PRTA 10-K & 10-Q changes, risk factors and insider trading

We may not generate the cash that is necessary to finance our operations in the foreseeable future. We incurred net losses of $244.1 million $122.3 million, $147.0 million and $116.9$147.0 million for the years ended December 31, 2025, 2024, 2023, and 2022,2023, respectively. As of December 31, 2024,2025, we had an accumulated deficit of $1.1$1.3 billion. We expect to continue to incur substantial losses for the foreseeable future as we:

•supportwind the Phase 3 AFFIRM-AL clinical trial for birtamimab,down the Phase 1 clinical trials for PRX012, and support the Phase 1 clinical trial for PRX019,PRX019 and potential additional clinical trials for these and other programs, including PRX123programs;

•develop and possibly commercialize our drug candidates, including birtamimab, PRX012, and PRX123candidates;

•the timing of progress, results, and costs of our clinical trials, including the Phase 3 clinical trial for birtamimab, the Phase 2 clinical trial for prasinezumab being conducted by Roche, the Phase 2b clinical trial for prasinezumab being conducted by Roche, the Phase 23 clinical trial for coramitug (formerly PRX004) being conducted by Novo Nordisk, the Phase 2 clinical trial for BMS-986446 being conducted by BMS, the Phase 1 clinical trials for PRX012, and the Phase 1 clinical trial for PRX019;

We have been, and may in the future be, adversely affected by business disruptions beyond our control, including outbreaks of epidemic, pandemic, or contagious disease, trade policies or geopolitical turmoil, earthquakes or other natural disasters, and adverse weather events, including as a result of climate change.

•Geographic regions where we operate may be affected by war, terrorism, or political instability, and our operations may be vulnerable to disruption, including disturbances to the credit and financial markets (in such region or worldwide), or to services generally, including healthcare services. For example, the Phase 3 clinical trial for birtamimab has clinical trial sites located globally, including in Israel and Eastern Europe, and operations at such clinical trial sites may be disrupted by ongoing conflicts and/or new conflicts, which could result in (i) the inability or unwillingness of study participants, site investigators or other study personnel to travel to such clinical trial sites or otherwise follow study protocols, (ii) the diversion of healthcare resources away from the conduct of clinical trials, or (iii) the complete or partial cessation of operations at such clinical trial sites.

Any one or more of these force majeure events could have a material adverse effect on our liquidity, results of operations, financial condition or business, including the progress of, and timelines for, our nonclinical and clinical development programs, and may create safety challenges for our employees and safe occupancy of our job sites, financial market volatilityvolatility, barriers to international trade, and significant macroeconomic uncertainty in global markets. Furthermore, any governmental or business actions, or any actions taken by individuals in response to any such events (including mandatory quarantines, travel restrictions, delay in operations of the U.S. FDA and comparable foreign regulatory agency, and interruptions to healthcare services), may divert healthcare resources away from the conduct of clinical trials and development programs.

Our business is increasingly dependent on critical, complex, and interdependent information technology systems to support business processes as well as internal and external communications. Despite the implementation of security measures, our internal computer systems, and those of our current and any future CROs and other contractors, consultants, and collaborators, have been subject to and remain vulnerable to damage from cyberattacks, “phishing” attacks, ransomware, computer viruses, unauthorized access, natural disasters, terrorism, war, and telecommunication or electrical failures. Attacks upon information technology systems are increasing in their frequency, levels of persistence, sophistication, and intensity, and are being conducted by sophisticated and organized groups and individuals with a wide range of motives and expertise. As a result of the COVID-19 pandemic, weWe may also face increased cybersecurity risks due to our reliance on internet technology and the number of our employees who are working remotely, which may create additional opportunities for cybercriminals to exploit vulnerabilities. Furthermore, because the techniques used to obtain unauthorized access to or to sabotage systems change frequently and often are not recognized until launched against a target, we may be unable to anticipate these techniques or implement adequate preventative measures. We may also experience security breaches that may remain undetected for an extended period. Any breakdown, malicious intrusion, or computer virus could result in the impairment of key business processes or breach of data security, which could result in a material disruption of our development programs and cause interruptions in our business operations, whether due to a loss of our trade secrets or other intellectual property or lead to unauthorized disclosure of personal data of our employees, third parties with which we do business, clinical trial participants, or others. For example, the loss of clinical trial data from completed or future clinical trials could result in delays in our regulatory approval efforts and significantly increase our costs to recover or reproduce the data. In addition, such a breach may require notification to governmental agencies, the media, or individuals pursuant to applicable data privacy and security law and regulations. Such an event could have an adverse effect on our business, financial condition, or results of operations.

Compliance with these and any other applicable privacy and data security laws and regulations is a rigorous and time-intensive process, and we may be required to substantially amend existing procedures and policies or put in place additional procedures and policies to ensure compliance with privacy and data protection rules and requirements. These changes could adversely impact our business by increasing operational and compliance costs or impact business practices. Further, there is a risk that the amended policies and procedures will not be implemented correctly or that individuals within the business will not be fully compliant with the new procedures. If we fail to comply with any such laws or regulations, we may face significant litigation, government investigations, fines and penalties as well as reputational damage which could adversely affect our business, operations, financial condition and prospects. Furthermore, the laws are not consistent, and compliance in the event of a widespread data breach is costly. In addition, states are constantly adopting new laws or amending existing laws, requiring attention to frequently changing regulatory requirements. For example, the California Consumer Privacy Act (the “CCPA”) went into effect January 1, 2020. The CCPA,, among other things, imposes new data privacy obligations on covered companies and provides expanded privacy rights to California residents, including the right to access, delete, and opt out of certain disclosures of their information. The CCPA provides for civil penalties for violations, as well as a private right of action with statutory damages for certain data breaches, which may increase the frequency and likelihood of data breach litigation. Although the law includes limited exceptions for health-related information, including clinical trial data, such exceptions may not apply to all of our operations and processing activities. Further, the California Privacy Rights Act (the “CPRA”) imposes additional data protection obligations on covered businesses, including additional consumer rights processes, limitations on data uses, audit requirements for higher risk data, and opt outs for certain uses of sensitive data. It also creates a California data protection agency authorized to issue substantive regulations and could result in increased privacy and information security enforcement. The majority of the provisions went into effect on January 1, 2023, and additional compliance investment and potential business process changes may be required. Although the CCPA currently exempts certain health-related information, including clinical trial data, the CCPA and the amendments under the CPRA may increase our compliance costs and potential liability.

Multiple states have followed California to legislate comprehensive privacy laws with data privacy rights. For example, Virginia passed the Virginia Consumer Data Protection Act, which went into effect on January 1, 2023, and affords consumers similar rights to the CCPA, along with additional rights, such as the right to opt-out of processing for profiling and targeted advertising purposes. Additionally, the Colorado Privacy ActAct, and Connecticut Personal Data Privacy and Online Monitoring Act went into effect on July 1, 2023.Act. While these new laws generally include exemptions for HIPAA-covered and clinical trial data, they impact the overall privacy landscape. Several other states have followed suit and passed similar legislation which will go into effect in the coming years. Further, additional privacy laws that are similar in nature have been proposed in other states and at the federal level and, if passed, such laws may have potentially conflicting requirements that would make compliance challenging.

