Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

You should read the following discussion and analysis together with the consolidated financial statements and related notes included elsewhere herein.

This report includes forward-looking statements which, although based on assumptions that we consider reasonable, are subject to risks and uncertainties which could cause actual events or conditions to differ materially from those currently anticipated and expressed or implied by such forward-looking statements.

Discussions of 2023 items and year-to-year comparisons between 2024 and 2023 that are not included in this Form 10-K can be found within Management’s Discussion and Analysis of Financial Condition and Results of Operations in our Annual Report on Form 10-K for the year ended December 31, 2024.

Overview

We are a messenger RNA medicines company focused on the development of liver and respiratory rare disease therapeutics. We have ongoing Phase 2 clinical studies for our RNA therapeutic candidates to potentially treat ornithine transcarbamylase (OTC) deficiency and cystic fibrosis (CF).

We developed the world’s first approved self-amplifying messenger RNA (sa-mRNA) vaccine, KOSTAIVE® (“KOSTAIVE”), which we have partnered with Seqirus, Inc. (“CSL Seqirus”), a part of CSL Limited. KOSTAIVE has achieved approval in Japan, the European Union and the United Kingdom as a vaccine against COVID-19, and sales of KOSTAIVE began in Japan in October 2024.

We have several key platform technologies that we leverage to develop and advance a pipeline of mRNA-based therapeutics for rare genetic disorders with significant unmet medical needs and vaccines for infectious diseases. Current mRNA medicines have two critical components: the messenger RNA (“mRNA”) constructs and the lipid nanoparticles (“LNP”) which help deliver the mRNA to disease-relevant target tissues. We have extensive expertise in the design and optimization of mRNA constructs, including with respect to a type of mRNA technology known as self-amplifying mRNA (sa-mRNA). Our proprietary self-amplifying mRNA technology platform, or STARR® (“STARR”), has been demonstrated to induce a robust, longer-lasting and broader humoral immune response at lower dose levels than conventional mRNA-based vaccines. Our proprietary LNP delivery system, LUNAR® (“LUNAR”), is intended to address the major hurdle in RNA drug development, namely the effective and safe delivery of RNA to disease-relevant target tissues. LUNAR may enable multiple nucleic acid medicines. We also have significant expertise and valuable know-how in the development and scalability of complex and robust manufacturing processes required to deliver the next generation of nucleic acid medicines.

Our internal pipeline includes RNA therapeutic candidates to potentially treat ornithine transcarbamylase (OTC) deficiency and cystic fibrosis (CF), both rare diseases. In our vaccine program, we have partnered with CSL Seqirus, one of the world’s leading influenza vaccine providers, on the development and commercialization of mRNA vaccines for COVID-19, influenza and three other infectious diseases. In CSL Limited’s half-year results presented on February 11, 2026, CSL Limited reported an accounting write-down of approximately $430 million attributable to our collaboration agreement with CSL Seqirus, citing declining COVID-19 disease burden and more onerous U.S. regulatory requirements.

In our CF program, we enrolled and completed dosing in the three initially planned cohorts of our Phase 2 multiple ascending dose study of ARCT-032, confirming the safety and tolerability of ARCT-032 dosed daily for four weeks. This study was initiated in December 2024 and was designed to identify a safe and effective dose regimen in those with Class I (null) CFTR mutations and people with CF who do not benefit from CFTR modulators. In the study, six CF adults with Class I CFTR mutations inhaled 10 mg doses of ARCT-032 daily over 28 days. Interim results released in October 2025 demonstrated that the treatment was generally safe and well tolerated. Treatment-related adverse events (AEs) that were identified in the single-dose Phase 1 study were also observed in some participants for the first few doses but ceased with continued dosing. Bronchospasm has not been reported in this study thus far, neither with nor without albuterol pretreatment. One serious adverse event (SAE) occurred in a participant after the end of the dosing period. The safety review committee found no convincing evidence that the SAE is related to ARCT-032 and approved the study to proceed. We intend to initiate a 12-week safety and preliminary efficacy study in up to 20 CF participants in the first half of 2026, after the third cohort completes treatment. ARCT-032 has received Orphan Drug Designation by the U.S. Food and Drug Administration (the “FDA”) and Orphan Medicinal Product Designation by the European Medicines Agency (the “EMA”) for the treatment of CF, and Rare Pediatric Disease Designation from the FDA.

KOSTAIVE is the brand name approved in Japan and Europe for ARCT-154, which is the version of the sa-mRNA COVID vaccine encoding the ancestral strain of SARS-CoV-2, and also for updated variant-specific versions of this vaccine. We may use KOSTAIVE or the specific internally generated name, such as ARCT-154, ARCT-2301 and ARCT-2303, to identify a version of the vaccine.

In our OTC program, we have continued to conduct a Phase 2 double-blind multiple-dose study of ARCT-810. Five patients with OTC deficiency have now completed dosing, and a sixth patient has initiated dosing. A type C meeting with the FDA to discuss our plans for a proposed future pediatric study under the RDEP (Rare Disease Evidence Principles) is scheduled for the first half of 2026. ARCT-810 has received Orphan Drug Designation from the FDA and Orphan Medicinal Product Designation from the EMA for treatment of OTC deficiency, as well as Fast Track Designation and Rare Pediatric Disease Designation from the FDA.

Commercial sales of KOSTAIVE began in October 2024 in Japan by Meiji Seika Pharma, Ltd. (“Meiji”), CSL Seqirus’ exclusive partner in Japan, marking the first commercial sales of an Arcturus-developed product. In September 2025, Meiji launched a new presentation of KOSTAIVE in Japan. The product is a 2-dose vial lyophilized presentation incorporating the updated XEC variant strain. Approval for offshore manufacturing of the 2-dose vial lyophilized presentation was granted by Japan in August 2025, followed by approval for onshore manufacturing in January 2026. KOSTAIVE was approved by the European Commission (EC) in February 2025 and by the United Kingdom in January 2026, providing further validation of our platform by additional significant regulatory authorities.

In December 2024, we initiated dosing of an sa-mRNA vaccine candidate against pandemic avian influenza (bird flu) in a Phase 1 trial funded by the Biomedical Advanced Research and Development Authority (“BARDA”). The study results were received in the second half of 2025, indicating a favorable tolerability and safety profile and the ability to induce a robust and durable humoral immune response in young and older adults.

We also improved our platform technologies and advanced our early-stage research activities and manufacturing process development and operations. We conducted exploratory platform development activities, including the evaluation of genome editing, and new targeting approaches, where our LUNAR and STARR platforms could be useful for identification and development of additional products for our portfolio.

Our activities since inception have consisted principally of performing research and development activities, clinical research activities, general and administrative activities and raising capital to fund those efforts. Our activities are subject to significant risks and uncertainties, including failing to secure additional funding before we achieve sustainable revenues and profit from operations. As of December 31, 2025, we had an accumulated deficit of $514.6 million.

Liquidity and Capital Resources

From the Company’s inception through the year ended December 31, 2025, the Company has funded its operations principally with the proceeds from revenues earned through collaboration agreements and government contracts, the sale of capital stock and long-term debt. During fiscal year 2025, we received milestone payments totaling $39.1 million from CSL Seqirus. At December 31, 2025, the Company’s balance of cash and cash equivalents, including restricted cash, was $232.8 million.

CSL Seqirus, Inc. Collaboration and License Agreement

In November 2022, we entered into the CSL Collaboration Agreement with CSL Seqirus for the global exclusive rights to research, develop, manufacture and commercialize self-amplifying mRNA vaccines. The CSL Collaboration Agreement became effective on December 8, 2022, following clearance under the Hart-Scott-Rodino Antitrust Improvements Act.

Under the CSL Collaboration Agreement, CSL Seqirus receives global exclusive rights to our technology for vaccines against SARS-CoV-2 (COVID-19), influenza and three other infectious diseases. Specifically, the collaboration agreement grants CSL Seqirus a license to our STARR mRNA technology and LUNAR lipid-mediated delivery, as well as mRNA drug substance and drug product manufacturing expertise. CSL has also been granted global non-exclusive rights in the field of pandemic preparedness (i.e., pathogens identified as priority diseases by the WHO), with the right to convert to an exclusive license.

The CSL Collaboration Agreement sets forth how the parties will collaborate to research and develop vaccine candidates. In the COVID-19 field, we undertake activities for certain regulatory filings for our leading

self-amplifying mRNA vaccine candidate in COVID-19, ARCT-154, in the United States and Europe and for research and development activities of a next-generation COVID vaccine candidate. CSL Seqirus leads and is responsible for all other research and development in COVID-19, influenza and the other fields.

We received an up-front payment of $200.0 million, with the potential to receive development milestones totaling more than $1.3 billion if all products are registered in the licensed fields. We also are entitled to potentially receive up to $3.0 billion in commercial milestones based on “net sales” of vaccines in the various fields. In addition, we are entitled to receive a 40% share of net profits from COVID-19 vaccine sales and up to low double-digit royalties of annual net sales for vaccines against influenza, pandemic preparedness and three additional infectious diseases. Entitlement to all such payments is subject to the strict conditions, requirements, royalty reduction provisions and other limitations set forth in the CSL Collaboration Agreement.

Either party may terminate the CSL Collaboration Agreement on a field-by-field basis for material breach by the other party, following notice and opportunity to cure. CSL Seqirus may also terminate the collaboration agreement in its entirety or on a field-by-field basis for any reason or no reason whatsoever, with certain limitations. The CSL Collaboration Agreement may also be terminated by CSL Seqirus for safety reasons, clinical data nonviability, commercial nonviability and other specified reasons.

In March 2024, we entered into Amendment Number Two to the CSL Collaboration Agreement to reflect updates to the development program and other adjustments consistent with our prior disclosures regarding the Collaboration and License Agreement (“Amendment Number Two”). Amendment Number Two, among other things, adjusts (i) the development plans for certain product candidates, (ii) various development milestones related to such product candidates, (iii) provisions of the CSL Collaboration Agreement related to specific royalty payments, (iii) provisions of the CSL Collaboration Agreement related to distributors, and (iv) proprietary payment calculations related to the foregoing.

On May 30, 2025, we initiated an arbitration against CSL Seqirus before the International Chamber of Commerce, seeking payment of a milestone under the CSL Collaboration Agreement based on the European Commission’s grant of marketing authorization for a presentation of KOSTAIVE®in the European Union.

