Arbutus Reports First Quarter 2026 Financial Results and Provides Corporate Update

Arbutus Reports Strong Q1 2026, Secures Moderna Settlement, and Imdusiran Fast Track

Arbutus Biopharma reported strong first-quarter 2026 financial results, significantly boosted by a major litigation settlement. The company, along with its licensee Genevant Sciences, settled all global patent infringement litigation with Moderna, securing an upfront payment of $950 million, with Arbutus expecting to receive an estimated $178.7 million. Concurrently, the U.S. FDA granted Fast Track designation to imdusiran for chronic hepatitis B, aiming to expedite its development and review. For Q1 2026, Arbutus posted total revenue of $179.1 million and a net income of $169.7 million, strengthening its financial position with $95.2 million in cash, cash equivalents, and marketable securities as of March 31, 2026.

• Arbutus and its exclusive licensee, Genevant Sciences, reached a comprehensive settlement agreement with Moderna, resolving all global patent infringement litigation and patent revocation proceedings. This landmark agreement includes an upfront payment of $950 million in July 2026, with a potential additional $1.3 billion contingent on an appellate ruling. Arbutus anticipates receiving an estimated $178.7 million from the non-contingent settlement payment.
• The U.S. Food and Drug Administration (FDA) granted Fast Track designation for imdusiran for the treatment of chronic hepatitis B. This designation is intended to facilitate development and accelerate FDA review of investigational therapies for serious conditions with unmet medical needs. Benefits include earlier and more frequent meetings with the FDA and potential eligibility for rolling review, Accelerated Approval, or Priority Review. Imdusiran is an RNAi therapeutic designed to reduce hepatitis B viral proteins and antigens.
• Arbutus reported robust financial performance for the first quarter of 2026, with total revenue soaring to $179.1 million, a substantial increase from $1.8 million in the same period of 2025, primarily due to license revenue from the Moderna settlement. The company achieved a net income of $169.7 million, or $0.87 per diluted common share, a significant improvement from a net loss in Q1 2025. As of March 31, 2026, Arbutus maintained a strong financial position with $95.2 million in cash, cash equivalents, and marketable securities.

Addressing Unmet Needs in Chronic Hepatitis B Treatment

Current treatment approaches for chronic hepatitis B face significant limitations that prevent achieving optimal patient outcomes. Despite decades of therapeutic advances, the inability to completely eliminate the virus and achieve functional cure remains the predominant challenge. These limitations necessitate lifelong treatment for most patients and highlight substantial unmet medical needs.

• Inability to eliminate viral reservoirs - Current first-line therapeutics including nucleos(t)ide analogues and interferons cannot clear hepatitis B virus covalently closed circular DNA (cccDNA), requiring the vast majority of patients to take long-term or lifelong medication

• Limited functional cure rates - Efficacy in attaining serological responses, particularly functional cure defined as loss of serum hepatitis B surface antigen (HBsAg), remains very limited with current therapeutic approaches

• Drug resistance emergence - Development of resistance to nucleos(t)ide analogues poses ongoing challenges, with lamivudine resistance occurring in approximately 60% of patients during the first 3 years of therapy, while entecavir resistance reaches approximately 15% at 3 years in patients with prior lamivudine resistance

• Suboptimal interferon responses - Pegylated interferon therapy demonstrates lack of effectiveness in a large proportion of patients and is associated with significant adverse effects, limiting its clinical utility

• Challenges in treatment discontinuation - Difficulty in identifying patients who can successfully withdraw from antiviral therapy despite achieving long-term virological and biochemical responses, with frequent viral rebound upon treatment cessation

• Impaired host immune responses - The persistent, self-replenishing nature of the viral genome combined with compromised host immune responses makes chronic HBV infection particularly difficult to cure, even with combination therapeutic strategies

Imdusiran's Promising Phase 2a Outcomes in cHBV

Recent clinical trials in chronic hepatitis B have demonstrated significant advances across multiple therapeutic approaches. The GST-HG141 phase II trial evaluated a novel capsid assembly modulator in patients with low-level viremia on nucleos(t)ide analog therapy. This randomized, double-blind, placebo-controlled study enrolled 90 patients across ten research centers in China, comparing low-dose (50 mg BID) and high-dose (100 mg BID) GST-HG141 against placebo for 24 weeks. The primary endpoint of achieving HBV DNA <20 IU/mL at week 24 was met by 84.0% of low-dose and 81.5% of high-dose patients versus 32.1% receiving placebo (p<0.05). Notably, pregenomic RNA levels declined by an average of 1.7 log copies/mL, with 60% and 55% of patients in the treatment groups achieving undetectable levels compared to 9.5% with placebo. The safety profile was favorable with comparable adverse events across all groups.

The PENGUIN study (NCT04667104) investigated combination RNA interference therapy with JNJ-3989 ± bersacapavir plus pegylated interferon alpha-2a in an open-label, single-arm phase IIa design. Among 48 enrolled patients, 64.6% achieved the primary endpoint of ≥2 log IU/mL HBsAg reduction from baseline at week 24. Mean HBsAg reductions were -1.43 logIU/mL at week 12 and -2.18 logIU/mL at week 24, though this declined to -0.71 logIU/mL at follow-up week 48. Importantly, 31.3% of patients met nucleos(t)ide analog stopping criteria at week 24, with 73.3% remaining off treatment by follow-up week 48. One patient achieved functional cure at follow-up week 48, demonstrating the potential for sustained virological control.

