Moderna settlement cash dwarfs the drug pipeline — imdusiran's Phase 2b initiation determines whether Arbutus is a biotech or a patent holding company returning capital

Arbutus is a clinical-stage biotech developing imdusiran, an RNA therapy for chronic hepatitis B infection, which is not yet approved.

Arbutus collected $178M from Moderna's LNP settlement and is returning roughly $230M to shareholders, leaving imdusiran, an siRNA targeting chronic hepatitis B, as the residual clinical bet. Ten patients achieved functional cure in Phase 2a, with six sustaining it beyond two years, but the thesis resolves on whether a Phase 2b trial produces registrational-quality functional cure rates with adequate durability. The company discontinued in-house research and cut its workforce, meaning imdusiran now advances with no platform backstop if the trial disappoints.