---
schema_version: "secwatch.filing_event.v1"
accession: "0001171843-25-002841"
form_type: "8-K"
ticker: "ABUS"
cik: "0001447028"
company_name: "Arbutus Biopharma Corp"
filed_at: "2025-05-07T23:59:59+00:00"
generated_at: "2026-05-22T07:35:27.345526+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.65
calibrated_materiality_score: 0.65
confidence: "high"
source: SEC EDGAR
---

# Arbutus presents HBV functional cure data from imdusiran combo; AB-101 safety at EASL 2025

## Summary
- In Phase 2a IM-PROVE II, imdusiran + VTP-300 + low-dose nivolumab led to 15.3% functional cure rate (2/13) in patients with baseline HBsAg <1000 IU/mL.
- 3 patients in nivolumab cohort achieved HBsAg loss and seroconversion at week 48.
- AB-101 Phase 1a/1b Part 3: 10mg once daily for 28 days well tolerated with PD-L1 receptor occupancy similar to healthy volunteers; no liver dysfunction.
- Across all imdusiran Phase 2a trials, 8 patients functionally cured, 7 with baseline HBsAg <1000 IU/mL.

## SEC filing metadata
- accession: 0001171843-25-002841
- form_type: 8-K
- ticker: ABUS
- cik: 0001447028
- company_name: Arbutus Biopharma Corp
- filed_at: 2025-05-07T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.65
- calibrated_materiality_score: 0.65
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1447028/000117184325002841/0001171843-25-002841-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1447028/000117184325002841/f8k_050725.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001171843-25-002841
- JSON: https://secwatch.observer/filing/0001171843-25-002841.json
- Plain text: https://secwatch.observer/filing/0001171843-25-002841.txt

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.