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Item 2. Management’s Discussion and Analysis

2026-05-13 compared with 2025-11-13 · 176 added, 213 removed, 273 unchanged (59% of the section changed)

MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

You should read the following discussion and analysis by our management of our financial position and results of operations in conjunction with our audited consolidated financial statements and related notes thereto included as part of our Annual Report on Form 10-K for the year ended December 31, 2024 and our unaudited condensed consolidated financial statements for the three and nine months ended September 30, 2025.

You should read the following discussion and analysis by our management of our financial position and results of operations in conjunction with our audited consolidated financial statements and related notes thereto included as part of our Annual Report on Form 10-K for the year ended December 31, 2025 and our unaudited condensed consolidated financial statements for the three months ended March 31, 2026.

Our consolidated financial statements have been prepared in accordance with United States generally accepted accounting principles and are presented in U.S.

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• our strategy, future operations, preclinical studies, clinical trials, and prospects;

• our beliefs, plans and expectations regarding our patent infringement lawsuits against Moderna and Pfizer/BioNTech;

• our beliefs, plans and expectations regarding our patent infringement lawsuit against Pfizer/BioNTech, and the expected timing thereof;

• our beliefs, plans and expectations regarding Moderna’s limited appeal following the settlement of our patent infringement litigation, the noncontingent lump sum payment and the contingent lump sum payment included in our settlement with Moderna, and the expected timing thereof;

• our evaluation of a potential return of capital to our shareholders in connection with the settlement of our patent infringement lawsuits against Moderna, and the expected timing thereof;

• our beliefs, plans and expectations regarding our patent infringement lawsuit against the United States, and the expected timing thereof;

• the potential for our product candidates to achieve their desired or anticipated outcomes;

• the expected cost, timing and results of our clinical development plans and clinical trials, including our clinical collaborations with third parties;

• the expected cost, timing and results of our clinical development plans and clinical trials, including clinical collaborations with third parties;

• the development and commercialization of a therapy for chronic hepatitis B infection, a disease of the liver caused by the hepatitis B virus;

• our aim to prevent complications of disease progression, to decrease hepatitis B virus burden by minimizing patient stigma and to address the need for finite and more efficacious hepatitis B virus treatments that further improve long-term outcomes and reduce associated healthcare costs;

• our aim to prevent complications of hepatitis B virus disease progression, to decrease hepatitis B virus burden by minimizing patient stigma and to address the need for finite and more efficacious hepatitis B virus treatments that further improve long-term outcomes and reduce associated healthcare costs;

• the potential of our product candidates to improve upon the standard of care to treat hepatitis B infection and provide clinical benefits to hepatitis B patients;

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We are currently developing imdusiran (AB-729), our proprietary, GalNAc-conjugated, subcutaneously-delivered ribonucleic acid interference (RNAi) therapeutic, and AB-101, our proprietary oral PD-L1 inhibitor, for the treatment of chronic hepatitis B (cHBV).

We continue to protect and defend our intellectual property, which is the subject of our ongoing lawsuits against Moderna Therapeutics, Inc.

(Moderna) and against Pfizer Inc.

We continue to protect and defend our intellectual property, which is the subject of our ongoing lawsuit against Pfizer Inc.

and BioNTech SE (collectively, Pfizer/BioNTech) for their use of our patented lipid nanoparticle (LNP) technology in their COVID-19 messenger ribonucleic acid interference (mRNA)-LNP vaccines.

With respect to the Moderna lawsuit in the United States, fact discovery, expert discovery and summary judgment briefing have been completed, and a trial date has been set for March 2026.

In March 2025, we, along with Genevant Sciences GmbH and/or its affiliates (collectively, Genevant), filed five international lawsuits against Moderna in connection with the use of our LNP technology in Moderna’s COVID-19 mRNA-LNP vaccines and, in the Unified Patent Court, also other Moderna products that use the same LNP technology, including Moderna’s respiratory syncytial virus (RSV) vaccines.

Public oral hearings for the two cases in the Unified Patent Court are scheduled for May 2026, and the trial in the Canadian case is set to begin in September 2027.

With respect to the Pfizer/BioNTech lawsuit, the court issued a claim construction ruling in September 2025, which construed the disputed claim terms in a manner we generally consider to be favorable.

During 2024, we streamlined the organization to focus our efforts on advancing the clinical development of imdusiran and AB-101, and therefore ceased all discovery efforts, halted preparations for a potential IM-PROVE III clinical trial and reduced our workforce by 40%.

In the first quarter of 2025, we announced the appointment of five new members of our Board of Directors (our Board) to replace all of the former directors, as well as the appointment of a new President, Chief Executive Officer and Chairperson of our Board and a new Chief Financial Officer.

Additionally, our Board took action to reduce our workforce by an additional 57%.

Our Board also decided to exit our corporate headquarters in Warminster, Pennsylvania and to discontinue in-house scientific research.

In connection with these actions, we incurred a one-time restructuring charge in the first quarter of 2025 of $12.4 million.

With these organizational changes and our ongoing cost management efforts, we expect to significantly reduce our net cash burn in 2025 when compared to 2024.

In June 2025, we launched a new Scientific Advisory Board (SAB) consisting of globally-recognized leaders in the treatment of cHBV with extensive experience in late-stage clinical trials.

SAB members are advising us on the strategic evaluation of our cHBV pipeline.

In August 2025, we announced changes to our Board.

Effective August 4, 2025, Anuj Hasija resigned from our Board due to his transition to a full-time executive role at another company that precludes his participation on our Board and other boards of directors.

Roger Sawhney was appointed to the vacant seat on our Board, effective August 4, 2025.

Sawhney was also appointed as a member of our Board’s Audit Committee and Corporate Governance and Nominating Committee.

The court issued a claim construction ruling in September 2025, which construed the disputed claim terms in a manner we generally consider to be favorable.

The parties are awaiting further scheduling in the litigation.

On March 3, 2026, we, along with Genevant Sciences GmbH and, solely for specified purposes, its parent company Genevant Sciences Ltd.

(collectively, Genevant, a related party), entered into a settlement agreement (the Moderna Settlement Agreement) with Moderna Inc.

and ModernaTX, Inc.

(together, Moderna) to resolve all patent infringement litigation and patent revocation proceedings involving Moderna and its affiliates pending in the United States and internationally (the Moderna LNP Litigation).

Under the terms of the Moderna Settlement Agreement, Moderna will make an aggregate $950.0 million noncontingent lump sum payment (the Noncontingent Settlement Payment) to us and Genevant on or before July 8, 2026.

In addition, Moderna is obligated to pay us and Genevant an additional aggregate contingent lump sum payment of $1.3 billion (the Contingent Settlement Payment) upon a ruling that is favorable to us and Genevant in a limited appeal related to 28 U.S.C.

§1498 (§1498) that Moderna filed, as allowed under the Moderna Settlement Agreement (the Moderna §1498 Appeal).

Under our license with Genevant, we are entitled to receive, after deduction of litigation costs, 20% of the Noncontingent Settlement Payment.

We currently expect to receive an estimated $178.7 million of the Noncontingent Settlement Payment, which includes reimbursement of our litigation costs.

In addition, as of March 31, 2026, we owned approximately 16% of the outstanding common equity of Genevant.

We are currently evaluating a return of capital to our shareholders in the third quarter of calendar year 2026, following the receipt of our portion of the Noncontingent Settlement Payment.

In April 2026, the U.S.

Food and Drug Administration (FDA) granted Fast Track designation for imdusiran for the treatment of cHBV.

The FDA’s Fast Track program is designed to facilitate the development and expedite the review of investigational therapies to treat serious conditions with unmet medical need.

Our strategy is focused on maximizing opportunities for our cHBV development programs and, through our exclusive license with Genevant, our in-house developed LNP technology.

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Without this crucial technology, the mRNA would quickly degrade in the body and be ineffective.

We remain committed to taking all legal actions necessary to defend and protect our intellectual property.

With respect to the Moderna lawsuit in the United States, the court provided its claim construction ruling in April 2024 in which it construed the disputed claim terms and agreed with our position on most of the disputed claim terms.

Fact discovery, expert discovery and summary judgment briefing have been completed, and a trial date has been set for March 2026.

In March 2025, we, along with Genevant, filed five international lawsuits against Moderna in connection with Moderna’s use of our LNP technology in Moderna’s COVID-19 mRNA-LNP vaccines and, in the Unified Patent Court, also other Moderna products that use the same LNP technology, including Moderna’s RSV vaccines.

Public oral hearings for the two cases in the Unified Patent Court are scheduled for May 2026, and the trial in the Canadian case is set to begin in September 2027.

We continue to protect and defend our intellectual property, which is the subject of our ongoing lawsuit against Pfizer/BioNTech for their use of our patented LNP technology in their COVID-19 mRNA-LNP vaccines.

cHBV programs

Our HBV strategy has been to develop a functional cure for patients with cHBV infection with imdusiran as a potential cornerstone in a combination therapy.

