What changed in this filing

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Item 1A. Risk Factors

2026-02-23 compared with 2025-02-24 · 200 added, 167 removed, 874 unchanged (30% of the section changed)

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We expect to incur losses for at least the next several years and may never generate or maintain profits.

We are a development-stage company and we cannot assure profitability.

We expect to continue to generate operating losses for the foreseeable future.

Until we can generate substantial revenue and achieve profitability, we will need to raise additional capital to fund ongoing operations and capital needs.

We are a development-stage company and we cannot ensure profitability.

Since inception, we have incurred significant operating losses.

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Consequently, any predictions you make about our future success or viability may not be as accurate as they could be if we had a longer operating history.

In January 2026, the FDA accepted for filing our BLA seeking approval of ivonescimab in combination with chemotherapy in patients with EGFR-mutated locally advanced or metastatic non-squamous NSCLC post-TKI therapy and provided a PDUFA target action date of November 14, 2026.

The delay or denial of regulatory approval, inability to maintain regulatory approval, inability to complete post-marketing requirements, or the requirement to resubmit any marketing application with additional data or information could mean that we otherwise negatively would delay commercialization of ivonescimab and adversely impact our ability to generate revenue, our business and our operations.

Assuming we obtain marketing approval for any of our product candidates, we will need to transition from a company with a research and development focus to a company capable of supporting commercial activities or seek an appropriate partner or partners to maximize the commercial opportunity of our products with a deal structure that maximizes our opportunities for profitability.

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In addition, our product candidates, if approved, may not achieve commercial success.

Our commercial revenues, if any, will be derived from sales of products that we are not planning to have commercially available for several years, if at all.

Additional financing may not be available to us on acceptable terms, or at all.

Our commercial revenues, if any, will be derived from sales of products that may not be commercially available for several years, if at all.

We expect our research and development expenses to increase substantially in connection with our ongoing activities, particularly in connection with the License Agreement.

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Our primary future capital requirements will be related to our obligations under the License Agreement and funding research and development efforts.

The License Agreement, as amended, calls for initial consideration payments of $515 million (of which $500 million was paid in 2023 and $15 million was paid in 2024), as well as total contingent payments by the Company of up to $4.56 billion, as Akeso will be eligible to receive regulatory milestones of up to $1.05 billion and commercial milestones of up to $3.51 billion, many of which will be due before the Company anticipates generating any revenue from the License Agreement.

The License Agreement, as amended, calls for initial consideration payments of $515 million (of which $500 million was paid in 2023 and $15 million was paid in 2024), as well as total contingent payments by the Company of up to $4.56 billion, as Akeso will be eligible to receive regulatory milestones of up to $1.05 billion, some of which will be due before the Company anticipates generating revenue and commercial milestones of up to $3.51 billion.

We will need additional capital to fund our operations and payments under the License Agreement, which we may do via issuances of equity or debt or through global or regional partnerships in the Licensed Territory.

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Worldwide economic, social and geopolitical instability could adversely affect our operations, revenue, financial condition, results of operations or ability to raise capital.

Generally, worldwide economic conditions remain uncertain, particularly due to the effects of the conflict between Russia and Ukraine and the conflicts in the Middle East, including those in Gaza, Lebanon and Yemen, and disruptions in the banking system and financial markets, increased inflation and rising interest rates.

The general economic and capital market conditions,

both in the U.S.

Generally, worldwide economic conditions remain uncertain, particularly due to the effects of the conflict between Russia and Ukraine, the conflicts in the Middle East, including those in Gaza, Lebanon and Yemen, the escalating tensions in Venezuela and Greenland, and disruptions in the banking system and financial markets, including those in Japan, increased inflation and rising interest rates.

The general economic and capital market conditions, both in the U.S.

and worldwide, have been volatile in the past and at times have adversely affected the Company’s access to capital and increased the cost of capital.

