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

As of December 31, 2024,2025, we had capital resources consisting of cash and cash equivalents and short-term investments of approximately $312.0$238.3 million. We expect our existing capital resources to fund our planned operating expenses into the second half of 2026.2027. However, our operating plans may change as a result of many factors currently unknown to us, and we may need to seek additional funds sooner than planned through public or private equity offerings or debt financings or other sources, such as strategic collaborations. We may also need to seek additional funds sooner than planned as result of changes in our development plans and regulatory requirements to support registration of our product candidates. Such financing may result in dilution to our stockholders, imposition of burdensome debt covenants and repayment obligations, or other restrictions that may affect our business. In addition, we may seek additional capital due to favorable market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans.

the costs associated with beingoperating as a public company;

Additional funds may not be available when we need them, on terms that are acceptable to us, or at all. Our ability to raise additional capital may be adversely impacted by potential worsening global economic conditions, macroeconomic factors, including recent and potential bank failures, increasing inflation and interest rates, funding shortages at governmental and regulatory agencies on which we rely, exchange rate fluctuations and supply chain disruptions, geopolitical conflicts, such as the war in Ukraine and hostilities in the Middle East, and disruptions to and volatility in the credit and financial markets in the United States and worldwide. If adequate funds are not available to us on a timely basis, we may be required to:

We also could be required to seek funds through arrangements with collaborators or others that may require us to relinquish rights to some of our technologies or product candidates that we would otherwise pursue on our own. We do not expect to realize revenue from sales of products or royalties from licensed products in the foreseeable future, if at all, and unless and until our product candidates are clinically tested, approved for commercialization and successfully marketed. To date, we have primarily financed our operations through the sale of equity securities and warrants to purchase our equity securities. For example, in March 2026, we entered into a sales agreement (as amended from time to time), or Sales Agreement, with TD Securities (USA) LLC, or TD Cowen, pursuant to which we may offer and sell, from time to time through TD Cowen, at our option, shares of our common stock having an aggregate offering price of up to $150 million under an at-the-market offering program. We will be required to seek additional funding in the future and currently intend to do so through public or private equity offerings or debt financings, credit or loan facilities, collaborations or a combination of one or more of these funding sources. Our ability to raise additional funds will depend on financial, economic and other factors, many of which are beyond our control. Additional funds may not be available to us on acceptable terms or at all. If we raise additional funds by issuing equity securities,securities including pursuant to sales under the Sales Agreement, our stockholders will suffer dilution and the terms of any financing may adversely affect the rights of our stockholders. In addition, as a condition to providing additional funds to us, future investors may demand, and may be granted, rights superior to those of existing stockholders. Debt financing, if available, is likely to involve restrictive covenants limiting our flexibility in conducting future business activities, and, in the event of insolvency, debt holders would be repaid before holders of our equity securities received any distribution of our corporate assets.

We are currently focused on developing product candidates to address classical complement-mediated autoimmune and neurodegenerative diseases. We seek to maintain a process of prioritization and resource allocation among our programs to balance time, risk and cost, due to the significant resources required for the development of our product candidates. Our resources are currentlyprimarily focused on advancing ANX005tanruprubart in GBS, ANX007and vonaprument in GA and ANX1502 in autoimmune diseases.GA. If sufficient funding is not available, we may not be able to complete our planned clinical trials, or on the timelines we currently anticipate, and we may need to redesign, reduce the scope of or terminate some of our programs.

Our decisions concerning the allocation of research, development, collaboration, management and financial resources toward particular product candidates or therapeutic areas may not lead to the development of any viable commercial product and may divert resources away from better opportunities. Similarly, any decision to delay, terminate or collaborate with third parties in respect of certain programs may subsequently also prove to be suboptimal and could cause us to miss valuable opportunities. If we make incorrect determinations regarding the viability or market potential of any of our programs or product candidates or misread trends in the autoimmune or neurodegenerative or pharmaceutical, biopharmaceutical or biotechnology industry, our business, financial condition and results of operations could be materially adversely affected. As a result, we may fail to capitalize on viable commercial products or profitable market opportunities, be required to forego or delay pursuit of opportunities with other product candidates or other diseases and disease pathways that may later prove to have greater commercial potential than those we choose to pursue, or relinquish valuable rights to such product candidates through collaboration, licensing or other royalty arrangements in cases in which it would have been advantageous for us to invest additional resources to retain development and commercialization rights.

Conducting a global Phase 3 program for ANX007vonaprument in patients with dry AMD with GA will be expensive and time consuming, and we may need additional capital to complete the Phase 3 clinical program and even if favorable, the FDA and comparable foreign regulatory authorities may not accept data from our Phase 3 program.

Recent regulatory engagement regarding the Phase 3 ARCHER II trial design has established a global registration path for ANX007vonaprument in the U.S. and Europe. As a result, we are conducting ARCHER II, a global sham-controlled double-masked, Phase 3 trial. The single-study program will be analyzed as two sub-studies for the U.S. in accordance with the FDA’s two-trial recommendation. The primary endpoint of ARCHER II is prevention of ≥15-letter loss of BCVA, and an objective secondary structural measure is prevention of EZ loss. Accordingly, Annexon no longer plans to conduct a second injection-controlled head-to-head Phase 3 trial. There can be no assurance that the FDA and comparable regulatory authorities will accept the data from our Phase 3 program or determine that it is sufficient to support approval.

Conducting large Phase 3 trials in multiple jurisdictions is expensive and can take many years to complete, and we cannot guarantee that clinical trials will be conducted as planned or completed timely, if at all. In addition, there are two FDA-approved therapies for GA in the United States, which may adversely impact our ability to recruit patients into our clinical trials. Our timeline and costs for ARCHER II could be substantially longer and larger than we initially planned. We may need additional capital to complete the Phase 3 clinical program for ANX007vonaprument and may not be able to raise sufficient capital in a timely manner.manner The occurrence of any such eventswhich could delay either trial,or prevent us from completing our clinical trials,trial, prevent us from seeking FDA approval of ANX007,vonaprument, if ever, and could delay or prevent commercialization of ANX007.vonaprument.

We have no products approved for sale, and severalsome of our product candidates are in early stages of clinical development. The success of our business, including our ability to finance our company and generate revenue in the future, will primarily depend on the successful development, regulatory approval and commercialization of our product candidates and, in particular, the advancement of our current clinical-stage product candidates. However, given the stage of development of our product candidates, it may be many years, if we succeed at all, before we have demonstrated the safety, purity, potency and/or efficacy of a product candidate sufficient to warrant approval for commercialization. We cannot be certain that our product candidates will receive regulatory approval or be successfully commercialized even if we receive regulatory approval.

whether we are required by the U.S. Food and Drug Administration, or the FDA, or similar foreign regulatory agencies to conduct additional clinical trials or other studies beyond those planned to support the approval and commercialization of our product candidates or any future product candidates;

We are at an early stage of clinical development of our product candidates. Our future success is dependent on our ability to successfully develop, obtain regulatory approval for and successfully commercialize our product candidates, and we may fail to do so for many reasons, including the following:

Furthermore, clinical trials must be conducted in accordance with the laws, rules and regulations, guidelines and other requirements of the FDA, the European Medicines Agency, or the EMA, and other applicable regulatory authorities outside of those jurisdictions and are subject to oversight by these regulatory authorities and institutional review boards, or IRBs, or ethics committees at the medical institutions where such clinical trials are conducted. Further, conducting global clinical trials, as we do for GBS and GA, may require that we coordinate among the legal requirements and guidelines of regulatory authorities across a number of jurisdictions, including the United States, the European Union, or the EU, and countries outside of those jurisdictions, which could require that we amend clinical trial protocols or determine not to conduct a trial in one or more jurisdictions or to run separate trials in various jurisdictions due to the inability, cost or delay in harmonizing divergent requests from such regulatory authorities, all of which could increase costs. In addition, clinical trials that are conducted in countries outside the United States and the EU may subject us to risks associated with the engagement of non-United States and non-EU CROs who are unknown to the FDA or the EMA, or the EU member states’ regulatory authorities and may have different standards of diagnosis, screening and medical care, as well as risks associated with further delays and expenses as a result of increased shipment costs (including as a result of local quality release or in-country testing of a product candidate supply produced in a different jurisdiction for our clinical trials) and political and economic risks relevant to such countries outside the United States and the EU.