Development to date has emphasized a combination of compounds that can suppress hepatitis B virus deoxyribonucleic acid (HBV DNA) replication, hepatitis B virus RNA (HBV RNA) replication, and hepatitis B surface antigen (HBsAg) expression, as well as boost patients’ HBV-specific immune response, which together could address the most important elements to achieving a functional cure.

Our hepatitis B (HBV) strategy has been to develop a functional cure for patients with cHBV infection with imdusiran as a potential cornerstone in a combination therapy.

Development to date has emphasized a combination of compounds that can suppress hepatitis B virus deoxyribonucleic acid (HBV DNA) replication, hepatitis B virus RNA (HBV RNA) transcription, and hepatitis B surface antigen (HBsAg) and other viral protein expression, as well as boost patients’ HBV-specific immune response, which together could address the most important elements to achieving a functional cure.

Functional cure is defined as sustained HBsAg seroclearance and HBV DNA less than the lower limit of quantification (<LLOQ) after 24 weeks off treatment, with or without anti-hepatitis B surface antibodies (anti-HBs).

A functional cure for patients with cHBV could prevent complications of disease progression, decrease HBV burden by minimizing patient stigma and address the need for finite and more efficacious HBV treatments that further improve long-term outcomes and reduce associated healthcare costs.

Our current ongoing evaluation of our HBV strategy also includes analysis of imdusiran’s potential to suppress HBV DNA and HBV RNA replication and HBsAg expression, without any immunotherapeutics.

A functional cure for patients with cHBV could prevent complications of HBV disease progression, decrease HBV burden by minimizing patient stigma and address the need for finite and more efficacious HBV treatments that further improve long-term outcomes and reduce associated healthcare costs.

Our current ongoing evaluation of our HBV strategy also includes analysis of imdusiran’s potential to suppress HBV DNA replication and HBV RNA and HBsAg expression, without any immunotherapeutics.

We are also continuing to evaluate and refine potential Phase 2b clinical trial designs for imdusiran.

Our HBV product pipeline includes the following:

• Imdusiran (AB-729) is our proprietary, GalNAc-conjugated, subcutaneously-delivered RNAi therapeutic product candidate that suppresses all HBV antigens, including HBsAg, which is thought to be a key prerequisite to enable reawakening of a patient’s immune system to respond to HBV.

• Imdusiran (AB-729) is our proprietary, GalNAc-conjugated, subcutaneously-delivered RNAi therapeutic product candidate that suppresses all HBV antigens, including HBsAg, which is thought to be a key prerequisite to enable potentiation of a patient’s immune system to respond to HBV.

Over 200 patients with cHBV infection have been dosed with imdusiran in Phase 1 and Phase 2a clinical trials.

Clinical data generated thus far has shown imdusiran provides meaningful reductions in HBsAg, HBV DNA and HBV RNA, and leads to functional cure in some patients, while being generally safe and well-tolerated.

Clinical data generated thus far has shown imdusiran provides meaningful reductions in HBsAg and other viral proteins, HBV DNA and HBV RNA, and leads to functional cure in some patients, while being generally safe and well-tolerated.

Benefits were observed in patients across all evaluated HBV genotypes (A to E).

To date, eight patients achieved functional cure, off all treatment, in combination therapy that includes imdusiran, including two patients who did not receive any pegylated interferon alfa-2a (IFN) as part of the combination therapy.

An additional 40 patients across our Phase 2a clinical trials were able to remain off NA therapy for at least 48 weeks after discontinuing NA therapy following treatment with imdusiran (46% (48/105) of all Phase 2a patients achieved functional cure or remained off NA therapy after discontinuing NA therapy following treatment with imdusiran).

Of the 18 patients who consented to long-term follow-up, which includes all functionally cured patients and 10 patients who discontinued and remained off NA therapy for 48 weeks, 94% continue to remain off NA therapy for between 58 and 109 weeks.

One functionally cured patient seroreverted but remains virally suppressed and off NA therapy.

• AB-101 is our proprietary oral PD-L1 inhibitor that has the potential to reawaken patients’ HBV-specific immune response by inhibiting PD-L1.

In the Phase 1 and Phase 2a clinical trials, eight patients achieved functional cure, off all treatment, in combination therapy that includes imdusiran, including two patients who did not receive any pegylated interferon alfa-2a (IFN) as part of the combination therapy.

An additional 41 patients across our Phase 2a clinical trials were able to remain off nucleos(t)ide analogue (NA) therapy for at least 48 weeks after discontinuing NA therapy during their Phase 2a clinical trials.

A total of 47% (49/105) of all Phase 2a patients achieved functional cure or remained off NA therapy after discontinuing NA therapy during their Phase 2a clinical trials.

Of the 18 patients who are currently being followed long-term (which includes the eight functionally cured patients described above and 10 patients who discontinued and remained off NA therapy), one patient who discontinued NA therapy achieved functional cure during the long-term follow-up period, and 89% of the 18 patients continue to remain off NA therapy for between 82 and 134 weeks.

Two of the original eight functionally cured patients seroreverted during long-term follow-up, but remain virally suppressed and off NA therapy.

Furthermore, among an additional 11 patients with available data who discontinued NA therapy during their Phase 2a clinical trials, but were subsequently discontinued early from long-term follow-up, one patient achieved functional cure and two restarted NA therapy.

To date, a total of 10 patients have achieved functional cure during our Phase 2a clinical trials and long-term follow-up.

• AB-101 is our proprietary oral PD-L1 inhibitor that has the potential to activate patients’ HBV-specific immune response by inhibiting PD-L1.

AB-101 is currently in a Phase 1a/1b clinical trial (AB-101-001) evaluating the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of single- and multiple-ascending oral doses in healthy subjects and patients with cHBV infection.

The data from healthy subjects in Parts 1 and 2 and cHBV patients to date in Part 3 of this clinical trial have showed that AB-101 was generally well-tolerated with evidence of high receptor occupancy.

The data from healthy subjects in Parts 1 and 2 and cHBV patients in Part 3 of this clinical trial have shown that AB-101 was generally well-tolerated with evidence of high receptor occupancy.

To help position imdusiran as a potential cornerstone in a combination therapy, we fully enrolled two Phase 2a clinical trials that combined imdusiran with other agents.

The intent of these trials was to initially lower HBsAg levels with imdusiran and then administer a complementary agent, an immune modulator or a therapeutic vaccine, to further lower HBsAg levels and promote anti-HBV immunity.

Our belief in these trials was that if we can lower HBsAg and promote immunity, we may achieve sustained HBsAg seroclearance and HBV DNA <LLOQ, potentially leading to a functional cure in many patients with cHBV.

We believe that if we can lower HBsAg and other viral antigens and promote immunity, we may achieve sustained HBsAg seroclearance and HBV DNA <LLOQ, potentially leading to a functional cure in patients with cHBV.

Currently, patients with cHBV have limited treatment options - either NA therapy, which requires lifelong treatment, or a finite duration of IFN, which is poorly tolerated and has serious complications and side effects.

We believe patients can see significant benefits even without functional cure if they are well enough to be able to discontinue NA therapy and maintain viral suppression.

To date, a total of eight patients with cHBV achieved functional cure following treatment with imdusiran and NA therapy in combination with either IFN or with low dose nivolumab plus an immunotherapeutic, with seven of the eight patients continuing to sustain functional cure for periods ranging between 58 to 109 weeks.

Seven of the eight total patients who achieved functional cure at the 60mg dose of imdusiran had HBsAg less than 1000 IU/mL at baseline.

We believe patients can see significant benefits with imdusiran even without functional cure if they are well enough to be able to discontinue NA therapy and maintain viral suppression.

In the Phase 2a clinical trials, eight patients with cHBV achieved functional cure following treatment with imdusiran and NA therapy in combination with either IFN or with low dose nivolumab plus an immunotherapeutic.

Seven of those eight total patients who achieved functional cure with the 60mg dose of imdusiran had HBsAg levels less than 1000 IU/mL at baseline.

According to the literature, patients with HBsAg levels <1000 IU/mL represent a significant portion of the cHBV population.

In addition to the patients who achieved functional cure, 40 more patients were able to remain off NA therapy for at least 48 weeks after discontinuing NA therapy following treatment with imdusiran.

In total, 46% (48/105) of all Phase 2a patients either achieved functional cure or remained off NA therapy after discontinuing NA therapy following treatment with imdusiran.

Of the 10 patients who were able to discontinue and remain off NA therapy for at least 48 weeks that are being followed in our rollover study, nine have continued to remain off NA therapy for periods ranging between 83 to 108 weeks.

All eight patients who achieved functional cure are participating in a rollover study and have maintained HBV DNA <LLOQ for between 58 to 109 weeks.

These results suggest that imdusiran has lasting durability in helping patients maintain viral suppression.

To date, six of those eight patients continue to sustain functional cure for periods ranging between 82 to 134 weeks, while two patients have seroreverted but remain virally suppressed and off NA therapy.