The ongoing geopolitical conflicts in various parts of the world, including but not limited to Russia, Ukraine and Middle East, are difficult to predict and could adversely affect our business in the Licensed Territory as well as our ability to enroll patients and supply ivonescimab to various clinical sites in the world, resulting in adverse effects on our business and financial condition.

geopolitical conflicts in various parts of the world, including but not limited to Russia, Ukraine, the Middle East, Venezuela and Greenland, are difficult to predict and could adversely affect our business in the Licensed Territory as well as our ability to enroll patients and supply ivonescimab to various clinical sites in the world, resulting in adverse effects on our business and financial condition.

The capital and credit markets may not be available to support future capital raising activity on favorable terms.

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• obtaining and maintaining patent and trade secret protection and regulatory exclusivity;

• protecting our rights in our intellectual property portfolio;

• enforcing our rights in our intellectual property portfolio;

• establishing sales, marketing and distribution capabilities;

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Drug candidates in later stages of clinical trials may fail to show the desired safety and efficacy traits despite having progressed through preclinical studies and initial clinical trials.

Several factors can lead to significant variability in safety and/or efficacy results between different trials of the same drug candidate, including changes in trial procedures set forth in protocols, differences in the size, type and geographic location of the patient populations, including genetic differences, patient adherence to the dosing regimen, and other trial protocol elements

and the rate of dropout among clinical trial participants.

In the case of any trials we conduct, results may differ from earlier trials due to the larger number of clinical trial sites and additional countries involved in such later trials.

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If clinical trials of our product candidates fail to demonstrate safety and efficacy to the satisfaction of regulatory authorities, or do not otherwise produce favorable results, we may incur additional costs or experience delays, or ultimately be unable to, develop and commercialize any product candidate.

In connection with obtaining marketing approval from regulatory authorities (including the FDA, EMA, PMDA or any other regulatory authority in the Licensed Territory) for the sale of ivonescimab, or any other product candidate, we must complete preclinical development and then conduct extensive clinical trials to demonstrate the safety and efficacy of our product candidates in humans.

Prior to obtaining marketing approval from regulatory authorities (including the FDA, EMA, PMDA or any other regulatory authority in the Licensed Territory) for the sale of ivonescimab, or any other product candidate, we must complete preclinical development and then conduct extensive clinical trials to demonstrate the safety and efficacy of our product candidates in humans.

Clinical testing is expensive, difficult to design and implement, can take many years to complete and is inherently uncertain as to outcome.

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The design of a clinical trial can determine whether its results will support approval of a product, and flaws in the design of a clinical trial may not become apparent until the clinical trial is well advanced or completed.

We have limited experience in designing clinical trials and may be unable to

design and execute a clinical trial to support marketing approval.

We have limited experience in designing clinical trials and may be unable to design and execute a clinical trial to support marketing approval.

Moreover, preclinical and clinical data are often susceptible to varying interpretations and analyses, and many companies that have believed their product candidates performed satisfactorily in preclinical studies and clinical trials have nonetheless failed to obtain marketing approval of their products.

To date, we have not completed a clinical trial for ivonescimab in the Licensed Territory and cannot predict the results of such trials.

For instance, although we believe that the safety and efficacy data generated in the HARMONi study demonstrates that the ivonescimab regimen offers a potential treatment option for patients impacted by EGFR-mutant NSCLC in this setting with a favorable benefit-risk profile, FDA has noted that a statistically significant OS benefit is necessary to support marketing authorization in

this setting.

If the FDA does not agree with our analysis of the HARMONi data, they may delay or deny regulatory approval in this proposed indication, require us to resubmit the marketing application with additional data or information, or take other actions that could delay commercialization of ivonescimab and adversely impact our ability to generate revenue, our business and our operations.

We cannot predict the results of our ongoing or future clinical trials.

Regulatory authorities have substantial discretion in the approval process.

They may refuse to accept any application or may decide that our data are insufficient for approval and require additional clinical trials or other studies.

In our public communications, we may designate certain of our clinical trials as “pivotal” if we believe that these clinical trials, if successful, will support BLA submissions;

however, there can be no assurance that any clinical trial that we designate as “pivotal” will be viewed as sufficient by the FDA, the EMA and other comparable regulatory authorities in other jurisdictions to support regulatory approval.

If we are required to conduct additional clinical trials or other testing of any of our product candidates beyond those that are contemplated, we may incur significant additional costs and regulatory approval may be delayed or prevented.