There is no assurance that the results of the Phase 3 clinical trial for birtamimab, the Phase 2 clinical trial for prasinezumab, the Phase 2b clinical trial for prasinezumab, the Phase 23 clinical trial for coramitug, the Phase 2 clinical trial for BMS-986446, the Phase 1 clinical trials for PRX012, and the Phase 1 clinical trial for PRX019 will support further development of these drug candidates. In addition, we currently do not, and may never, have any other drug candidates in clinical trials, and we have not identified drug candidates for many of our research programs.

We cannot predict whether we, or our partners (as applicable), will encounter problems with the Phase 3 clinical trial for birtamimab, the Phase 2 clinical trial for prasinezumab, the Phase 2b clinical trial for prasinezumab, the Phase 23 clinical trial for coramitug, the Phase 2 clinical trial for BMS-986446, the Phase 1 clinical trials for PRX012, the Phase 1 clinical trial for PRX019, or any other future clinical trials that will cause us or any regulatory authority to delay, suspend or terminate those clinical trials or delay the analysis of data derived from them. A number of events, including any of the following, could delay the completion of our ongoing or planned clinical trials and negatively impact our ability to obtain regulatory approval for, and to market and sell, a particular drug candidate:

We are dependent upon Roche with respect to further development of prasinezumab. Under the terms of our collaboration with Roche, Roche is responsible for that further development, including the conduct of the ongoing Phase 2 and Phase 2b3 clinical trialstrial and any future clinical trial of that drug candidate.

•the data collected from clinical trials of our drug candidates may not be sufficient to support the submission of ana NDABiologics License Application (“BLA”) or a BLANew Drug Application (“NDA”) to the FDA, a Marketing Authorization Application (“MAA”) to the EMA, or similar applications to comparable regulatory authorities;

This lengthylengthy, complex approval processprocess, as well as the unpredictability of future clinical trial resultsresults, may result in our failing to obtain regulatory approval to market our drug candidates, which would significantly harm our business, results of operations, and/or growth prospects.

In addition, even if we were to obtain approval, regulatory authorities may approve any of our drug candidates for fewer or more limited indications than we request, may grant approval contingent on the performance of costly post-marketingpost-approval clinical trials,trials or other post-approval commitments or requirements, or may approve aour drug candidate with a label that does not include the labeling claims necessary or desirable for the successful commercialization of that drug candidate. Any of the foregoing scenarios could materially harm the commercial prospects for our drug candidates.

U.S. and other governments continue to propose and pass legislation designed to reduce the cost of healthcare. In the U.S., we expect that there will continue to be federal and state proposals to implement similar governmental controls. In addition, recent changes in the Medicare program and increasing emphasis on managed care in the U.S. will continue to put pressure on pharmaceutical product pricing. For example, in 2010, the U.S. Patient Protection and Affordable Care Act, as amended by the U.S. Health Care and Education Reconciliation Act (collectively, the “ACA”), was enacted. The ACA substantially changed the way healthcare is financed by both governmental and private insurers and significantly affects the pharmaceutical industry. AmongMoreover, President Biden signed into law the provisionsInflation Reduction Act (IRA) on August 16, 2022, which allows Medicare to: beginning in 2026, establish a “maximum fair price” for a fixed number of pharmaceutical and biological products covered under Medicare Parts B and D following a price negotiation process with CMS; and, beginning in 2023, penalize drug companies that raise prices for products covered under Medicare Parts B and D faster than inflation, among other reforms. It is unclear how future regulatory actions to implement the IRA, as well as the outcome of pending litigation against the IRA brought against the Department of Health and Human Services (HHS), the Secretary of HHS, CMS, and the CMS Administrator challenging the constitutionality and administrative implementation of the ACAIRA’s ofdrug importanceprice tonegotiation theprovisions, pharmaceuticalmay industryaffect areour theproducts following:and future profitability.

BirtamimabCoramitug has been granted Orphan Drug Designation by both the FDA and EMA for the treatment of ALtransthyretin (or ATTR) amyloidosis. In addition, we may seek Orphan Drug Designation for one or more of our current or future drug candidates. Regulatory authorities in some jurisdictions, including the United States and Europe, may designate drug products for relatively small patient populations as orphan drugs. Under the Orphan Drug Act, the FDA may grant orphan designation to a drug product intended to treat a rare disease or condition, defined as a disease or condition with a patient population of fewer than 200,000 in the United States. In the United States, Orphan Drug Designation entitles a party to financial incentives such as opportunities for grant funding towards clinical trial costs, tax advantages and user-fee waivers. Orphan Drug Designation does not convey any advantage in, or shorten the duration of, the regulatory review and licensure process.

Birtamimab, for the treatment of AL amyloidosis, and PRX012 and PRX123, eachBMS-986446, for the treatment of Alzheimer’s disease, have eachhas been granted Fast Track Designation by the FDA. In addition, we may seek Fast Track designation for one or more of our future drug candidates. If a drug candidate is intended for the treatment of a serious condition and demonstrates the potential to address an unmet medical need for this condition, the sponsor may apply for FDA Fast Track designation for a particular indication. We may seek Fast Track designation for our drug candidates, but there is no assurance that the FDA will grant this status to any of our drug candidates. The FDA has broad discretion whether or not to grant Fast Track designation, and even if we consider a particular drug candidate to be eligible for this designation, there is no assurance that it will be granted by the FDA. Even if we do receive Fast Track designation, we may not experience a faster review or approval compared to other, non-expedited FDA procedures, and receiving a Fast Track designation does not provide assurance of ultimate FDA approval. In addition, the FDA may withdraw Fast Track designation if it believes that the designation is no longer supported by data from our applicable clinical development program. Marketing applications filed by sponsors of products granted Fast Track designation may qualify for priority review under FDA policies and procedures, but Fast Track designation does not assure any such review or ultimate marketing approval by the FDA.