In addition to the patients who achieved functional cure during their Phase 2a clinical trials, 41 more patients were able to remain off NA therapy for at least 48 weeks during their clinical trials after discontinuing NA therapy following treatment with imdusiran.

In total, 47% (49/105) of all Phase 2a patients either achieved functional cure or remained off NA therapy after discontinuing NA therapy during their clinical trials following treatment with imdusiran.

Of the 10 patients who were able to discontinue and remain off NA therapy for at least 48 weeks who are currently being followed long-term in our rollover study, one patient achieved functional cure during the long-term follow-up period, and a total of eight patients have continued to remain off NA therapy for periods ranging between 96 to 131 weeks.

These results suggest that imdusiran has lasting durability in helping patients maintain viral suppression and may help patients achieve beneficial clinical outcomes years after completing finite imdusiran regimens.

Our imdusiran development program includes the following two Phase 2a clinical trials:

• Imdusiran in combination with IFN, a standard-of-care immunomodulator, and ongoing standard-of-care NA therapy in patients with cHBV infection (IM-PROVE I).

At the American Association for the Study of Liver Diseases (AASLD) – The Liver Meeting ® in November 2024, we presented new data from our IM-PROVE I Phase 2a clinical trial showing that six doses of imdusiran and 24 weeks of IFN added to ongoing NA therapy led to a functional cure rate of 50% (3/6) in hepatitis B e antigen (HBeAg) negative patients with baseline HBsAg levels less than 1000 IU/mL, and an overall functional cure rate of 25% (3/12).

• Imdusiran in combination with IFN, an approved immunomodulator, and ongoing standard-of-care NA therapy in patients with cHBV infection (IM-PROVE I).

At the American Association for the Study of Liver Diseases (AASLD) – The Liver Meeting ® in November 2024, we presented data from our IM-PROVE I Phase 2a clinical trial showing that six doses of imdusiran and 24 weeks of IFN added to ongoing NA therapy led to a functional cure rate of 50% (3/6) in hepatitis B e antigen (HBeAg) negative patients with baseline HBsAg levels less than 1000 IU/mL, and an overall functional cure rate of 25% (3/12).

Additionally, three cHBV patients from other cohorts in the IM-PROVE I clinical trial achieved functional cure.

Those patients who achieved a functional cure also seroconverted.

Those patients who achieved functional cure also seroconverted.

Furthermore, an additional 10 patients who did not achieve functional cure were able to remain off NA therapy for at least 48 weeks after discontinuing NA therapy following treatment with imdusiran.

At the AASLD – The Liver Meeting in November 2025, we presented new analysis from our IM-PROVE I Phase 2a clinical trial showing beneficial clinical outcomes were observed across all evaluated HBV genotypes (A to E).

These data from the IM-PROVE I trial suggest that the combination of imdusiran, 24 weeks of IFN and NA therapy was generally safe and well-tolerated with beneficial clinical outcomes.

These data from the IM-PROVE I trial suggest that the combination of imdusiran, 24 weeks of IFN and NA therapy was generally safe and well-tolerated with beneficial clinical outcomes, and that imdusiran may enhance responsiveness to IFN in HBV genotypes that are poor responders to IFN.

• Imdusiran in combination with VTP-300, Barinthus Biotherapeutics plc’s (Barinthus) HBV immunotherapeutic, and ongoing NA therapy in patients with cHBV infection, including a cohort with the addition of low dose nivolumab (Opdivo ® ) (IM-PROVE II).

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We continue to explore pipeline opportunities in the form of potential strategic alliances, in order to accelerate the development of these programs.

In April 2026, the FDA granted Fast Track designation for imdusiran for the treatment of cHBV.

The FDA’s Fast Track program is designed to facilitate the development and expedite the review of investigational therapies to treat serious conditions where the investigational therapy demonstrates the potential to address unmet medical need.

A drug granted Fast Track designation may be eligible for several benefits, including earlier and more frequent meetings and communications with the FDA and the potential for rolling review of its application.

If relevant criteria are met, investigational therapies that receive Fast Track designation may also qualify for Accelerated Approval or Priority Review of a Biologics License Application or New Drug Application.

RNAi therapeutic (imdusiran, AB-729)

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We are developing an RNAi therapeutic, imdusiran, that is designed to reduce HBV DNA, HBV RNA, HBsAg and other HBV antigen expression in people with cHBV infection.

Reducing HBsAg and HBV DNA are widely believed to be key prerequisites to enable a patient’s immune system to reawaken and respond against the virus.

Reducing HBsAg in addition to other viral proteins and HBV DNA are widely believed to be key prerequisites to potentiate an effective patient’s immune response against the virus.

Imdusiran has the following advantages over other RNAi therapeutics in development for cHBV infection:

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– Unique nucleotide sequence that is single trigger and targets all HBV transcripts including HBx from cccDNA and integrated HBV DNA.

– Specific chemical modifications and unique asymmetric RNA structure that reduces off-target effects while maintaining/enhancing potency and providing durable liver exposure and in vivo efficacy.

– Delivered at a lower dose and less frequently (4, 8 or 12 week intervals).

– Specific chemical modifications and unique asymmetric RNA structure that reduces off-target effects while maintaining/enhancing potency and providing durable liver exposure and in vivo therapeutic effect.

– Delivered at a low dose and infrequently (4, 8 or 12 week intervals).

– Immune activation properties with HBV-specific T-cell immune restoration and a decrease in exhausted T-cells in responder patients.

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We have completed IM-PROVE I, a randomized, open label, multicenter Phase 2a proof-of-concept clinical trial investigating the safety and antiviral activity of imdusiran in combination with a short course of IFN and ongoing NA therapy in 43 stably NA-suppressed, HBeAg negative, non-cirrhotic patients with cHBV infection.

Our primary intent for this trial was to initially lower HBsAg, HBV DNA and HBV RNA levels with imdusiran and then administer IFN as an immunomodulator to promote

anti-HBV immune reawakening.

Our belief in this trial was that if we can lower HBsAg and HBV DNA levels and promote immune reawakening, we may achieve sustained HBsAg seroclearance and HBV DNA <LLOQ, potentially leading to a functional cure.

Our primary intent for this trial was to initially lower HBsAg and other viral proteins, HBV DNA and HBV RNA levels with imdusiran and then administer IFN as an immunomodulator to promote anti-HBV immune responses.

Our belief in this trial was that if we can lower HBsAg, other viral proteins and HBV DNA levels and promote immune responses, we may achieve sustained HBsAg seroclearance and HBV DNA <LLOQ, potentially leading to a functional cure.

After patients received 24-weeks of dosing with imdusiran (60mg every 8 weeks, 4 doses) plus ongoing NA therapy, patients were randomized into one of four cohorts to receive a short course of IFN plus ongoing NA therapy for either 12 or 24 weeks, with or without up to two additional doses of imdusiran across an additional 16 week period.

After completion of the assigned IFN treatment period, all patients remained on NA therapy for the initial 24-week follow-up period, and then discontinued NA treatment, provided they met protocol-defined NA therapy discontinuation criteria.

After completion of the assigned IFN treatment period, all patients remained on NA therapy for a 24-week follow-up period, and then discontinued NA treatment, provided they met protocol-defined NA therapy discontinuation criteria.

Patients who discontinued NA therapy entered an intensive follow-up period for 48 weeks.

Select key data from 12 patients in Cohort A1 of this Phase 2a clinical trial who received 6 doses of imdusiran, 24 weeks of IFN and ongoing NA therapy, as presented at the AASLD – The Liver Meeting in November 2024, include:

• 50% (3/6) of patients with baseline HBsAg <1000 IU/mL achieved a functional cure.

• Overall, 25% (3/12) of patients achieved a functional cure.

• Those patients that achieved a functional cure also seroconverted with anti-HBs levels increasing as patients lost HBsAg.

• 50% (3/6) of patients with baseline HBsAg <1000 IU/mL achieved functional cure.

• Overall, 25% (3/12) of patients achieved functional cure.

• Those patients who achieved functional cure also seroconverted with anti-HBs levels increasing as patients lost HBsAg.

At the EASL Congress in May 2025, we presented a poster characterizing the demographics and virological markers of the six cHBV patients across dosing cohorts in the IM-PROVE I Phase 2a clinical trial who achieved functional cure.

The data showed that HBsAg at baseline was the only apparent marker in common associated with functional cure.

In a second poster, we reported that patients who achieved functional cure in the 24-week IFN treatment cohorts experienced HBsAg seroclearance that was associated with transient HBV RNA elevations that were preceded by or coincided with increases in immunological markers.

In a second poster, we reported that patients who achieved functional cure in the 24-week IFN treatment cohorts experienced HBsAg seroclearance associated with transient HBV RNA elevations that were preceded by or coincided with increases in immunological markers.

Additionally, a total of 10 patients in IM-PROVE I who did not achieve functional cure were still able to remain off NA therapy for at least 48 weeks after discontinuing NA therapy following treatment with imdusiran.

