Arbutus Biopharma Presents Promising Hepatitis B Treatment Data
Imdusiran combined with VTP-300 and nivolumab shows promise for achieving functional cures in chronic hepatitis B patients.
Key Findings from EASL Congress 2025
Arbutus Biopharma Corporation has unveiled encouraging findings at the EASL Congress 2025. Data from a late-breaker presentation revealed that their treatment, combining imdusiran—an RNA interference (RNAi) therapeutic—with VTP-300 and low-dose nivolumab, has resulted in functional cures for some patients suffering from chronic hepatitis B (cHBV). In a Phase 2a clinical trial, three out of the patients treated with nivolumab experienced loss of hepatitis B surface antigen (HBsAg) and seroconversion, leading to a functional cure rate of 15.3% in this subgroup. Notably, most patients maintained reduced HBsAg levels following treatment. Imdusiran demonstrated a favorable safety profile, with no serious adverse events or immune-related complications reported. Additionally, data from a Phase 1 trial on AB-101, an oral PD-L1 inhibitor, suggested a good safety and tolerability profile in cHBV patients. These insights could represent significant advancements in addressing chronic HBV, a major global health issue.
Potential Benefits
- The combination of imdusiran with VTP-300 and low-dose nivolumab indicates potential as a breakthrough treatment for chronic hepatitis B, demonstrating a functional cure in patients.
- Phase 1a/1b clinical trial results for AB-101 show it is generally well-tolerated, exhibiting high receptor occupancy and no liver dysfunction.
- Arbutus’s presentation of multiple posters at a prominent congress enhances its profile and credibility within the biopharmaceutical sector.
Challenges Ahead
- The reported functional cure rate of 15.3% may raise questions regarding the efficacy of the treatment for a broader patient population.
- Success appears contingent on specific patient criteria, such as having low baseline HBsAg levels (around 1000 IU/mL), which may limit wider application of the treatment.
- Ongoing legal disputes concerning intellectual property with major competitors could distract the company from its core operations and resource allocation.
Frequently Asked Questions
What is imdusiran, and how does it relate to hepatitis B treatment?
Imdusiran is an RNAi therapeutic designed to decrease HBV viral proteins while stimulating the immune response in chronic hepatitis B patients.
What were the clinical trials’ findings for imdusiran?
Clinical trials indicated that combining imdusiran with VTP-300 and low-dose nivolumab led to functional cures in certain chronic hepatitis B patients, marked by reduced HBsAg levels.
What safety profile does AB-101 demonstrate?
AB-101, an oral PD-L1 inhibitor, was generally found to be safe and well-tolerated, with no immune-related adverse events or liver dysfunction indicated in the trials.
What are the key results from the EASL Congress 2025?
Patients receiving treatment with imdusiran and VTP-300 showed an increased likelihood of achieving HBsAg loss and maintaining lower levels over time.
Why is chronic hepatitis B considered a global health issue?
Chronic hepatitis B presents a substantial health challenge, affecting over 250 million people worldwide and leading to severe complications like cirrhosis and liver cancer, contributing to high mortality rates.
Insider Trading Activity
In the past six months, insiders at $ABUS have engaged in trading activities, noting four sales and no purchases of shares.
- MICHAEL J. MCELHAUGH (Interim President & CEO) sold 23,790 shares for an estimated $78,102.
- DAVID C. HASTINGS (Chief Financial Officer) sold 22,183 shares for an estimated $72,826.
- KAREN SIMS (Chief Medical Officer) sold 19,348 shares for an estimated $63,519.
- J. CHRISTOPHER NAFTZGER (General Counsel and CCO) sold 11,333 shares for an estimated $37,206.
Hedge Fund Activity
Over the most recent quarter, 69 institutional investors bought shares of $ABUS, while 59 reduced their holdings.
- FOURWORLD CAPITAL MANAGEMENT LLC removed 1,745,817 shares (-58.7%) for an estimated $5,708,821.
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Full Release
Data highlighted in late-breaker poster presentation shows that imdusiran achieves functional cure in chronic hepatitis B (cHBV) patients when combined with VTP-300 and low dose nivolumab.
AB-101, an oral PD-L1 inhibitor, has shown to be generally safe and well-tolerated with evidence of high receptor occupancy and no liver dysfunction in cHBV patients.
WARMINSTER, Pa., May 7, 2025 (GLOBE NEWSWIRE) — Arbutus Biopharma Corporation (Nasdaq: ABUS), a clinical-stage biopharmaceutical company focused on infectious diseases, announced the presentation of five posters, including one late-breaker, at the European Association for the Study of the Liver (EASL) Congress 2025.
The late-breaker poster presented key data from the Phase 2a clinical trial (IM-PROVE II, AB-729-202), which evaluated stable nucleos(t)ide analogue (NA) therapy alongside imdusiran (60mg every 8 weeks) for 24 weeks combined with either Barinthus Biotherapeutic’s T-cell stimulating immunotherapeutic VTP-300 without nivolumab (Group A, n=20) or with low-dose nivolumab (Group C, n=22; 13 received nivolumab).
# Promising Results in Treatment of Chronic Hepatitis B from IM-PROVE II Trial
### Key Findings from the IM-PROVE II Trial
– **Chronic Hepatitis B Patients Achieve HBsAg Loss**: In Group C, three patients receiving nivolumab experienced loss of Hepatitis B surface antigen (HBsAg), indicating a positive response to treatment. All these patients had a baseline HBsAg IU level below the limit of quantitation (lloq) at the end of the trial.