If any of our product candidates successfully completes clinical trials, we plan to seek regulatory approval to market our product candidates in the United States, the European Union, or the EU, and in additional foreign countries where we believe there is a viable commercial opportunity. We have never commenced, compiled or submitted an application seeking regulatory approval to market any product candidate. We may never receive regulatory approval to market any product candidates even if such product candidates successfully complete clinical trials, which would adversely affect our viability. To obtain regulatory approval in countries outside the United States, we must comply with numerous and varying regulatory requirements of such other countries regarding safety, efficacy, chemistry, manufacturing and controls, clinical trials, commercial sales, pricing and distribution of our product candidates. We may also rely on collaborators or partners to conduct the required activities to support an application for regulatory approval and to seek approval for one or more of our product candidates. We cannot be sure that any such collaborators or partners will conduct these activities successfully or do so within the timeframe we desire. Even if we or any future collaborators or partners are successful in obtaining approval in one jurisdiction, we cannot ensure that we will obtain approval in any other jurisdictions. If we are unable to obtain approval for our product candidates in multiple jurisdictions, our revenue and results of operations could be negatively affected.

the safety and efficacy of our product as compared to other available therapies; for example, with respect to ANX007,vonaprument, physicians may prescribe or patients may prefer recently approved therapies for the treatment of GA;

We have received Orphan Drug designation for ANX005tanruprubart for the treatment of GBS and HD in the United States and for GBS in Europe, and we may seek Orphan Drug designation for certain future product candidates. We may be unable to obtain such designations or to maintain the benefits associated with Orphan Drug designation, including market exclusivity, which may cause any revenue from product sales to be reduced.

We have received Orphan Drug designation in the United States for ANX005tanruprubart for the treatment of GBS and HD and for the treatment of GBS in Europe from the European Medicines Agency, or EMA. Although we may seek Orphan product designation for some or all of our other product candidates, we may never receive such designations. Under the Orphan Drug Act, the FDA may designate a drug or biologic product as an Orphan Drug if it is intended to treat a rare disease or condition, defined as a patient population of fewer than 200,000 in the United States, or a patient population greater than 200,000 in the United States where there is no reasonable expectation that the cost of developing the drug will be recovered from sales in the United States. Orphan Drug designation must be requested before submitting a biologics license application, or BLA, or new drug application, or NDA. In the EU, the EMA’s Committee for Orphan Medicinal Products, or COMP, grants Orphan Drug designation to promote the development of products that are intended for the diagnosis, prevention or treatment of a life-threatening or chronically debilitating condition affecting not more than five in 10,000 persons in the EU. Additionally, designation is granted for products intended for the diagnosis, prevention or treatment of a life-threatening, seriously debilitating or serious and chronic condition when, without incentives, it is unlikely that sales of the drug in the EU would be sufficient to justify the necessary investment in developing the drug or biological product or where there is no satisfactory method of diagnosis, prevention or treatment, or, if such a method exists, the medicine must be of significant benefit to those affected by the condition.

The FDA has granted Fast Track designation for ANX005tanruprubart in GBS and for ANX007vonaprument in GA, and the EMA has granted PRIME designation for ANX007vonaprument in GA, and, in the future, we may seek Fast Track designation or PRIME designation for our product candidates. If a drug or biologic is intended for the treatment of a serious or life-threatening condition and the drug or biologic demonstrates the potential to address unmet medical needs for this condition, the sponsor may apply for Fast Track designation. The sponsor of a Fast Track product candidate has opportunities for more frequent interactions with the applicable FDA review team during product development and, once a BLA or NDA is submitted, the application may be eligible for priority review. A Fast Track product candidate may also be eligible for rolling review, where the FDA may consider for review sections of the BLA or NDA on a rolling basis before the complete application is submitted, if the sponsor provides a schedule for the submission of the sections of the BLA or NDA, the FDA agrees to accept sections of the BLA or NDA and determines that the schedule is acceptable, and the sponsor pays any required user fees upon submission of the first section of the BLA or NDA. The FDA has broad discretion whether or not to grant this designation.

We conduct clinical trials of our product candidates outside the United States, and plan to continue to do so. For example, we conducted our Phase 1b GBS clinical trial of ANX005tanruprubart in Bangladesh, and have completed our Phase 3 GBS clinical trial of ANX005 in patients with GBS at sitestanruprubart in Bangladesh and the Philippines. We are also conducting a global Phase 3 program for ANX007vonaprument in dry AMD with GA. The acceptance of study data from clinical trials conducted outside the United States or the applicable jurisdiction by the FDA and comparable foreign regulatory authorities may be subject to certain conditions, or may not be accepted at all.

ForIn example,particular, where data from foreign clinical trials are intended to serve as the sole basis for marketing approval in the United States, regardless of whether such trials were conducted under an IND, the FDA will not approve the application on the basis of foreign data alone unless those data are applicable to the United States population and United States medical practice, the trials were performed by clinical investigators of recognized competence and the data are considered valid without the need for an on-site inspection by the FDA or, if the FDA considers such an inspection to be necessary, the FDA is able to validate the data through an on-site inspection or other appropriate means. For trials that are conducted only at sites outside of the United States and not subject to an IND, the FDA requires the clinical trial to have been conducted in accordance with good clinical practice, or GCP, requirements, and the FDA must be able to validate the data from the clinical trial through an on-site inspection if it deems such inspection necessary. Additionally, the FDA’s clinical trial requirements, including sufficient size of patient populations and statistical powering, must be met. Many foreign regulatory bodies have similar approval requirements. In addition, foreign trials are subject to the applicable local laws of the foreign jurisdictions where the trials are conducted. There can be no assurance that the FDA, EMA or any comparable foreign regulatory authority will accept data from trials conducted outside of the United States or the applicable jurisdiction. If the FDA or any comparable foreign regulatory authority does not accept such data, it would result in the need for additional trials or the amendment of ongoing trials, which would be costly and time-consuming and delay aspects of our business plan,plan and which may result in product candidates that we may develop notor receiving approval or clearance for commercialization in the applicable jurisdiction.

To support data from clinical trials conducted in foreign jurisdictions, applicants may submit clinical evidence, clinical trials, patient registries or other sources of RWE, such as electronic health records or the collection of larger confirmatory data sets. In particular, because all of our studies to date for ANX005tanruprubart in GBS have been conducted at sites outside the United States, we have conducted a RWE study to assess comparability of disease populations in the US and ex-US using a large natural history database from IGOS. Published data from IGOS presents baseline characteristics of GBS patients in various jurisdictions and patient outcomes at certain timepoints over the course of their disease. We intendare also conducting the open-label FORWARD study in the U.S. and Europe which is designed to usebroaden Western experience with tanruprubart and anticipate initial PK, PD, biomarker and functional data in 2026. Following such data, we plan to engage with the resultsFDA with the goal of thereaching RWEalignment studyon alongour withcurrent anyand othersupplemental requesteddata package and information forsupporting the generalizability of Southeasttanruprubart Asianin Western patients tofor submission of a WesternBLA populationin as2026. partIn our discussion with the FDA, the FDA has indicated that the generalizability package may not be sufficient to support BLA approval absent additional patient data. While we expect that the inclusions of U.S. and European results from the FORWARD study will support a BLA submission in GBS, it is possible the FDA determines that our current package is not sufficient or requires us to provide additional data package in supportGBS ofpatients thethat ANX005are BLA.not However,feasible to obtain. Our inability to satisfy such additional requirements by the FDA may notresult agree thatin the currentFDA data package is sufficientfailing to acceptapprove fortanruprubart filingin a BLA and we may receive a refusal to file letter and be required to conduct additional clinical trials of ANX005 for GBS prior to resubmission of a BLA,GBS, which would resultprevent in delays in our application process and increase our expenses, and delay or preventthe commercialization of ANX005tanruprubart in GBS.GBS Even if accepted for filing byin the FDA,United anyStates, suchand BLAlimit the size of our commercial market opportunity and our potential future revenues, and could beotherwise the subject ofhave a completematerial responseadverse lettereffect rather than approval, which would increaseon our expenses and delay or prevent commercialization of ANX005 in GBS.business.

In addition, we are conducting a global registrational program of ANX007vonaprument for the treatment of dry AMD with GA. To accomplish this objective, we must obtain and maintain regulatory approvals and comply with regulatory requirements in each jurisdiction. We are in ongoing discussions with the relevant regulatory authorities. While we believe we have designed a global clinical development program that could satisfy the regulators in all of our target markets, there is no assurance that our efforts will be successful or that the various regulators will be aligned or accept the data from the Phase 3 program are sufficient to warrant approval of ANX007.vonaprument.