In CSL Limited’s half-year results presented on February 11, 2026, CSL Limited reported an accounting write-down of approximately $430 million attributable to our collaboration agreement with CSL Seqirus, citing declining COVID-19 disease burden and more onerous U.S. regulatory requirements.

Wells Fargo Credit Agreement

On April 21, 2023, the Company’s wholly-owned subsidiary, Arcturus Therapeutics, Inc. entered into a credit agreement with Wells Fargo Bank, National Association (“Wells Fargo”) whereby Wells Fargo agreed to make a $50.0 million revolving credit line available to the Company (as amended, the “Wells Fargo Loan”) with each Wells Fargo Loan evidenced by a revolving line of credit note (each, a “Note”). On June 26, 2024, the parties entered into Amendment No. 1 to the Wells Fargo Loan, whereby the term was extended by one year to April 2026.

Borrowings under the agreement bore interest at a rate of 1.00% above either the Daily Simple SOFR or Term SOFR (as such terms are defined in the Wells Fargo Loan), with “SOFR” being the rate per annum equal to the secured overnight financing rate as administered by the Federal Reserve Bank of New York. If an Event of Default (as defined in the credit agreement) had occurred, then all Wells Fargo Loans would bear interest at a rate equal to 2.00% above the interest rate applicable immediately prior to the occurrence of the Event of Default.

The original term of the agreement was two years, with an option for one-year renewals subject to Wells Fargo approval and the Company furnishing to Wells Fargo a non-refundable commitment fee equal to 0.25% of the Wells Fargo Loan amount for each such renewal. There was no penalty for terminating the agreement and no penalty for terminating the facility prior to the maturity date of the Wells Fargo Loan. As collateral, the Company had agreed to pledge $55.0 million in cash to be held at the Company’s securities accounts with Wells Fargo Securities, LLC, an affiliate of Wells Fargo, pursuant to a security agreement.

In December 2025, the Company terminated the credit agreement and related security agreement, and the $55.0 million of cash previously pledged as collateral was released and is no longer classified as restricted cash.

Grant from the Biomedical Advanced Research and Development Authority

On August 31, 2022, we entered into a cost reimbursement contract (the “BARDA Contract”) with the Biomedical Advanced Research and Development Authority (“BARDA”), a division of the Office of the Assistant Secretary for Preparedness and Response (“ASPR”) within the U.S. Department of Health and Human Services (“HHS”) to support the development of a low-dose pandemic influenza candidate based on our proprietary self-amplifying messenger RNA-based vaccine platform. The BARDA Contract is to support our non-clinical and pre-clinical development, early-stage clinical development through Phase 1, and associated drug product manufacturing, regulatory and quality-assurance activities over a period of three years. It provides for reimbursement by BARDA of our permitted costs up to $63.2 million. As of December 31, 2025, the remaining available funding net of revenue earned was $26.7 million.

General Financial Resources

A portion of our current cash balance is expected to be utilized during fiscal year 2026 to fund (i) advances to our LUNAR-CF program in clinical trials, (ii) the continued Phase 2 trial of ARCT-810, our LUNAR-OTC candidate, (iii) expenses incurred prior to customer payments under the CSL Collaboration Agreement and BARDA agreement and (iv) continued exploratory activities related to our platform and other general administrative activities.

Our future capital requirements are difficult to forecast and will depend on many factors that are out of our control. If we are unable to maintain sufficient financial resources, our business, financial condition and results of operations will be materially and adversely affected. There can be no assurance that we will be able to obtain additional needed financing on acceptable terms or at all. Additionally, equity or debt financings may have a dilutive effect on the holdings of our existing shareholders.

We expect to continue to incur additional losses in the long term, and we will need to raise additional debt or equity financing or enter into additional partnerships to fund development. Our ability to transition to profitability is dependent on regulatory approvals and subsequent sales of KOSTAIVE, and identifying and developing other successful mRNA drug and vaccine candidates. If we are not able to achieve planned milestones or incur costs in excess of our forecasts, we will need to reduce discretionary spending, discontinue the development of some or all of our programs, which will delay part of our development programs, all of which will have a material adverse effect on our ability to achieve our intended business objectives.

Funding Requirements

We anticipate that we will continue to generate losses for the foreseeable future, and we expect the losses to increase as we continue the development of, and seek regulatory approvals for, our product candidates, and begin commercialization of our products. As a result, we will require additional capital to fund our operations in order to support our long-term plans. We believe that our current cash position will be sufficient to meet our anticipated cash requirements through at least the next twelve months, assuming, among other things, no significant unforeseen expenses and continued funding from partners at anticipated levels. We intend to seek additional capital through equity and/or debt financings, collaborative or other funding arrangements with partners or through other sources of financing when and as needed. Should we seek additional financing from outside sources, we may not be able to raise such financing on terms acceptable to us or at all. If we are unable to raise additional capital when required or on acceptable terms, we may be required to scale back or discontinue the advancement of product candidates, reduce headcount, liquidate our assets, file for bankruptcy, reorganize, merge with another entity, or cease operations.

Our future funding requirements are difficult to forecast and will depend on many factors, including but not limited to the following:

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the development of our cystic fibrosis and OTC deficiency therapeutic candidates;

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the achievement of milestones under our strategic alliance agreements;

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maintaining and/or expanding our manufacturing network and capabilities;

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the terms and timing of any other strategic alliance, licensing and other arrangements that we may establish, including those with CSL Seqirus and CSL Seqirus’ arrangement with Meiji, and any related payments thereunder;

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the initiation, progress, timing and completion of preclinical studies and clinical trials for our product candidates;

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the number and characteristics of product candidates that we pursue;

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the outcome, timing and cost of regulatory approvals;

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delays that may be caused by changing regulatory requirements;

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the cost and timing of hiring new employees to support our continued growth;

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the costs involved in filing and prosecuting patent applications and enforcing and defending patent claims;

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the costs and timing of procuring clinical and commercial supplies of our product candidates;

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the costs and timing of establishing sales, marketing and distribution capabilities;

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the costs associated with legal proceedings;

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the costs associated with potential litigation related to collaboration agreements; and

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the extent to which we acquire or invest in businesses, products or technologies.

The following table shows a summary of our cash flows for the years ended December 31, 2025 and 2024:

Year Ended December 31,

Cash provided by (used in):

Investing activities (230 ) (648 )

Net decrease in cash and restricted cash $ (61,119 ) $ (54,977 )

Operating Activities

Net cash used in operating activities was $74.3 million for the year ended December 31, 2025, compared to $59.7 million for the year ended December 31, 2024. The $14.5 million increase was primarily due to a $29.7 million increase in accounts receivable and a $21.2 million decrease in accrued liabilities, reflecting the timing of billings, collections, and payments, as well as a $12.6 million decrease in share-based compensation due to reduced headcount and a lower stock price. These changes were partially offset by a $31.3 million smaller decrease in deferred revenue compared to the prior year, a $15.2 million reduction in net loss, a $7.5 million increase in cash provided by prepaid expenses and other assets, and the net impact of other working capital and non-cash items, which together reduced the overall increase in cash used in operating activities.

Investing Activities

Net cash used in investing activities of $0.2 million in 2025 and $0.6 million in 2024 reflected the acquisition of property and equipment.

Financing Activities

Net cash provided by financing activities was $13.4 million for the year ended December 31, 2025, compared to $5.4 million in 2024. The primary driver of the increase was an $11.7 million increase in proceeds from the issuance of common stock under our Sales Agreement for at‐the‐market equity offerings, partially offset by a $3.6 million decrease in proceeds from the exercise of stock options.

Results of Operations

The following discussion and analysis of our financial condition and results of operations should be read in conjunction with the consolidated financial statements included in this Annual Report. Our historical results of operations and the year-to-year comparisons of our results of operations that follow are not necessarily indicative of future results.

Revenues

We enter into arrangements with pharmaceutical and biotechnology partners and government agencies that may contain upfront payments, license fees for research and development arrangements, research and development funding, milestone payments, option exercise and exclusivity fees and royalties on future sales. The following table summarizes our total revenues for the periods indicated:

Revenue decreased by $70.3 million during the year ended December 31, 2025 as compared to the year ended December 31, 2024. The decrease during 2025 primarily relates to a $72.2 million decrease in revenue related to the CSL collaboration agreement, primarily due to a $33.1 million decrease in milestone achievements during 2025 as compared to 2024, and a $15.8 million decrease in revenue related to CSL commercial supply agreements, along with decreased revenue recognition from amortization during 2025 as a result of reduced development activities. The decrease was partially offset by an increase in grant revenue of $0.9 million related to the reimbursable research and development expenses for the agreements with BARDA and the Gates Foundation.

Operating Expenses

Our operating expenses consist of research and development and general and administrative expenses.

Operating expenses:

The following table presents our total research and development expenses by category:

Research and Development Expenses, net

Our research and development expenses consist primarily of external manufacturing costs, in-vivo research studies and clinical trials performed by contract research organizations, clinical and regulatory consultants, personnel related expenses, facility related expenses and laboratory supplies related to conducting research and development activities.

Research and development expenses were $112.2 million for the year ended December 31, 2025, compared with $195.2 million for the year ended December 31, 2024. The decrease was primarily driven by lower manufacturing and clinical costs related to the LUNAR‐COVID program, reflecting the program’s transition from a development program to the commercial phase. Additional decreases were attributable to lower manufacturing costs for the LUNAR‐CF and LUNAR‐FLU programs, as well as lower clinical costs associated with the LUNAR‐OTC

program. These reductions were partially offset by higher clinical costs for Phase 2 of the LUNAR‐CF program. Payroll and benefits expenses also decreased, primarily due to lower stock‐based compensation expense and a reduction in headcount.

Early-stage programs represent programs that are in the pre-clinical or Phase 1 clinical stage and may be partnered or unpartnered, and primarily includes the LUNAR-FLU program which is partnered with CSL Seqirus. Discovery technologies represent our efforts to expand our product pipeline and are primarily related to pre-partnered studies and new capabilities assessment. A few of our programs are part of our collaborative relationships. The related expenses may be partially offset with funds that have been reimbursed or awarded to the Company and consist of external manufacturing costs, lab supplies, equipment, and consulting and professional fees. Expenses for both early-stage programs and discovery technologies are expected to decrease as we shift our focus to later-stage programs.