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IM-PROVE II Phase 2a proof-of-concept clinical trial evaluating imdusiran in combination with Barinthus’ VTP-300

Through a clinical collaboration agreement with Barinthus that we entered into in July 2021, we completed IM-PROVE II, a Phase 2a proof-of-concept clinical trial evaluating the safety, antiviral activity and immunogenicity of a combination treatment with Barinthus’ VTP-300, an HBV immunotherapy, administered after imdusiran in patients with cHBV infection.

Through a clinical collaboration agreement with Barinthus that we entered into in July 2021, we completed IM-PROVE II, a Phase 2a proof-of-concept clinical trial evaluating the safety, antiviral activity and immunogenicity of a combination treatment with Barinthus’ VTP-300, an HBV immunotherapeutic, administered after imdusiran in patients with cHBV infection.

The initial trial design enrolled 40 NA-suppressed, HBeAg negative or positive, non-cirrhotic cHBV infected patients.

Our primary intent for this trial was to initially lower HBsAg, HBV DNA and HBV RNA levels with imdusiran and then administer VTP-300 as an immunomodulator to promote anti-HBV immune reawakening.

Our primary intent for this trial was to initially lower HBsAg and other viral proteins, HBV DNA and HBV RNA levels with imdusiran and then administer VTP-300 as an immunomodulator to promote anti-HBV immune responses.

All patients received imdusiran (60mg every 8 weeks, 4 doses) plus NA therapy for 24 weeks.

After week 24, treatment with imdusiran was stopped.

Patients continued only on NA therapy and were randomized to receive VTP-300 or placebo at week 26 and week 30.

continued only on NA therapy and were randomized to receive VTP-300 or placebo at week 26 and week 30.

At week 48, all patients were evaluated for eligibility to discontinue NA therapy and were followed for an additional 24 to 48 weeks.

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At the AASLD – The Liver Meeting in November 2024, we presented data from this clinical trial showing that the addition of low dose nivolumab increased rates of HBsAg seroclearance in cHBV patients and that 23% (3/13) of patients who received the treatment regimen with low dose nivolumab achieved HBsAg seroclearance by week 48.

At the EASL Congress in May 2025,

we presented data showing that 25% (2/8) of patients with low dose nivolumab added to the treatment regimen and with baseline HBsAg<1000 IU/mL achieved functional cure.

At the EASL Congress in May 2025, we presented data showing that 25% (2/8) of patients with low dose nivolumab added to the treatment regimen and with baseline HBsAg<1000 IU/mL achieved functional cure.

Additionally, a total of 31 patients in IM-PROVE II who did not achieve functional cure were still able to remain off NA therapy for at least 48 weeks after discontinuing NA therapy following treatment with imdusiran at 60mg.

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Treatment with imdusiran, VTP-300, NA therapy and low dose nivolumab in this clinical trial was generally safe and well-tolerated.

There were no serious adverse events, Grade 3 or 4 adverse events, immune-related adverse events, or discontinuations due to adverse events.

There were no serious adverse events, immune-related adverse events, or discontinuations due to adverse events.

The IM-PROVE II clinical trial was managed by us, subject to oversight by a joint development committee comprised of representatives from both companies.

We and Barinthus retain full rights to our respective product candidates and split all costs associated with the clinical trial.

We and Barinthus retained full rights to our respective product candidates and split all costs associated with the clinical trial.

Pursuant to the agreement, the parties could have undertaken a larger Phase 2b clinical trial depending on the results of the initial Phase 2a clinical trial.

However, in January 2025, Barinthus announced a shift in its strategic business focus that included postponing further development of VTP-300 after its ongoing VTP-300 clinical trials have concluded.

However, in January 2025, Barinthus announced a shift in its strategic business focus that included postponing further development of VTP-300.

The parties do not intend to undertake a larger Phase 2b with this combination treatment regimen.

At the AASLD - The Liver Meeting in November 2025, we presented cumulative data across all of our imdusiran clinical trials demonstrating that imdusiran was safe and well-tolerated, and that beneficial clinical outcomes in our Phase 2a clinical studies were potentially linked to immune reawakening in patients.

At the AASLD - The Liver Meeting in November 2025, we presented cumulative data across all of our imdusiran clinical trials demonstrating that imdusiran was safe and well-tolerated at all tested repeat doses of 60mg or 90mg, and that beneficial clinical outcomes in our Phase 2a clinical trials were potentially linked to immune reawakening in patients.

Imdusiran Treatment Without Immunotherapeutic

In our single and multiple ascending dose Phase 1b clinical trial for imdusiran, we enrolled HBeAg negative and positive patients, as well as HBV DNA positive patients not on NA therapy.

Across all arms, 71% (44/62) of patients achieved HBsAg levels below 100 IU/mL, including 5% (3/62) of patients achieving HBsAg seroclearance.

Across all arms, which included doses up to 180mg, 71% (44/62) of patients achieved HBsAg levels below 100 IU/mL, including 5% (3/62) of patients who achieved HBsAg seroclearance.

Additionally, 56% (5/9) of patients who elected to discontinue NA therapy remained off NA therapy for at least three years after discontinuation.

Furthermore, all patients in all imdusiran clinical studies showed significant early decreases in HBsAg levels, often observed after the first or second dose of imdusiran.

Furthermore, all patients in all imdusiran clinical trials showed significant early decreases in HBsAg levels, often observed after the first or second dose of imdusiran.

In Group B of IM-PROVE II, after just 24 weeks of imdusiran dosing at just 60mg with only background NA therapy and no other combination agent, 37% (7/19) of patients were able to remain off NA therapy for at least 48 weeks after discontinuing NA therapy, including one patient who achieved HBsAg seroclearance.

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Oral PD-L1 Inhibitor (AB-101)

PD-L1 inhibitors complement our pipeline of agents and could potentially be an important part of a combination therapy for the treatment of HBV by reawakening the immune system.

PD-L1 inhibitors complement our pipeline of agents and could potentially be an important part of a combination therapy for the treatment of HBV by activating the immune system.

Highly functional HBV-specific T-cells within our immune system are believed to be required for long-term HBV viral resolution.

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AB-101 is our proprietary oral small-molecule PD-L1 inhibitor candidate that we believe will allow for controlled checkpoint blockade while minimizing the systemic safety issues often seen with checkpoint inhibitor antibody therapies.

AB-101 is differentiated from monoclonal antibody checkpoint inhibitors such as durvalumab (anti-PD-L1) and nivolumab (anti-PD-1) because it is liver centric, has a much shorter duration of effect in preclinical models (which may provide dosing and safety advantages), and has a novel mechanism of action as it binds to PD-L1 on the surface of cells causing dimerization, internalization and degradation of the PD-L1 protein.

AB-101 is differentiated from monoclonal antibody checkpoint inhibitors such as durvalumab (anti-PD-L1) and nivolumab (anti-PD-1)

because it is liver centric, has a much shorter duration of effect in preclinical models (which may provide dosing and safety advantages), and has a novel mechanism of action as it binds to PD-L1 on the surface of cells causing dimerization, internalization and degradation of the PD-L1 protein.

Phase 1a/1b clinical trial to evaluate safety, tolerability and PK/PD of AB-101 (AB-101-001)

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The data from Part 1 and Part 2 showed that AB-101 was well-tolerated with evidence of high receptor occupancy.

We have moved into Part 3 of this clinical trial which evaluates repeat doses of AB-101 for 28 days in patients with cHBV.

Part 3 of this clinical trial evaluated repeat doses of AB-101 for 28 days in patients with cHBV.

At the EASL Congress in May 2025, we presented data showing that a single dose of 10mg of AB-101 for 28 days in cHBV patients was well tolerated with PD-L1 receptor occupancy similar to that seen in healthy subjects at this dose.

At the AASLD - The Liver Meeting in November 2025, we presented a Poster of Distinction highlighting maximal PD-L1 receptor occupancy between 68-100% at the 30mg daily dose.

Treatment with AB-101 in Part 3 of this clinical trial has been generally safe and well-tolerated.

There have been no serious adverse events or early discontinuations due to AB-101 and no evidence of liver dysfunction to date.

Treatment with AB-101 in Part 3 of this clinical trial was generally safe and well-tolerated.

There were no serious adverse events related to AB-101 and no evidence of liver dysfunction.

Other Collaborations, Royalty Entitlements and Intellectual Property Litigation

Collaboration with Qilu Pharmaceutical Co., Ltd.

In December 2021, we entered into a technology transfer and license agreement (the Qilu License Agreement) with Qilu, pursuant to which we granted Qilu a sublicensable, royalty-bearing license, under certain intellectual property owned by us, which was non-exclusive as to development and manufacturing and exclusive with respect to commercialization of imdusiran, including pharmaceutical products that include imdusiran, for the treatment or prevention of hepatitis B in China, Hong Kong, Macau and Taiwan (Greater China and Taiwan).