We currently do not have the ability to independently conduct preclinical studies or clinical trials that comply with the regulatory requirements known as good laboratory practice, or GLP,GLP requirements or GCP requirements, respectively. The FDA and regulatory authorities in other jurisdictions require us to comply with GCP requirements for conducting, monitoring, recording and reporting the results of clinical trials, in order to ensure that the data and results are scientifically credible and accurate and that the trial subjects are adequately informed of the potential risks of participating in clinical trials. We rely on medical institutions, clinical investigators, contract laboratories and other third parties, such as CROs, to conduct GLP-compliant preclinical studies and GCP-compliant clinical trials on our product candidates properly and on time. While we have agreements governing their activities, we control only certain aspects of their activities and have limited influence over their actual performance. The third parties with whom we contract for execution of our GLP-compliant preclinical studies and our GCP-compliant clinical trials play a significant role in the conduct of these studies and the subsequent collection and analysis of data. These third parties are not our employees and, except for restrictions imposed by our contracts with such third parties, we have limited ability to control the amount or timing of resources that they devote to our programs. Although we rely on these third parties to conduct our GLP-compliant preclinical studies and GCP-compliant clinical trials, we remain responsible for ensuring that each of our preclinical studies and clinical trials is conducted in accordance with its investigational plan and protocol and applicable laws and regulations, and our reliance on the CROs does not relieve us of our regulatory responsibilities.

Although a substantial amount of our effort will focus on the continued development and potential approval of our current product candidates, a key element of our strategy is to identify, develop and commercialize a portfolio of products that address classical complement-mediated autoimmune and neurodegenerative diseases. A component of our strategy is to evaluate our product candidates in multiple indications based, in part, on our evaluation of certain biomarkers in a disease area. For example, we intend to evaluate ANX005tanruprubart in neurodegenerative diseases, including amyotrophic lateral sclerosis, or ALS,ALS and Huntington’s disease, or HD; however, we are continuing to evaluate ANX005tanruprubart in these patient populations, and even if we believe we have obtained positive clinical results in patients with one of these neurodegenerative diseases, such results may not be replicated in later studies evaluating ANX005tanruprubart in patients with the same disease or across other neurodegenerative or autoimmune diseases. Even though we are currently developing a pipeline of product candidates, our development efforts may still fail to yield product candidates potentially suitable for commercialization for many reasons, including the following:

Certain alternative treatments offered by competitors may be available at lower prices and may offer greater efficacy or better safety profiles. Furthermore, currently approved products could be discovered to have application for the intended indication of our product candidates, which could give such products significant regulatory and market timing advantages over any of our product candidates. Our competitors also may obtain FDA, EMA, or other regulatory approval for their products more rapidly than we may obtain approval for ours and may obtain orphan product exclusivity from the FDA for indications our product candidates are targeting, which could result in our competitors establishing a strong market position before we are able to enter the market. For example, with respect to ANX007,vonaprument, there are two approved products for GA which may pose competition for ANX007,vonaprument, if approved. For additional information regarding our competition, see the section titled “Business—Competition” in this Annual Report on Form 10-K..

As of December 31, 2024,2025, we had 10096 full-time employees. We will need to continue to expand our managerial, operational, finance and other resources in order to manage our operations and clinical trials, continue our development activities and commercialize our product candidates or any future product candidates. Our management and personnel, systems and facilities currently in place may not be adequate to support this or any futureour growth. Our need to effectively execute our growth strategy requires that we:

successfully commercialize ANX005tanruprubart and any of our other product candidates, if approved;

Our business is susceptible to general conditions in the global economy and in the global financial markets. Global financial crises and global or regional political disruptions have caused, and could in the future cause, extreme volatility in the capital and credit markets. A severe or prolonged economic downturn, including a recession or depression, recent and potential bank failures, the current inflationary economic environment, rising interest rates, debt and equity market fluctuations, diminished liquidity and credit availability, increased unemployment rates, funding shortages at governmental and regulatory agencies on which we rely, including regulatory agencies, decreased investor and consumer confidence, supply chain challenges, natural catastrophes, the effects of climate change, regional and global conflicts and terrorist attacks or political disruption or turmoil could result in a variety of risks to our business, including weakened demand for our product candidates or any future product candidates, if approved, and our ability to raise additional capital when needed on acceptable terms, if at all. A weak or declining economy or political disruption could also strain our manufacturers or suppliers, possibly resulting in supply disruption, or cause our customers to delay making payments for our potential products. Any of the foregoing could materially and adversely affect our business, financial condition, results of operations and prospects, and we cannot anticipate all of the ways in which the political or economic climate and financial market conditions could adversely impact our business.

Patent terms may be shortened or lengthened in certain jurisdictions by, for example, terminal disclaimers, patent term adjustments, supplemental protection certificates and patent term extensions. Patent term extensionsPTEs and supplemental protection certificates, and the like, may be impacted by the regulatory process and may not significantly lengthen patent term. Non-payment or delay in payment of patent extension filing (including any patent term extension or adjustment filing) fees, whether intentional or unintentional, may also result in the loss of patent rights important to our business. Certain countries have compulsory licensing laws under which a patent owner may be compelled to grant licenses to other parties. In addition, many countries limit the enforceability of patents against other parties, including government agencies or government contractors. In these countries, the patent owner may have limited remedies, which could materially diminish the value of any patents.

Manufacturers and manufacturers’ facilities are required to comply with extensive FDA and comparable foreign regulatory authority requirements, including ensuring that quality control and manufacturing procedures conform to cGMP regulations.cGMPs. As such, we and our contract manufacturers will be subject to continual review and inspections to assess compliance with cGMPs and adherence to commitments made in any approved marketing application. Accordingly, we and others with whom we work must continue to expend time, money and effort in all areas of regulatory compliance, including manufacturing, production and quality control.

Since its enactment, there have been amendments and judicial, Congressional and executive branch challenges to certain aspects of the ACA. For example, on AugustJuly 16,4, 2022,2025, the InflationOne ReductionBig ActBeautiful ofBill 2022,Act, or IRA,the OBBBA, was signed into law, which narrowed access to ACA marketplace exchange enrollment and declined to extend the ACA enhanced advanced premium tax credits that expired at the end of 2025, which, among other things,provisions extendsin enhancedthe subsidieslaw, are anticipated to reduce the number of Americans with health insurance. The OBBBA also is expected to reduce Medicaid spending and enrollment by implementing work requirements for individualssome purchasingbeneficiaries, healthcapping insurancestate-directed coveragepayments, inreducing federal funding, and limiting provider taxes used to fund the program. Congress is considering proposed legislation intended to further reduce healthcare costs with alternatives to replace the expired ACA marketplaces through plan year 2025. The IRA also eliminates the “donut hole” under the Medicare Part D program beginning in 2025 by significantly lowering the beneficiary maximum out-of-pocket cost and creating a new manufacturer discount program.subsidies. It is unclear how these and other healthcare reform measures will impact our business.

Ensuring that our internal operations and future business arrangements with third parties comply with applicable healthcare laws and regulations will involve substantial costs. It is possible that governmental authorities will conclude that our business practices,practices such as the provision of stock options to physicians who may influence the ordering, prescribing or use of our product candidates, if approved, as compensation for consulting services, do not comply with current or future statutes, regulations, agency guidance or case law involving applicable fraud and abuse or other healthcare laws and regulations. If our operations are found to be in violation of any of the laws described above or any other governmental laws and regulations that may apply to us, we may be subject to significant penalties, including civil, criminal and administrative penalties, damages, fines, exclusion from government-funded healthcare programs, such as Medicare and Medicaid or similar programs in other countries or jurisdictions, disgorgement, imprisonment, contractual damages, reputational harm, diminished profits and the curtailment or restructuring of our operations. Further, defending against any such actions can be costly and time-consuming and may require significant personnel resources. Even if we are successful in defending against any such actions that may be brought against us, our business may be impaired.

The stock price of our common stock has been, and could in the future be, subject to substantial volatility and wide fluctuations in response to various factors, some of which are beyond our control. In particular, the stock prices for pharmaceutical, biopharmaceutical and biotechnology companies have been highly volatile as a result of extreme volatility and disruptions in the global economy, including rising inflation and interest rates, tariffs, declines in economic growth, theinternational war between Russia and Ukraineconflicts and uncertainty about economic stability, including a potential recession. These factors include those discussed in this “Risk Factors” section and others such as:

As of December 31, 2024,2025, our executive officers, directors, holders of 5% or more of our capital stock and their respective affiliates beneficially owned a majority48% of our outstanding voting stock. In addition, in our 20232023, 2024, and 20242025 financings, certain of the holders of 5% or more of our capital stock acquired pre-funded warrants to purchase shares of our common stock (which are immediately exercisable and have an exercise price of $0.001 per share) or common warrants to purchase shares of our common stock. Until exercised, the shares issuable upon the exercise of the pre-funded warrants and the common warrants are not included in the number of our outstanding shares of common stock. If such holders exercise their warrants, then the shares of our capital stock beneficially owned by our executive officers, directors, holders of 5% or more of our capital stock and their respective affiliates would increase significantly. Therefore, these stockholders will have the ability to influence us through this ownership position. These stockholders may be able to determine all matters requiring stockholder approval. For example, these stockholders may be able to control elections of directors, amendments of our organizational documents, or approval of any merger, sale of assets or other major corporate transaction. This may prevent or discourage unsolicited acquisition proposals or offers for our common stock that you may feel are in your best interest as one of our stockholders.