Payroll and benefits primarily consists of employee salaries and benefits, share-based compensation and consultant costs. We expect that payroll and benefits costs will not increase over the next twelve months

Facilities and equipment expenses include rent, common area maintenance (“CAM”) costs, depreciation, shipping costs and various other costs related to the operation of our two office and laboratory locations. These costs increased primarily due to a lease‐related impairment recognized in the fourth quarter after the Company vacated an office location with no further operational use.

General and Administrative Expenses

General and administrative expenses consist primarily of salaries and related benefits for our executive, administrative and accounting functions and professional service fees for legal and accounting services as well as other general and administrative expenses.

General and administrative expenses were $46.1 million and $52.8 million for the years ended December 31, 2025 and 2024, respectively. The decrease was primarily due to reduced share-based compensation expense as well as reduced payroll and benefits associated with reductions in headcount.

Finance income (expense), net

Interest expense (9 ) — (9 ) 100 %

Interest income is generated on cash and cash equivalents. The decrease in interest income from 2024 to 2025 was the result of lower interest rates during the year ended 2025 and a decrease in cash and cash equivalents.

Critical Accounting Policies and Estimates

Our significant accounting policies are summarized in “Note 2 Summary of Significant Accounting Policies,” included in our consolidated financial statements included elsewhere in this annual report on Form 10-K.

The preparation of our consolidated financial statements in conformity with “GAAP” requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the consolidated financial statements, and the reported amounts of expenses during the reporting period. Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, assumptions related to revenue recognition, accrual of research and development expenses, determination of incremental borrowing rates, and the valuations of stock options. We based our estimates on historical experience, known trends and other market-specific or other relevant factors that we believe to be reasonable under the circumstances. On an ongoing basis, management evaluates these estimates when there are changes in circumstances, facts and experience. Changes in estimates are recorded in the period in which they become known. Actual results could differ from those estimates.

Revenue Recognition

We recognize revenue when control of the products and services is transferred to our customers in an amount that reflects the consideration we expect to receive from our customers in exchange for those products and services. This process involves identifying the contract with a customer, determining the performance obligations in the contract, determining the contract price, allocating the contract price to the distinct performance obligations in the contract, and recognizing revenue when the performance obligations have been satisfied.

Our collaboration agreements typically contain promised goods and services, including technology licenses or options to obtain technology licenses, research and development and regulatory services. Upon entering into a collaboration agreement, we are required to make the following judgments:

Identifying the performance obligations and measuring progress

Our assessment of what constitutes a separate performance obligation requires us to apply judgment. Specifically, we are required to identify which goods and services we are required to provide under the contract are distinct, if any. For performance obligations that are satisfied over time, we typically use the percentage-of-completion method which requires us to estimate the total forecasted costs required to complete the performance obligation. Adjustments to these estimates could materially impact the timing and amount of recognized revenue. If actual costs exceed initial estimates, revenue recognized to date may need to be adjusted downward, negatively impacting current period results. Conversely, favorable cost variances could accelerate revenue recognition.

Determining the transaction price, including any variable consideration

To determine the transaction price, we review the amount of consideration we are eligible to earn under the agreement. We apply a constraint to any payments we may receive in the future to avoid significant reversals since the payments are typically not probable because they are contingent upon certain future events.

We are required to reassess the total transaction price at each reporting period to determine if we should include additional payments that have become probable in the transaction price.

Allocating the transaction price to each of our performance obligations

When we allocate the transaction price to more than one performance obligation, we make estimates of the relative stand-alone selling price of each performance obligation because we do not typically sell our goods or services on a stand-alone basis. The estimate of the relative stand-alone selling price requires us in some cases to make significant judgments. In cases where we deliver a license at the start of an agreement, we use valuation methodologies, such as costs to recreate plus margin, to value the license. Additionally, when we estimate the selling price for research and development and regulatory services, we make estimates, including: the number of internal hours we will spend on the services, the cost of work we and third parties will perform and the cost of clinical trial material we will use.

The revenue we recognize each period is comprised of several types of revenue, including license fees, amortization from upfront payments, milestone payments, research and development and other services. Each of these types of revenue require us to make various judgments and estimates.

Amortization from Upfront Payments

For certain agreements, we recognize revenue from the amortization of upfront payments as we perform research and development, technology transfer and consulting services. We use an input method to estimate the amount of revenue to recognize each period. This method requires us to make estimates of the total costs we expect to incur in order to complete our promised research and development services or the total length of time it will take us to complete our promised research and development services. If we change our estimates, we may have to adjust our revenue.

Milestone Payments

When recognizing revenue related to milestone payments, we typically judge and estimate whether the milestone payment is probable (discussed in detail above under “Determining the transaction price, including any variable consideration”).

License Fees

In some cases, we deliver a license upon execution of an agreement. If we determine that our partner has full use of the license and we do not have any additional material performance obligations related to the license after delivery, then we consider the license to be a separate performance obligation. We generally recognize as license revenue the total amount of the transaction price we determine to be allocated to the performance obligation based upon the relative stand-alone selling price of a license when we deliver the license to our partner. We discuss the estimates we make related to the relative stand-alone selling price of a license in detail above under “Allocating the transaction price to our performance obligations.”

Research and Development Expenses, Including Clinical Trial Accruals/Expenses

Research and development costs consist of salaries and benefits, including share-based compensation, laboratory supplies and facility costs, as well as fees paid to other entities that conduct certain research and development activities on our behalf, such as clinical research organizations, or CROs, and contract manufacturing organizations, or CMOs. Research and development costs are expensed as incurred.

Clinical trial expenses are a significant component of research and development expenses, and we outsource a significant portion of these clinical trial activities to third parties. Third-party clinical trial expenses include investigator fees, site and patient costs, CRO costs, and costs for central laboratory testing and data management. The accrual for site and patient costs includes inputs such as estimates of patient enrollment, patient cycles incurred, clinical site activations, and other pass-through costs. These inputs are required to be estimated due to a lag in receiving the actual clinical information from third parties. Payments for these activities are based on the terms of the individual arrangements, which may differ from the pattern of costs incurred, and are reflected on the balance sheets as prepaid assets or accrued expenses. These third-party agreements are generally cancelable, and related costs are recorded as research and development expenses as incurred. Non-refundable advance clinical payments for goods or services that will be used or rendered for future research and development activities are recorded as a prepaid asset and recognized as expense as the related goods are delivered or the related services are performed. When evaluating the adequacy of the accrued expenses, we analyze progress of the studies, including the phase or completion of events, invoices received and contracted costs. We make estimates of our accrued balances as of each balance sheet date based on facts and circumstances known to our internal personnel at that time. We periodically confirm the accuracy of our estimates with the service providers and make adjustments if necessary. Judgments and estimates may be made in determining the accrued balances at the end of any reporting period. Actual results could differ from the estimates made. Our historical clinical trial accrual estimates have not been materially different from our actual costs.

Leases

We cannot readily determine the interest rate implicit in the lease, therefore, we use our incremental borrowing rate to measure lease liabilities. The incremental borrowing rate is the rate of interest that we would have to pay to borrow over a similar term, and with a similar security, the funds necessary to obtain an asset of a similar value to the right-of-use, or ROU, asset in a similar economic environment. The incremental borrowing rate therefore reflects what we ‘would have to pay’, which requires estimation when no observable rates are available or when they need to be adjusted to reflect the terms and conditions of the lease. We estimate the incremental borrowing rate using observable inputs (such as market interest rates) when available and are required to make certain entity and asset-specific estimates. The incremental borrowing rate used in the calculation of the present

value of lease payments in calculating lease liabilities and the corresponding ROU requires the use of significant judgment by management.

Share-Based Compensation

We recognize compensation expense related to stock options granted to employees and nonemployees based on the estimated grant date fair value and recognize forfeitures as they occur. We estimate the grant date fair value, and the resulting share-based compensation expense, using the Black-Scholes option-pricing model for service-based and performance-based awards. The grant date fair value of the share-based awards is recognized on a straight-line basis over the requisite service period, which is typically the vesting period of the respective awards. The Black-Scholes option-pricing model requires the use of highly subjective assumptions to determine the fair value of share-based awards. Such assumptions involve inherent uncertainties and the application of significant judgment. As a result, if factors or expected outcomes change and we use significantly different assumptions or estimates, our share-based compensation could be materially different.

Item 7A. Quantitative and Qualitative Disclosures About Market Risk

Our primary exposure to market risk is interest income and expense sensitivity, which is affected by changes in the general level of United States interest rates. Due to the nature of our investments, we believe that we are not subject to any material market risk exposure. We do not hold a material balance in foreign currencies or engage in derivative financial instruments that could materially impact our financial position.

Item 8. Financial Statements and Supplementary Data

The consolidated financial statements and related financial statement schedules required to be filed are listed in the Index to Consolidated Financial Statements and are incorporated herein and in Item 15 of Part IV of this Annual Report on Form 10-K.

Item 9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosure

None.

Item 9A. Controls and Procedures

Evaluation of Disclosure Controls and Procedures

Our disclosure controls and procedures (as defined in Rules 13a-15(e) or 15d-15(e)) under the Securities Exchange Act of 1934, as amended (the “Exchange Act”) are designed to ensure that information required to be disclosed in the reports that we file or submit under the Exchange Act is recorded, processed, summarized, and reported within the time periods specified in the SEC’s rules and forms and to ensure that information required to be disclosed is accumulated and communicated to management, including our principal executive and financial officers, to allow timely decisions regarding disclosure. Our Chief Executive Officer and Principal Financial Officer, with assistance from other members of management, have reviewed the effectiveness of our disclosure controls and procedures, and, based on their evaluation, have concluded that the disclosure controls and procedures were effective as of December 31, 2025.

Management’s Report on Internal Control Over Financial Reporting

Our management is responsible for establishing and maintaining an adequate system of internal control over financial reporting and for the assessment of the effectiveness of internal control over financial reporting as defined in Rule 13a-15(f) under the Exchange Act. Our internal control over financial reporting is designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with “U.S. GAAP” and includes those policies and procedures that: (1) pertain to the maintenance of records that accurately and fairly reflect our transactions and the dispositions of our assets; (2) provide reasonable assurance that our transactions are recorded as necessary to permit preparation of financial statements in accordance with “GAAP” and that our receipts and expenditures are being made only in accordance with appropriate authorizations; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use or disposition of our assets that could have a material effect on our financial statements.