In December 2021, we entered into a technology transfer and license agreement (the Qilu License Agreement) with Qilu, pursuant to which we granted Qilu a sublicensable, royalty-bearing license, under certain intellectual property owned by us, which was non-exclusive as to development and manufacturing and exclusive with respect to commercialization of imdusiran, including pharmaceutical products that include imdusiran, for the treatment or prevention of HBV in China, Hong Kong, Macau and Taiwan (Greater China and Taiwan).

In partial consideration for the rights granted by us, Qilu paid us a one-time upfront cash payment of $40 million on January 5, 2022 and agreed to pay us up to $245 million, net of withholding taxes, upon the achievement of certain technology transfer, development, regulatory and commercialization milestones.

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The royalties were to be payable on a product-by-product and region-by-region basis, subject to certain limitations.

Qilu was responsible for all costs related to developing, obtaining regulatory approval for, and commercializing imdusiran for the treatment or prevention of hepatitis B in Greater China and Taiwan.

Qilu was responsible for all costs related to developing, obtaining regulatory approval for, and commercializing imdusiran for the treatment or prevention of HBV in Greater China and Taiwan.

Qilu was required to use commercially reasonable efforts to develop, seek regulatory approval for, and commercialize at least one imdusiran product candidate in Greater China and Taiwan.

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Both parties also entered into a supply agreement and related quality agreement pursuant to which we would manufacture and supply Qilu with all quantities of imdusiran necessary for Qilu to develop and commercialize in Greater China and Taiwan until we had completed manufacturing technology transfer to Qilu and Qilu had received all approvals required for it or its designated contract manufacturing organization to manufacture imdusiran in Greater China and Taiwan.

Concurrent with the execution of the Qilu License Agreement, we entered into a Share Purchase Agreement (the Share Purchase Agreement) with Anchor Life Limited, a company established pursuant to the applicable laws and regulations of Hong Kong and an affiliate of Qilu (the Investor), pursuant to which the Investor purchased 3,579,952 of our common shares at a purchase price of USD $4.19 per share, which was a 15% premium on the thirty-day average closing price of our common shares as of the close of trading on December 10, 2021 (the Share Transaction).

shares as of the close of trading on December 10, 2021 (the Share Transaction).

We received $15.0 million of gross proceeds from the Share Transaction on January 6, 2022.

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(Alnylam) and Acuitas Therapeutics, Inc.

In 2012, we entered into a license agreement with Alnylam that entitles Alnylam to develop and commercialize products with our LNP technology in exchange for milestone and royalty payments.

We have two royalty entitlements to global net sales of ONPATTRO ® (Patisiran) (ONPATTRO), an RNA interference therapeutic currently being sold by Alnylam.

In 2012, we entered into a license agreement with Alnylam that entitles Alnylam to develop and commercialize products with our LNP technology.

In addition, we are entitled to receive payments upon the achievement of contractual milestones related to Alnylam’s use of our proprietary LNP technology in other products.

Alnylam’s ONPATTRO, which represents the first approved application of our LNP technology, was approved by the FDA and the European Medicines Agency (EMA) during the third quarter of 2018 and was launched by Alnylam immediately upon approval in the United States.

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If this royalty entitlement reverts to us, it has the potential to provide an active royalty stream or to be otherwise monetized again in full or in part.

From the inception of the royalty sale through September 30, 2025, an aggregate of $26.3 million of royalties have been earned by OMERS.

From the inception of the royalty sale through March 31, 2026, an aggregate of $26.7 million of royalties have been earned by OMERS.

We also are receiving a second royalty interest ranging from 0.75% to 1.125% on global net sales of ONPATTRO, with 0.75% applying to sales greater than $500 million, originating from a settlement agreement and subsequent license agreement with Acuitas.

This royalty entitlement from Acuitas has been retained by us and was not part of the royalty entitlement sale to OMERS.

In 2025, Alnylam began using our proprietary LNP technology in a product candidate to treat hepatocellular carcinoma (HCC), underscoring the important role our LNP technology plays in the delivery of nucleic acids to the body.

Genevant Sciences, Ltd.

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Additionally, if Genevant receives proceeds from an action for infringement by any third parties of our intellectual property licensed to Genevant, we would be entitled to receive, after deduction of litigation costs, 20% of the proceeds received by Genevant or, if less, tiered low single-digit royalties on net sales of the infringing product (inclusive of the proceeds from litigation or settlement, which would be treated as net sales).

Notwithstanding the preceding, in March 2025, we and Genevant agreed that we would be entitled to any award of damages in (or any proceeds of settlement of) certain pending patent litigation against Moderna and certain affiliates that is specifically allocated to Moderna’s vaccine for RSV known as mRESVIA ™ , and that, in the event there is no such specific allocation to mRESVIA in such award or settlement, the parties will discuss an appropriate allocation in good faith.

In July 2020, Roivant recapitalized Genevant through an equity investment and conversion of previously issued convertible debt securities held by Roivant.

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We have the right to have a non-voting observer attend meetings of Genevant’s Board of Directors.

As of September 30, 2025, we owned approximately 16% of the common equity of Genevant and the carrying value of our investment in Genevant was zero.

As of March 31, 2026, we owned approximately 16% of the outstanding common equity of Genevant and the carrying value of our investment in Genevant was zero.

Our entitlement to receive future royalties or sublicensing revenue from Genevant was not impacted by the recapitalization.

Patent Infringement Litigation vs.

United States:

On February 28, 2022, we and Genevant filed a lawsuit in the U.S.

District Court for the District of Delaware against Moderna, Inc.

and a Moderna affiliate (collectively, Moderna) seeking damages for infringement of U.S.

8,058,069, 8,492,359, 8,822,668, 9,364,435, 9,504,651, and 11,141,378 in the manufacture and sale of MRNA-1273, Moderna’s vaccine for COVID-19.

The patents relate to nucleic acid-lipid particles and lipid vesicles, as well as compositions and methods for their use.

In the lawsuit, we seek fair compensation for Moderna’s use of our patented technology that was developed with great effort and at great expense, without which Moderna’s COVID-19 vaccine would not have been successful.

In May 2022, Moderna filed a partial motion to dismiss the claims “relating to Moderna’s sale and provision of COVID-19 vaccine doses to the U.S.

Government” and argued that U.S.

taxpayers, not Moderna, are financially liable for any infringement by Moderna of our patents.

In November 2022, the court issued an Order denying Moderna’s motion.

In February 2023, the U.S.

Department of Justice filed a Statement of Interest in the action, and in March 2023, the court reaffirmed its denial of Moderna’s motion to dismiss.

The claim construction hearing was held in February 2024, and in April 2024, the court issued its claim construction order.

The court agreed with both of our positions regarding the Composition of Total Lipid (’069) Patent that:

(i) the claimed molar percentage (mol.

%) ranges can be met by any particle and is not limited to “finished” particles that are not subjected to further process steps;

and (ii) that the claimed mol.

% ranges include standard variation based on the number of significant figures recited in the claim.

The court also agreed with our position regarding the Cationic Lipid with Protonatable Tertiary Amine (’378) Patent that there is no limitation as to the mol.

% of the claimed cationic lipid.

Regarding the Encapsulation of mRNA (’651) Patent, the court held that “wherein at least 70% / at least 80% / about 90% of the mRNA in the formulation is fully encapsulated in the lipid vesicles” means “wherein at least 70% / at least 80% / about 90% of the mRNA is fully, as distinct from partially, contained inside the lipid vesicles”.

Fact discovery, expert discovery and summary judgment briefing have been completed, and a jury trial is scheduled for March 2026.

Additionally, in July 2025, the case was reassigned to a different judge in the same court.

International:

On March 3, 2025, we and Genevant filed five international lawsuits against Moderna seeking to enforce patents protecting our patented lipid nanoparticle technology.

These five lawsuits target alleged infringing activities by Moderna in 30 countries, including Austria, Belgium, Bulgaria, Canada, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Japan, Latvia, Lithuania, Luxembourg, Malta, Monaco, Netherlands, Norway, Poland, Portugal, Romania, Slovenia, Spain, Sweden, Switzerland/Liechtenstein, and Turkey.

We and Genevant are seeking monetary relief and injunctions against the continued manufacture and sale of Moderna’s COVID-19 vaccine and, in the Unified Patent Court, additional Moderna products which Moderna has represented use the same lipid nanoparticle technology as the COVID-19 vaccine, including its RSV vaccine.

The five international lawsuits are as follows:

Federal Court of Canada File No.

T-704-25, seeking a permanent injunction and damages or, if Genevant so elects, an accounting of Moderna’s profits, attributable to infringement of Canadian Patent No.

Tokyo District Court Case No.

2025 (Wa) 70079, seeking a permanent injunction and reasonable royalty for infringement of Japanese Patent No.

• Switzerland:

a case seeking a permanent injunction and monetary relief, which upon later choice of Genevant and Arbutus can include surrender of profits, damages or a reasonable royalty, for infringement of EP 2 279 254.