We may from time to time issue additional shares of common stock, and as a result, our stockholders would experience immediate dilution. In addition, as opportunities present themselves, we may enter into financing or similar arrangements in the future, including the issuance of debt securities, preferred stock or common stock. For example, in March 2024, we entered into a sales agreement with CowenTD andCowen, Companyas LLC,sales oragent, pursuant to which we sold approximately $66.7 million of shares of our common stock under an at the market offering program as of the date of this Annual Report on Form 10-K. In March 2026, we entered into a new sales agreement with TD Cowen, as sales agent, pursuant to which we may issue and sell shares of our common stock for an aggregate maximum offering price of $100.0up to $150 million under ana new at-the-market offering program under which we have sold approximately $4.5 million of shares of our common stock as of the date of this Annual Report on Form 10-K.program. In addition, in July 2022, December 2023, and June 2024, and November 2025, we closed financings which included the sale of pre-funded warrants or common warrants to purchase shares of our common stock. Until exercised, the shares issuable upon the exercise of the pre-funded warrants or the common warrants are not included in the number of our outstanding shares of common stock. If we issue common stock or securities convertible into common stock in the future, our stockholders would experience additional dilution and such dilutive impact may be difficult to compute.

Under Sections 382 and 383 of the Internal Revenue Code of 1986, as amended, or the Code, if a corporation undergoes an “ownership change,” generally defined as a greater than 50 percentage point change (by value) in its equity ownership by certain stockholders over a rolling three-year period, the corporation’s ability to use its pre-change net operating loss carryforwards, or NOLs, and other pre-change tax attributes (such as research and development tax credits) to offset its post-change income or taxes may be limited. If finalized, Treasury Regulations currently proposed under Section 382 of the Code may further limit our ability to utilize our pre-change NOLs or credits if we undergo a future ownership change.

We completed a study through December 31, 2024,2025, to determine whether an ownership change had occurred under Section 382 or 383 of the Code, and we determined that ownership changes occurred in 2011, 2014, 2020 and 2023. We have identified $0.1 million and $34.7 million of federal and state NOLs, respectively, that will expire unused due to ownership changes, and federal credits of $4.3 million that will not be able to be utilized due to ownership change limitation and excluded these amounts from deferred tax asset balances as of December 31, 2024. Federal NOLs of $367.6 million and state and local NOLs of $189.2 million are not expected to expire unutilized as a result of ownership changes identified through December 31, 2024.2025.

We are also subject to the anti-takeover provisions contained in Section 203 of the Delaware General Corporation Law.law of the State of Delaware, or DGCL. Under Section 203, a corporation may not, in general, engage in a business combination with any holder of 15% or more of its capital stock unless the holder has held the stock for three years or, among other exceptions, the board of directors has approved the transaction.

In addition, as permitted by Section 145 of the Delaware General Corporation Law,DGCL, our amended and restated bylaws and our indemnification agreements that we have entered into with our directors and officers provide that:

Our amended and restated certificate of incorporation and amended and restated bylaws provide that the Court of Chancery of the State of Delaware (or, in the event that the Court of Chancery does not have jurisdiction, the federal district court for the District of Delaware or other state courts of the State of Delaware) is the exclusive forum for any derivative action or proceeding brought on our behalf, any action asserting a claim of breach of fiduciary duty, any action asserting a claim against us arising pursuant to the Delaware General Corporation Law,DGCL, our amended and restated certificate of incorporation or our amended and restated bylaws, or any action asserting a claim against us that is governed by the internal affairs doctrine; provided that, the exclusive forum provision will not apply to suits brought to enforce any liability or duty created by the Exchange Act or any other claim for which the federal courts have exclusive jurisdiction; and provided further that, if and only if the Court of Chancery of the State of Delaware dismisses any such action for lack of subject matter jurisdiction, such action may be brought in another state or federal court sitting in the State of Delaware. Our amended and restated certificate of incorporation and amended and restated bylaws also provide that the federal district courts of the United States of America are the exclusive forum for the resolution of any complaint asserting a cause of action against us or any of our directors, officers, employees or agents and arising under the Securities Act. Nothing in our amended and restated certificate of incorporation and amended and restated bylaws precludes stockholders that assert claims under the Exchange Act from bringing such claims in state or federal court, subject to applicable law.

Cybersecurity risks and the failure to maintain the security, confidentiality, integrity, or availability of our information technology systems or data, and those maintained on our behalf, could lead to adverse consequences that materially adversely affect our business, including, without limitation, regulatory investigations or actions, a material interruption to our operations, including clinical trials, damage to our reputation and/or subject us to costs, loss of customers or sales, fines and penalties or lawsuits.

ANX1502 for Autoimmune Indications: We are advancing ANX1502,is a novel oral small molecule inhibitorinhibiting the activated form of C1s, an enzyme carried by C1q to initiate the classical complementcascade, which we believe is first-in-kind.first-in-kind and has the potential to offer the advantages of selective upstream classical complement inhibition with the convenience and flexibility of oral administration. In a Phase 1 single-ascending dose, or SAD,dose and multiple-ascending dose, or MAD,dose clinical trial in healthy volunteers designed to evaluate the safety, tolerability, pharmacokinetics, or PK,PK and pharmacodynamics, or PD, ANX1502 was generally well tolerated across cohorts with no serious adverse events, achieved target levels of active drug and showed supportive impact on a PD biomarker of complement activity that support its advancement.activity. We are evaluating aan enteric-coated tablet formulation of ANX1502 in an ongoing proof-of-conceptPOC study in patients with cold agglutinin disease, or CAD,CAD. We have observed drug levels at and exceeding the pre-defined target in fasted CAD patients. Dosing is ongoing to assessenhance PK,our PDunderstanding of ANX1502’s profile and clinicalwe efficacyplan endpointsto (e.g.,provide hemolysisan asupdate measuredupon bystudy reduction of elevated bilirubin) and data are expectedcompletion in mid-2025. Following the successful completion of the proof-of-concept study, we intend to evaluate ANX1502 in a host of diseases, including serious complement-mediated autoimmune diseases, with the aim of providing enhanced efficacy and offering convenient dosing administration for long-term treatment of chronic conditions.2026.

contract manufacturing costs to produce clinical trial materials and commercial materials to support anyour BLAplanned regulatory package submissions to theFDA FDAand other foreign regulatory agencies; and laboratory supplies and materials.

General and administrative expenses increaseddecreased by $4.7$2.9 million, or 16%,8%, for the year ended December 31, 20242025 compared to the year ended December 31, 2023. The increase was2024 primarily duedriven toby anongoing increasecorporate efficiencies and disciplined prioritization of $3.4resources resulting in a $2.6 million decrease in consulting and professional services costscosts. forIn business development, market research, and recruitment costs, an increase of $0.7 million in facilities related costs due to the expiration of a sublease agreement, and an increase inaddition, compensation and personnel-related expenses decreased by $1.2 million mainly due to the full amortization of $0.5previously granted high fair value stock options, partially offset by higher headcount. The overall decrease in general and administrative expenses was partially offset by other expenses which increased by $0.9 million due to ancloud-based increaseinfrastructure in headcount.costs.

Interest and other incomeincome, increasednet decreased by $6.4$6.2 million for the year ended December 31, 20242025 compared to the year ended December 31, 2023.2024. The increasedecrease was primarily due to higherlower average cash and investment balances and favorable interest rates.balances.

Due to our significant research and development expenditures, we have generated operating losses each year since our inception.

WeTo date, we have funded our operations primarily through the sale of equity securities.securities including, most recently, the public offering of approximately $86.3 million of common stock and pre-funded warrants. In addition, on March 30, 2026, we entered into a sales agreement with TD Cowen, or the 2026 Sales Agreement, pursuant to which we may offer and sell, from time to time through TD Cowen, at our option, shares of our common stock having an aggregate offering price of up to $150.0 million. As of December 31, 2024,2025, we had available cash and cash equivalents and short-term investments of $312.0$238.3 million and an accumulated deficit of $710.7$917.4 million.