We are incorporated in Ireland and maintain subsidiaries or offices in Ireland and the U.S. We are able to achieve a low average tax rate through the performance of certain functions and ownership of certain assets in tax-efficient jurisdictions, together with intra-group service agreements. However, changes in tax laws or interpretations thereof in any of these jurisdictions could adversely affect our ability to do so in the future. Taxing authorities, such as the IRS and the Irish Revenue Commissioners (“Irish Revenue”), actively audit and otherwise challenge these types of arrangements, and have done so in our industry. We are subject to reviews and audits by the IRS, Irish Revenue and other taxing authorities from time to time, and the IRS, Irish Revenue or other taxing authorities may challenge our structure and inter-group arrangements. The Company’s U.S. subsidiaries are currently under examination by the IRS for the tax year 2021. Responding to or defending against challenges from taxing authorities may be expensive and time consuming, and may divert management’s time and focus away from operating our business. We cannot predict whether and when taxing authorities will conduct an audit, challenge our tax structure or the cost involved in responding to any such audit or challenge. If we are unsuccessful, we may be required to pay taxes for prior periods, interest, fines or penalties, and may be obligated to pay increased taxes in the future, all of which could have an adverse effect on our business, financial condition, results of operations, and/or growth prospects. In addition to the impact of changes in tax laws, our provision for income tax can be materially impacted, for example, by the geographical mix of our profits and losses, changes in our business, such as internal restructuring and acquisitions, changes and accounting guidance and other regulatory, legislative or judicial developments changes in tax rates, tax audit determinations, changes in our uncertain tax positions, changes in our intent and capacity to permanently reinvest foreign earnings, changes to our transfer pricing practices, tax deductions attributed to equity compensation and changes in our need for a valuation allowance for deferred tax assets.

Under current law, we are treated as a foreign corporation for U.S. federal tax purposes. However, changes to the U.S. Internal Revenue Code, U.S. Treasury Regulations or other IRS guidance thereunder could adversely affect our status as a foreign corporation or otherwise affect our effective tax rate. For example, in 2017 the United States enacted tax reform that contained significant changes to corporate taxation, including a provision that requires capitalization and amortization of research and development costs over five years for tax years beginning after December 31, 2021. In addition, the Irish Government, Irish Revenue, U.S. Congress, the IRS, the Organization for Economic Co-operation and Development (“OECD”), and other governments and agencies in jurisdictions where we do business have recently focused on issues related to the taxation of multinational corporations, including the OECD’s Global Anti-Base Erosion Model Rules (Pillar Two), which apply a 15% global minimum tax rate on a jurisdiction-by-jurisdiction basis to groups with turnover of not less than €750 million in at least two of the four prior fiscal years. Pillar Two has been implemented into Irish law with effect for periods beginning on or after December 31, 2023. As a result of Pillar Two or other policy changes, whether at national or supranational level, the tax laws in Ireland, the U.S., and other countries in which we do business could change on a prospective or retroactive basis, and any such changes could have an adverse effect on our business, financial condition, results of operations, and/or growth prospects.

A transfer of our ordinary shares (i) by a seller who holds shares outside of DTC to any buyer, or (ii) by a seller who holds the shares through DTC to a buyer who holds the acquired shares outside of DTC, may be subject to Irish stamp duty.duty, subject to the availability of a relief or exemption. Payment of any Irish stamp duty is generally a legal obligation of the transferee.

Fueled by our deep scientific expertise built over decades of research, we are advancing a pipeline of therapeutic candidates for a number of indications and novel targets for which our ability to integrate scientific insights around neurological dysfunction and the biology of misfolded proteins can be leveraged. Our wholly-owned programs include birtamimab for the potential treatment of AL amyloidosis, and a portfolio of programs for the potential treatment of Alzheimer’s disease including PRX012, which targets amyloid beta (Aβ), and PRX123, a novel dual Aβ-tau vaccine. Our partneredThese programs include prasinezumab for the potential treatment of Parkinson’s disease and other related synucleinopathies that targets alpha-synuclein in collaboration with Roche. In addition, we have partnered BMS-986446 (formerly PRX005) for the potential treatment for Alzheimer’s disease that targets tau and PRX019 for the potential treatment of neurodegenerative diseases with an undisclosed target in two separate license agreements with Bristol Myers Squibb (BMS). We are also entitled to certain potential milestone payments pursuant to our share purchase agreement with Novo Nordisk pertaining to our ATTR amyloidosis business (inclusive of coramitug, formerly PRX004). Our wholly-owned and unpartnered portfolio includes clinical and preclinical-stage programs that we are exploring strategic interest to further develop.

Significant judgment is required to apply the authoritative accounting guidance at the outset of a collaboration arrangement, and over time. Our Collaboration Agreement with BMS and our License Agreement with Roche containcontained multiple performance obligations. In the identification of performance obligations, there is judgment involved in identifying the promised goods or services in the collaboration agreement, determining whether these are distinct in the context of the contract, and determining if these represent a performance obligation to a customer. These determinations are highly subjective and can differ between arrangement based on specific contractual terms. The identified performance obligations will impact most significantly the timing of revenue recognition, and is a point-in-time assessment performed at the outset of a collaboration arrangement. We account for the individual performance obligations separately if they are distinct. Factors considered in the determination of whether the license performance obligations are distinct included, among other things, the research and development capabilities of each of BMS and Roche and their respective sublicense rights, and for the remaining performance obligations the fact that they are not proprietary and can be and have been provided by other vendors. The transaction price is allocated to the separate performance obligation on a relative standalone selling price basis.

At the inception of each arrangement that includes developmental, regulatory or commercial milestone payments, we evaluate whether achieving the milestones is considered probable and estimate the amount to be included in the transaction price using the most likely amount method, which includes judgment. If it is probable that a significant revenue reversal would not occur, the value of the associated milestone (such as a regulatory submission by Prothena) is included in the transaction price. Milestone payments that are not within our control, such as approvals from regulators or where attainment of the specified event is dependent on the development activities of a third party, are not considered probable of being achieved until those approvals are received or the specified event occurs. In general, we consider such milestone payments as variable consideration with constraint and therefore we recognize the revenue from such milestone payments as collaboration revenue at the point in time when we can conclude it is probable that a significant revenue reversal will not occur in future periods.

Collaboration revenue from BMS increasedwas $43.8$9.6 million for the year ended December 31, 2025, compared to $135.1 million for the year ended December 31, 2024, a decrease of $125.5 million compared to the prior year. Collaboration revenue for the year ended December 31, 2023.2025 was related to the partial performance of our PRX019 Phase 1 Clinical Trial Obligation. Collaboration revenue from BMS for 2024 included recognition of $110.1 million from the PRX019 Global License Agreement and related development services and $25.0 million was related to BMS’s material rights for the US Rights and Global Rights for the TDP-43 Collaboration Target that expired unexercised as a result of the expiration of the research term of the Collaboration Agreement. Collaboration revenue from BMS for 2023 included recognition of $91.3 million from the Tau Global License Agreement and related development services. See Note 7, “Significant Agreements” to the Consolidated Financial Statements regarding the Collaboration Agreement with BMS for more information.

Total operating expenses consist of research and development (“R&D”) expenses, general and administrative (“G&A”) expenses.expenses, and restructuring costs. Our operating expenses were $289.7$224.3 million and $282.4$289.7 million for the years ended December 31, 2024,2025, and 2023,2024, respectively.

Our research activities are aimed at developing new drug products. Our development activities involve the translation of our research into potential new drugs. Our R&D expenses primarily consist of personnel costs and related expenses, including share-based compensation and external costs associated with clinical activities and drug development related to our drug programs, including birtamimab, BMS-986446 (PRX005), PRX012, PRX123, PRX019 and preclinical activities related to our discovery programs. We also incurred wind down costs for programs that we are no longer advancing in clinical development, including birtamimab and PRX012.

