89bio, Inc. announced positive topline data from the blinded extension phase of its Phase 2b ENLIVEN trial evaluating treatment with pegozafermin in patients with nonalcoholic steatohepatitis (NASH). At week 48, both the 30mg weekly (QW) and 44mg every-two-week (Q2W) dosing schedules of pegozafermin demonstrated statistically significant improvements across key markers of liver health. The benefits observed at week 48 were consistent with the results observed at week 24, indicating sustained benefits over time.

ENLIVEN Extension Data: Patients in ENLIVEN continued in a blinded extension phase for an additional 24 weeks (Extension Phase) past the primary endpoint at week 24 (Main Study), for a total treatment period of 48 weeks. A subset of patients in the placebo arm of the Main Study (n=19) were re-randomized to receive pegozafermin 30mg weekly (QW) during the Extension Phase. The efficacy endpoints assessed in the Extension Phase included liver fat, non-invasive markers of fibrosis and inflammation, and metabolic markers.

Per the protocol, these patients did not undergo biopsies at week 48. Treatment Effects Were Robust and Consistent across Patient Sub-groups: Patients on Background GLP-1 Therapy: Consistent with results observed in the Main Study, patients on background GLP-1 therapy who received pegozafermin continue to derive a greater benefit on markers of liver fibrosis, liver injury/inflammation, liver fat and lipids, compared to patients who continued GLP-1 therapy in the placebo group. Patients entering ENLIVEN on background GLP-1 therapies were required to have been on a stable regimen for at least six months.

Patients Re-randomized from Placebo to Pegozafermin: The patients re-randomized to receive 30mg QW during the Extension Phase demonstrated robust improvements in NITs of liver fibrosis, liver injury/inflammation, and liver fat following 24 weeks of treatment with pegozafermin after experiencing minimal to no change during the first 24 weeks on placebo. Patients in the re-randomized group serve as their own control and thus provide independent compelling evidence of pegozafermin's rapid and robust therapeutic effects. Pegozafermin continued to demonstrate a favorable safety and tolerability profile at week 48, consistent with previously reported data.

The most common treatment-emergent adverse events were Grade 1 or 2 gastrointestinal events. Incidence rates of adverse events remained generally stable between week 24 and week 48 with no new patients on pegozafermin reporting diarrhea or nausea during the Extension Phase. At week 48, no clinically meaningful or statistically significant changes in bone mineral density or bone biomarkers were observed relative to placebo.

No clinically meaningful or statistically significant changes in blood pressure or heart rate were observed relative to placebo.