Nucleos(t)ide analog development continued with the phase III trial of pradefovir mesylate, a liver-targeting prodrug of adefovir. This non-inferiority study randomized 908 patients 2:1 to receive pradefovir 45 mg daily versus tenofovir disoproxil fumarate 300 mg daily. At week 48, viral suppression rates (HBV DNA <29 IU/mL) demonstrated non-inferiority for both HBeAg-positive and HBeAg-negative patients. By week 96, HBeAg-positive patients showed significantly greater HBsAg decline (≥1 log10 IU/mL) with pradefovir compared to tenofovir (39.3% vs. 29.9%). The safety profile favored pradefovir, with significantly fewer drug-related adverse events (58.6% vs. 71.9%) and improved bone and renal safety parameters, addressing key limitations of previous nucleotide analogs.

The Evolving Treatment Landscape for Chronic Hepatitis B

The treatment landscape for chronic hepatitis B has undergone significant evolution over the past five years, with a fundamental shift toward functional cure as the primary treatment goal. Functional cure, defined as HBsAg loss sustained for 24 weeks after therapy discontinuation, has replaced viral suppression as the long-term objective for chronic hepatitis B management. This paradigm shift reflects growing recognition that current nucleos(t)ide analogues, while effective at suppressing viral replication and improving liver pathology, cannot eliminate HBV covalently closed circular DNA (cccDNA) and rarely achieve sustained off-treatment suppression. Patient preference studies have reinforced this direction, with high efficacy and functional cure scenarios driving 57% of treatment decisions among chronic hepatitis B patients.

Therapeutic strategies have evolved to encompass three distinct categories: agents that reduce viral replication, those that reduce antigen load, and immunotherapies. Recent clinical evidence demonstrates that combining nucleos(t)ide analogues with immunotherapy can reduce quantitative HBsAg levels and induce HBsAg loss in selected patients, particularly those with low baseline qHBsAg levels. Novel approaches include small interfering RNA, antisense oligonucleotides, and nucleic acid polymers, which in combination with pegylated interferon and nucleos(t)ide analogues may achieve HBsAg loss rates up to 40% sustained for more than 24 weeks after treatment completion. Additionally, genetic predictors of treatment response have emerged, with the rs7519753 C allele identified as significantly associated with HBsAg loss following pegylated interferon-α treatment through enhanced hepatic TP53BP2 expression.

The comparative efficacy landscape has been refined through real-world evidence comparing tenofovir alafenamide (TAF) with established nucleos(t)ide analogues. TAF has demonstrated superior viral suppression rates, with 93% of patients achieving HBV DNA ≤20 IU/mL compared to 86% with tenofovir disoproxil fumarate or entecavir at 24 months, alongside higher rates of ALT normalization and improved renal safety profiles. Treatment discontinuation strategies have also evolved, with EASL 2017 guidelines enabling cessation in well-selected patients, though careful monitoring remains essential as 50% of patients maintain virological suppression without therapy reinitiation over 12 months. Novel therapeutic targets continue to emerge, including HBV RNase H inhibitors and mTOR pathway modulators, while cccDNA transcriptional silencing represents a promising strategy for achieving the ultimate goal of HBV eradication rather than mere suppression.

RNAi's Strategic Ascent: Arbutus's Settlement and CHB Focus

Arbutus Biopharma's recent financial report, significantly bolstered by a substantial patent infringement settlement with Moderna, marks a pivotal moment for the company and underscores the escalating value of intellectual property in the burgeoning field of nucleic acid therapeutics. The $950 million upfront payment, with a significant portion flowing to Arbutus, provides a robust financial foundation, enabling the company to accelerate its research and development efforts and pursue strategic growth initiatives without immediate reliance on dilutive financing. This settlement, likely centered on RNA interference (RNAi) delivery technologies, validates the critical importance of proprietary platforms in developing advanced genetic medicines.

Concurrently, the U.S. FDA's Fast Track designation for imdusiran in chronic hepatitis B (CHB) signals a potential expedited pathway for a novel therapeutic in an area with persistent unmet needs. While existing treatments for CHB, such as pegylated interferon and nucleoside analogues, have improved patient outcomes, challenges like drug resistance remain. RNAi therapeutics, which function by directly modulating gene expression, have demonstrated transformative potential in other chronic conditions, including hereditary amyloidosis and hypertension, by offering sustained disease control with infrequent dosing. Imdusiran, as an RNAi agent, could offer a similar paradigm shift for CHB patients.

However, the path forward is not without its considerations. Despite the Fast Track status, imdusiran must still navigate rigorous clinical trials to definitively establish its efficacy and safety profile. The broader RNAi field, while rapidly advancing, continues to grapple with challenges such as potential off-target effects, dose-dependent toxicities, and efficient tissue-specific delivery. Furthermore, the CHB market is competitive, necessitating that imdusiran demonstrate a clear advantage over established therapies to secure significant market share. Arbutus's strategic success will hinge on its ability to leverage its newfound financial strength and validated intellectual property to overcome these development hurdles, bringing innovative RNAi solutions to patients and further solidifying the role of genetic medicines in modern pharmacology.