• Unified Patent Court:

Case 10280/2025, seeking permanent and provisional injunctions, as well as monetary damages, which can include recovery of Moderna’s unfair profits, from infringement of EP 2 279 254.

• Unified Patent Court:

Case 10280/2025, seeking permanent and provisional injunctions, as well as monetary damages, which can include recovery of Moderna’s unfair profits, from infringement of EP 4 241 767.

Where permitted to do so in the initial pleadings, we and Genevant submitted evidence from testing of commercial Moderna product samples sourced from the U.S.

and European Union indicating the samples contain lipid nanoparticles falling under the protective scope of the claims of our lipid composition patents.

In October 2025, where permitted to do so, we submitted additional testing evidence from the U.S.

case that indicates samples produced by Moderna in the U.S.

proceedings also contain lipid nanoparticles falling under the protective scope of the claims of our lipid composition patents.

Public oral hearings for the Unified Patent Court cases are scheduled for May 2026, and the trial in the Canadian case is set to begin in September 2027.

Under the terms of the Moderna Settlement Agreement, Moderna will make an aggregate $950.0 million Noncontingent Settlement Payment to us and Genevant on or before July 8, 2026.

In addition, Moderna is obligated to make an additional Contingent Settlement Payment of up to an aggregate $1.3 billion to us and Genevant upon the occurrence of certain events related to the Moderna §1498 Appeal, but which may be subject to repayment.

Under the Genevant License, we are entitled to receive, after deduction of litigation costs, 20% of the Noncontingent Settlement Payment, exclusive of our ownership of approximately 16% of the outstanding common equity of Genevant.

We currently expect to receive an estimated $178.7 million of the Noncontingent Settlement Payment, which includes reimbursement of our litigation costs.

Patent Infringement Litigation vs.

Pfizer and BioNTech

On April 4, 2023, we and Genevant filed a lawsuit in the U.S.

District Court for the District of New Jersey against Pfizer Inc.

(Pfizer) and BioNTech SE (BioNTech) seeking damages for infringement of U.S.

On April 4, 2023, we and Genevant filed a lawsuit in the United States District Court for the District of New Jersey against Pfizer/BioNTech seeking damages for infringement of United States Patent Nos.

and 11,318,098 in the manufacture and sale of any COVID-19 mRNA-LNP vaccines.

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The claim construction hearing occurred in December 2024, and in September 2025, the court issued a claim construction ruling, which construed the disputed claim terms in a manner we generally consider to be favorable.

The parties are awaiting further scheduling in the litigation.

Patent Infringement Litigation vs.

On February 28, 2022, we and Genevant filed a lawsuit in the United States District Court for the District of Delaware against Moderna seeking damages for infringement of United States Patent Nos.

8,058,069, 8,492,359, 8,822,668, 9,364,435, 9,504,651, and 11,141,378 in the manufacture and sale of MRNA-1273, Moderna’s vaccine for COVID-19.

On March 3, 2025, we and Genevant filed five international lawsuits against Moderna seeking to enforce patents protecting our patented LNP technology.

Together, these lawsuits comprise the Moderna LNP Litigation.

On March 3, 2026, we and Genevant entered into the Moderna Settlement Agreement with Moderna to resolve the Moderna LNP Litigation.

Pursuant to the Moderna Settlement Agreement, all parties filed stipulated judgments and stipulations of dismissal for the respective courts or tribunals to enter judgment, dismiss with prejudice or withdraw (as the case may be) all claims in the Moderna LNP Litigation, except that Moderna was allowed to file the Moderna §1498 Appeal.

The Moderna §1498 Appeal is an appeal of the consent judgment entered in the District Court solely with respect to whether §1498 bars our and Genevant’s claims for direct infringement and indirect infringement against Moderna for vaccine doses that were sold to the United States Government under a particular contract and characterized by the District Court as “vaccines that did not go directly to United States Government employees.”

Under the terms of the Moderna Settlement Agreement, Moderna will make an aggregate $950.0 million Noncontingent Settlement Payment to us and Genevant on or before July 8, 2026.

In addition, as described in more detail in, and subject to the terms of, the Moderna Settlement Agreement, Moderna will make an additional Contingent Settlement Payment of an aggregate $1.3 billion to us and Genevant (i) if the Court of Appeals for the Federal Circuit (whether by the initial panel, upon panel rehearing or en banc ) affirms, or if there is a final non-appealable judgment that affirms, the rejection of Moderna’s affirmative defense pursuant to §1498 by the District Court in its entirety or otherwise holds that §1498 does not bar our and Genevant’s claim against Moderna as to either or both of direct infringement and indirect infringement with respect to all of the doses subject to the Moderna §1498 Appeal, or (ii) upon a voluntary dismissal of the Moderna §1498 Appeal (any of the foregoing (clause (i) or (ii) above), an Arbutus/Genevant §1498 Victory).

If an appellate ruling were to hold that §1498 bars our and Genevant’s infringement claims as to some, but not all, of the doses subject to the Moderna §1498 Appeal, the Moderna Settlement Agreement provides that Moderna will pay us and Genevant a prorated amount of the Contingent Settlement Payment, calculated based on the number of doses for which §1498 bars our and Genevant’s infringement claims as clearly articulated by the Federal Circuit or, if not clearly articulated by the Federal Circuit, as mutually agreed by the parties or determined in an accelerated binding arbitration process.

Under certain circumstances, as described in more detail in, and subject to the terms of, the Moderna Settlement Agreement, if the Arbutus/Genevant §1498 Victory is subsequently overturned in Moderna’s favor in a final nonappealable decision, we and Genevant are required to return any Contingent Settlement Payment to Moderna, plus interest.

If, following an Arbutus/Genevant §1498 Victory, either (i) Moderna does not timely appeal such Arbutus/Genevant §1498 Victory or (ii) such Arbutus/Genevant §1498 Victory is subsequently affirmed in a final nonappealable decision, Moderna will have no further right to a potential repayment of the Contingent Settlement Payment.

The Moderna Settlement Agreement includes mutual financial covenants to protect the payment or repayment of the Contingent Settlement Payment, as described above.

The Moderna Settlement Agreement also contains customary mutual releases in favor of each of us/Genevant and Moderna in respect of the Moderna LNP Litigation.

In addition, the Moderna Settlement Agreement includes a fully paid-up, royalty free, irrevocable, non-exclusive, worldwide license and covenant not to sue granted to Moderna under any patents and patent applications owned or licensable by us or Genevant or our respective direct and indirect wholly owned subsidiaries that exist, or that claim priority to patents or patent applications that exist, as of the effective date of the Moderna Settlement Agreement, to make, sell and generally otherwise exploit Moderna’s SPIKEVAX™, mNEXSPIKE™ and mRESVIA™ vaccines and any other mRNA vaccines that include a lipid SM-102-based LNP formulation against an infectious disease and meet certain conditions, as well as a covenant not to sue with respect to certain other of our and Genevant’s patents and Moderna products.

On March 19, 2026, we and Genevant filed a complaint against the United States in the United States Court of Federal Claims, seeking to recover compensation for Moderna’s infringement for vaccine doses that were sold to the United States Government under a particular contract and were deemed by the District Court to be doses that were provided directly to United States Government employees.

The complaint also includes a protective request to recover compensation from the United States for any other vaccine doses where, as a result of the Moderna §1498 Appeal, §1498 is deemed to bar our and Genevant’s claims for direct infringement and indirect infringement against Moderna.

Moderna and Merck European Oppositions

On April 5, 2018, Moderna and Merck, Sharp & Dohme Corporation (Merck) filed Notices of Opposition to our European patent EP 2279254 (the ’254 Patent) with the European Patent Office (EPO), requesting that the ’254 Patent be revoked in its entirety for all contracting states.

We filed a response to Moderna and Merck’s oppositions in September 2018 and a hearing was conducted before the Opposition Division of the EPO in October 2019.

At the conclusion of the hearing, the EPO upheld an auxiliary request adopting the amendment, as put forth by us, of certain claims of the ’254 Patent.

In February 2020, Moderna and Merck filed Notices of Appeal challenging the EPO’s grant of the auxiliary request.

We filed our responses to the appeals in September 2020.

In March 2022, Moderna filed further written submissions to which we and Genevant responded in August 2022.

In April 2023, we and Genevant withdrew our auxiliary request, however, the original (main) request remains in the action.

We and Moderna informed the Board of Appeals that we would not object to a remittance of the matter without a hearing to the Opposition Division of the EPO.

The hearing in this matter before the Board of Appeals was subsequently cancelled and resubmitted to the Opposition Division (i.e., lower board) of the EPO.

In October 2023, the Opposition Division issued a summons for oral proceedings and provided its preliminary and non-binding opinion on the subject matter to be discussed at the hearing.

In November 2023, we responded to the summons and in January 2024, Moderna and Merck filed their reply to the written opinion of the Opposition Division, as well as to our written submission from November 2023.

We responded to Moderna and Merck’s reply in April 2024.