Based upon our current operating plan, we believe that our existing cash and cash equivalents and short-term investments will enable us to fund our operating expenses and capital expenditure requirements into the second half of 2026.2027. We will require substantial additional financing to achieve our goals, and a failure to obtain this necessary capital when needed on acceptable terms, or at all, could force us to delay, limit, reduce or terminate our product development programs, commercialization efforts or other operations. We have based this estimate on assumptions that may prove to be wrong, and we could utilize our available capital resources sooner than we expect. UntilWe will be required to seek additional funding in the future until such time, if ever, as we can generate substantial product revenue, we will be required to seek additional funding in the future and currently intend to do so through public or private equity offerings or debt financings, credit or loan facilities, collaborations or a combination of one or more of these funding sources. We may also need to seek additional funds sooner than planned as result of changes in our development plans and regulatory requirements to support registration of our product candidates. Additional funds may not be available to us on acceptable terms or at all. If we fail to obtain necessary capital when needed on acceptable terms, or at all, we could be forced to delay, limit, reduce or terminate our product development programs, commercialization efforts or other operations. If we raise additional funds by issuing equity securities, our stockholders will suffer dilution and the terms of any financing may adversely affect the rights of our stockholders. In addition, as a condition to providing additional funds to us, future investors may demand, and may be granted, rights superior to those of existing stockholders. Debt financing, if available, is likely to involve restrictive covenants limiting our flexibility in conducting future business activities, and, in the event of insolvency, debt holders would be repaid before holders of our equity securities received any distribution of our corporate assets.

In June 2024, we raised net proceeds of approximately $116.8 million after deducting underwriting discounts and offering expenses through the sale of 13,001,120 shares of our common stock, par value $0.001 per sharestock at a price of $6.25 per share and pre-funded warrants to purchase an aggregate of 7,000,000 shares of common stock at a price of $6.249 per share, which equals the per share offering price for the shares of common stock less the $0.001 exercise price for each pre-funded warrant. In March 2026, we issued an aggregate of 4,499,124 shares of common stock upon the cashless exercise of pre-funded warrants to purchase 4,500,000 shares of common stock. As of the date of these consolidated financial statements, pre-funded warrants to purchase up to 2,500,000 shares of common stock remained outstanding from the 2024 Financing.

In December 2023, we raised net proceeds of approximately $117.0 million after deducting underwriting discounts and offering expenses through the sale of 25,035,000 shares of our common stock, par value $0.001 per sharestock at a price of $2.880 per share and pre-funded warrants to purchase an aggregate of 18,379,861 shares of common stock at a price of $2.879 per share, which equals the per share offering price for the shares of common stock less the $0.001 exercise price for each pre-funded warrant. We issued an aggregate of 5,243,400 and 965,427 shares of common stock upon cashless and cash exercise of these pre-funded warrants in February 2024 and April 2024, respectively.

In July 2022, we raised net proceeds of approximately $122.5 million after deducting fees and expenses through the sale of an aggregate of 9,013,834 shares of common stock, pre-funded warrants to purchase up to 24,696,206 shares of our common stock and accompanying common warrants to purchase up to 8,427,508 shares of our common stock. The offering price per share and accompanying common warrant was $3.87125 per share and the offering price per pre-funded warrant and accompanying common warrant was $3.87025 per share, which equals the per share offering price for the shares of common stock less the $0.001 exercise price for each such pre-funded warrant. The pre-funded warrants remain exercisable until exercised in full. The common warrants havehad an exercise price of $5.806875 per share andand, expireexcept as described in the next paragraph, expired on June 30, 2025. Both the pre-funded and common warrants arewere immediately exercisable, subject to beneficial ownership limitations. We issued an aggregate of 2,582,557 shares of common stock upon the cashless exercise of the pre-funded warrants in March 2023. We issued an aggregate of 19,901 and 2,739,096 shares of common stock upon the cashless exercise of the common warrants and pre-funded warrants in June 2024 and November 2024, respectively.

The following summarizes warrant activity during the yearsyear ended December 31, 2024 and 20232025:

20242026 At-the-MarketAt the Market (ATM) Program

In March 2024, we entered into a sales agreement with Cowen and Company LLC, or TD Cowen, as sales agent, or 2024 ATM program, pursuant to which we maycould issue and sell shares of our common stock for an aggregate maximum offering of $100.0 million.million under an at-the-market offering program, or 2024 ATM program. TD Cowen is entitled to compensation up to 3% of the aggregate gross proceeds for the common stock sold through the 2024 ATM program. During the year ended December 31, 2025 and 2024, we sold 9,740,824 shares and 750,000 shares of common stockstock, respectively, for net proceeds of approximately $27.4 million and $4.5 million, respectively, after deducting commissions paid to TD Cowen. As of December 31, 2024,2025, approximately $95.4$66.9 million remained available for the offer and sale of shares of common stock under the 2024 ATM program. Subsequent to December 31, 2025 and through the date of issuance of these consolidated financial statements, we sold 6,049,762 shares of common stock under the 2024 ATM for net proceeds of approximately $32.8 million, after deducting commissions paid to TD Cowen.

In August 2021, we entered into a sales agreement with TD Cowen, as sales agent, pursuant to which we maycould issue and sell shares of our common stock for an aggregate maximum offering of $100.0 million under an at-the-market offering program, or 2021 ATM program. TD Cowen is entitled to compensation of up to 3% of the aggregate gross proceeds forof the common stock sold through the 2021 ATM program. During the yearsyear ended December 31, 2024 and 2023,2024, we sold 7,576,067 shares and 2,646,458 shares of common stock, respectively,stock under the 2021 ATM program for net proceeds of approximately $38.4 million and $17.5 million, respectively, after deducting commissions paid to TD Cowen and other financing costs. The Form S-3 registration statement, which registered the 2021 ATM Program, expired on August 15, 2024. As a result, no shares of common stock may be sold under the 2021 ATM Program.

We may encounter substantial delays in our clinical trials or may not be able to conduct or complete our clinical trials on the timelines we expect.expect, if at all.

Actual or perceived failure to comply with applicable data protection laws, regulations, standards, contractual obligations and other requirements related to data privacy and security could lead to government enforcement actions as well as civil and criminal penalties, private litigation (including class actions), or adverse publicity and otherwise could negatively affect our results of operations and business.

We have had significant operating losses since our inception. Our net loss for the years ended December 31, 2025 and 2024 was approximately $206.7 million and $138.2 million, respectively, and our net loss for the three and six months ended MarchJune 31,30, 2026 was approximately $44.1$55.3 million.million and $99.5 million, respectively. As of MarchJune 31,30, 2026, we had an accumulated deficit of $961.5approximately million.$1.0 billion. Substantially all of our losses have resulted from expenses incurred in connection with our research and development programs and from general and administrative costs associated with our operations. We expect to continue to incur losses for the foreseeable future, and we anticipate these losses will continue as we develop our product candidates, conduct clinical trials and pursue research and development activities. Even if we achieve profitability in the future, we may not be able to sustain profitability in subsequent periods. Our prior losses, combined with expected future losses, have had and will continue to have an adverse effect on our stockholders’ equity and working capital.

As of MarchJune 31,30, 2026, we had capital resources consisting of cash and cash equivalents and short-term investments of approximately $225.0$209.2 million. We expect our existing capital resources to fund planned operating expenses into the second half of 2027.2028. However, our operating plans may change as a result of many factors currently unknown to us, and we may need to seek additional funds sooner than planned through public or private equity offerings or debt financings or other sources, such as strategic collaborations. We may also need to seek additional funds sooner than planned as result of changes in our development plans and regulatory requirements to support registration of our product candidates. Such financing may result in dilution to our stockholders, imposition of burdensome debt covenants and repayment obligations, or other restrictions that may affect our business. In addition, we may seek additional capital due to favorable market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans.

