Arbutus to Unveil Imdusiran Data at EASL 2024

Arbutus Biopharma Corporation, a clinical-stage biopharmaceutical entity recognized for its expertise in virology, has announced the acceptance of two abstracts for presentation at the European Association for the Study of the Liver (EASL) Congress 2024. The Congress will be held from June 5 to 8, 2024, in Milan, Italy.

The first abstract, numbered 2389, will be a poster presentation. It is titled "Imdusiran (AB-729) administered every 8 weeks in combination with 24 weeks of pegylated interferon alfa-2a in virally suppressed, HBeAg-negative subjects with chronic HBV infection leads to HBsAg loss in some subjects at end of IFN treatment." Presented by Prof. Man-Fung Yuen on June 5, 2024, this study observes that 28% of subjects who received 4 or 6 doses of imdusiran along with 24 weeks of interferon treatment showed HBsAg at or below the lower limit of quantification with detectable anti-HBs at the end of treatment. Contrarily, none of the subjects who received 4 or 5 doses of imdusiran combined with 12 weeks of interferon showed similar results. As the study is still ongoing, additional data on end-of-treatment, durability of HBsAg loss, and initial immunology data for some study participants will be shared. This poster will also be highlighted on June 6 in the Poster Tour focusing on viral hepatitis B and D, particularly new or unapproved therapies or strategies.

The second abstract, numbered 505, will be an oral presentation titled "Imdusiran (AB-729) administered every 8 weeks for 24 weeks followed by the immunotherapeutic VTP-300 maintains lower HBV surface antigen levels in NA-suppressed CHB subjects than 24 weeks of imdusiran alone." To be presented by Prof. Kosh Agarwal on June 6, 2024, this research concludes that repeated dosing of imdusiran for 24 weeks followed by VTP-300 is well-tolerated and helps in maintaining lower HBsAg levels compared to a placebo in subjects at the end of treatment and at a 60-week follow-up. Additionally, more subjects who received VTP-300 were able to discontinue NA-therapy and all remained off therapy. Further data on on-treatment, follow-up, and NA discontinuation will be presented.

The abstracts are accessible on the EASL Congress 2024 website, and the posters will be available to conference attendees starting June 5, 2024. The presentations will subsequently be available on Arbutus’ website.

Imdusiran (AB-729) is an RNA interference (RNAi) therapeutic designed to reduce all HBV viral proteins and antigens, including hepatitis B surface antigen (HBsAg), which is considered essential for reactivating the patient's immune system to respond to the virus. Imdusiran employs Arbutus’ novel covalently conjugated N-Acetylgalactosamine (GalNAc) delivery technology for subcutaneous administration. Clinical data to date indicates that both single and multiple doses of imdusiran are generally safe and well-tolerated, leading to significant reductions in HBsAg and hepatitis B DNA. Imdusiran is currently undergoing multiple Phase 2a clinical trials.

Hepatitis B is a potentially fatal liver infection caused by the hepatitis B virus (HBV), which can lead to chronic infection, significantly increasing the risk of death from cirrhosis and liver cancer. Chronic HBV infection remains a critical unmet medical need, with the World Health Organization estimating over 290 million people globally affected by chronic HBV. In the United States, approximately 2.4 million people suffer from chronic HBV, with around 820,000 annual deaths attributed to complications from chronic HBV despite effective vaccines and treatment options.

Arbutus Biopharma Corporation aims to develop innovative therapeutics with distinct mechanisms of action to provide a functional cure for patients with chronic HBV. Their pipeline includes the RNAi therapeutic imdusiran (AB-729) and an oral PD-L1 inhibitor, AB-101, with imdusiran currently in Phase 2a clinical trials and AB-101 in a Phase 1a/1b trial.