There can be no guarantee that the FDA or other regulatory authorities will interpret the results or reach the same conclusions from the data as we do, or fully agree that our development plans are sufficient for submission or approval of a BLA.

In the event that the FDA requires us to conduct clinical trials with more patients than planned, to conduct clinical trials with designs or endpoints other than we currently anticipate, we may not have the funding to enlarge or conduct such trials and we may not be able to raise sufficient funding to do so, which could delay or prevent commercialization of our product candidates.

In addition, the FDA or other regulatory authorities may change their views on aspects of the clinical programs, including clinical trial designs, or the ability of the trials as designed to support approval of a product.

If we are unable to effectively and efficiently resolve and comply with the inquiries and requests of the FDA and other comparable international regulatory authorities, the approval of our product candidates may be delayed, which could delay or prevent commercialization of our product candidates.

Regulatory requirements and timelines may affect the scope and timeline of our trials and the potential market for our product candidates.

As we expand into additional countries and sites for our current and additional clinical trials, we are required to obtain the regulatory approval of the applicable clinical trial applications with the respective regulatory authorities and approvals from central or local institutional review boards.

We may decide to modify our plans to enter certain regions or countries based on the timelines and requirements from the respective regulatory regions.

We may decide to modify our plans to enter certain regions or countries based on the timelines and requirements for the respective regulatory regions.

If the process to obtain regulatory approvals in a given region or country places onerous requirements on the Company or if the Company cannot reasonably obtain such approvals without material delays to its plans, we may choose not to enter certain regions or countries for our clinical trials, which may delay the development of our product in those countries and impact the scope of our dataset and market for our products.

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• regulators, institutional review boards or independent ethics committees may require that we or our investigators suspend or terminate clinical research for various reasons, including noncompliance with regulatory requirements or a finding that the participants are being exposed to unacceptable health risks;

drug manufactured for such trials was not utilized prior to its expiration and needed to be replaced, or if there were disruptions in our supply chain due to weather conditions, natural disasters or contagious diseases or illnesses, or pandemics or epidemics;

• the supply or quality of our product candidates, comparator drugs or other materials necessary to conduct clinical trials of our product candidates in adolescent patients may be insufficient or inadequate, which may occur if, for example, enrollment for our clinical trial programs are delayed and the clinical supply of ivonescimab or related comparator drug manufactured for such trials was not utilized prior to its expiration and needed to be replaced, or if there were disruptions in our supply chain due to weather conditions, natural disasters or contagious diseases or illnesses, or pandemics or epidemics;

• our product candidates may have undesirable side effects or other unexpected characteristics, causing us or our investigators, regulators, institutional review boards or independent ethics committees to suspend or terminate the clinical trials;

• preclinical tests or clinical trials not beginning as planned, needing to be restructured or not being completed on schedule, or at all;

• data privacy or other laws being implemented that restrict transfer of patient data from one country to another.

If serious adverse or inappropriate side effects are identified during the development of any product candidate, we may need to abandon or limit our development of that product candidate.

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Any of these occurrences could materially harm our business.

We have conducted, and may in the future conduct, clinical trials for current or future product candidates outside the United States, and the FDA and comparable foreign regulatory authorities may not accept data from such trials.

We are currently conducting clinical trials in China, and we expect to continue to conduct trials internationally in the future.

The acceptance of data from clinical trials conducted outside the United States by the FDA or other regulatory authorities may be subject to certain conditions or may not be accepted at all.

In cases where data from foreign clinical trials are intended to serve as the sole basis for regulatory approval in the United States, the FDA will generally not approve the application unless (i) the data are applicable to the U.S.

population and U.S.

medical practice and (ii) the trials were performed by clinical investigators of recognized competence and pursuant to GCP regulations, and the data may be 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.

In addition, even where the foreign study data are not intended to serve as the sole basis for approval, the FDA will not accept the data as support for an application for marketing approval unless the study is well-designed and well-conducted in accordance with GCPs and the FDA is able to validate the data from the study through an

onsite inspection if deemed necessary.

Additionally, the FDA’s clinical trial requirements, including sufficient size of patient populations and statistical powering, must be met.