Management assessed our internal control over financial reporting as of December 31, 2025 based on the criteria established in Internal Control-Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission. Management's assessment included evaluation of such elements as the

design and operating effectiveness of key financial reporting controls, process documentation, accounting policies, and our overall control environment. This assessment is supported by testing and monitoring performed both by our Internal Audit function and our Finance function.

Based on our assessment, management concluded that our internal control over financial reporting was effective as of December 31, 2025.

Management reviewed the results of its assessment with our Audit Committee. The effectiveness of our internal control over financial reporting as of December 31, 2025 has been audited by Deloitte & Touche LLP, an independent registered public accounting firm, and their opinion is stated in their report, which is included in Part II, Item 8 of the Annual Report on Form 10-K.

Remediation of Previously Reported Material Weakness

As previously reported in Part II, Item 9A. “Controls and Procedures” of our Annual Reports on Form 10-K for the fiscal year ended December 31, 2024, we identified a material weakness related to information technology general controls (“ITGCs”) that support the financial reporting process. Specifically, the remediated material weakness related to ineffective controls over (i) user access to ensure appropriate segregation of duties and adequate restriction of user and privileged access to financial applications, programs and data, to the appropriate personnel; (ii) program change management for financial applications to ensure that information technology (“IT”) program and data changes affecting financial IT applications and underlying accounting records are identified, tested, authorized and implemented appropriately; and (iii) IT operations controls to ensure that critical interface jobs are monitored.

We have completed execution of our remediation plan for this material weakness and, as of December 31, 2025, successfully remediated this material weakness by implementing the following measures:

•

updated and enhanced the IT policies and relevant internal controls to consider and address ITGCs including access security and change management;

•

limited elevated access profiles in financially relevant IT systems and software to appropriate personnel;

•

developed and enhanced access administration controls over provisioning, deprovisioning, and authentication;

•

developed and enhanced user access reviews for financially relevant IT systems;

•

designed and refined controls over change management and IT operations controls to monitor critical interface jobs;

•

hired an internal audit manager with an appropriate level of knowledge and experience;

•

engaged an accounting advisory firm to assist with the documentation, evaluation, remediation, and testing of our internal control over financial reporting; and

•

provided training to control owners and relevant personnel to improve documentation that supports effective control activities, including evidence over the completeness and accuracy of information used in controls.

Changes in Internal Control over Financing Reporting

Other than the remediation efforts completed and described above, there were no changes in our internal control over financial reporting during the fiscal quarter ended December 31, 2025 that materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

Inherent Limitations on Effectiveness of Disclosure Controls and Procedures, and Internal Controls Over Financial Reporting

Our management, including our principal executive officer and principal financial officer, does not expect that our disclosure controls and procedures or our internal control over financial reporting will prevent all errors and all fraud. A control system, no matter how well designed and operated, can provide only reasonable, not absolute, assurance that the objectives of the control system are met. Further, the design of a control system must reflect the fact that there are resource constraints, and the benefits of controls must be considered relative to their costs.

Because of the inherent limitations in all control systems, no evaluation of controls can provide absolute assurance that all control issues and instances of fraud, if any, have been detected. These inherent limitations include the realities that judgments in decision-making can be faulty, and that breakdowns can occur because of a simple error or mistake. Additionally, controls can be circumvented by the individual acts of some persons, by collusion of two or more people or by management override of the controls. The design of any system of controls is also based in part upon certain assumptions about the likelihood of future events, and there can be no assurance that any design will succeed in achieving its stated goals under all potential future conditions; over time, controls may become inadequate because of changes in conditions, or the degree of compliance with policies or procedures may deteriorate. Due to inherent limitations in a cost-effective control system, misstatements due to error or fraud may occur and not be detected.

Report of Independent Registered Public Accounting Firm

To the Stockholders and the Board of Directors of Arcturus Therapeutics Holdings Inc.

Opinion on Internal Control Over Financial Reporting

We have audited the internal control over financial reporting of Arcturus Therapeutics Holdings, Inc. and subsidiaries (the “Company”) as of December 31, 2025, based on criteria established in Internal Control — Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO). In our opinion, the Company maintained, in all material respects, effective internal control over financial reporting as of December 31, 2025, based on criteria established in Internal Control — Integrated Framework (2013) issued by COSO.

We have also audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the consolidated financial statements as of and for the year ended December 31, 2025, of the Company and our report dated March 3, 2026, expressed an unqualified opinion on those financial statements.

Basis for Opinion

The Company’s management is responsible for maintaining effective internal control over financial reporting and for its assessment of the effectiveness of internal control over financial reporting, included in the accompanying Management's Report on Internal Control over Financial Reporting. Our responsibility is to express an opinion on the Company’s internal control over financial reporting based on our audit. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audit in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether effective internal control over financial reporting was maintained in all material respects. Our audit included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, testing and evaluating the design and operating effectiveness of internal control based on the assessed risk, and performing such other procedures as we considered necessary in the circumstances. We believe that our audit provides a reasonable basis for our opinion.

Definition and Limitations of Internal Control Over Financial Reporting

A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (2) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become

inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

/s/ Deloitte & Touche LLP

San Diego, California

March 3, 2026

Item 9B. Other Information

Rule 10b5-1 Trading Plans

For the three months ended December 31, 2025, none of our directors or officers adopted or terminated a "Rule 10b5-1 trading arrangement" (as defined in Item 408 of Regulation S-K of the Exchange Act) intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) under the Exchange Act.

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections

Not Applicable.

PART III

Item 10. Directors, Executive Officers and Corporate Governance

Information required by this item will be contained in our Definitive Proxy Statement for our 2026 Annual Meeting of Stockholders, to be filed pursuant to Regulation 14A with the Securities and Exchange Commission within 120 days of December 31, 2025. Such information is incorporated herein by reference.

Item 11. Executive Compensation

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

Item 13. Certain Relationships and Related Transactions, and Director Independence

Item 14. Principal Accounting Fees and Services

PART IV

Item 15. Exhibits, Financial Statement Schedules

(a)

(1) The information required by this item is included in Item 8 of Part II of this Annual Report.;

(2) Financial statement schedules not listed above have been omitted because information required to be set forth therein is not applicable, not required, or the information required by such schedules is shown in the consolidated financial statements or the notes thereto.

(3) See the exhibit index preceding the signature pages to this Annual Report, which is incorporated by reference herein.

(b) See the exhibit index preceding the signature pages to this Annual Report, which is incorporated by reference herein.

Item 16. Form 10-K Summary

None.

Exhibit Index

ExhibitNumber Description

4.1* Description of Registrant’s Securities.

ExhibitNumber Description

19.1* Arcturus Therapeutics Holdings, Inc. Insider Trading Policy

21.1* List of subsidiaries of Arcturus Therapeutics Holdings, Inc.

23.1* Consent of Independent Registered Public Accounting Firm

23.2* Consent of Independent Registered Public Accounting Firm

24.1* Power of Attorney (included on the signature page of this Annual Report).

97.1* Arcturus Therapeutics Holdings, Inc. Clawback Policy

101.SCH Inline XBRL Taxonomy Extension Schema

104 Cover Page Interactive Data File (embedded within the Inline XBRL document)

* Filed herewith.

† Management compensatory plan, contract or arrangement.

SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this Report to be signed on its behalf by the undersigned, thereunto duly authorized.

ARCTURUS THERAPEUTICS HOLDINGS INC.

Date: March 3, 2026 By: /s/ Joseph E. Payne

Name: Joseph E. Payne

Title: President, Chief Executive Officer and Director

The undersigned officers and directors of Arcturus Therapeutics Holdings Inc., hereby severally constitute and appoint Joseph E. Payne and Dr. Padmanabh Chivukula, and each of them individually, with full power of substitution and resubstitution, as their true and lawful attorneys and agents, to do any and all acts and things in their name and behalf in their capacities as directors and officers and to execute any and all instruments for them and in their names in the capacities indicated below, which said attorneys and agents, may deem necessary or advisable to enable said corporation to comply with the Securities Exchange Act of 1934, as amended, and any rules, regulations and requirements of the Securities and Exchange Commission, in connection with this Annual Report on Form 10-K, including specifically but without limitation, power and authority to sign for them or any of them in their names in the capacities indicated below, any and all amendments hereto, and they do hereby ratify and confirm all that said attorneys and agents, or either of them, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, this Annual Report has been signed below by the following persons on behalf of the Registrant and in the capacities and on the dates indicated.

Name Title Date

Joseph E. Payne (principal executive officer)

/s/ Dr. Moncef Slaoui Chairman of the Board March 3, 2026

Dr. Moncef Slaoui

/s/ Joseph Roberts Corporate Controller March 3, 2026

Joseph Roberts (principal financial and accounting officer)

/s/ Dr. Magda Marquet Director March 3, 2026

Dr. Magda Marquet

/s/ James Barlow Director March 3, 2026

James Barlow

/s/ Edward Holmes Director March 3, 2026

Edward Holmes

/s/ Dr. Peter Farrell Director March 3, 2026

Dr. Peter Farrell

/s/ Dr. John Markels Director March 3, 2026

Dr. John Markels

/s/ Jing Marantz Director March 3, 2026

Jing Marantz

INDEX TO CONSOLIDATED FINANCIAL STATEMENTS

Report of Independent Registered Public Accounting Firm (PCAOB ID: 34) F-2

Report of Independent Registered Public Accounting Firm (PCAOB ID: 42) F-4

Consolidated Balance Sheets as of December 31, 2025 and 2024 F-5

Notes to Consolidated Financial Statements F-9

F-1

Report of Independent Registered Public Accounting Firm

To the shareholders and the Board of Directors of Arcturus Therapeutics Holdings, Inc.

Opinion on the Financial Statements

We have audited the accompanying consolidated balance sheets of Arcturus Therapeutics Holdings, Inc. and subsidiaries (the “Company”) as of December 31, 2025, and 2024, the related consolidated statements of operations, comprehensive loss, stockholder’s equity, and cash flows, for each of the two years in the period ended December 31, 2025 and the related notes (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2025 and 2024, and the results of its operations and its cash flows for each of the two years in the period ended December 31, 2025, in conformity with accounting principles generally accepted in the United States of America.

We have also audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Company’s internal control over financial reporting as of December 31, 2025, based on criteria established in Internal Control — Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission and our report dated March 3, 2026, expressed an unqualified opinion on the Company’s internal control over financial reporting.

