6.6 mmHg.