Arbutus Biopharma Corporation

Company overview. Arbutus Biopharma Corporation (Nasdaq: ABUS) is a clinical-stage biopharmaceutical company incorporated in 2005, headquartered in Warminster, Pennsylvania. It was formerly Tekmira Pharmaceuticals Corporation, renamed Arbutus in July 2015. It is publicly traded with no parent company. Its FY2025 Form 10-K reports a 57% workforce reduction during 2025 and restructuring that included exiting its corporate headquarters; headcount was reported at 19 employees as of December 31, 2025, with FY2025 revenue of about $14.1 million and a market capitalization in the high hundreds of millions of dollars.

Operations. Arbutus develops therapeutics for chronic hepatitis B (cHBV). Its pipeline consists of imdusiran (AB-729), a GalNAc-conjugated, subcutaneously delivered RNAi therapeutic in Phase 2a development (FDA Fast Track designation), and AB-101, an oral PD-L1 inhibitor in Phase 1a/1b. It also holds and licenses lipid nanoparticle (LNP) delivery patents and co-founded the LNP licensing company Genevant Sciences with Roivant Sciences, of which Genevant is now a subsidiary. It has a licensing agreement with Alnylam Pharmaceuticals and receives ONPATTRO royalties.

Litigation posture. An operating company that is predominantly a defensive litigant: six of seven tracked matters list Arbutus as defendant, one as plaintiff. The defensive cases consist largely of patent-office and appellate challenges to its LNP patents brought by Moderna (2018 and 2019 PTAB IPRs, and the 2020 Federal Circuit appeal), plus Acuitas Therapeutics' 2022 SDNY suit naming Genevant. Its sole plaintiff action was the 2022 Delaware infringement suit against Moderna. There is no NPE-style filing cluster, and none of the tracked matters sit in the Eastern District of Texas.

Notable cases. The central matter is Arbutus/Genevant v. Moderna (D. Del., filed February 28, 2022), asserting LNP patents against Spikevax and mRESVIA. In March 2026 the parties announced a global settlement providing $950 million upfront, plus up to $1.3 billion contingent on Moderna's pending Federal Circuit appeal of the Section 1498 government-contractor ruling — the appeal tracked as the March 2026 Federal Circuit matter. Genevant's separate LNP litigation against Pfizer/BioNTech remains ongoing.