Our R&D expense increaseddecreased by $1.9$87.7 million for the year ended December 31, 2024,2025, compared to the prior year. The increasedecrease for the year ended December 31, 2024,2025, was primarily due to higherlower clinical trial expenses primarily related to the PRX012 andwind birtamimabdown, programs, higherlower personnel expenses; offset in part byand lower manufacturing expense and lower other R&Dconsulting expenses.

The following table sets forth the R&D expenses for our major programs (specifically, any active programprograms with successful first dosing in a Phase 1 clinical trial and have material expenditures in the periods presented), which were birtamimab, prasinezumab, coramitug, BMS-986446 (PRX005), PRX012, PRX019PRX019, and other R&D expenses for the years ended December 31, 2024,2025, and 20232024, (in thousands):

(32) Other R&D is comprised primarily of preclinical development and discovery programs that have not progressed to first patient dosing in a Phase 1 clinical trial andtrial, close out costs for programs that we are no longer advancing.advancing, and immaterial costs incurred on ongoing partnered programs.

Our G&A expenses increaseddecreased by $5.4$7.8 million, for the year ended December 31, 2024,2025, compared to the prior year primarily due to higherlower personnel expense.and consulting expenses.

Other income (expense),expense, net for the year ended December 31, 2024,2025, was primarily foreign exchange losses from transactions with vendors denominated in euros.

TheProvision benefit fromfor income taxes decreasedincreased by $6.8$49.9 million for the year ended December 31, 2024,2025, compared to the same period in the prior year. The decline in benefit from income taxes for the year ended December 31, 2024, compared to the prior year, was primarily due to recording a lowervaluation increaseallowance infor the federal deferred tax assetsassets, relatedmainly relating to Sectionshare-based 174compensation and R&D Capitalization.expenditure capitalized in previous years.

The tax provisions for all periods presented primarily reflect U.S. federal taxes associated with recurring profits attributable to intercompany services that our U.S. subsidiary performs for the Company. No tax benefit has been recorded related to tax losses recognized in Ireland or the U.S. and any deferred tax assets for those losses are offset by a valuation allowance.

As of December 31, 2024,2025, we had $471.4$307.5 million in cash and cash equivalents. Based on our current business plans, we believe that our existing cash and cash equivalents at December 31, 20242025 are sufficient to meet our obligations for at least the next twelve months. To operate beyond such period, or if we elect to increase our spending on research and development programs significantly above current long-term plans or enter into potential licenses and/or other acquisitions of complementary technologies, products or companies, we may need additional capital. Additionally, in order to develop and obtain regulatory approval for our potential products we will need to raise substantial additional capital. We expect to continue to finance future capital needs that exceed our existing cash and cash equivalents, payments pursuant to our agreements with Roche, BMS, and Novo Nordisk, and, to the extent necessary, other collaboration agreements with corporate partners, or other arrangements, and through proceeds from public or private equity or debt financings, and loans, including pursuant to the Amended Distribution Agreement (See Note 8, “Shareholders’ Equity” to theour Consolidated Financial Statements for more information). We cannot assume that such additional financings will be available on acceptable terms, if at all, and such financings may only be available on terms dilutive to our shareholders.

The adequacy of our cash resources depends on many assumptions, including assumptions with respect to our expenses. These assumptions may prove to be wrong, and we could use our available capital resources sooner than we currently expect. Because of the numerous risks and uncertainties associated with the development and commercialization of our product candidates, we are unable to estimate the amounts of increased capital outlays and operating expenses associated with completing the development of our product candidates. Our future capital requirements will depend on numerous factors, including, without limitation, the timing of initiation, progress, results and costs of our clinical trials; the results of our research and nonclinical studies; the costs of clinical manufacturing and of establishing commercial manufacturing arrangements; the costs of preparing, filing and prosecuting patent applications and maintaining, enforcing and defending intellectual property-related claims; the costs and timing of capital asset purchases; our ability to establish research collaborations, strategic collaborations, licensing or other arrangements; the costs to satisfy our obligations under current and potential future collaborations; the costs of any in-licensing transactions; and the timing, receipt, and amount of revenues or royalties, if any, from any approved drug candidates.

Net cash used in operating activities was $150.1$163.6 million for the year ended December 31, 2024,2025, which was primarily due to ongoing research and development activities andactivities, general and administrative expenses to support those activities for a total of $289.7 million in operating expenses (adjusted to exclude non-cash charges offor approximatelyshare-based $40.2compensation millionexpense) and payments related to our restructuring activities, partially offset by $80.0 million option exercise payment from BMS, interest income on investments of $25.8 million, and cash from collection of accounts receivable of $5.2 million.investments.

Net cash used in investing activities was $0.3$138 millionthousand for the year ended December 31, 2024,2025, which primarily consisted of expenditures to purchase property and equipment.

Cash Provided by (Used in) Financing Activities

Net cash providedused byin financing activities was $1.6$139 millionthousand for the year ended December 31, 2024,2025, primarilywhich from proceeds from issuancesconsisted of ordinaryexpenditures sharesrelated uponto exercisesour ofat-the-market stock options of $1.9 million.offering.

Refer to “Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations — Liquidity and Capital Resources” in our 2024 and 2023 Annual Report on Form 10-K for a discussion of the cash flows for the years ended December 31, 20232024 and 2022.2023, respectively.

Our contractual obligations as of December 31, 2024,2025, consisted of minimum cash payments under operating leases of $12.1$9.1 million, purchase obligations of $12.7$3.1 million (of which $1.8$2.7 million is included in current liabilities), obligations under our restructuring plan of $13.3 million (of which all of it is included in current liabilities), and contractual obligations under license agreements of $0.3$50 million (of which nil is included in current liabilities).thousand. Purchase obligations consist of non-cancelable purchase commitments to suppliers. Operating leases represent our future minimum rental commitments under our non-cancelable operating leases. For additional information regarding the timing for our contractual obligations see Note 6, “Commitments and Contingencies” to our Consolidated Financial Statements.

