Arbutus Biopharma (ABUS) Status Update summary

Pipeline overview and strategy

• Focused on achieving a functional cure for hepatitis B, affecting 250 million globally.

• Lead asset imdusiran is an RNAi therapeutic in phase 2, targeting all HBV transcripts and reducing surface antigen.

• AB-101, a small molecule PD-L1 inhibitor, aims to address immune checkpoint blockade in HBV.

Recent clinical data and differentiation

• IMPROVE-1 phase 2a study showed a 25% functional cure rate overall, and 50% in patients with baseline surface antigen <1,000.

• Imdusiran demonstrated strong safety and tolerability, with seroconversion observed in functional cure patients.

• Imdusiran is dosed every eight weeks at 60 mg, lower and less frequent than competitors.

• Differentiation attributed to unique siRNA sequence, modifications, and GalNAc delivery.

Market relevance and patient impact

• Functional cure rates of 15–25% are considered meaningful by physicians and patients.

• About 40% of HBV patients globally have baseline surface antigen <1,000, representing a large addressable market.

• In the US, this translates to a significant patient population.

• Achieving functional cure reduces risk of HCC and addresses compliance issues with lifelong therapy.