Oral proceedings were held in June 2024, and the Opposition Division upheld the ’254 Patent but declined our and Genevant’s request to broaden certain claims in the ’254 Patent.

Both parties appealed the Opposition Division’s decision and in March 2025, the Board of Appeals scheduled oral proceedings for January 2026.

On April 29, 2025, Moderna filed a revocation action on EPO patent EP 4 241 767 (the ’767 patent) with the EPO, requesting that the patent be revoked in its entirety for all contracting states.

On April 5, 2018, Moderna and Merck, Sharp & Dohme Corporation (together with its successors and affiliates, Merck) filed Notices of Opposition to our European patent EP 2279254 (the ’254 Patent) with the European Patent Office (EPO), requesting that the ’254 Patent be revoked in its entirety for all contracting states.

From 2018 until 2024, various hearings were held by different divisions of the EPO regarding requests submitted by all parties.

Oral proceedings were held in June 2024, and the Opposition Division of the EPO upheld the ’254 Patent but declined our and Genevant’s request to broaden certain claims in the ’254 Patent.

Both parties appealed the Opposition Division’s decision, and on January 15, 2026, in a verbal decision, the Board of Appeal of the EPO revoked the ’254 Patent.

We are awaiting a written decision from the Board of Appeal of the EPO regarding the revocation.

We disagree with the outcome, and upon receipt of the written decision, we plan to file a petition for review by the Enlarged Board of Appeal of the EPO.

The revocation was based on an EPO standard of “added matter” that does not apply in the United States.

In March 2026, pursuant to the Moderna Settlement Agreement, Moderna withdrew from this revocation proceeding.

In May 2026, we entered into an agreement with Merck (the Merck Agreement) where we, among other things, acknowledged that the Moderna Settlement Agreement covered a vaccine being jointly developed by Moderna and Merck and we agreed not to sue Merck regarding such vaccine, in exchange for Merck withdrawing from the revocation proceeding.

On May 6, 2026, Merck withdrew from this revocation proceeding.

We do not expect the EPO revocation decision to have an impact on the potential outcome, or timing, of our patent infringement litigation pending against Pfizer/BioNTech in the United States.

On April 29, 2025, Moderna filed a revocation action on our European patent EP 4241767 (the ’767 patent) with the EPO, requesting that the patent be revoked in its entirety for all contracting states.

In July 2025, Merck, Arrowhouse GmbH and Keltie LLP filed three additional revocation actions against the ’767 patent.

All opponents have submitted their opposition briefs and we are currently preparing our response.

Initial briefing has been completed and we are currently awaiting an initial hearing date.

In March 2026, pursuant to the Moderna Settlement Agreement, Moderna withdrew from this revocation proceeding.

On May 6, 2026, pursuant to the Merck Agreement, Merck withdrew from this revocation proceeding.

While we are the patent owner, the ’254 Patent, the ’767 Patent, and the other patents in our LNP portfolio have been licensed to Genevant under the Genevant License.

Potential Additional Payments Related to the Acquisition of Enantigen Therapeutics, Inc.

In October 2014, Arbutus Inc., our wholly-owned subsidiary, acquired all of the outstanding shares of Enantigen Therapeutics, Inc.

(Enantigen) pursuant to a stock purchase agreement.

The amount paid to Enantigen’s selling shareholders could be up to an additional $102.5 million in sales performance milestones in connection with the sale of the first commercialized product by us

for the treatment of HBV, regardless of whether such product is based upon assets acquired under this stock purchase agreement, and a low single-digit royalty on net sales of such first commercialized HBV product, up to a maximum royalty payment of $1.0 million that, if paid, would be offset against our performance milestone payment obligations.

CRITICAL ACCOUNTING POLICIES AND SIGNIFICANT JUDGMENTS AND ESTIMATES

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The following summarizes the results of our operations for the periods shown:

Three Months Ended September 30, Nine Months Ended September 30,

2025 2024 2025 2024

Three Months Ended March 31,

(in thousands)

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Operating expenses 10,218 27,463

Loss from operations (8,659) (21,440) (32,870) (62,386)

Income (loss) from operations 168,908 (25,699)

Other income 787 1,173

Net loss $ (7,742) $ (19,717) $ (29,745) $ (57,388)

Net income (loss) $ 169,695 $ (24,526)

Revenues are summarized in the following tables:

Three Months Ended September 30,

Three Months Ended March 31,

2026 % of Total 2025 % of Total

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Revenue from collaborations and licenses

Royalties from sales of ONPATTRO $ 280 53 % $ 644 48 %

Qilu Pharmaceutical Co., Ltd.

Acuitas Therapeutics, Inc.

$ 204 — % $ 504 29 %

Non-cash royalty revenue

Royalties from sales of ONPATTRO 249 47 % 572 43 %

Total revenue $ 529 100 % $ 1,339 100 %

Nine Months Ended September 30,

2025 % of Total 2024 % of Total

(in thousands, except percentages)

Revenue from collaborations and licenses

Royalties from sales of ONPATTRO $ 1,375 11 % $ 1,981 43 %

Qilu Pharmaceutical Co., Ltd.

— — % 812 46 %

License revenue from Genevant 178,741 100 % — — %

Non-cash royalty revenue

Royalties from sales of ONPATTRO 1,223 9 % 1,736 38 %

Alnylam Pharmaceuticals, Inc.

181 — % 448 25 %

Total revenue $ 179,126 100 % $ 1,764 100 %

Total revenue decreased $0.8 million for the three months ended September 30, 2025 compared to the same period in 2024, due primarily to a decrease in license royalty revenue from Alnylam and Acuitas due to lower sales of ONPATTRO in the 2025 period compared to the 2024 period.

Total revenue increased $8.4 million for the nine months ended September 30, 2025, compared to the same period in 2024, due primarily to recognizing the remaining $9.6 million of previously deferred revenue upon the conclusion of our strategic partnership with Qilu in June 2025, partially offset by a decrease in license royalty revenue from Alnylam and Acuitas due to lower sales of ONPATTRO in the 2025 period compared to the 2024 period.

Total revenue increased $177.4 million for the three months ended March 31, 2026 compared to the same period in 2025, due primarily to estimated license revenue from Genevant expected in 2026 related to our portion of the Noncontingent Settlement Payment.

Operating expenses

Operating expenses are summarized in the following tables:

Three Months Ended September 30,

2025 % of Total 2024 % of Total

(in thousands, except percentages)

Research and development $ 5,778 63 % $ 14,273 63 %

General and administrative 3,044 33 % 4,537 20 %

Change in fair value of contingent consideration 268 3 % 344 2 %

Restructuring costs 98 1 % 3,625 16 %

Total operating expenses $ 9,188 100 % $ 22,779 100 %

Nine Months Ended September 30,

Three Months Ended March 31,

2026 % of Total 2025 % of Total

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Research and development expenses consist primarily of personnel expenses, fees paid to clinical research organizations and contract manufacturers, consumables and materials, consulting, and other third-party expenses to support our clinical and preclinical activities, as well as a portion of stock-based compensation and general overhead costs.

Research and development expenses decreased $8.5 million and $25.0 million for the three and nine months ended September 30, 2025, respectively, compared to the same periods in 2024.

The decrease was due primarily to our decision in the third quarter of 2024 to cease all discovery efforts, halt preparations for a potential IM-PROVE III clinical trial and implement a 40% reduction in our workforce to streamline the organization to focus our efforts on advancing the clinical development of imdusiran and AB-101.

Research and development expenses decreased $4.8 million for the three months ended March 31, 2026, compared to the same period in 2025.

The decrease was due primarily to cost savings from our decisions to reduce our workforce and discontinue in-house scientific research, as well as lower clinical trial costs as studies neared completion.

A significant portion of our research and development expenses are not tracked by project as they benefit multiple projects or our technology platform and because our most-advanced programs are not yet in late-stage clinical development.

General and administrative

General and administrative expenses decreased $1.5 million and $5.2 million for the three and nine months ended September 30, 2025, respectively, as compared to the same periods in 2024, due primarily to a decrease in employee compensation-related expenses and a decrease in litigation-related legal fees.

General and administrative expenses increased $0.1 million for the three months ended March 31, 2026 as compared to the same period in 2025, due primarily to an increase in litigation-related legal fees driven by the settlement with Moderna, partially offset by cost-cutting efforts by the Company, which drove reductions in employee compensation-related expenses.

Change in fair value of contingent consideration

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In connection with these actions, we incurred a one-time restructuring charge in the first quarter of 2025 of $12.4 million, which includes approximately $6.0 million of cash severance and continued benefits paid, $2.4 million of non-cash expense related to the modification of equity awards, non-cash impairment charges for leasehold improvements and laboratory equipment of $1.9 million and $0.9 million, respectively, $0.9 million related to impairment of the right-of-use asset associated with the lease of our corporate headquarters and a $0.4 million accrual of lease-related operating expenses.

During the three months ended September 30, 2025, we recorded an additional $0.2 million of restructuring costs related to severance and benefits.