In October 2022, we entered into a noncancelable operating sublease to lease approximately 31,157 square feet of office and laboratory space in Brisbane, California. We are obligated to make lease payments totaling approximately $14.9 million over the lease term, which expires on September 30, 2028, unless terminated earlier. Of this obligation, approximately $12.0$9.0 million remains outstanding as of December 31, 2024.2025 The following is a summary of our contractual obligations as of December 31, 2025 (in thousands):

We may not generate the cash that is necessary to finance our operations in the foreseeable future. We incurred net income of $32.7$14.1 million for the threesix months ended MarchJune 31,30, 2026, and net losses of $244.1 million and $122.3 million, and $147.0 million for the years ended December 31, 2025, 2024, and 2023, respectively. As of MarchJune 31,30, 2026, we had an accumulated deficit of $1.3 billion. We expect to continue to incur substantial losses for the foreseeable future as we:

As of MarchJune 31,30, 2026, we had cash and cash equivalents of $329.5$288.2 million. The majority of such cash is held in accounts at U.S. banking institutions that we believe are of high quality. Cash held in depository accounts may exceed the $250,000 Federal Deposit Insurance Corporation insurance limits. If such banking institutions were to fail, we could lose all or a portion of those amounts held in excess of such insurance limitations. Although we believe, based on our current business plans, that our existing cash and cash equivalents will be sufficient to meet our obligations for at least the next twelve months, we anticipate that we will require additional capital in order to continue the research and development, and eventual commercialization, of our drug candidates. Our future capital requirements will depend on many factors that are currently unknown to us, including, without limitation:

•the timing of progress, results, and costs of our clinical trials, including the Phase 3 clinical trial for prasinezumab being conducted by Roche, the Phase 3 clinical trial for coramitug (formerly PRX004) being conducted by Novo Nordisk, the Phase 2 clinical trial for moponetug (formerly BMS-986446/PRX005) being conducted by BMS, and the Phase 1 clinical trial for PRX019;

There is no assurance that the results of the Phase 3 clinical trial for prasinezumab, the Phase 3 clinical trial for coramitug, the Phase 2 clinical trial for BMS-986446,moponetug, and the Phase 1 clinical trial for PRX019 will support further development of these drug candidates. In addition, we currently do not, and may never, have any other drug candidates in clinical trials, and we have not identified drug candidates for many of our research programs.

We cannot predict whether we, or our partners (as applicable), will encounter problems with the Phase 3 clinical trial for prasinezumab, the Phase 3 clinical trial for coramitug, the Phase 2 clinical trial for BMS-986446,moponetug, the Phase 1 clinical trial for PRX019, or any other future clinical trials that will cause us or any regulatory authority to delay, suspend or terminate those clinical trials or delay the analysis of data derived from them. A number of events, including any of the following, could delay the completion of our ongoing or planned clinical trials and negatively impact our ability to obtain regulatory approval for, and to market and sell, a particular drug candidate:

We are dependent upon BMS with respect to further development of BMS-986446,moponetug, including the Phase 2 clinical trial and any future clinical trial of that drug candidate.

BMS-986446,Moponetug, for the treatment of Alzheimer’s disease, hasand coramitug, for the treatment of ATTR amyloidosis, have been granted Fast Track Designation by the FDA. In addition, we may seek Fast Track designation for one or more of our future drug candidates. If a drug candidate is intended for the treatment of a serious condition and demonstrates the potential to address an unmet medical need for this condition, the sponsor may apply for FDA Fast Track designation for a particular indication. We may seek Fast Track designation for our drug candidates, but there is no assurance that the FDA will grant this status to any of our drug candidates. The FDA has broad discretion whether or not to grant Fast Track designation, and even if we consider a particular drug candidate to be eligible for this designation, there is no assurance that it will be granted by the FDA. Even if we do receive Fast Track designation, we may not experience a faster review or approval compared to other, non-expedited FDA procedures, and receiving a Fast Track designation does not provide assurance of ultimate FDA approval. In addition, the FDA may withdraw Fast Track designation if it believes that the designation is no longer supported by data from our applicable clinical development program. Marketing applications filed by sponsors of products granted Fast Track designation may qualify for priority review under FDA policies and procedures, but Fast Track designation does not assure any such review or ultimate marketing approval by the FDA.

We are dependent on BMS, and its third-party manufacturers if applicable, to manufacture clinical supplies of BMS-986446.moponetug.

If disputes over intellectual property that we have licensed prevent or impair our ability to maintain our current licensing arrangements on acceptable terms, we may be unable to successfully develop and commercialize the affected drug candidates. We are generally also subject to all of the same risks with respect to protection of intellectual property that we license as we are for intellectual property that we own, which are described below. If we or our licensors fail to adequately protect this intellectual property, our ability to commercialize our products could suffer.

As with any publicly traded company, your percentage ownership in us may be diluted in the future because of equity issuances for acquisitions, capital raising transactions, or otherwise. We may need to raise additional capital in the future. If we are able to raise additional capital, we may issue equity or convertible debt instruments, which may severely dilute your ownership interest in us. In addition, we intend to continue to grant option awards to our directors, officers and employees, which would dilute your ownership stake in us. As of MarchJune 31,30, 2026, the number of ordinary shares available for issuance pursuant to outstanding and future equity awards under our equity plans was 16,500,684.16,381,847.

We are subject to the reporting and other obligations under the U.S. Securities Exchange Act of 1934, as amended, including the requirements of Section 404 of the U.S. Sarbanes-Oxley Act,Act (“SOX”), which require annual management assessments of the effectiveness of our internal control over financial reporting. In addition, under Section 404(b) of the U.S. Sarbanes-Oxley Act,SOX, if we are either an “accelerated filer” or “large accelerated filer,” our independent registered public accounting firm must attest to the effectiveness of our internal control over financial reporting. The rules governing the standards that must be met for management to assess our internal control over financial reporting are complex and require significant documentation, testing and possible remediation to meet the detailed standards under the rules. During the course of its testing, our management may identify material weaknesses or deficiencies which may not be remedied in time to meet the deadline imposed by the Sarbanes-Oxley Act.SOX. These reporting and other obligations place significant demands on our management and administrative and operational resources, including accounting resources.

Our management is responsible for establishing and maintaining adequate internal control over financial reporting. Our internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of our financial statements for external purposes in accordance with accounting principles generally accepted in the U.S. During the course of our review and testing of our internal controls, we have identified, and may identify in the future, deficiencies and may be unable to remediate them before we must provide the required reports. Furthermore, if we have a material weakness in our internal controls over financial reporting, we may not detect errors on a timely basis and our consolidated financial statements may be materially misstated. We, or our independent registered public accounting firm (if required), may not be able to conclude on an ongoing basis that we have effective internal control over financial reporting, which could harm our operating results, cause investors to lose confidence in our reported financial information and cause the trading price of our stockordinary shares to fall.

We are incorporated in Ireland and maintain subsidiaries or offices in Ireland and the U.S. We are able to achieve a low average tax rate through the performance of certain functions and ownership of certain assets in tax-efficient jurisdictions, together with intra-group service agreements. However, changes in tax laws or interpretations thereof in any of these jurisdictions could adversely affect our ability to do so in the future. Taxing authorities, such as the IRS and the Irish Revenue Commissioners (“Irish Revenue”), actively audit and otherwise challenge these types of arrangements, and have done so in our industry. We are subject to reviews and audits by the IRS, Irish Revenue and other taxing authorities from time to time, and the IRS, Irish Revenue or other taxing authorities may challenge our structure and inter-group arrangements. Responding to or defending against challenges from taxing authorities may be expensive and time consuming, and may divert management’s time and focus away from operating our business. We cannot predict whether and when taxing authorities will conduct an audit, challenge our tax structure or the cost involved in responding to any such audit or challenge. If we are unsuccessful, we may be required to pay taxes for prior periods, interest, fines or penalties, and may be obligated to pay increased taxes in the future, all of which could have an adverse effect on our business, financial condition, results of operations, and/or growth prospects. In addition to the impact of changes in tax laws, our provision for income tax can be materially impacted, for example, by the geographical mix of our profits and losses, changes in our business, such as internal restructuring and acquisitions, changes andin accounting guidance and other regulatory, legislativelegislative, or judicial developmentsdevelopments, changes in tax rates, tax audit determinations, changes in our uncertain tax positions, changes in our intent and capacity to permanently reinvest foreign earnings, changes to our transfer pricing practices, tax deductions attributed to equity compensationcompensation, and changes in our need for a valuation allowance for deferred tax assets.

