---
schema_version: "secwatch.filing_event.v1"
accession: "0001171843-23-002864"
form_type: "8-K"
ticker: "ABUS"
cik: "0001447028"
company_name: "Arbutus Biopharma Corp"
filed_at: "2023-05-04T23:59:59+00:00"
generated_at: "2026-06-15T21:35:30.784370+00:00"
event_type: "other_material"
sentiment: "negative"
materiality_score: 0.75
calibrated_materiality_score: 0.75
confidence: "high"
source: SEC EDGAR
---

# Arbutus Q1 rev down 47% to $6.7M; files patent suit vs Pfizer/BioNTech; AB-101 IND on hold

## Summary
- Q1 revenue $6.7M vs $12.6M YoY; net loss $16.3M ($0.10/shr) vs $15.8M ($0.11) YoY.
- Filed patent infringement lawsuit against Pfizer and BioNTech for COVID-19 LNP vaccine technology.
- FDA placed AB-101 (oral PD-L1) IND on clinical hold; Phase 1 not initiated, no patients dosed.
- Cash $178.5M; burn guidance reduced to $90-95M from $95-100M; runway into Q1 2025.
- Dosed first subject in Phase 1 trial for AB-161 (oral RNA destabilizer); data expected H2 2023.

## SEC filing metadata
- accession: 0001171843-23-002864
- form_type: 8-K
- ticker: ABUS
- cik: 0001447028
- company_name: Arbutus Biopharma Corp
- filed_at: 2023-05-04T23:59:59+00:00
- event_type: other_material
- sentiment: negative
- materiality_score: 0.75
- calibrated_materiality_score: 0.75
- confidence: high
- sec_items: 2.02, 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1447028/000117184323002864/0001171843-23-002864-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1447028/000117184323002864/f8k_050423.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001171843-23-002864
- JSON: https://secwatch.observer/filing/0001171843-23-002864.json
- Plain text: https://secwatch.observer/filing/0001171843-23-002864.txt

## Key facts
- Earnings Releases
  Arbutus Biopharma Corp updated its first quarter ended March 31, 2023 guidance (lowered).
  - Period: first quarter ended March 31, 2023
  - Guidance: lowered
  - Result: reported results
  source text: On May 4, 2023, Arbutus Biopharma Corporation (the “Company”) issued a press release announcing its financial results for the first quarter ended March 31, 2023 and certain other information.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1447028/000117184323002864/0001171843-23-002864-index.htm

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