Company: ABUS
Filing Date: 2025-11-13
Form Type: 10-Q
Source: 0001447028-25-000126
Chunk: 54

Company: Arbutus Biopharma Corp
Filing Date: 2025-11-13
Form: 10-Q
Item: Part I, Item 1
Chunk 54
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dusiran-related treatment emergent adverse events (TEAEs) were injection site bruising and transient alanine aminotransferase elevations, which occurred in association with decreasing HBsAg levels and/or markers of immune activation, and which returned to baseline values in all instances. The IFN-related TEAEs were consistent with the known safety profile of IFN. 

IM-PROVE II Phase 2a proof-of-concept clinical trial evaluating imdusiran in combination with Barinthus’ VTP-300

Through a clinical collaboration agreement with Barinthus that we entered into in July 2021, we completed IM-PROVE II, a Phase 2a proof-of-concept clinical trial evaluating the safety, antiviral activity and immunogenicity of a combination treatment with Barinthus’ VTP-300, an HBV immunotherapy, administered after imdusiran in patients with cHBV infection. The initial trial design enrolled 40 NA-suppressed, HBeAg negative or positive, non-cirrhotic cHBV infected patients. Our primary intent for this trial was to initially lower HBsAg, HBV DNA and HBV RNA levels with imdusiran and then administer VTP-300 as an immunomodulator to promote anti-HBV immune reawakening. All patients received imdusiran (60mg every 8 weeks, 4 doses) plus NA therapy for 24 weeks. After week 24, treatment with imdusiran was stopped. Patients continued only on NA therapy and were randomized to receive VTP-300 or placebo at week 26 and week 30. At week 48, all patients were evaluated for eligibility to discontinue NA therapy and were followed for an additional 24 to 48 weeks. Subsequently, we amended the IM-PROVE II clinical trial protocol to include another cohort that received imdusiran, VTP-300, NA therapy and low dose nivolumab, an approved PD-1 inhibitor in oncology. In this additional cohort, patients received imdusiran (60mg every 8 weeks, 4 doses) plus NA therapy for 24 weeks, followed by administration of VTP-300 plus up to two low doses of nivolumab while remaining on NA therapy. At week 48, all patients were evaluated for eligibility to discontinue NA therapy, and were followed for an additional 24 to 48 weeks. 

The cohort that included low