Basis for Opinion

These financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on the Company’s financial statements based on our audits. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

Critical Audit Matter

The critical audit matter communicated below is a matter arising from the current-period audit of the financial statements that was communicated or required to be communicated to the audit committee and that (1) relates to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective, or complex judgments. The communication of critical audit matters does not alter in any way our opinion on the financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the accounts or disclosures to which it relates.

CollaborationRevenue — Refer to Note 2 and Note 3 to the financial statements

Critical Audit Matter Description

The Company has entered into a license and collaborative research and development arrangement with Seqirus, Inc. There are five distinct performance obligations under this arrangement. The Company recognizes revenue over time for all performance obligations except for the vaccine license. The vaccine license is recognized at the point in time it is transferred. The accounting for revenue recognized over time measures the progress using an input method which is based on costs incurred toward the satisfaction of the performance obligation. As of December 31, 2025, Collaboration revenue was $67.2 million, of which $66 million relates to the agreement with Seqirus, Inc.

Given the judgments necessary to estimate total costs to be incurred to satisfy the performance obligations, as well as the high volume of expense data used in the revenue calculation, auditing such estimates required extensive audit effort and a high degree of auditor judgment when performing audit procedures and evaluating the results of those procedures.

F-2

How the Critical Audit Matter Was Addressed in the Audit

Our audit procedures related to the recognition of revenue for the Seqirus, Inc. arrangement included the following, among others:

•

We tested the operating effectiveness of controls over collaboration revenue, including those related to the determination of the timing and amount of revenue recognized.

•

We evaluated the total costs incurred related to each performance obligation by inspecting, on a sample basis, underlying source documents to determine costs were recorded to the correct performance obligation.

•

We evaluated the assumptions used in the estimates of total costs and the estimated measure of progress for recognizing revenue by:

Analyzing period-over-period changes in the total cost assumption, identifying any significant fluctuations.

Inspecting third-party evidence of the agreed-upon total costs to be incurred and comparing that to the total cost to be incurred used by the Company in the calculation.

/s/ Deloitte & Touche LLP

San Diego, California

March 3, 2026

We have served as the Company’s auditor since 2024.

F-3

Report of Independent Registered Public Accounting Firm

To the Stockholders and the Board of Directors of Arcturus Therapeutics Holdings Inc.

Opinion on the Financial Statements

We have audited the accompanying consolidated statements of operations and comprehensive loss, changes in stockholders’ equity and cash flows of Arcturus Therapeutics Holdings Inc. and its subsidiaries (the Company) for the year ended December 31, 2023, and the related notes (collectively referred to as the “consolidated financial statements”). In our opinion, the consolidated financial statements present fairly, in all material respects, the results of the Company’s operations and its cash flows for the year ended December 31, 2023, in conformity with U.S. generally accepted accounting principles.

Basis for Opinion

These financial statements are the responsibility of the Company's management. Our responsibility is to express an opinion on the Company’s financial statements based on our audit. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audit in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. Our audit included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audit also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audit provides a reasonable basis for our opinion.

/s/ Ernst & Young LLP

We served as the Company's auditor from 2018 to 2024.

San Diego, California

March 14, 2024

except for Note 12, as to which the date is

March 6, 2025

F-4

ARCTURUS THERAPEUTICS HOLDINGS INC. AND ITS SUBSIDIARIES

CONSOLIDATED BALANCE SHEETS

As of December 31,

(in thousands, except per share data) 2025 2024

Assets

Current assets:

Prepaid expenses and other current assets 4,973 9,977

Liabilities and Stockholders’ Equity

Current liabilities:

Deferred revenue, net of current portion — 12,604

Operating lease liability, net of current portion 20,784 24,998

Stockholders’ equity:

Total liabilities and stockholders’ equity $ 271,148 $ 344,069

The accompanying notes are an integral part of these consolidated financial statements.

F-5

ARCTURUS THERAPEUTICS HOLDINGS INC. AND ITS SUBSIDIARIES

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS

Year Ended December 31,

Revenue:

Operating expenses:

Gain (loss) from foreign currency 382 (471 ) (229 )

Gain on debt extinguishment — — 33,953

(Benefit) provision for income taxes — (4 ) 1,835

Net loss per share, basic and diluted $ (2.40 ) $ (3.00 ) $ (1.12 )

F-6

ARCTURUS THERAPEUTICS HOLDINGS INC. AND ITS SUBSIDIARIES

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS’ EQUITY

Additional Total

Common Stock Paid-In Accumulated Stockholders’

(in thousands) Shares Amount Capital Deficit Equity

Issuance of common stock upon exercise of stock options 238 — 2,668 — 2,668

Issuance of common stock under equity plans 35 — 609 — 609

Issuance of common stock upon exercise of stock options 228 — 4,736 — 4,736

Issuance of common stock under equity plans 40 — 682 — 682

Issuance of common stock upon exercise of stock options 104 — 1,109 — 1,109

Issuance of common stock under equity plans 35 — 585 — 585

The accompanying notes are an integral part of these consolidated financial statements.

F-7

ARCTURUS THERAPEUTICS HOLDINGS INC. AND ITS SUBSIDIARIES

CONSOLIDATED STATEMENTS OF CASH FLOWS

Year Ended December 31,

Operating activities

Adjustments to reconcile net loss to net cash used in operating activities:

Gain on debt extinguishment — — (33,953 )

Foreign currency transaction loss 382 471 90

Other non-cash expenses — — 502

Impairment of right‐of‐use assets 1,897 — —

Changes in assets and liabilities:

Prepaid expenses and other current assets 5,004 (2,456 ) 1,165

Investing activities

Acquisition of property and equipment (230 ) (648 ) (2,901 )

Net cash used in investing activities (230 ) (648 ) (2,901 )

Financing activities

Proceeds from issuance of common stock under equity plans 585 682 609

Proceeds from issuance of common stock, net of issuance costs 11,688 — —

Net cash provided by (used in) financing activities 13,382 5,418 (24,087 )

Year Ended December 31,

Supplemental disclosure of cash flow information

Cash paid for interest $ — $ — $ 2,127

Cash paid for income taxes $ — $ 1,407 $ —

Non-cash investing activities

Right-of-use assets acquired through operating leases $ — $ 2,736 $ —

Non-cash asset disposal $ 2,345 $ 473 $ —

The accompanying notes are an integral part of these consolidated financial statements.

F-8

ARCTURUS THERAPEUTICS HOLDINGS INC. AND ITS SUBSIDIARIES

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

Note 1. Organization

Description of Business

Arcturus Therapeutics Holdings Inc. (the “Company” or "Arcturus") is a messenger RNA medicines company focused on the development of liver and respiratory rare disease therapeutics. Arcturus became a clinical stage company in 2020 when it announced that its Investigational New Drug (“IND”) application for ornithine transcarbamylase (“OTC”) deficiency and its Clinical Trial Application (“CTA”) for candidate LUNAR-COV19 were approved by applicable health authorities. In 2023, our COVID-19 vaccine, ARCT-154 (also referred to as KOSTAIVE®), received marketing authorization approval in Japan for adults 18 years and older, and in September 2024 KOSTAIVE became the world’s first approved and commercially available self-amplifying RNA (sa-mRNA) vaccine.

Note 2. Summary of Significant Accounting Policies

Basis of Presentation and Principles of Consolidation

The accompanying consolidated financial statements include the accounts of Arcturus Therapeutics Holdings Inc. and its subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. These consolidated financial statements are prepared in conformity with accounting principles generally accepted in the United States (“U.S. GAAP”), which requires management to make estimates and assumptions regarding the valuation of certain debt and equity instruments, the equity method investment, share-based compensation, accruals for liabilities, income taxes, revenue and deferred revenue, leases, expense accruals, and other matters that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Although these estimates are based on management’s knowledge of current events and actions the Company may undertake in the future, actual results could materially differ from those estimates.

Segment Information

Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision-maker in making decisions regarding resource allocation and assessing performance. The Company and its chief operating decision-maker view the Company’s operations and manage its business in one operating segment, which includes all activities related to the discovery, development and commercialization of messenger RNA medicines.

Cash and Cash Equivalents

Cash equivalents are short-term highly liquid investments that are readily convertible to cash with original maturities of three months or less at the date of purchase.

Restricted cash

Restricted cash includes cash required to be set aside as security for lease payments and to maintain a letter of credit for the benefit of the landlord for the Company’s offices.At December 31, 2025 and 2024, the Company had restricted cash of $1.9 million in conjunction with property leases in San Diego, California, and such restriction is expected to be removed at the end of the lease term.

Arcturus Therapeutics Holdings Inc. and its Subsidiaries

Notes to Consolidated Financial Statements — Continued

Fair Value Measurements

Fair value is defined as the exit price, or the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants as of the measurement date. A hierarchy has been established for inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that the most observable inputs be used when available.

Observable inputs are inputs that market participants would use in valuing the asset or liability developed based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company’s assumptions about the factors market participants would use in valuing the asset or liability developed based upon the best information available under the circumstances. The hierarchy consists of three levels. Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities. Level 2 inputs include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, and inputs (other than quoted prices) that are observable for the asset or liability, either directly or indirectly. Level 3 inputs are unobservable inputs for the asset or liability. Categorization within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement.

Accounts Receivable

Accounts receivable are recorded at the net invoice value and are non-interest bearing. The Company considers receivables past due based on the contractual payment terms. The Company reserves for specific receivables if collectability is no longer reasonably assured. Estimates for allowances for doubtful accounts are determined based on existing contractual obligations, historical payment patterns, and individual customer circumstances. The Company reevaluates such reserves on a regular basis and adjusts its reserves as needed. Once a receivable is deemed to be uncollectible, such balance is charged against the reserve. No reserves have been recorded as of December 31, 2025 or 2024.

Concentration of Credit Risk and Significant Customers

The Company is exposed to concentrations of credit risk primarily related to cash, cash equivalents, and accounts receivable.

Cash and Cash Equivalents

The Company mitigates credit risk exposure by maintaining cash and cash equivalents only with high-credit-quality financial institutions and investing in instruments with short maturities. The Company continuously monitors counterparty risk to minimize potential financial exposure.

