Company: ABUS
Filing Date: 2025-11-13
Form Type: 10-Q
Source: 0001447028-25-000126
Chunk: 55

Company: Arbutus Biopharma Corp
Filing Date: 2025-11-13
Form: 10-Q
Item: Part I, Item 1
Chunk 55
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 dose nivolumab was the best performing cohort in the IM-PROVE II clinical trial. At the AASLD – The Liver Meeting in November 2024, we presented data from this clinical trial showing that the addition of low dose nivolumab increased rates of HBsAg seroclearance in cHBV patients and that 23% (3/13) of patients who received the treatment regimen with low dose nivolumab achieved HBsAg seroclearance by week 48. At the EASL Congress in May 2025, 

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we presented data showing that 25% (2/8) of patients with low dose nivolumab added to the treatment regimen and with baseline HBsAg<1000 IU/mL achieved functional cure.

Additionally, a total of 30 patients in IM-PROVE II 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 at 60mg. A total of 52% (32/62) 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, across all cohorts and all baseline HBsAg levels, and both HBeAg negative and positive patients. Treatment with imdusiran, VTP-300, NA therapy and low dose nivolumab in this clinical trial was generally safe and well-tolerated. There were no serious adverse events, Grade 3 or 4 adverse events, immune-related adverse events, or discontinuations due to adverse events.

The IM-PROVE II clinical trial was managed by us, subject to oversight by a joint development committee comprised of representatives from both companies. We and Barinthus retain full rights to our respective product candidates and split all costs associated with the clinical trial. Pursuant to the agreement, the parties could have undertaken a larger Phase 2b clinical trial depending on the results of the initial Phase 2a clinical trial. However, in January 2025, Barinthus announced a shift in its strategic business focus that included postponing further development of VTP-300 after its ongoing VTP-300 clinical trials have concluded. The parties do not intend to undertake a larger Phase 2b with this combination treatment regimen.  

At the AASLD - The Liver Meeting in November 2025, we presented cumulative data across all of our im