Arbutus Reports First Quarter 2021 Financial Results and Provides Corporate Update

AB-729, Arbutus’ proprietary subcutaneously delivered RNAi agent, continues to demonstrate robust and continuous declines in hepatitis B surface antigen (HBsAg) in subjects with chronic hepatitis B (HBV) with favorable safety and tolerability data

Additional data from the ongoing Phase 1a/1b clinical trial of AB-729, including 60 mg multi-dose data (dosing interval every 4 and 8 weeks) and 90 mg multi-dose data (dosing interval every 8 weeks), expected in 2Q/2021

A proof-of-concept Phase 2 triple combination clinical trial evaluating AB-729, and Assembly Biosciences’ core inhibitor candidate, vebicorvir (VBR), with an approved standard of care nucleoside/nucleotide reverse transcript (NRTI) initiated by Arbutus and Assembly in 1Q/2021

Phase 1a/1b clinical trial with AB-836, Arbutus’ proprietary oral capsid inhibitor, initiated with initial data expected in 2H/2021

Arbutus, X-Chem, and Proteros biostructures announced an innovative Pan-Coronavirus Discovery Research and License Agreement in April 2021

Conference Call and Webcast Scheduled Today at 8:45 AM ET

WARMINSTER, Pa., May 05, 2021 (GLOBE NEWSWIRE) -- Arbutus Biopharma Corporation (Nasdaq: ABUS), a clinical-stage biopharmaceutical company primarily focused on developing a cure for people with chronic hepatitis B virus (HBV) infection, as well as therapies to treat coronaviruses (including COVID-19), today reports its first quarter 2021 financial results and provides a corporate update.

William Collier, President and Chief Executive Officer of Arbutus, stated, “We had a productive first quarter of 2021. With the initiation of the Phase 1a/1b clinical trial of AB-836, our oral capsid inhibitor, together with the ongoing clinical development of AB-729, we now have two proprietary HBV agents in development. This progress reflects our objective to develop a combination regimen that provides a functional cure for people living with HBV. We were also gratified to establish an innovative collaboration with X-Chem, Inc. and Proteros biostructures GmbH. The objective of this alliance is to expedite our efforts to discover an effective oral antiviral therapy against coronaviruses including SARS-CoV-2 targeting the main protease.”

Mr. Collier added, “Looking ahead, we expect an eventful 2021 including: continued longer term Phase 1a/1b dosing results for AB-729; initiation of two Phase 2 proof-of-concept clinical trials for AB-729 with one or more approved or investigational agents; and initial Phase 1a/1b data from our proprietary oral capsid inhibitor, AB-836.”

Pipeline Update

AB-729

• Arbutus is currently conducting a single- and multi-dose Phase 1a/1b clinical trial to determine the safety, tolerability, pharmacokinetics, and pharmacodynamics of AB-729 in healthy subjects and in subjects with chronic HBV infection.
• Results to date demonstrate that treatment of AB-729 using the 60 mg and 90 mg doses has been well tolerated after a single dose. Efficacy results to date suggest that repeat dosing using the 60 mg dose every 4 weeks resulted in a continuous and robust mean HBsAg decline at week 24 (-1.84 log10 IU/mL, N=7). Repeat dosing using the 60 mg dose every 8 weeks results in comparable mean HBsAg declines relative to the 60 mg dose every 4 weeks at week 16 (-1.39 log10 IU/mL vs -1.44 log10 IU/mL, p