89bio, Inc. announced additional data from a post-hoc analysis of the ENLIVEN Phase 2b trial evaluating treatment with pegozafermin in a subgroup of patients with F4 NASH. These data were featured in an oral presentation during the AASLD The Liver Meeting®, being held in Boston, Massachusetts. The ENLIVEN Phase 2b trial enrolled 14 patients who initially met the study histological inclusion criteria of fibrosis F2 or F3 and were subsequently re-classified as having F4 fibrosis by the consensus panel.

The 14 patients? baseline characteristics were generally consistent with a well-compensated F4 population featuring higher percentage of patients with diabetes, higher PRO-C3, increased liver stiffness as measured by VCTE, and lower platelet counts. Treatment with pegozafermin led to clinically meaningful improvements in liver specific biomarkers of stiffness and fibrosis (Pro-C3, FAST, VCTE, FIB-4), inflammation (ALT and AST), and other key non-invasive markers.

In a responder analysis, a significant proportion of patients identified as responders through NITs at the 24-week mark also exhibited histologically confirmed fibrosis improvement. These data, while preliminary, suggest a potential correlation between NIT-based improvements and histological measures of fibrosis reduction. Five out of 11 pegozafermin-treated patients experienced at least one-stage improvement in liver fibrosis with no worsening of NASH by week 24 (45%) compared with zero out of one patient on placebo.

Additionally, as previously reported, nine out of the 11 pegozafermin-treated patients had fibrosis improvement (82%) compared with zero out of one patient on placebo. Safety and tolerability in the F4 patients was consistent with the favorable profile observed with the primary analysis of ENLIVEN reported earlier this year and prior studies in the pre-cirrhotic patient population. Across dose groups, the most frequently reported treatment-related adverse events were Grade 1 or 2 diarrhea and injection site reaction.