Ireland’s Finance Act 2025 introduced a new exemption from Irish stamp duty (the “Market Capitalization Exemption”) under section 86B of the Stamp Duties Act for transfers of shares in certain Irish incorporated companies where: (i) those shares are admitted to trading on a regulated market or multilateral trading facility (within the meaning of Directive 2014/65/EU of the European Parliament and of the Council of 15 May 2014 on markets in financial instruments and amending Directive 2002/92/EC and Directive 2011/61/EU) or a market located outside the European Union that is equivalent to a regulated market or multilateral trading facility; (ii) the closing market capitalization of the issuer is below the specified threshold of €1 billion on December 1 of the preceding year; and (iii) a valid notification has been made to the Irish Revenue Commissioners for the relevant year. FutureWe have obtained the Market Capitalization Exemption for any transfers of our shares through December 31, 2026. Additionally, future transfers of our ordinary shares may be eligible for this exemption, subject to compliance with applicable notification requirements and other conditions under the Stamp Duties Act. ThereHowever, there can be no assurance that we will qualify for this exemption in any particular year, or that the exemption will continue to be available, as eligibility depends on market capitalization thresholds, timely notification to the Irish Revenue CommissionersCommissioners, and other relevant conditions.

In December 2024, topline results were announced from the Phase 2b clinical trial (PADOVA) conducted by partner Roche investigating prasinezumab in 586 people with early-stage Parkinson’s disease, treated for a minimum of 18 months while on stable symptomatic treatment. Prasinezumab showed potential clinical effect in the primary endpoint of time to confirmed motor progression, as assessed by ≥5 point increase in Movement Disorder Society – Unified Parkinson’s Disease Rating Scale (“MDS-UPDRS”) Part III score from baseline, with a HR=0.84 [0.69-1.01] and p=0.0657. The effect of prasinezumab was more pronounced in a pre-specified analysis in the population treated with levodopa (75% of participants), HR=0.79 [0.63-0.99] and nominal p=0.0431. Pre-specified supplementary covariate-adjusted analyses of these endpoints demonstrated nominally significant effects on the primary endpoint (HR=0.81 [0.67-0.98]; nominal p=0.0334) and in the levodopa subgroup (HR=0.76 [0.61-0.95]; nominal p=0.0175). Covariates used for adjustment: medication at baseline, H&Y stage, DaT-SPECT, age, sex, baseline dependent parameter. Consistent positive trends across multiple secondary and exploratory endpoints were also observed. Prasinezumab continues to be well tolerated and no new safety signals were observed in the study. In June 2026, Roche published the results from the Phase 2b PADOVA trial in The Lancet, a leading peer-reviewed medical journal. In March 2026, Roche presented an analysis from the ongoing PADOVA open-label extension (OLE) study at the International Conference on Alzheimer’s and Parkinson’s Diseases and Related Neurological Disorders (“AD/PD 2026”). Longer term data from the PADOVA OLE study in early-stage PD showed a sustained effect of prasinezumab in slowing Parkinson’s progression on top of effective symptomatic therapies. The totality of the evidence suggests a possible clinical benefit of prasinezumab and informed the initiation of the Phase 3 PARAISO study.

BMS-986446Moponetug (formerly BMS-986446/PRX005) for the Potential Treatment of Alzheimer’s Disease

BMS-986446Moponetug is designed to be a best-in-class anti-tau antibody that specifically binds with high affinity the R1, R2, and R3 repeats within the microtubule binding region (“MTBR”) of tau and targets both 3R and 4R tau isoforms. MTBR-tau has been shown in preclinical studies to be involved in the pathological spread of tau. Neurofibrillary tangles composed of misfolded tau proteins, along with amyloid beta plaques, are pathological hallmarks of Alzheimer’s disease. Cell-to-cell transmission of pathogenic extracellular tau and the accumulation of pathogenic tau also correlate with the progression of symptomatology and clinical decline in patients with Alzheimer’s disease. Recent publications suggest that during the course of Alzheimer’s disease progression, tau appears to spread throughout the brain via synaptically-connected pathways; this propagation of pathology is thought to be mediated by tau “seeds” containing the MTBR of tau. Additionally, it has been recently reported that the presence of MTBR fragments in cerebrospinal fluid correlate with dementia stages and tau tangles in Alzheimer’s disease to a higher degree than fragments of other tau regions. In preclinical research, antibodies targeting this region of tau were superior in blocking tau uptake and neurotoxicity, which has been associated with efficacy in relevant animal models. In these preclinical models, BMS-986446moponetug demonstrated significant reduction of intraneuronal tau pathology and progression protection against behavioral deficit in a tau transgenic mouse model and complete blockade of neuronal tau internalization in vitro.

Clinical Development Program for BMS-986446

In October 2025, we announced that Bristol Myers Squibb obtained Fast Track designation from the U.S. FDA for BMS-986446moponetug for the treatment of Alzheimer’s disease. The FDA’s Fast Track designation program is designed to expedite the development and review of drugs intended to treat a serious condition with evidence demonstrating the potential to address an unmet medical need.

In the first quarter of 2024, BMS advanced the anti-tau program BMS-986446moponetug with the initiation of a Phase 2 TargetTau-1 clinical trial (NCT06268886). This is a randomized, double-blind, placebo-controlled, global, Phase 2 clinical trial designed to evaluate the efficacy, safety, and tolerability of BMS-986446,moponetug, an anti-MTBR tau monoclonal antibody, in approximately 310 participants with early Alzheimer's disease. Participants will be randomized into one of three treatment arms including placebo, BMS-986446moponetug Dose A, and BMS-986446moponetug Dose B. The primary outcome measure is change from baseline to week 76 in brain tau deposition as measured by tau positron emission tomography (PET). Secondary endpoints include change from baseline to week 76 in Clinical Dementia Rating Scale Sum of Boxes (CDR-SB) score and in the integrated Alzheimer’s Disease Rating Scale (iADRS) score.