– **Functional Cure Rates**: Of Group C participants with a baseline HBsAg of less than 1000 IU/mL who received nivolumab, 25% (2 out of 8) achieved a functional cure. Overall, the functional cure rate for this group was recorded at 15.3% (2 out of 13).
– **Durable Responses to Treatment**: Most participants treated with imdusiran showed consistently lower HBsAg levels compared to pre-treatment levels during the follow-up period.
– **Therapeutic Benefits**: Compared to the placebo group (Group B), more patients in the imdusiran and VTP-300 group (Group A) were able to discontinue nucleos(t)ide analogue (NA) therapy, despite not achieving a functional cure.
– **Safety Profile**: The combination treatment of imdusiran, VTP-300, and low-dose nivolumab presented a favorable safety profile, with no serious adverse events, deaths, or discontinuations noted. There were also no immune-related adverse events, including thyroid issues.
### Insights from Dr. Grace Lai-Hung Wong
Dr. Grace Lai-Hung Wong, a professor at The Chinese University of Hong Kong, highlighted the trial’s findings: “We observed that reducing HBsAg levels with imdusiran before adding other therapies promoted HBV-specific immune responses. The data indicates that introducing low doses of nivolumab alongside imdusiran and VTP-300 in chronic hepatitis B patients is well tolerated and enhances the likelihood of HBsAg loss and functional cure.”
### Background on HBsAg Levels and Patient Outcomes
It has been reported that patients with HBsAg levels below 1000 IU/mL comprise a significant proportion of the chronic Hepatitis B population. Across all Phase 2a clinical trials involving imdusiran, Arbutus has confirmed a total of eight patients have attained functional cures, notably, seven of whom had baseline HBsAg levels under 1000 IU/mL.
### Additional Findings on AB-101
At the EASL conference, Arbutus also presented data on AB-101, derived from its Phase 1a/1b clinical trial. The findings showed that daily dosing of 10 mg for 28 days was well tolerated by chronic Hepatitis B patients, with receptor occupancy comparable to that of healthy volunteers receiving similar doses. Importantly, no immune-related adverse events or liver dysfunction were recorded during the study.
### Trial Methodology: IM-PROVE II Overview
The IM-PROVE II Phase 2a trial initially enrolled 40 non-cirrhotic, virally suppressed chronic Hepatitis B patients on stable NA therapy. Participants were given imdusiran (60 mg every 8 weeks) for 24 weeks, followed by randomization to receive either VTP-300 or placebo at Weeks 26 and 30. Those who met specific criteria at Week 48 were eligible to discontinue NA therapy, while others continued for an additional 24 weeks.
An amendment to the trial added a cohort of 20 patients treated with imdusiran alongside NA therapy for 24 weeks, then randomized to receive VTP-300 combined with up to two low doses of nivolumab.
### About Imdusiran (AB-729)
Imdusiran is an RNA interference therapeutic targeting all HBV proteins and antigens. This is pivotal for immune system reawakening against the virus. Arbutus’ innovative delivery technology allows for subcutaneous administration, with encouraging data showing safe and effective treatment outcomes in patients with chronic Hepatitis B.
### About AB-101
AB-101 is an oral PD-L1 inhibitor designed to optimize immune checkpoint blockade while reducing systemic safety concerns often associated with similar therapies. Initial results from Arbutus’ ongoing trial indicate that AB-101 is well tolerated and promotes significant receptor occupancy.
### Understanding HBV
Hepatitis B is a serious liver infection caused by the hepatitis B virus (HBV), which can lead to chronic infection. This chronic state significantly raises the risk of cirrhosis and liver cancer, addressing an urgent medical need. The World Health Organization estimates over 250 million people live with chronic HBV globally, including about 2 million in the United States. Annually, approximately 1.1 million deaths occur due to complications related to chronic HBV.
### About Arbutus Biopharma Corporation
Arbutus Biopharma Corporation (Nasdaq: ABUS) is a biopharmaceutical firm focusing on infectious diseases. The company is advancing therapies for chronic Hepatitis B, including imdusiran and the oral PD-1 inhibitor, AB-101. For more information, visit www.arbutusbio.com.
### Forward-Looking Statements
This press release contains forward-looking statements, as defined by relevant securities regulations. These statements involve risks and uncertainties that could materially affect actual outcomes.# Arbutus Biopharma Discusses Risks and Prospects for HBV Treatments
In a recent press release, Arbutus Biopharma provided insights into its potential for a functional cure for Hepatitis B Virus (HBV) and the company’s product candidates’ prospects in clinical trials. However, they emphasized the numerous assumptions underlying these forward-looking statements. These include considerations related to the effectiveness and timely execution of clinical trials, the utility of resulting data, and the anticipated approvals from regulatory bodies.
Arbutus’s management asserts that its assumptions are reasonable, yet various uncertainties could significantly influence outcomes. Known risks include the possibility that ongoing or planned clinical trials may incur higher costs or delays, potentially hindering initiation or completion. Furthermore, there is no guarantee that the trials will yield favorable outcomes warranting further product development. The company might also alter its strategic focus regarding product candidates based on these evolving circumstances.
Among the specific risks is the potential for regulatory hurdles that may impede the clinical development of Arbutus’ treatments. Additionally, economic and market conditions could deteriorate, necessitating further adjustments to their strategic approach.
For a more in-depth analysis of the risks and uncertainties facing Arbutus, stakeholders are encouraged to refer to the company’s Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, and other continuous and periodic filings. These documents are accessible on both
www.sedar.com
and
www.sec.gov
.
All forward-looking statements in the release are accompanied by this cautionary message, which highlights that Arbutus disclaims any obligation to revise or update these statements unless mandated by law.
