---
schema_version: "secwatch.filing_event.v1"
accession: "0001171843-24-003302"
form_type: "8-K"
ticker: "ABUS"
cik: "0001447028"
company_name: "Arbutus Biopharma Corp"
filed_at: "2024-06-05T23:59:59+00:00"
generated_at: "2026-06-01T06:14:24.277360+00:00"
event_type: "other_material"
sentiment: "positive"
materiality_score: 0.75
calibrated_materiality_score: 0.75
confidence: "high"
source: SEC EDGAR
---

# Arbutus Phase 2a: imdusiran+IFN yields sustained undetectable HBsAg in 33% at 24 weeks

## Summary
- 33.3% (4/12) on 48wk imdusiran + 24wk IFN had undetectable HBsAg at EOT, sustained 24wk post-treatment.
- All six patients with sustained HBsAg loss seroconverted with high anti-HBsAg antibodies (43.8 to >1,000 mIU/mL).
- Two of six patients stopped all therapy and maintain undetectable HBsAg and HBV DNA at 12 weeks off therapy.
- No SAEs related to imdusiran or IFN; most common TEAEs were transient ALT elevations and injection site bruising.

## SEC filing metadata
- accession: 0001171843-24-003302
- form_type: 8-K
- ticker: ABUS
- cik: 0001447028
- company_name: Arbutus Biopharma Corp
- filed_at: 2024-06-05T23:59:59+00:00
- event_type: other_material
- sentiment: positive
- materiality_score: 0.75
- calibrated_materiality_score: 0.75
- confidence: high
- sec_items: 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1447028/000117184324003302/0001171843-24-003302-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1447028/000117184324003302/f8k_060424.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001171843-24-003302
- JSON: https://secwatch.observer/filing/0001171843-24-003302.json
- Plain text: https://secwatch.observer/filing/0001171843-24-003302.txt

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