In this first-in-human, randomized, placebo controlled, single ascending dose (“SAD”) clinical trial, healthy volunteers (n=19) were enrolled into three BMS-986446moponetug dose level cohorts (low, medium or high dose) and randomized in a 3:1 drug to placebo ratio. Trial participants received a single dose of BMS-986446moponetug or placebo intravenously (“IV”) and were followed for up to two months. The results of the trial found all three dose level cohorts of BMS-986446moponetug to be generally safe and well tolerated, meeting the Phase 1 SAD trial primary objective. None of the treatment emergent adverse events (“TEAE”) were serious. No clinically relevant changes were observed in other safety parameters. BMS-986446Moponetug also met key pharmacokinetic (“PK”) and immunogenicity secondary endpoints. Plasma drug concentrations of BMS-986446moponetug increased in a dose-proportional manner. Furthermore, BMS-986446moponetug exposure in cerebrospinal fluid (“CSF”) was measured in the high dose cohort and based on the robust exposure of BMS-986446moponetug in the CSF (day 29 CSF:Plasma ratio=0.2%), substantial target engagement is expected in the CNS. BMS-986446Moponetug had a desirable immunogenicity profile with no persistent BMS-986446-inducedmoponetug-induced antidrug antibodies (“ADA”s) observed.

A multiple ascending dose (MAD) portion of the Phase 1 clinical trial was ongoing at the time BMS acquired the global rights to the program and control of the Phase 1 trial. All program updates going forward, including results from ongoing and any future BMS-986446moponetug clinical trials, will be reported by BMS.

In 2025, BMS completed a Phase 1 clinical trial to assess drug levels, tolerability and absolute biological availability of single subcutaneous dose of BMS-986446moponetug in healthy participants. This was a Phase 1, randomized, open-label, parallel, single-dose clinical trial to assess the pharmacokinetics, tolerability, and absolute bioavailability of subcutaneous administration of BMS-986446,moponetug, an anti-MTBR tau monoclonal antibody, in approximately 46 healthy participants.

In July 2021, we entered into an exclusive US license agreement for BMS-986446moponetug and we received an associated option exercise fee of $80 million. In July 2023, we entered into an exclusive global license agreement for BMS-986446,moponetug, which supersedes and replaces the US license agreement in its entirety and we received an associated option exercise fee of $55 million. We are eligible to receive regulatory and sales milestone payments of up to $563 million, as well as tiered royalties on annual, worldwide net sales. In October 2025, we announced that Bristol Myers Squibb obtained Fast Track designation from the U.S. FDA for BMS-986446moponetug for the potential treatment of Alzheimer’s disease.

In November 2025, we presented a poster titled Treatment with a Cell-Internalizing CYTOPE® Targeting pTDP-43 Reduces Intraneuronal Pathology in a Mouse Model of ALS at Neuroscience 2025, hosted by the Society for Neuroscience (SfN) and subsequently presented an encore at the 36th International Symposium of ALS/MND. The scientific poster described our TDP-43 CYTOPE® developed using our new CYTOPE® technology. CYTOPE® enables precise targeting of intracellular disease pathways in the brain and periphery through an endosomal uptake and escape mechanism that preserves membrane and vesicle integrity following systemic administration. To demonstrate the potential of CYTOPE® we developed and investigated our TDP-43 CYTOPE® program in multiple preclinical models which was the basis of the scientific presentation Preclinical data from in vivo transgenic mouse model of ALS expressing human mutant TDP-43:presentation.

•TDP-43 CYTOPE® rapidly and efficiently internalized into the cytosol and colocalized with pre-formed cytosolic pTDP-43 aggregates

•TDP-43 CYTOPE® promoted significant clearance of cytosolic pTDP-43 aggregates and meaningfully reduced RNA dysregulation driven by cryptic exon inclusions, defining pathogenic features of ALS and other TDP-43 proteinopathies These results demonstrate the potential of our CYTOPE® technology as a novel modality, enabling precise targeting of intracellular disease pathways.

There were no significant changes to our critical accounting policies and estimates during the threesix months ended MarchJune 31,30, 2026, from the critical accounting policies and estimates disclosed in Management's Discussion and Analysis of Financial Condition and Results of Operations in our 2025 Form 10-K.

Except as described in Note 2 to the Condensed Consolidated Financial Statements under the heading “Recent Accounting Pronouncements”, there have been no new accounting pronouncements or changes to accounting pronouncements during the threesix months ended MarchJune 31,30, 2026, as compared to the recent accounting pronouncements described in our 2025 Form 10-K, that are of significance or potential significance to us.

Comparison of three and six months ended MarchJune 31,30, 2026 and 2025

Total revenue was $51.1$1.0 million and $2.8$4.4 million for the three months ended MarchJune 31,30, 2026 and 2025, respectively, and $52.1 million and $7.2 million for the six months ended June 30, 2026 and 2025, respectively.

Collaboration revenue was $1.0 million forand the three months ended March 31, 2026, compared to $2.8$2.0 million for the three and six months ended MarchJune 31,30, 2026, compared to $4.4 million and $7.2 million for the three and six months ended June 30, 2025. Collaboration revenue for three and six months ended MarchJune 31,30, 2026 and 2025 was related to the partial performance of our PRX019 Phase 1 Clinical Trial Obligation.

As of MarchJune 31,30, 2026, the Company has $1.6$0.6 million of deferred revenue related to the remaining performance obligations under the PRX019 Global License Agreement related to PRX019 Phase 1 Clinical Trial Obligations. See Note 7, “Significant Agreements” to the Condensed Consolidated Financial Statements regarding the Collaboration Agreement with BMS for more information.

Intellectual property revenue for the threesix months ended MarchJune 31,30, 2026, included $50.0 million in a milestone payment from Novo Nordisk for the continued advancement of coramitug in the Phase 3 CLEOPATTRA clinical trial. See Note 7, “Significant Agreements” to the Condensed Consolidated Financial Statements regarding the Novo Nordisk Share Purchase Agreement for more information. For the threesix months ended MarchJune 31,30, 2026, and 2025, license revenue included $50 thousand in each period, respectively, in license fees recognized under the License Agreement entered into on March 1, 2020, between the Company's wholly owned subsidiary, Prothena Biosciences Limited, and F. Hoffmann-La Roche Ltd.

Total operating expenses consist of research and development (“R&D”) expenses, general and administrative (“G&A”) expenses, and restructuring costs. Our operating expenses were $21.0$22.1 million and $68.4$89.0 million for the three months ended MarchJune 31,30, 2026 and 2025, respectively, and $43.2 million and $157.4 million for the six months ended June 30, 2026 and 2025, respectively.

Our R&D expense decreased by $38.2$31.7 million or (75)%78% for the three months ended MarchJune 31,30, 2026, and decreased by $69.9 million or 77% for the six months ended June 30, 2026, compared to the same periodperiods in the prior year. The decrease for the three and six months ended MarchJune 31,30, 2026, compared to the same periodperiods in the prior year, was primarily due to lower clinical trial expenses primarily related to PRX012 and birtamimab wind down, lower personnel expenses, lower manufacturing,consulting expenses and lower consultingmanufacturing expenses .expenses.