Many foreign regulatory authorities have similar approval requirements.

In addition, such foreign trials are subject to the applicable local laws of the foreign jurisdictions where the trials are conducted.

Conducting clinical trials outside the United States also exposes us to additional risks, including risks associated with foreign exchange fluctuations, compliance with foreign manufacturing, customs, shipment and storage requirements, and cultural differences in medical practice and clinical research, and diminished protection of intellectual property in some countries.

There can be no assurance that the FDA or any comparable foreign regulatory authority will accept data from trials conducted outside of the United States or the applicable jurisdiction.

For example, for FDA acceptance, we will have to demonstrate that the foreign data are applicable to the U.S.

population and U.S.

medical practice.

If the FDA or other regulatory authorities do not accept such data, it would result in the need for additional trials, which could be costly and time-consuming, and which may result in current or future product candidates that we may develop being delayed or not receiving approval for commercialization in the applicable jurisdiction.

Even if a product candidate receives marketing approval, it may fail to achieve the degree of market acceptance by physicians, patients, third-party payors and others in the medical community necessary for commercial success.

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If we are unable to establish sales and marketing capabilities or enter into agreements with third parties to market and sell our product candidates, we may not be successful in commercializing a product candidate if and when such product candidates are approved.

We do not have a sales or marketing infrastructure and have no experience as a company in the sale or marketing of pharmaceutical products, although certain employees do have experience in the sale and marketing of pharmaceutical products.

To achieve commercial success for any approved product, we must either develop a sales and marketing organization or outsource these functions to third parties.

With our BLA submission in Q4, 2025 and the FDA’s acceptance for filing the BLA in January 2026, we are in the process of building our Sales, Marketing and Market Access organization.

We have already hired our senior commercial leadership team with extensive experience in the sale and marketing of pharmaceutical products.

In addition, we are in the process to build infrastructure of supporting operations to ensure a successful commercial launch.

To achieve commercial success for any approved product, we must either develop a sales and marketing organization and/or outsource these functions to third parties .

If ivonescimab receives marketing approval, we may seek commercialization partners in some parts of the Licensed Territory.

There are risks involved with establishing our own sales and marketing capabilities and entering into arrangements with third parties to perform these services.

For example, recruiting and training a sales force is expensive and time-consuming and could delay any product launch.

If the commercial launch of a product candidate for which we recruit a sales force and establish marketing capabilities is delayed or does not occur for any reason, we would have prematurely or unnecessarily incurred these commercialization expenses.

There are risks involved with establishing our own sales and marketing capabilities as well as entering into arrangements with third parties to perform these services.

If the commercial launch of a product candidate for which we recruit a sales force and establish marketing capabilities is delayed or does not occur for any reason, we would have incurred these commercialization expenses.

This may be costly, and our investment would be lost if we cannot retain or reposition our sales and marketing personnel.

Factors that may inhibit our efforts to commercialize our products on our own include:

• our inability to recruit, train and retain adequate numbers of effective sales and marketing personnel;

• our inability to recruit, train and retain adequate numbers of effective sales and marketing personnel in a timely fashion;

• Inability to build a marketing operations infrastructure with the development of advance analytics allowing for different channels to be utilized for promotions beyond the sales organization

• the inability of sales personnel to obtain access to or persuade adequate numbers of physicians to prescribe any future products;

• Lack of appropriate guidelines, pathways, and formulary placement for reimbursement;

• Lack of key opinion development for the support of the product data;

• the lack of complementary products to be offered by sales personnel, which may put us at a competitive disadvantage relative to companies with more extensive product lines;

• unforeseen costs and expenses associated with creating an independent sales and marketing organization.

Evolving competition with new products or existing products with new data or combinations which may confer efficacy or safety advantages.

If we enter into arrangements with third parties to perform sales and marketing services, our product revenues or the profitability of these product revenues to us are likely to be lower than if we were to market and sell any products that we develop ourselves.

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The development and commercialization of new drug products is highly competitive.

We face competition with respect to our current product candidates and any products we may seek to develop or commercialize whether ourselves or through third-party partners, in the future from major pharmaceutical companies, specialty pharmaceutical companies and biotechnology companies worldwide.

