Company: ABUS
Filing Date: 2025-11-13
Form Type: 10-Q
Source: 0001447028-25-000126
Chunk: 53

Company: Arbutus Biopharma Corp
Filing Date: 2025-11-13
Form: 10-Q
Item: Part I, Item 1
Chunk 53
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 24-week follow-up period, and then discontinued NA treatment, provided they met protocol-defined NA therapy discontinuation criteria. Patients who discontinued NA therapy entered an intensive follow-up period for 48 weeks.

Select key data from 12 patients in Cohort A1 of this Phase 2a clinical trial who received 6 doses of imdusiran, 24 weeks of IFN and ongoing NA therapy, as presented at the AASLD – The Liver Meeting in November 2024, include:

•50% (3/6) of patients with baseline HBsAg <1000 IU/mL achieved a functional cure.

•Overall, 25% (3/12) of patients achieved a functional cure.

•Those patients that achieved a functional cure also seroconverted with anti-HBs levels increasing as patients lost HBsAg.

At the EASL Congress in May 2025, we presented a poster characterizing the demographics and virological markers of the six cHBV patients across dosing cohorts in the IM-PROVE I Phase 2a clinical trial who achieved functional cure. The data showed that HBsAg at baseline was the only apparent marker in common associated with functional cure. In a second poster, we reported that patients who achieved functional cure in the 24-week IFN treatment cohorts experienced HBsAg seroclearance that was associated with transient HBV RNA elevations that were preceded by or coincided with increases in immunological markers. At the AASLD – The Liver Meeting in November 2025, we presented new analysis from our IM-PROVE I Phase 2a clinical trial showing beneficial clinical outcomes were observed across all evaluated HBV genotypes (A to E). 

Additionally, a total of 10 patients in IM-PROVE I who did not achieve functional cure were still able to remain off NA therapy for at least 48 weeks after discontinuing NA therapy following treatment with imdusiran. Across all cohorts and all baseline HBsAg levels, 37% (16/43) of patients either achieved functional cure or remained off NA therapy for at least 48 weeks after discontinuing NA therapy following treatment with imdusiran at 60mg.

These data from the IM-PROVE I trial suggest that the combination of imdusiran and IFN was generally safe and well-tolerated. There were no serious adverse events related to imdusiran, IFN or NA therapy, and no adverse events leading to discontinuation. The most common im