Additional funds may not be available when we need them, on terms that are acceptable to us, or at all. Our ability to raise additional capital may be adversely impacted by potential worsening global economic conditions, macroeconomic factors, including recent and potential bank failures, increasing inflation and interest rates, funding shortages at governmental and regulatory agencies on which we rely, exchange rate fluctuations and supply chain disruptions, geopolitical conflicts, such as the war in Ukraine and hostilitiesconflicts in the Middle East, and disruptions to and volatility in the credit and financial markets in the United States and worldwide. If adequate funds are not available to us on a timely basis, we may be required to:

For example, we intend to seek FDA approval of tanruprubart for the treatment of patients with GBS. Our data package is based on completed placebo-controlled studies conducted in Southeast Asia. We filed a MAA with the EMA for tanruprubart for the treatment of GBS in January 2026, and we continue to engage with EU regulators through the MAA review process. Tanruprubart has been granted orphan designation from the EMA. Tanruprubart has also been granted Fast Track and orphan drug designation for the treatment of GBS from the FDA. The currently ongoing open-label FORWARD study in the U.S. and Europe, which is designed to broaden Western experience with tanruprubart, and we anticipate initial PK, PD, biomarker and functional data in the second half of 2026 to supplement our comprehensive data package for tanruprubart in GBS. Following such data, we plan to engage with the FDA with the goal of reaching alignment on the sufficiency of our current and supplemental data package and information supporting the generalizability of tanruprubart in Western patients for submission of a BLA in 2026. In our discussions to date with the FDA, the FDA has indicated that the generalizability package may not be sufficient to support BLA approval absent additional patient data. While we expect that the inclusion of U.S. and European results from the FORWARD study will support a BLA submission in GBS, it is possible the FDA determines that our current package is not sufficient or requires us to provide additional data in GBS patients that are not feasible to obtain. Our inability to satisfy such additional requirements by the FDA may result in the FDA failing to approve tanruprubart in GBS, which would prevent the commercialization of tanruprubart in GBS in the United States, and limit the size of our commercial market opportunity and our potential future revenues, and could otherwise have a material adverse effect on our business.

To support data from clinical trials conducted in foreign jurisdictions, applicants may submit clinical evidence, clinical trials, patient registries or other sources of RWE, such as electronic health records or the collection of larger confirmatory data sets. In particular, because all of our studies to date for tanruprubart in GBS have been conducted at sites outside the United States, we conducted a RWE study to assess comparability of disease populations in the US and ex-US using a large natural history database from IGOS. Published data from IGOS presents baseline characteristics of GBS patients in various jurisdictions and patient outcomes at certain timepoints over the course of their disease. We filed a MAA with the EMA for tanruprubart for the treatment of GBS in January 2026, and we continue to engage with EU regulators through the MAA review process. Tanruprubart has been granted orphan designation from the EMA. Tanruprubart has also been granted Fast Track and orphan drug designation for the treatment of GBS from the FDA. The currently ongoing open-label U.S./EU FORWARD study in the U.S. and Europe which is designed to broaden Western experience with tanruprubart, and we anticipate initial PK, PD, biomarker and functional data in 2026 to supplement our comprehensive data package for tanruprubart in GBS. Following such data, we plan to engage with the FDA with the goal of reaching alignment on our current and supplemental data package and information supporting the generalizability of tanruprubart in Western patients for submission of a BLA in 2026. In our discussiondiscussions with the FDA, the FDA has indicated that the generalizability package may not be sufficient to support BLA approval absent additional patient data. While we expect that the inclusion of U.S. and European results from the FORWARD study will support a BLA submission in GBS, it is possible the FDA determines that our current package is not sufficient or requires us to provide additional data in GBS patients that are not feasible to obtain. Our inability to satisfy such additional requirements by the FDA may result in the FDA failing to approve tanruprubart in GBS, which would prevent the commercialization of tanruprubart in GBS in the United States, and limit the size of our commercial market opportunity and our potential future revenues, and could otherwise have a material adverse effect on our business.

Certain alternative treatments offered by competitors may be available at lower prices and may offer greater efficacy or better safety profiles. Furthermore, currently approved products could be discovered to have application for the intended indication of our product candidates, which could give such products significant regulatory and market timing advantages over any of our product candidates. Our competitors also may obtain FDA, EMA, or other regulatory approval for their products more rapidly than we may obtain approval for ours and may obtain orphan product exclusivity from the FDA for indications our product candidates are targeting, which could result in our competitors establishing a strong market position before we are able to enter the market. For example, with respect to vonaprument, there are two approved products for GA which may pose competition for vonaprument, if approved. For additional information regarding our competition, see the section titled “Business—Competition”. in our Annual Report on Form 10-K for the year ended December 31, 2025.

The availability and adequacy of coverage and reimbursement by governmental healthcare programs such as Medicare and Medicaid, private health insurers and other third-party payors are essential for most patients to be able to afford prescription medications such as our product candidates, if approved. Our ability to achieve acceptable levels of coverage and reimbursement for products by governmental authorities, private health insurers and other organizations will have an effect on our ability to successfully commercialize our product candidates. Obtaining coverage and adequate reimbursement for our products may be particularly difficult because of the higher prices often associated with drugs administered under the supervision of a physician. Even if we obtain coverage for our product candidates by a third-party payor, the resulting reimbursement payment rates may not be adequate or may require co-payments that patients find unacceptably high. For products administered under the supervision of a physician, obtaining coverage and adequate reimbursement may be particularly difficult because of the higher prices often associated with such drugs. Additionally, separate reimbursement for the product itself or the treatment or procedure in which the product is used may not be available, which may impact physician utilization. We cannot be sure that coverage and reimbursement in the United States, the EU or elsewhere will be available for our product candidates or any product that we may develop, and any reimbursement that may become available may be decreased or eliminated in the future.

Third-party payors increasingly are challenging prices charged for pharmaceutical, biopharmaceutical and biotechnology products and services, and many third-party payors may refuse to provide coverage and reimbursement for particular drugs or biologics when an equivalent generic drug, biosimilar or a less expensive therapy is available. For example, the U.S. Department of Health and Human Services, or HHS, imposes rebates on many Medicare Part B and Medicare Part D products to penalize price increases that outpace inflation on an annual basis.inflation. In addition, HHS has been empowered to negotiate the price of certain single-source drugs that have been on the market for at least 7 years and single-source biologics that have been on the market for at least 11 years covered under Medicare as part of the Medicare Drug Price Negotiation Program. Each year up to twenty (20) products will be selected by HHS for the Medicare Drug Price Negotiation Program. Products subject to the Medicare Drug Price Negotiation Program are expected to experience a significant reduction in reimbursement from the Medicare program on a per unit basis. If coverage and adequate reimbursement are not available, or are available only to limited levels, we may not be able to successfully commercialize our current and any future product candidates that we develop, which could have an adverse effect on our operating results and our overall financial condition.

As of MarchJune 31,30, 2026, we had 9392 full-time employees. We will need to continue to expand our managerial, operational, finance and other resources in order to manage our operations and clinical trials, continue our development activities and commercialize our product candidates or any future product candidates. Our management and personnel, systems and facilities currently in place may not be adequate to support our growth. Our need to effectively execute our growth strategy requires that we:

Individual states in the United States have also become increasingly active in passing legislation and implementing regulations designed to control pharmaceutical and biological product pricing, including price or patient reimbursement constraints, discounts, restrictions on certain product access and marketing cost disclosure and transparency measures, and, in some cases, designed to encourage importation from other countries and bulk purchasing. For example, on June 15, 2026, the FDA approved Colorado’s Section 804 Importation Program, or SIP, proposal to import certain drugs from Canada for specific state healthcare programs. It is unclear how this and Florida’s similar program, approved by the FDA in 2024, will be implemented and whether they will overcome potential legal, regulatory, or industry challenges in the United States and/or Canada. Legally mandated price controls on payment amounts by third-party payors or other restrictions could materially and adversely affect our business, financial condition, results of operations and prospects. In addition, regional healthcare authorities and individual hospitals are increasingly using bidding procedures to determine what pharmaceutical products and which suppliers will be included in their prescription drug and other healthcare programs. This could reduce the ultimate demand for our product candidates or put pressure on our product pricing.

As of MarchJune 31,30, 2026, our executive officers, directors, holders of 5% or more of our capital stock and their respective affiliates beneficially owned 41%47% of our outstanding voting stock. In addition, in our 2023, 2024, and 2025, financings, certain of the holders of 5% or more of our capital stock acquired pre-funded warrants to purchase shares of our common stock (which are immediately exercisable and have an exercise price of $0.001 per share) or common warrants to purchase shares of our common stock. Until exercised, the shares issuable upon the exercise of the pre-funded warrants and the common warrants are not included in the number of our outstanding shares of common stock. If such holders exercise their warrants, then the shares of our capital stock beneficially owned by our executive officers, directors, holders of 5% or more of our capital stock and their respective affiliates would increase significantly. Therefore, these stockholders will have the ability to influence us through this ownership position. These stockholders may be able to determine all matters requiring stockholder approval. For example, these stockholders may be able to control elections of directors, amendments of our organizational documents, or approval of any merger, sale of assets or other major corporate transaction. This may prevent or discourage unsolicited acquisition proposals or offers for our common stock that you may feel are in your best interest as one of our stockholders.

