Company: ABUS
Filing Date: 2025-11-13
Form Type: 10-Q
Source: 0001447028-25-000126
Chunk: 52

Company: Arbutus Biopharma Corp
Filing Date: 2025-11-13
Form: 10-Q
Item: Part I, Item 1
Chunk 52
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 cHBV infection. Reducing HBsAg and HBV DNA are widely believed to be key prerequisites to enable a patient’s immune system to reawaken and respond against the virus.  

Imdusiran has the following advantages over other RNAi therapeutics in development for cHBV infection:

–Targeted to hepatocytes using our proprietary covalently conjugated GalNAc delivery technology which provides highly efficient liver-targeted uptake and enables subcutaneous dosing.

–Unique nucleotide sequence that is single trigger and targets all HBV transcripts including HBx from cccDNA and integrated HBV DNA.

–Specific chemical modifications and unique asymmetric RNA structure that reduces off-target effects while maintaining/enhancing potency and providing durable liver exposure and in vivo efficacy. 

–Delivered at a lower dose and less frequently (4, 8 or 12 week intervals).

–Immune activation properties with HBV-specific T-cell immune restoration and a decrease in exhausted T-cells in responder patients.

IM-PROVE I Phase 2a proof-of-concept clinical trial evaluating imdusiran in combination with IFN

We have completed IM-PROVE I, a randomized, open label, multicenter Phase 2a proof-of-concept clinical trial investigating the safety and antiviral activity of imdusiran in combination with a short course of IFN and ongoing NA therapy in 43 stably NA-suppressed, HBeAg negative, non-cirrhotic patients with cHBV infection. Our primary intent for this trial was to initially lower HBsAg, HBV DNA and HBV RNA levels with imdusiran and then administer IFN as an immunomodulator to promote 

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anti-HBV immune reawakening. Our belief in this trial was that if we can lower HBsAg and HBV DNA levels and promote immune reawakening, we may achieve sustained HBsAg seroclearance and HBV DNA <LLOQ, potentially leading to a functional cure. After patients received 24-weeks of dosing with imdusiran (60mg every 8 weeks, 4 doses) plus ongoing NA therapy, patients were randomized into one of four cohorts to receive a short course of IFN plus ongoing NA therapy for either 12 or 24 weeks, with or without up to two additional doses of imdusiran across an additional 16 week period. After completion of the assigned IFN treatment period, all patients remained on NA therapy for the initial