Accounts Receivable Concentration

As of December 31, 2025 and 2024, the Company had significant concentrations of credit risk related to accounts receivable from a limited number of customers. The following customers accounted for 10% or more of total accounts receivable in each respective period:

As of December 31, 2025:

•

BARDA – 64% of total accounts receivable

•

CSL – 19% of total accounts receivable

As of December 31, 2024:

•

BARDA – 60% of total accounts receivable

•

CSL – 20% of total accounts receivable

The Company monitors its credit exposure through regular assessments of counterparty risk and maintains ongoing collection efforts to mitigate potential credit losses.

Revenue Concentration

The Company generates a substantial portion of its revenue from a limited number of key customers. The following customers accounted for 10% or more of total revenue for each period:

F-10

Arcturus Therapeutics Holdings Inc. and its Subsidiaries

Notes to Consolidated Financial Statements — Continued

For the year ended December 31, 2025:

•

CSL – 80% of total revenue

•

BARDA – 16% of total revenue

For the year ended December 31, 2024:

•

CSL – 91% of total revenue

For the year ended December 31, 2023:

•

CSL – 92% of total revenue

Given this concentration, the Company’s financial performance and cash flows may be materially impacted if there are changes in demand, contract renewals, or the financial condition of these key customers. The Company continues to evaluate opportunities to expand its customer base and mitigate concentration risk over time.

Joint Ventures, Equity Method Investments and Variable Interest Entities

Investments for which the Company exercises significant influence, but does not have control are accounted for under the equity method. Equity method investment activity is related to the Company's joint venture in ARCALIS, Inc. with Axcelead, Inc. The Company’s share of the investees’ results is presented as either income or loss from equity method investees in the accompanying consolidated statements of operations and comprehensive loss. As of December 31, 2025, the carrying value of the equity-method investment in ARCALIS remained at zero.

Property and Equipment, net

Property and equipment are stated at cost, net of accumulated depreciation and amortization. The cost of property and equipment is depreciated or amortized using the straight-line method over the respective useful lives of the assets, ranging from three to five years. Leasehold improvements are amortized using the straight-line method over the shorter of the estimated useful life of the asset or the lease term. Long-lived assets, including property and equipment are reviewed for impairment whenever events or circumstances indicate that the carrying amount of these assets may not be recoverable. The determinants used for this evaluation include management’s estimate of an asset’s ability to generate positive income from operations and positive cash flow in future periods, as well as the strategic significance of the assets to the Company’s business objectives. The Company did not recognize any impairment losses for the years ended December 31, 2025, 2024 or 2023.

Comprehensive Loss

Comprehensive loss is defined as the change in stockholders’ equity during a period from transactions and other events and circumstances from non-owner sources. There was no other comprehensive loss or income tax effect related to unrealized losses in the years ended December 31, 2025, 2024 or 2023.

Revenue Recognition

At contract inception, the Company analyzes its collaboration arrangements to assess whether such arrangements involve joint operating activities performed by parties that are both active participants in the activities and exposed to significant risks and rewards dependent on the commercial success of such activities and therefore within the scope of ASC Topic 808, Collaborative Arrangements (ASC 808). For collaboration arrangements within the scope of ASC 808 that contain multiple elements, the Company first determines which elements of the collaboration reflect a vendor-customer relationship and are therefore within the scope of ASC 606.

The Company determines revenue recognition for arrangements within the scope of Topic 606 by performing the following five steps: (i) identify the contract; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when, or as, the company satisfies a performance obligation.

F-11

Arcturus Therapeutics Holdings Inc. and its Subsidiaries

Notes to Consolidated Financial Statements — Continued

The terms of the Company’s revenue agreements include license fees, upfront payments, milestone payments, reimbursement for research and development activities, option exercise fees, consulting and related technology transfer fees and royalties on sales of commercialized products. The event-based milestone payments represent variable consideration, and the Company uses the most likely amount method to estimate this variable consideration because the Company will either receive the milestone payment or will not, which makes the potential milestone payment a binary event. The most likely amount method requires the Company to determine the likelihood of earning the milestone payment. Given the high degree of uncertainty around achievement of these milestones, the Company determines the milestone amounts to be fully constrained and does not recognize revenue until the uncertainty associated with these payments is resolved. The Company will recognize revenue from sales-based royalty payments when or as the sales occur. The Company will re-evaluate the transaction price in each reporting period as uncertain events are resolved and other changes in circumstances occur.

A performance obligation is a promise in a contract to transfer a distinct good or service to the collaborative partner and is the unit of account in Topic 606. A contract’s transaction price is allocated to each distinct performance obligation based on relative standalone selling price and recognized as revenue when, or as, the performance obligation is satisfied.

For performance obligations that are recognized over time, the Company measures the progress using an input method. The input methods used are based on the effort expended or costs incurred toward the satisfaction of the performance obligation. The Company estimates the amount of effort expended, including the time estimated it will take to complete the activities, or costs incurred in a given period, relative to the estimated total effort or costs to satisfy the performance obligation. This approach requires the Company to make numerous estimates and use significant judgment. If estimates or judgments change over the course of the collaboration, a cumulative catch up of revenue is recognized in the period such changes are identified.

See “Note 3, Revenue” for specific details surrounding the Company’s arrangements.

Grant revenue

Grant revenueconsists of funding under cost reimbursement programs primarily from federal and non-profit foundation sources for qualified research and development activities performed by the Company. Such amounts are invoiced and recorded as revenue as grant-funded activities are performed, with any advance funding recorded as deferred revenue until the activities are performed.

Leases

The Company determines if an arrangement is a lease at inception. Lease right-of-use assets represent the Company's right to use an underlying asset for the lease term and lease liabilities represent the Company's obligation to make lease payments arising from the lease. For operating leases with an initial term greater than 12 months, the Company recognizes operating lease right-of-use assets and operating lease liabilities based on the present value of lease payments over the lease term at the commencement date. Operating lease right-of-use assets are comprised of the lease liability plus any lease payments made and excludes lease incentives. Lease terms include options to renew or terminate the lease when the Company is reasonably certain that the renewal option will be exercised or when it is reasonably certain that the termination option will not be exercised. For the Company's operating leases, if the interest rate used to determine the present value of future lease payments is not readily determinable, the Company estimates its incremental borrowing rate as the discount rate for the lease. The Company's incremental borrowing rate is estimated to approximate the interest rate on a collateralized basis with similar terms and payments, and in similar economic environments. Lease expense for lease payments is recognized on a straight-line basis over the lease term. The Company has elected the practical expedient to not separate lease and non-lease components.

See “Note 11, Commitments and Contingencies” for specific details surrounding the Company’s leases.

Research and Development Costs, net

All research and development costs are expensed as incurred. Research and development costs consist primarily of salaries, employee benefits, costs associated with preclinical studies and clinical trials (including amounts paid to clinical research organizations and other professional services), pre-launch inventory, in-process research and development expenses and license agreement expenses. Payments made prior to the receipt of goods or services to be used in research and development are capitalized until the goods are received or the services are performed. The Company recognizes grants that fall within the scope of ASC 808 as contra research and

F-12

Arcturus Therapeutics Holdings Inc. and its Subsidiaries

Notes to Consolidated Financial Statements — Continued

development expense in the consolidated statement of operations on a systematic basis over the periods in which the entity recognizes as expenses the related costs for which the grants are intended to compensate.

The Company records accruals for estimated research and development costs, comprising payments for work performed by third party contractors, laboratories, participating clinical trial sites, and others. Some of these contractors bill monthly based on actual services performed, while others bill periodically based upon achieving certain contractual milestones. For the latter, the Company accrues the expenses as goods or services are used or rendered.

Clinical trial activities performed by third parties are accrued and expensed based upon estimates of the proportion of work completed over the life of the individual clinical trial and patient enrollment rates in accordance with agreements established with Clinical Research Organizations (“CROs”) and clinical trial sites. Estimates are determined by reviewing contracts, vendor agreements and purchase orders, and through discussions with internal clinical personnel and external service providers as to the progress or stage of completion of trials or services and the agreed-upon fee to be paid for such services.

General and Administrative Costs

General and administrative expenses consist primarily of personnel-related costs, including share-based compensation, for executives, finance, legal, human resources, business development, and other administrative and operational functions, professional fees, accounting and legal services, information technology and facility-related costs, and expenses associated with obtaining and maintaining intellectual property (“IP”). These costs relate to the operation of the business, unrelated to the research and development function, or any individual program.

Pre-Launch Inventory

Prior to obtaining initial regulatory approval for an investigational product candidate, the Company expenses costs relating to production of inventory as research and development expense in its consolidated statements of operations and comprehensive loss, in the period incurred. When the Company believes regulatory approval and subsequent commercialization of an investigational product candidate is probable, and the Company also expects future economic benefit from the sales of the investigational product candidate to be realized, it will then capitalize the costs of production as inventory.

F-13

Arcturus Therapeutics Holdings Inc. and its Subsidiaries

Notes to Consolidated Financial Statements — Continued

Share-Based Compensation

The Company records share-based compensation for equity awards granted to employees, consultants, officers and directors within general and administrative and research and development expenses on the statements of operations and comprehensive loss. Share-based compensation is recognized over the requisite service period of the individual awards using the straight-line attribution method, which generally equals the vesting period. Employees and officers’ stock options have a ten-year life and generally vest 25% on the first anniversary of the grant and in 1/36th equal installments on each monthly anniversary thereafter, such that options are fully vested on the four-year anniversary of the date of grant. The exercisability and vesting periods of equity awards granted to consultants and directors vary.

The fair value of stock options is estimated using a Black-Scholes valuation model on the date of grant. This method requires certain assumptions be used as inputs, such as the fair value of the underlying common stock, expected term of the option before exercise, expected volatility of the Company’s common stock, expected dividend yield, and a risk-free interest rate. The Company has limited historical stock option activity and therefore estimates the expected term of stock options granted using the simplified method, which represents the average of the contractual term of the stock option and its weighted-average vesting period. Through the third quarter of 2024, the Company estimated expected volatility using the historical volatility of a peer group of publicly traded companies. Beginning in the fourth quarter of 2024 and continuing into fiscal year 2025, the Company used its own historical volatility to estimate expected volatility, as it had accumulated sufficient trading history and stock price data to support the use of Company‐specific volatility. The Company has not declared or paid any dividends and does not currently expect to do so in the foreseeable future. The risk-free interest rates used are based on the implied yield currently available in United States Treasury securities at maturity with a term equivalent to the expected term of the stock options. The effect of forfeited or cancelled awards is recorded when the forfeiture or cancellation occurs.