Our current shares outstanding and resulting market valuation do not reflect shares of our common stock issuable upon the exercise of pre-funded warrants and common warrants that are exercisable at the discretion of the holders of such warrants. If we sell shares of our common stock in the future, stockholders may experience immediate dilution. Stockholders may be unable to compute the dilutive impact of future financings.

We may from time to time issue additional shares of common stock, and as a result, our stockholders would experience immediate dilution. In addition, as opportunities present themselves, we may enter into financing or similar arrangements in the future, including the issuance of debt securities, preferred stock or common stock. For example, in March 2024, we entered into a sales agreement with TD Cowen, as sales agent, pursuant to which we sold approximately $66.7 million of shares of our common stock under an at the market offering program as of the date of this Quarterly Report on Form 10-Q. In March 2026, we entered into a new sales agreement with TD Cowen, as sales agent, pursuant to which we may issue and sell shares of our common stock for an aggregate maximum offering price of up to $150 million under a new at-the-market offering program. As of the filing date of this Quarterly Report on Form 10-Q, we had sold $32.2 million of common stock under the program. In addition, in December 2023, June 2024, and November 2025, we closed financings which included the sale of pre-funded warrants or common warrants to purchase shares of our common stock. Until exercised, the shares issuable upon the exercise of the pre-funded warrants or the common warrants are not included in the number of our outstanding shares of common stock. If we issue common stock or securities convertible into common stock in the future, our stockholders would experience additional dilution and such dilutive impact may be difficult to compute.

If our existing stockholders sell, or indicate an intention to sell, substantial amounts of our common stock in the public market, the stock price of our common stock could decline. As of MarchJune 31,30, 2026, the number of shares of our common stock outstanding was 162,501,717.174,604,198. This number does not include 35,765,79929,765,799 shares of common stock issuable upon the exercise of pre-funded warrants or 6,877,622 shares of common stock issuable upon the exercise of common warrants. On August 12, 2024, we filed a resale registration statement on Form S-3, pursuant to which, entities and trusts affiliated with Muneer Satter, a member of our board of directors, can sell up to 3,000,000 shares of common stock. Sales of a substantial number of shares of our common stock in the public market, or the perception that these sales might occur, may reduce the stock price of our common stock.

We are a biopharmaceutical company advancing the next generation platform of targeted immunotherapies aimed at complement-mediated neuroinflammatory diseases that collectively impact nearly 10 million people worldwide. Building on more than a decade of expertise stopping acute and chronic neuroinflammation at its source, we have demonstrated robust target engagement in the body, brain and eye, and clinical proof of concept in multiple diseases.

Tanruprubart is an investigational targeted immunotherapy delivered in a single infusion to rapidly halt aggressive neuroinflammation and damage in GBS, an acute, rare, neuromuscular emergency that annually affects ~150,000 people worldwide. There are currently no therapies approved by the FDA for GBS and no substantial evidence of effectiveness from the current standard of care. In the placebo-controlled Phase 3 trial, approximately 90% of GBS patients treated with tanruprubart improved by week 1 and more than twice as many treated patients achieved a normal state of health at week 26. Tanruprubart has consistently demonstrated rapid and sustained functional improvements across a comprehensive data package. We continue to engage with applicable EU and U.S. regulators to advance tanruprubart towards registration worldwide. Our Marketing Authorization Application, or MAA, filed with the European Medicines Agency, or EMA, in January 2026 for tanruprubart for the treatment of GBS is under review, and we continue to engage with EU regulators through the MAA review process. Tanruprubart has been granted orphan designation from the EMA. Tanruprubart has also been granted Fast Track and orphan drug designation for the treatment of GBS from the FDA. The currently ongoing open-label U.S./Europe FORWARD study is designed to broaden Western experience with tanruprubart, and we anticipate initial pharmacokinetics, or PK, pharmacodynamics, or PD, biomarker and functional data in 2026 to supplement our comprehensive data package for tanruprubart in GBS. Following such data, we plan to engage with the FDA with the goal of reaching alignment on our current and supplemental data package and information supporting the generalizability of tanruprubart in Western patients for submission of a biologics license application, or BLA, in 2026.

In Julythe 2025, we completed enrollment of 659 patients in ARCHER II, aongoing global, sham-controlled, double-masked Phase 3 trial.ARCHER II trial of 659 patients with GA, all eligible patients have received at least 12 months of vonaprument treatment, with masked event accrual in line with projections. ARCHER II retains strong statistical power and continues to be well-executed with a low discontinuation rate (<10%) and high compliance (>95%). We recently announced the expansion of the vonaprument Phase 3 program to add a Month 24 dual primary endpoint, complementing the current Month 15 primary endpoint, and to launch an open-label extension (OLE) study. With a dual primary endpoint strategy, ARCHER II can achieve success in protecting against vision loss at either Month 15 or Month 24, which are independent efficacy timepoints. The Month 15 primary endpoint remains on track for the fourth quarter of 2026. Upon completion of Month 24, all patients will have the option to receive monthly vonaprument treatment in the OLE study, designed to evaluate the longer-term profile of vonaprument for inclusion in the label. The primary endpointendpoints of ARCHERthis IItwo-year istrial are the gold standard for visual acuity, measuring proportion of patients with confirmed BCVA ≥15-letter loss at any two consecutive visitsvisits, measured through monthmonths 15.15 Aand secondary24. endpointSecondary isendpoints EZinclude loss,safety, whichlow isluminance avisual keyacuity anatomic measure ofand photoreceptor health and function. We plan to report topline data in the fourth quarter of 2026.integrity. We have established a global registration path with the FDA and EMA, which supports the potential of vonaprument to be the first treatment approved in both Europe and the U.S. for the protection of vision in patients with GA. The single-study program will be analyzed as two sub-studies in the U.S. in accordance with the FDA’s two-trial recommendation. Vonaprument is the first and only therapeutic candidate for the treatment of GA to receive Priority Medicine, or PRIME, designation by the EMA, which provides early and proactive support to developers of promising medicines that may offer a major therapeutic advantage over existing treatments or benefit to patients without treatment options. Vonaprument was also selected by the EMA for the Product Development Coordinator Pilot launched in July 2025 to help PRIME designation holders efficiently navigate regulatory interactions including expedited scientific advice, MAA submission readiness activities, and ad-hoc queries throughout the development program.

ANX1502 is a novel oral small molecule inhibiting the activated form of C1s, an enzyme carried by C1q to initiate the classical cascade, which we believe is first-in-kind and has the potential to offer the advantages of selective upstream classical complement inhibition with the convenience and flexibility of oral administration. In a Phase 1 single-ascending dose and multiple-ascending dose clinical trial in healthy volunteers designed to evaluate the safety, tolerability, PK and PD, ANX1502 was generally well tolerated across cohorts with no serious adverse events, achieved target levels of active drug and showed supportive impact on a PD biomarker of complement activity. We are evaluating an enteric-coated tablet formulation of ANX1502 in an ongoing POC study in patients with cold agglutinin disease, or CAD. We have observed drug levels at and exceeding the pre-defined target in fasted CAD patients. Dosing is ongoing to enhance our understanding of ANX1502’s profilecomplete and we plan to provide an update uponon the POC study completion in the second half of 2026.

We were incorporated in March 2011 and commenced operations later that year. To date, we have focused primarily on performing research and development activities, hiring personnel and raising capital to support and expand these activities. We do not have any products approved for sale, and we have not generated any revenue from product sales. We have incurred net losses each year since our inception. Our net losses were $44.1$55.3 million and $54.4$49.2 million for the three months ended MarchJune 31,30, 2026 and 2025, respectively, and $99.5 million and $103.5 million for the six months ended June 30, 2026 and 2025, respectively. As of MarchJune 31,30, 2026, we had an accumulated deficit of $961.5approximately million$1.0 billion and cash and cash equivalents and short-term investments of $225.0$209.2 million.

Comparison of the Three Months Ended MarchJune 31,30, 2026 and 2025

Research and development expenses decreasedincreased by $12.4$2.4 million, or 26%,6%, for the three months ended MarchJune 31,30, 2026 compared to the same period in 2025. The change was primarily attributable to aan decreaseincrease of $11.2$6.0 million in completed contract manufacturing activity for the tanruprubart European MAA filing as well as the vonaprument manufacturing technology transfer of vonaprument to a commercial-ready facility. Consulting and professional services expenses decreased by $1.4 million, following the MAA submission for tanruprubart in January 2026. Compensation and personnel-related expenses (including stock-based compensation) decreased by $2.4$1.3 million, reflecting lower headcount, and consulting and professional services expenses decreased by $1.9 million.headcount. In addition, direct clinical and nonclinical outside services costs increaseddecreased by $3.4$1.2 million primarily associated with the vonaprument Phase 3 ARCHER II trial in GA andpartially theoffset ongoingby higher tanruprubart FORWARD study in GBS.costs.