As of September 30, 2025, there was $0.5 million of accrued restructuring costs for severance payments and a $0.3 million accrual of lease-related operating expenses included in accounts payable and accrued liabilities.

As of March 31, 2026, there was less than $0.1 million of accrued restructuring costs for medical benefits and a $0.2 million accrual of lease-related operating expenses included in accounts payable and accrued liabilities.

Other income (loss)

The components of our other income (loss) are summarized in the following table:

Three Months Ended September 30, Nine Months Ended September 30,

2025 2024 2025 2024

Three Months Ended March 31,

(in thousands)

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Interest income

The decrease in interest income for the three and nine months ended September 30, 2025 compared to the same periods in 2024 was due primarily to less interest earned on our cash and investment balances due to a lower average balance and a general decrease in market interest rates.

The decrease in interest income for the three months ended March 31, 2026 compared to the same period in 2025 was due primarily to less interest earned on our cash and investment balances due to a lower average balance and a general decrease in market interest rates.

Interest expense

Interest expense for the three and nine months ended September 30, 2025 and 2024 consisted primarily of non-cash amortization of discount and issuance costs related to the sale of a portion of our ONPATTRO royalty interest to OMERS in July 2019.

Interest expense for the three months ended March 31, 2026 and 2025 consisted primarily of non-cash amortization of discount and issuance costs related to the sale of a portion of our ONPATTRO royalty interest to OMERS in July 2019.

The decrease is related to the declining balance of the unamortized discount and issuance costs.

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The following table summarizes our cash flow activities for the periods indicated:

Nine Months Ended September 30,

Three Months Ended March 31,

(in thousands)

Net loss $ (29,745) $ (57,388)

Net income (loss) $ 169,695 $ (24,526)

Non-cash items 1,061 5,866

Change in deferred license revenue (10,434) (880)

License receivable from Genevant (178,741) —

Net change in other operating items (125) 5,269

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Net cash provided by investing activities 2,199 11,349

Issuance of common shares pursuant to the Open Market Sale Agreement — 44,124

Cash provided by other financing activities 4,081 6,451

Net cash provided by financing activities 11,619 2,784

Effect of foreign exchange rate changes on cash and cash equivalents (10) 4

(Decrease) / Increase in cash and cash equivalents (13,922) 5,561

Increase in cash and cash equivalents 5,698 746

Cash and cash equivalents, beginning of period 18,008 36,330

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Since our incorporation, we have financed our operations through sales of equity, debt, revenues from research and development collaborations and licenses with corporate partners, royalty monetization, interest income on funds available for investment, and government contracts, grants and tax credits.

For the nine months ended September 30, 2025, $35.0 million of cash was used in operating activities compared to $54.5 million used in operating activities for the nine months ended September 30, 2024, a decrease of $19.6 million.

The decrease was due primarily to our decisions to cease all discovery efforts, halt preparations for a potential IM-PROVE III clinical trial, and decrease our workforce to further streamline the organization to focus our efforts on advancing the clinical development of imdusiran and AB-101.

For the nine months ended September 30, 2025, net cash provided by investing activities was $16.9 million, resulting primarily from maturities of investments in marketable securities of $131.4 million, partially offset by additional investments in marketable securities of $114.5 million.

For the nine months ended September 30, 2024, net cash provided by investing activities was $9.5 million, which resulted primarily from maturities of investments in marketable securities of $108.0 million, partially offset by additional investments in marketable securities of $98.3 million.

For the nine months ended September 30, 2025, net cash provided by financing activities was $4.1 million, which was primarily related to $3.9 million in proceeds from the issuance of common shares pursuant to the exercise of stock options.

For the nine months ended September 30, 2024, net cash provided by financing activities was $50.6 million, which included $44.1 million in proceeds from sales of common shares pursuant to the Sale Agreement (as defined below) and $6.1 million in proceeds from the issuance of common shares pursuant to the exercise of stock options.

For the three months ended March 31, 2026, $8.1 million of cash was used in operating activities compared to $13.4 million used in operating activities for the three months ended March 31, 2025, a decrease of $5.3 million.

The decrease was due primarily to our decisions to decrease our workforce and further streamline the organization to focus our efforts on advancing the clinical development of imdusiran and AB-101.

For the three months ended March 31, 2026, net cash provided by investing activities was $2.2 million, resulting primarily from maturities of investments in marketable securities of $16.0 million, partially offset by additional investments in marketable securities of $13.8 million.

For the three months ended March 31, 2025, net cash provided by investing activities was $11.3 million, which resulted primarily from maturities of investments in marketable securities of $46.1 million, partially offset by additional investments in marketable securities of $34.7 million.

For the three months ended March 31, 2026, net cash provided by financing activities was $11.6 million, which was primarily related to $11.5 million in proceeds from the issuance of common shares pursuant to the exercise of stock options.

For the three months ended March 31, 2025, net cash provided by financing activities was $2.8 million, which included $2.7 million in proceeds from the issuance of common shares pursuant to the exercise of stock options.

Sources of Liquidity

As of September 30, 2025, we had cash, cash equivalents and investments in marketable securities of $93.7 million.

We had no outstanding debt as of September 30, 2025.

Open Market Sale Agreement

Effective March 26, 2025, we terminated our Open Market Sale Agreement with Jefferies dated December 20, 2018, as amended (the Sale Agreement), under which we could offer and sell common shares, from time to time.

Prior to the termination of the Sale Agreement, we did not issue any common shares pursuant to the Sale Agreement during the nine months ended September 30, 2025.

For the nine months ended September 30, 2024, we issued 16,499,999 common shares pursuant to the Sale Agreement, resulting in net proceeds of approximately $44.1 million.

As of March 31, 2026, we had cash, cash equivalents and investments in marketable securities of $95.2 million.

We had no outstanding debt as of March 31, 2026.

Royalty Entitlements

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OMERS has assumed the risk of collecting up to $30 million of future royalty payments from Alnylam and we are not obligated to reimburse OMERS if it fails to collect any such future royalties.

From the inception of the royalty sale through September 30, 2025, we have recorded an aggregate of $26.3 million of non-cash royalty revenue for royalties earned by OMERS.

From the inception of the royalty sale through March 31, 2026, we have recorded an aggregate of $26.7 million of non-cash royalty revenue for royalties earned by OMERS.

If this royalty entitlement reverts to us, it has the potential to provide an active royalty stream or to be otherwise monetized again in full or in part.

In addition to the royalty from the Alnylam LNP license agreement, we are also receiving a second, lower royalty interest on global net sales of ONPATTRO originating from a settlement agreement and subsequent license agreement with Acuitas.

In addition to

the royalty from the Alnylam LNP license agreement, we are also receiving a second, lower royalty interest on global net sales of ONPATTRO originating from a settlement agreement and subsequent license agreement with Acuitas.

The royalty from Acuitas has been retained by us and was not part of the royalty sale to OMERS.

In addition, we are entitled to receive payments upon the achievement of contractual milestones related to Alnylam’s use of our proprietary LNP technology in other product candidates.

In December 2021, we entered into a technology transfer and exclusive license agreement with Qilu pursuant to which we granted Qilu an exclusive (with certain exceptions), sublicensable, royalty-bearing license, under certain intellectual property owned by us, to develop, manufacture and commercialize imdusiran for the treatment or prevention of cHBV infection in Greater China and Taiwan.

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Cash requirements

With the organizational changes announced during the first quarter of 2025, and our ongoing cost management efforts, we expect to significantly reduce our net cash burn in 2025 when compared to 2024.

With the organizational changes announced during the first quarter of 2025, and our ongoing cost management efforts, we expect to maintain our reduced net cash burn in 2026.

In the future, substantial additional funds would be required to continue with the active development of our pipeline products and technologies.

In particular, our funding needs may vary depending on a number of factors including:

• costs associated with prosecuting and enforcing our patent claims and other intellectual property rights, including our ongoing patent infringement matters against Moderna and Pfizer/BioNTech;

• costs associated with prosecuting and enforcing our patent claims and other intellectual property rights, including our ongoing patent infringement matter against Pfizer/BioNTech, the Moderna §1498 Appeal, and our lawsuit against the United States;

• a potential return of capital to our shareholders in connection with proceeds from the Moderna Settlement Agreement;

• revenue earned from our legacy collaborative partnerships and licensing agreements, including potential royalty payments from Alnylam’s ONPATTRO;

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• whether batches of product candidates that we manufacture fail to meet specifications resulting in clinical trial delays and investigational and remanufacturing costs;

• the decisions, and the timing of decisions, made by health regulatory agencies regarding our technology and product

• the decisions, and the timing of decisions, made by health regulatory agencies regarding our technology and product candidates;

• competing products, product candidates and technological and market developments.

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Compared sentence by sentence after normalising whitespace, quotation marks, case and digits, so re-formatting and restated figures do not read as changed language. Wording changes appear as one removal and one addition. The current filing and the prior one are authoritative.

What changed 10-Q

Item 2. Management’s Discussion and Analysis