Statement of Cash Flows

The following table provides a reconciliation of cash and cash equivalents and restricted cash reported within the consolidated balance sheets to the total of such amounts shown in the consolidated statement of cash flows:

As of December 31,

Income Tax Expense

Income taxes are accounted for using an asset and liability approach that requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the financial reporting basis and the tax basis of the Company’s assets and liabilities at the applicable tax rates, along with net operating loss and tax credit carryovers. The Company records a valuation allowance against its deferred tax assets to reduce the net carrying value to an amount that it believes is more likely than not to be realized. Management has considered estimated taxable income and ongoing prudent and feasible tax planning strategies in assessing the amount of the valuation allowance. Based upon the weight of available evidence, which includes the Company’s historical operating performance and limited potential to utilize tax attribute carryforwards, the Company has determined that total deferred tax assets should be fully offset by a valuation allowance. When the Company establishes or reduces the valuation allowance against its deferred tax assets, its provision for income taxes will increase or decrease, respectively, in the period such determination is made.

The Company is required to file federal and state income tax returns in the United States and various other state jurisdictions. The Company also files income tax returns in the foreign countries in which it operates. The preparation of these income tax returns requires the Company to interpret the applicable tax laws and regulations in effect in such jurisdictions, which could affect the amount of tax paid by the Company.

Additionally, the Company follows an accounting standard addressing the accounting for uncertainty in income taxes that prescribes rules for recognition, measurement, and classification in the consolidated financial statements of tax positions taken or expected to be taken in a tax return.

F-14

Arcturus Therapeutics Holdings Inc. and its Subsidiaries

Notes to Consolidated Financial Statements — Continued

Net Loss per Share

Basic net loss per share is calculated by dividing the net loss by the weighted-average number of shares of common stock outstanding for the period, without consideration for common stock equivalents. Diluted net loss per share is calculated by dividing the net loss by the weighted-average number of shares of common stock and dilutive common stock equivalents outstanding for the period determined using the treasury-stock method. Dilutive shares of common stock for the years ended December 31, 2025, 2024 and 2023 were comprised of stock options and restricted stock units.

No dividends were declared or paid during the reporting periods.

Recently Adopted Accounting Pronouncements

In November 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures, which requires public entities to disclose information about their reportable segments’ significant expenses and other segment items on an interim and annual basis. Public entities with a single reportable segment are required to apply the disclosure requirements in ASU 2023-07, as well as all existing segment disclosures and reconciliation requirements in ASC 280 on an interim and annual basis. The Company adopted ASU 2023-07 for annual reporting periods beginning January 1, 2024 and interim reporting periods beginning January 1, 2025. The adoption of ASU 2023-07 had no significant impact on our financial statement disclosures. See “Note 12, Segment Information” for further information.

In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740) - Improvements to Income Tax Disclosures. The new standard requires a company to expand its existing income tax disclosures, specifically related to the rate reconciliation and income taxes paid. The Company adopted ASU 2023-09 prospectively beginning in fiscal year 2025. See “Note 10, Income Taxes” for further information.

Recently Issued Accounting Standards Not Yet Adopted

From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies and adopted by the Company as of the specified effective date. The Company believes that the impact of recently issued standards that are not yet effective will not have a material impact on the consolidated financial statements and disclosures.

In November 2024, the FASB issued ASU 2024-03, Income Statement–Reporting Comprehensive Income–Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses, which requires public entities to disclose specified information about certain costs and expenses on an interim and annual basis. ASU 2024-03 is effective for annual reporting periods beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027, with early adoption permitted. The Company is currently evaluating the impact that adoption of ASU 2024-03 will have on the financial statement disclosures.

NOTE 3. Revenue

The Company has entered into license agreements and collaborative research and development arrangements with pharmaceutical and biotechnology companies, as well as consulting, related technology transfer, product revenue and government grant agreements. Under these arrangements, the Company is entitled to receive license fees, consulting fees, product fees, technological transfer fees, upfront payments, milestone payments if and when certain research and development milestones, technology transfer milestones or success-based milestones are achieved, royalties on approved product sales and reimbursement for research and development activities. The Company’s costs of performing these services are included within research and development expenses. The Company’s milestone payments are typically defined by achievement of certain preclinical, clinical, and commercial success criteria. Preclinical milestones may include in vivo proof of concept in disease animal models, lead candidate identification, and completion of IND-enabling toxicology studies. Clinical milestones may, for example, include successful enrollment of the first patient in or completion of Phase 1, 2 and 3 clinical trials, and commercial milestones are often tiered based on net or aggregate sale amounts. The Company cannot guarantee the achievement of these milestones due to risks associated with preclinical and clinical activities required for development of nucleic acid medicine-based therapeutics and vaccines.

F-15

Arcturus Therapeutics Holdings Inc. and its Subsidiaries

Notes to Consolidated Financial Statements — Continued

The following table presents changes in the balances of receivables and contract liabilities related to revenue generating agreements during the year ended December 31, 2025:

(in thousands) December 31, 2024 Additions Deductions December 31, 2025

Contract Assets:

Contract Liabilities:

During the year ended December 31, 2025, the Company recognized $26.4 million in revenue from the deferred revenue balance as of December 31, 2024.

The following table summarizes the Company’s revenue for the periods indicated. Approximately $67.1million, $138.4 million and $154.9 million of total revenue represents revenue derived from foreign countries for the years ended December 31, 2025, 2024 and 2023, respectively.

For the Year Ended December 31,

Collaboration revenue:

Grant revenue:

Gates Foundation $ 1,574 $ — $ —

Accounts receivable is comprised of the following as of December 31, 2025 and 2024:

December 31,

Billed accounts receivable $ 1,957 $ 1,472

Total accounts receivable $ 5,564 $ 3,974

Billed accounts receivable represent amounts invoiced under the Company’s collaboration and reimbursement arrangements that remain outstanding. Unbilled accounts receivable represent reimbursable costs incurred or revenue recognized for which invoices have not yet been issued as of the balance sheet date in accordance with contractual billing terms. Substantially all unbilled accounts receivable are expected to be billed and collected within 12 months.

The following paragraphs provide information regarding the nature and purpose of the Company’s most significant revenue arrangements.

CSL Seqirus

On November 1, 2022, the Company entered into a Collaboration and License Agreement (as amended, the “CSL Collaboration Agreement”) with Seqirus, Inc., a part of CSL Limited (“CSL Seqirus”), for the global exclusive rights to research, develop, manufacture, and commercialize vaccines. Under the terms of the CSL Collaboration Agreement, the Company provides CSL Seqirus with an exclusive global license to its mRNA technology (including STARR®) and LUNAR® lipid-mediated delivery, along with mRNA drug substance and drug product manufacturing processes. CSL Seqirus will lead the development and commercialization of vaccines under the collaboration. The collaboration plans to advance vaccines against SARS-CoV-2 (COVID-19), influenza, pandemic preparedness as well as three other infectious diseases. In September 2024, our COVID-19 vaccine

F-16

Arcturus Therapeutics Holdings Inc. and its Subsidiaries

Notes to Consolidated Financial Statements — Continued

KOSTAIVE® became the world’s first approved and commercially available self-amplifying RNA (sa-mRNA) vaccine.

The Company received a $200.0 million upfront payment and is eligible to receive over $1.3 billion in development milestones if all products are registered in the licensed fields and is entitled to potentially receive up to $3.0 billion in commercial milestones based on “net sales” of vaccines in the various fields. In addition, the Company is eligible to receive a 40% net profit share for COVID-19 vaccine products and up to low double-digit royalties for vaccines for pandemic preparedness and against seasonal influenza as well as three other infectious disease pathogens.

In evaluating the CSL Collaboration Agreement in accordance with ASC 606, the Company concluded that CSL Seqirus is a customer. The Company identified all promised goods/services within the CSL Collaboration Agreement, and when combining certain promised goods/services, the Company concluded that there are five distinct performance obligations. The nature of the performance obligations consists of the delivery of the vaccine license, research and development services for COVID-19 and non-COVID-19 vaccines and regulatory activities for COVID-19 vaccines. For each performance obligation, the Company estimated the standalone selling price based on 1) in the case of the license, the fair value using costs to recreate plus margin method and 2) in the case of research and development services and regulatory activities, cost plus margin for estimated full-time equivalent (“FTE”) costs, direct costs including laboratory supplies, contractors, and other out-of-pocket expenses for research and development services and regulatory activities.

As of December 31, 2025, the transaction price primarily consisted of upfront consideration received and milestones achieved. Additional variable consideration was not included in the transaction price at December 31, 2025 because the Company could not conclude that it is probable that including the variable consideration will not result in a significant revenue reversal.

The Company allocated the transaction price to the performance obligations in proportion to their standalone selling price. The vaccine license was recognized at the point in time it was transferred in 2022. The research and development and regulatory activities performance obligations are recognized over a period of time based on the percentage of services rendered using the input method, meaning actual costs incurred divided by total costs budgeted to satisfy the performance obligation. Any consideration related to sales-based royalties will be recognized when the amounts are probable of non-reversal, provided that the reported sales are reliably measurable and the Company has no remaining promised goods/services, as they are constrained and therefore have also been excluded from the transaction price. The revenue recognized during 2025 relates to the license delivered, milestones achieved and research and development and manufacturing services performed through December 31, 2025.

Total deferred revenue as of December 31, 2025 and 2024 for the CSL Collaboration Agreement was $6.2 million and $30.7 million, respectively.

During 2023, the Company entered into an amendment to the CSL Collaboration Agreement, pursuant to which the Company agreed to sponsor and conduct a Phase 1 clinical study in the influenza field. As part of the amendment, the Company received $17.5 million from CSL Seqirus. The amendment also provides for up to $1.5 million in additional payments which are achievable upon meeting certain clinical milestones relating to the Phase 1 clinical study in the influenza field. The Company previously concluded that the expansion of research and development support services under the CSL Collaboration Agreement represented an option that was not a material right. Therefore, the Company concluded the promise to sponsor and conduct the Phase 1 clinical study is a separate contract and the sole performance obligation under the new arrangement. During the period ended December 31, 2025, the Company recognized $3.2 million related to the performance obligation, which was fully satisfied during the period.