General and administrative expenses increased by $1.0$3.1 million, or 11%,41%, for the three months ended MarchJune 31,30, 2026 compared to the same period in 2025, primarily driven by a $1.2$2.3 million increase in consulting and professional services costs for corporate affairs activityactivities across our portfolio. In addition, compensation and personnel-related expenses were higher primarily due to stock-based compensation expense.

Interest and other income, net, decreased by $1.1$0.7 million, or 37%,27%, for the three months ended MarchJune 31,30, 2026 compared to the same period in 2025. The decrease was primarily due to lower average cash and investment balances.

To date, we have funded our operations primarily through the sale of equity securities including, most recently in November 2025, the public offering of approximately $86.3 million of shares of common stock and pre-funded warrants. In addition, on March 30, 2026, we entered into a sales agreement with TD Cowen, or the 2026 Sales Agreement,Cowen pursuant to which we may offer and sell, from time to time through TD Cowen, at our option, shares of our common stock having an aggregate offering price of up to $150.0 million. As of MarchJune 31,30, 2026, we had available cash and cash equivalents and short-term investments of $225.0$209.2 million and an accumulated deficit of $961.5approximately million.$1.0 billion.

Cash used in operating activities for the threesix months ended MarchJune 31,30, 2026 was $46.8$94.8 million, which consisted of a net loss of $44.1$99.5 million,million and a net change of $7.1$5.3 million in our operating assets and liabilities, partially offset by $4.4$10.0 million in non-cash charges. The non-cash charges consisted of stock-based compensation of $4.2$9.0 million, depreciation and amortization of $0.5$1.1 million, and a reduction in the carrying amount of right-of-use assets of $0.4$0.8 million, partially offset by accretion of discount on available-for-sale securities of $0.6$0.9 million.

Cash used in operating activities for the threesix months ended MarchJune 31,30, 2025 was $50.1$88.1 million, which consisted of a net loss of $54.4$103.5 million, partially offset by $4.1$8.0 million in non-cash charges and a net change of $0.2$7.4 million in our operating assets and liabilities. The non-cash charges consisted of stock-based compensation of $5.1$9.3 million, depreciation and amortization of $0.5$1.1 million and a reduction in the carrying amount of right-of-use assets of $0.4$0.7 million, partially offset by accretion of discount on available-for-sale securities of $1.9$3.1 million.

Cash provided by investing activities for the threesix months ended MarchJune 31,30, 20252026 was $97.6$67.0 million, which consisted of $159.5$83.0 million of proceeds from maturities of available-for-sale securities, partially offset by $61.8$15.9 million of purchases of available-for-sale securities and $0.1 million of purchases of property and equipment.

Cash provided by financing activities for the threesix months ended MarchJune 31,30, 2026 was $32.9$65.0 million, which consisted of $32.7$63.8 million of net proceeds from the aggregate issuance of common stock under our 2024 ATM program and $0.22026 ATM program and $1.3 million of net proceeds from the exercise of common stock options and employee stock purchase plan purchases.

Cash provided by financing activities for the threesix months ended MarchJune 31,30, 2025 was $0.1$0.2 million, which consisted of $0.1 million of proceeds from the exercise of common stock options.options and employee stock purchase plans.

Based upon our current operating plan, we believe that our existing cash and cash equivalents and short-term investments will enable us to fund operating expenses into the second half of 2027.2028. We will require substantial additional financing to achieve our goals, and a failure to obtain this necessary capital when needed on acceptable terms, or at all, could force us to delay, limit, reduce or terminate our product development programs, commercialization efforts or other operations. We have based this estimate on assumptions that may prove to be wrong, and we could utilize our available capital resources sooner than we expect. We will be required to seek additional funding in the future until such time, if ever, as we can generate substantial product revenue, and currently intend to do so through public or private equity offerings or debt financings, credit or loan facilities, collaborations or a combination of one or more of these funding sources. We may also need to seek additional funds sooner than planned as result of changes in our development plans and regulatory requirements to support registration of our product candidates. Additional funds may not be available to us on acceptable terms or at all. If we fail to obtain necessary capital when needed on acceptable terms, or at all, we could be forced to delay, limit, reduce or terminate our product development programs, commercialization efforts or other operations. If we raise additional funds by issuing equity securities, our stockholders will suffer dilution and the terms of any financing may adversely affect the rights of our stockholders. In addition, as a condition to providing additional funds to us, future investors may demand, and may be granted, rights superior to those of existing stockholders. Debt financing, if available, is likely to involve restrictive covenants limiting our flexibility in conducting future business activities, and, in the event of insolvency, debt holders would be repaid before holders of our equity securities received any distribution of our corporate assets.

In June 2024, we raised net proceeds of approximately $116.8 million after deducting underwriting discounts and offering expenses through the sale of 13,001,120 shares of our common stock at a price of $6.25 per share and pre-funded warrants to purchase an aggregate of 7,000,000 shares of common stock at a price of $6.249 per share, which equals the per share offering price for the shares of common stock less the $0.001 exercise price for each pre-funded warrant. In March 2026, we issued an aggregate of 4,499,124 shares of common stock upon the cashless exercise of pre-funded warrants to purchase 4,500,000 shares of common stock.

In December 2023, we raised net proceeds of approximately $117.0 million after deducting underwriting discounts and offering expenses through the sale of 25,035,000 shares of our common stock at a price of $2.880 per share and pre-funded warrants to purchase an aggregate of 18,379,861 shares of common stock at a price of $2.879 per share, which equals the per share offering price for the shares of common stock less the $0.001 exercise price for each pre-funded warrant. In March 2026, we issued an aggregate of 2,027,384 shares of common stock upon the cashless exercise of pre-funded warrants to purchase 2,027,778 shares of common stock.

In June 2025, we and holders of common warrants exercisable for 6,877,622 shares of our common stock entered into amendments to the common warrants held by such holders. The amendments extended the term of the common warrants by one year until June 30, 2026, and removed the cashless exercise option. If all such common warrants are exercised in full for cash (without regard to any applicable ownership limitations), we would receive aggregate gross proceeds of approximately $39.9 million. The remaining common warrants to purchase 1,226,993 shares of our common stock not subject to these amendments expired unexercised on June 30, 2025. On June 30, 2026, the amended common warrants to purchase 6,877,622 shares of our common stock expired unexercised.

The following summarizes warrant activity during the threesix months ended MarchJune 31,30, 2026 and 2025:

In March 2026, we entered into a sales agreement with TD Securities (USA) LLC, or TD Cowen, as sales agent, pursuant to which we may offer and sell, from time to time through TD Cowen, at our option, shares of our common stock having an aggregate offering price of up to $150.0 million, or the 2026 ATM program. We agreed to pay TD Cowen a commission of up to 3.0% of the aggregate gross proceeds for the common stock sold through the 2026 ATM program. During the threesix months ended MarchJune 31,30, 2026, no sales were made under the 2026 ATM program. Subsequent to March 31, 2026 and through the date of issuance of these interim unaudited condensed consolidated financial statements, we sold 1,305,4635,734,361 shares of common stock under the 2026 ATM program for net proceeds of approximately $8.1$31.0 million, after deducting commissions paid to TD Cowen.Cowen and other offering costs. As of June 30, 2026, approximately $117.8 million remained available under the 2026 ATM program.

In March 2024, we entered into a sales agreement with TD Cowen, as sales agent, or 2024 ATM program, pursuant to which we couldwere issuepermitted to offer and sell shares of our common stock forhaving an aggregate maximum offering price of up to $100.0 million.million, or 2024 ATM program. During the threesix months ended MarchJune 31,30, 2026, we sold 6,049,762 shares of our common stock under the 2024 ATM program for net proceeds of approximately $32.7 million, after deducting commissions paid to TD Cowen and other offering costs. No sales were made under the 2024 ATM program during the six months ended June 30, 2025. In May 2026, we terminated the 2024 ATM program. Approximately $33.3 million remained available under the 2024 ATM program,program whichat wethe terminatedtime inof Maytermination; 2026.however, no further shares of common stock may be sold under the 2024 ATM program.

During the quarter ended MarchJune 31,30, 2026, there were no material changes to our critical accounting policies or in the methodology used for estimates from those described in “Management’s Discussion and Analysis of Financial Condition and Results of Operations” included in our Annual Report on Form 10-K for the year ended December 31, 2025.