Arbutus Biopharma Corp 8-K

What Happened
Arbutus Biopharma announced that on January 15, 2026 the Board of Appeal of the European Patent Office (EPO) issued a verbal decision revoking its European patent EP 2279254. The revocation follows Notices of Opposition originally filed in April 2018 by affiliates of Moderna Therapeutics, Inc. and Merck, Sharp & Dohme Corporation. The verbal decision was provided without reasons; a written decision is expected in the coming months and Arbutus plans to file a petition for review by the Enlarged Board of Appeal upon receipt of the written decision.

Key Details

• Date of EPO verbal decision: January 15, 2026.
• Patent affected: European patent EP 2279254 (the “’254 Patent”); earlier, the EPO Opposition Division had twice upheld an amended version.
• Opponents: Affiliates of Moderna and Merck filed oppositions in April 2018.
• Impact on litigation: EPO decision likely affects Arbutus/Genevant cases in Switzerland and Unified Patent Court case UPC_CFI_191/2025 (one of two UPC cases). Arbutus says the EPO “added matter” standard used in this decision does not apply in the U.S. or other jurisdictions where it has pending litigation and does not expect impact on its U.S., Japan or Canada cases, UPC_CFI_192/2025 (which does not involve the ’254 Patent), or its U.S. case against Pfizer/BioNTech.

Why It Matters
This is a material legal development for Arbutus because revocation of a European patent can alter the company’s enforcement position in Europe (including Switzerland and UPC proceedings) and may affect licensing or settlement leverage in those jurisdictions. The company intends to seek review at the EPO, and it says the decision rests on an EPO-specific legal standard (“added matter”) that it believes does not affect its pending cases outside the EPO framework. Investors should note the company’s warning that outcomes and timing of litigation remain uncertain and are subject to the risks disclosed in its SEC and Canadian filings.