In March 2024, the Company entered into an amendment to the CSL Collaboration Agreement, pursuant to which the parties agreed to, among other things, adjust (i) the development plans for certain product candidates, (ii) various development milestones related to such product candidates, and (iii) provisions of the CSL Collaboration related to distributors, and (iv) proprietary payment calculations related to the foregoing.

BARDA Grant

In August 2022, the Company entered into a cost reimbursement contract (the “BARDA Contract”) with the Biomedical Advanced Research and Development Authority ("BARDA"), a division of the Office of the Assistant Secretary for Preparedness and Response (ASPR) within the U.S. Department of Health and Human

F-17

Arcturus Therapeutics Holdings Inc. and its Subsidiaries

Notes to Consolidated Financial Statements — Continued

Services (HHS) for an award of up to $63.2 million for the development of a pandemic influenza vaccine using the Company's STARR® self-amplifying mRNA vaccine platform technology. The Company earns grant revenue for performing tasks under the agreement.

The Company determined that the BARDA Contract is not in the scope of ASC 808 or ASC 606. Applying International Accounting Standards No. 20 ("IAS 20"), Accounting for Government Grants and Disclosure of Government Assistance, by analogy, the Company recognizes grant revenue from the reimbursement of direct out-of-pocket expenses, overhead allocations and fringe benefits for research costs associated with the grant. The costs associated with these reimbursements are reflected as a component of research and development expense in the Company’s condensed consolidated statements of operations and comprehensive loss.

The Company recognized $13.2 million and $13.9 million of grant revenue during the years ended December 31, 2025 and 2024, respectively, which is included in revenue on the Company's consolidated statements of operations. As of December 31, 2025, the remaining available funding net of revenue earned was $26.7 million.

Gates Foundation

During the year ended December 31, 2025, the Company recognized $1.6 million of grant revenue related to cost reimbursement under two grants awarded by the Gates Foundation.

The grants support development of (i) a therapeutic HPV vaccine candidate and (ii) durability assessments of self-amplifying mRNA COVID-19 vaccine platforms. Grant funding is conditional upon achievement of defined milestones and submission of periodic progress and financial reports. Revenue is recognized as qualifying costs, including employee FTE labor and related expenses, are incurred in accordance with the terms of each agreement.

Unspent or uncommitted amounts remain deferred until the associated performance obligations are satisfied. As of December 31, 2025, deferred grant revenue related to these agreements totaled $2.1 million.

NOTE 4. Fair Value Measurements

The Company establishes the fair value of its assets and liabilities using the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The Company established a fair value hierarchy based on the inputs used to measure fair value.

The three levels of the fair value hierarchy are as follows:

Level 1: Quoted prices in active markets for identical assets or liabilities.

Level 2: Inputs, other than the quoted prices in active markets, that are observable either directly or indirectly.

Level 3: Unobservable inputs in which little or no market data exists and are therefore determined using estimates and assumptions developed by the Company, which reflect those that a market participant would use.

The Company's assets measured at fair value on a recurring basis consisted of money market funds. As of December 31, 2025, the Company's had money market funds with a fair value of $229.1 million, which were classified within Level 1 of the fair value hierarchy. The fair value of these financial instruments was measured based on quoted prices.

F-18

Arcturus Therapeutics Holdings Inc. and its Subsidiaries

Notes to Consolidated Financial Statements — Continued

NOTE 5. Accrued Liabilities Detail

Accrued liabilities consisted of the following:

December 31,

Cystic Fibrosis Foundation liability 6,394 7,443

Current portion of operating lease liability 4,214 3,552

Accrued facilities costs 1,400 —

Vinbiocare contractual liabilities — 2,421

Other accrued research and development expenses 3,772 9,102

NOTE 6. Property and Equipment, Net

Property and equipment, net consisted of the following:

December 31,

Office equipment and furniture 604 703

Less accumulated depreciation and amortization (12,491 ) (11,811 )

Property and equipment, net $ 6,736 $ 9,531

Depreciation and amortization expense was $3.0 million, $3.5 million and $3.0 million for the years ended December 31, 2025, 2024 and 2023, respectively. Construction in progress is primarily comprised of research equipment not yet placed in service.

NOTE 7. Debt

Wells Fargo Credit Agreement

The Company’s wholly-owned subsidiary, Arcturus Therapeutics, Inc. (“Arcturus Therapeutics”) entered into a credit agreement with Wells Fargo Bank on April 21, 2023, and amended on June 26, 2024, whereby Wells Fargo will make a $50.0 million revolving credit line available to the Company (the “Loan”) and each draw on the Loan evidenced by a revolving line of credit note (the “Note”). On June 26, 2024, the parties entered into Amendment No. 1 to the Wells Fargo Loan, whereby the term was extended by one year to April 2026.

Borrowings under the agreement will bear interest at a rate of 1.00% above either the Daily Simple SOFR or Term SOFR (as such terms are defined in the Note), with “SOFR” being the rate per annum equal to the secured overnight financing rate as administered by the Federal Reserve Bank of New York. If an Event of Default (as defined in the agreement) occurs, then all Loans shall bear interest at a rate equal to 2.00% above the interest rate applicable immediately prior to the occurrence of the Event of Default.

The term of the agreement was originally two years, with an option for one-year renewals subject to Wells Fargo approval and Arcturus Therapeutics furnishing to Wells Fargo a non-refundable commitment fee equal to 0.25% of the Loan amount for each such renewal. There is no penalty for terminating the facility prior to the maturity date of the Note. As collateral, the Company has agreed to pledge $55.0 million in cash to be held in the Company’s securities accounts with Wells Fargo Securities, LLC, an affiliate of Wells Fargo, pursuant to a security agreement.

In December 2025, the Company terminated the credit agreement and related security agreement. No amounts were outstanding under the Loan at the time of termination. As a result, $55.0 million of cash previously pledged as collateral was released and is no longer classified as restricted cash as of December 31, 2025.

F-19

Arcturus Therapeutics Holdings Inc. and its Subsidiaries

Notes to Consolidated Financial Statements — Continued

NOTE 8. Stockholders’ Equity

Net Loss Per Share

Potentially dilutive securities that were not included in the calculation of diluted net loss per share for the year ended December 31, 2025 and 2024 as they were anti-dilutive totaled 0.6 million and 1.4 million, respectively. Potentially dilutive securities that were not included in the calculation of diluted earnings per share for the year ended December 31, 2023 as they were anti-dilutive totaled 0.8 million.

Sales Agreement

On December 23, 2022, the Company entered into a Controlled Equity OfferingSM Sales Agreement, which was amended on August 7, 2023 (as amended, the “Sales Agreement”) with Cantor Fitzgerald & Co. (“Cantor”),Wells Fargo Securities, LLC (“Wells Fargo Securities”), and William Blair & Company, L.L.C. (“William Blair”) relating to shares of the Company's common stock. In accordance with the terms of the Sales Agreement, the Company may offer and sell shares of its common stock having an aggregate offering price of up to $200 million from time to time through Cantor, Wells Fargo Securities, or William Blair, each acting as the Company's sales agent.

During the three months ended December 31, 2025, the Company sold 1,179,201 shares of its common stock pursuant to the Sales Agreement at a weighted‐average price of $10.38 per share, resulting in gross proceeds of approximately $12.2 million. After deducting offering costs of $0.5 million, the Company received net proceeds of approximately $11.7 million from these sales. In December 2025, the Company filed, and subsequently had declared effective, a replacement shelf registration statement on Form S‐3, which replaced the prior registration statement and continues to support the Sales Agreement.

NOTE 9. Share-Based Compensation

In June 2024 at the Company’s 2024 Annual Meeting of Stockholders (the "2024 Annual Meeting"), the stockholders of the Company approved an amendment to the Company’s 2019 Omnibus Equity Incentive Plan (as amended, the “2019 Plan”) which, among other things, increased the aggregate number of shares authorized for use in making awards to eligible persons under the 2019 Plan by 2,000,000 shares, for a total of up to 10,750,000 shares available for issuance. As of December 31, 2025, a total of 903,396 shares remain available for future issuance under the 2019 Plan, subject to the terms of the 2019 Plan.

In October 2021, the Company adopted the 2021 Inducement Equity Incentive Plan which covers the award of up to 1,000,000 shares of common stock (the “2021 Plan”) effective as of October 15, 2021. Approval of the Company’s stockholders is not required as a condition to the effectiveness of the 2021 Plan for so long as the plan is in compliance with applicable Nasdaq inducement plan rules. In April 2022, the compensation committee of the Company’s board of directors approved a proposal to reduce the total number of shares available for future issuance under the 2021 Plan to 130,000. Pursuant to the terms of the plan, shares underlying awards that are forfeited, cancelled, or terminated without issuance are returned to the share reserve. As of December 31, 2025, a total of 162,164 shares remain available for future issuance under the 2021 Plan, subject to the terms of the 2021 Plan.

Share Options

The following table presents the weighted-average assumptions used in the Black-Scholes valuation model by the Company in calculating the fair value of stock options granted:

For the Year Ended December 31,

Expected dividend yield — % — % — %

Grant date weighted average fair value $ 11.81 $ 22.62 $ 18.87

F-20

ARCT US Equity

ARCT · 10-K · period ended 2025-12-31

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

Item 7A. Quantitative and Qualitative Disclosures About Market Risk

Item 8. Financial Statements and Supplementary Data

Item 9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosure

Item 9A. Controls and Procedures

Item 9B. Other Information

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections

Item 10. Directors, Executive Officers and Corporate Governance

Item 11. Executive Compensation

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

Item 13. Certain Relationships and Related Transactions, and Director Independence

Item 14. Principal Accounting Fees and Services

Item 15. Exhibits, Financial Statement Schedules

Item 16. Form 10-K Summary

ARCT US Equity☆

ARCT · 10-K · period ended 2025-12-31

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

Item 7A. Quantitative and Qualitative Disclosures About Market Risk

Item 8. Financial Statements and Supplementary Data

Item 9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosure

Item 9A. Controls and Procedures

Item 9B. Other Information

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections

Item 10. Directors, Executive Officers and Corporate Governance

Item 11. Executive Compensation

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

Item 13. Certain Relationships and Related Transactions, and Director Independence

Item 14. Principal Accounting Fees and Services

Item 15. Exhibits, Financial Statement Schedules

Item 16. Form 10-K Summary

ARCT US Equity