The following table sets forth the R&D expenses for our major programs (specifically, programs with successful first dosing in a Phase 1 clinical trial and that have material expenditures in the periods presented), which were birtamimab, PRX012, PRX019, and other R&D expenses for the three and six months ended MarchJune 31,30, 2026, and 2025, (in thousands):

Our G&A expenses decreased by $4.9$5.0 million or (2831)% for the three months ended MarchJune 31,30, 2026 and decreased $9.9 million or (30)% for the six months ended June 30, 2026, compared to the same periodperiods in the prior year primarily due to lower G&A consulting and lower personnel expense.expenses.

Interest income decreased by $1.9$1.2 million or (4433)% for the three months ended MarchJune 31,30, 2026 and $3.2 million or (39)% for the six months ended June 30, 2026, compared to the same periodperiods in the prior year primarily due to lower interest income from our cash and money market accounts resulting from lower cash balances and lower yields.

Other income (expense), net for the three and six months ended MarchJune 31,30, 2026, was primarily due to foreign exchange gains and losses from transactions with vendors denominated in euros.

Provision for (benefit from) Income Taxes

Provision for income taxes increaseddecreased by $1.2$44.8 million for the three months ended MarchJune 31,30, 2026, and decreased by $43.6 million for the six months ended June 30, 2026, compared to the same periodperiods in the prior year. The decrease in income tax expense for the three and six months ended June 30, 2026, compared to the same periods in the prior year, was primarily due to Section 174 R&D Capitalization tax change in the One Big Beautiful Act that was enacted on July 4, 2025 offset in part byrecording a full valuation allowance againstfor ourthe federal deferred taxestax inassets during the currentthree period.and six months ended June 30, 2025. The tax provision presented for the periodthree and six months ended MarchJune 31,30, 2026, reflects U.S. state taxes associated with recurring profits attributable to intercompany services that our U.S. subsidiary performs for the Company.

Working capital was $306.7$280.4 million as of MarchJune 31,30, 2026, an increase of $32.3$6.0 million from working capital of $274.4 million as of MarchDecember 31, 2025. This increase in working capital during the quartersix months ended MarchJune 31,30, 2026, was primarily attributable to the $50.0 million milestone payment from Novo Nordisk.

As of MarchJune 31,30, 2026, we had $329.5$288.2 million in cash and cash equivalents. Based on our current business plans, we believe that our existing cash and cash equivalents at MarchJune 31,30, 2026 are sufficient to meet our obligations for at least the next twelve months. To operate beyond such period, or if we elect to increase our spending on research and development programs significantly above current long-term plans or enter into potential licenses and/or other acquisitions of complementary technologies, products or companies, we may need additional capital. Additionally, in order to develop and obtain regulatory approval for our potential products we will need to raise substantial additional capital. We expect to continue to finance future capital needs that exceed our existing cash and cash equivalents, payments pursuant to our agreements with Roche, BMS, and Novo Nordisk, and, to the extent necessary, other collaboration agreements with corporate partners, or other arrangements, and through proceeds from public or private equity or debt financings, and loans. We cannot assume that such additional financings will be available on acceptable terms, if at all, and such financings may only be available on terms dilutive to our shareholders.

In managing our liquidity needs in Ireland, we do not rely on unrepatriated earnings as a source of funds. As of MarchJune 31,30, 2026, $224.0$230.3 million of our outstanding cash and cash equivalents related to U.S. operations are considered permanently reinvested. We do not intend to repatriate these funds. However, if these funds were repatriated back to Ireland, we would incur a withholding tax from the dividend distribution.

Net cash provided by operating activities was $28.9$3.8 million for the threesix months ended MarchJune 31,30, 2026, which was primarily due to $50$50.0 million milestone payment from Novo Nordisk, interest income, partially offset by ongoing research and development activities, general and administrative expenses to support those activities (adjusted to exclude non-cash charges for share-based compensation expense) and payments related to our restructuring activities.

Net cash used in investing activities was null$0.7 million for the threesix months ended MarchJune 31,30, 2026.2026 which consisted of expenditures to purchase property and equipment.

Net cash used in financing activities was $6.9$22.5 million for the threesix months ended MarchJune 31,30, 2026, which consisted of cash used to repurchase our ordinary shares.

ThreeSix Months Ended MarchJune 31,30, 2025

Refer to “Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations — Liquidity and Capital Resources” in our firstsecond quarter 2025 Quarterly Report on Form 10-Q for a discussion of the cash flows for the threesix months ended MarchJune 31,30, 2025.

At MarchJune 31,30, 2026, we were not a party to any off-balance sheet arrangements that have, or are reasonably likely to have, a current or future effect on our financial condition, changes in financial condition, revenue or expenses, results of operations, liquidity, capital expenditures or capital resources.

Our contractual obligations as of MarchJune 31,30, 2026, consisted of minimum cash payments under operating leases of $8.3$7.5 million, purchase obligations of $2.3$1.6 million (of which $2.0$0.2 million is included in current liabilities), cash obligations under our restructuring plan of $8.6$0.3 million (of which all of it is included in current liabilities), and contractual obligations under license agreements of $35,000. Purchase obligations consist of non-cancelable purchase commitments to suppliers. Operating leases represent our future minimum rental commitments under our non-cancelable operating leases. For additional information regarding the timing for our contractual obligations see Note 6, “Commitments and Contingencies” to Condensed Consolidated Financial Statements.

In June 2021, we entered into a lease agreement for office space in Dublin, Ireland, which commenced in August 2021 and had an initial term of one year. In addition, we entered into a lease agreement for additional office space in Dublin, Ireland, which commenced in August 2023 and had an initial term of one year. Both leases have an automatic renewal clause, pursuant to which each agreement will be extended automatically for successive periods equal to their current terms, unless each agreement is cancelled by us. In April 2026, we renewed the August 2023 lease for another one year term. The lease that commenced in August 2021 lease was not renewed and will terminateterminated pursuant to its terms on July 31, 2026. We do not consider the renewals in the lease term as we do not believe it to be reasonably certain that we will renew these leases, as our real estate needs are subject to change based on our business needs.

In October 2022, we entered into a noncancelable operating sublease to lease approximately 31,157 square feet of office and laboratory space in Brisbane, California. We are obligated to make lease payments totaling approximately $14.9 million over the lease term, which expires on September 30, 2028, unless terminated earlier. Of this obligation, approximately $8.2$7.4 million remains outstanding as of MarchJune 31,30, 2026.

The following is a summary of our contractual obligations as of MarchJune 31,30, 2026 (in thousands):

(2) As of the filing date, there were no material changes to our purchase obligations subsequent to MarchJune 31,30, 2026.

(3) Includes cash obligations under our restructuring plan. For additional information, see Note 11, “Restructuring” to our Condensed Consolidated Financial Statements. As of the filing date, there were no material changes to our cash obligations under the restructuring plan subsequent to MarchJune 31,30, 2026 other than an increase related to termination benefits of $0.8 million.2026.