Arbutus Biopharma Corporation announced pipeline updates including its continued focus on its hepatitis B virus (HBV) assets, imdusiran (AB-729) as a cornerstone therapy in a functional cure treatment regimen for patients with chronic hepatitis B virus (cHBV), as well as its oral PD-L1 inhibitor, AB-101. In addition, the Company is discontinuing development of its oral RNA destabilizer, AB-161, due to a pre-clinical toxicology finding not related to peripheral neuropathy. There were no safety issues reported in the healthy subjects that received single doses of AB-161 in the Phase 1 clinical trial.

The company is also discontinuing its efforts to identify and develop a coronavirus combination therapy that included AB-343 its Mpro candidate, due to an unfavorable PK profile noted in the IND-enabling studies, and a potential nsp12 polymerase inhibitor. These pipeline changes are expected to extend the Company's cash runway through Third Quarter 2025. The Company remains on track to report preliminary data in the fourth quarter of this year from the Phase 2a clinical trial with imdusiran and Vaccitech's VTP-300 in patients with cHBV.

In addition, the Company has dosed the first subject in its Phase 1a/1b clinical trial with its oral PD-L1 inhibitor, AB-101, for HBV and expects preliminary data in the first half of 2024. The AB-101-001 Phase 1a/1b double-blind, randomized, placebo-controlled, clinical trial is designed to investigate the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of single and multiple oral doses of AB-101 for up to 28 days in healthy subjects and patients with cHBV. The trial will be conducted in three parts starting with single ascending doses in up to 64 healthy subjects, followed by multiple ascending doses in up to 40 healthy subjects and culminating with multiple doses in up to 60 patients with cHBV.

Safety and PK/PD assessments will be performed prior to dose escalation in all study parts. Initial data from part one of the clinical trial are expected in the first half of 2024. These pipeline updates will not impact the Company's pending litigations.

Arbutus will continue to protect and defend its intellectual property, which is the subject of the on-going lawsuits against Moderna and Pfizer/BioNTech. The Company is seeking fair compensation for Moderna's and Pfizer/BioNTech's use of its patented LNP technology that was developed with great effort and at a great expense, without which Moderna and Pfizer/BioNTech's COVID-19 vaccines would not have been successful. Document production is currently on-going in the lawsuit against Moderna with the claim construction hearing scheduled for February 7, 2024.

There are no updates to the status of the Pfizer/BioNTech lawsuit at this time.