We face competition with respect to our current product candidate and any products we may seek to develop or commercialize whether ourselves or through third-party partners, in the future from major pharmaceutical companies, specialty pharmaceutical companies and biotechnology companies worldwide.

Several pharmaceutical and biotechnology companies have established themselves in the market for the treatment of NSCLC, and several additional companies are developing products for the treatment of NSCLC.

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The proposed indications for ivonescimab in the HARMONi-3 and HARMONi-7 clinical trial settings in first-line NSCLC may face competition from clinical candidates such as novel immunotherapy targets including various clinical candidates targeting T-cell immunoreceptors with Ig and ITIM domains (TIGIT) and lymphocyte activation gene 3 (LAG-3) each of which have various developers for different candidates as either monoclonal antibodies or multispecific antibodies, a bispecific antibody, volrustomig (AstraZeneca), and antibody drug conjugates (ADCs) with novel targets such as datopotamab deruxetecan (AstraZeneca and Daiichi Sankyo), sacituzumab tirumotecan (Merck), and sigvotatug vedotin (Pfizer), each having announced, are currently enrolling in, or having completed enrollment in Phase III clinical trials.

For those patients EGFR mutations, there are several targeted therapies that have also been approved in the front-line setting, including, but not limited to, osimertinib (AstraZeneca) with or without chemotherapy and amivantamab and lazertinib (both from Johnson & Johnson).

The proposed indication for ivonescimab in the HARMONi clinical trial setting, post third-generation EGFR-TKIs such as osimertinib or lazertinib, may face competition from amivantamab plus chemotherapy, as well as clinical candidates such as as datopotamab deruxetecan (AstraZeneca and Daiichi Sankyo) and patritumab deruxtecan (Merck and Daiichi Sankyo).

For those patients having EGFR mutations, there are several targeted therapies that have also been approved in the front-line setting, including, but not limited to, osimertinib (AstraZeneca) with or without chemotherapy and amivantamab and lazertinib (both from Johnson & Johnson).

The proposed indication for ivonescimab in the HARMONi clinical trial setting, post third-generation EGFR-TKIs such as osimertinib or lazertinib, may face competition from amivantamab plus chemotherapy, as well as clinical candidates such as datopotamab deruxetecan (AstraZeneca and Daiichi Sankyo) and patritumab deruxtecan (Merck and Daiichi Sankyo).

There are several PD-(L)1/VEGF(R2) bispecific antibodies in development or with planned development globally.

These include, but are not limited to BNT327, which is owned by BioNTech SE, which has begun conducting Phase III clinical studies globally, and LM-299, which was licensed globally by Merck & Co., Inc.

in November 2024.

These include, but are not limited to pumitamig (BNT327), which is owned by BioNTech SE and being developed in a collaboration with Bristol Myers Squibb Co.

since June 2025, which has begun conducting Phase III clinical studies globally, PF-08634404 (PF’4404 / SSGJ-707), which was licensed globally, ex-China by Pfizer Inc.

in July 2025, LM-299, which was licensed globally by Merck & Co., Inc.

in November 2024, and RC148, which was licensed outside of Greater China by AbbVie Inc.

in January 2026.

Potential competitors also include academic institutions, government agencies and other public and private research organizations that conduct research, seek patent protection and establish collaborative arrangements for research, development, manufacturing and commercialization.

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We believe that many competitors are attempting to develop therapeutics for the target indications of our product candidates, including academic institutions, government agencies, public and private research organizations, large pharmaceutical companies and smaller more focused companies.

Multiple in-class and related competitors for our product candidates are and can be developed, our competitive position could be compromised because it may be more difficult for us to obtain marketing approval for that product candidate and market acceptance of that product candidate due to a similar competitor.

Multiple in-class and related competitors for our product candidate are and can be developed, our competitive position could be compromised because it may be more difficult for us to obtain marketing approval for that product candidate and market acceptance of that product candidate due to a similar competitor.

In addition, any product that competes with another approved product typically must demonstrate compelling advantages in efficacy, convenience, tolerability or safety, or some combination of these factors, to gain regulatory approvals, overcome price competition and be commercially successful.

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Mergers and acquisitions in the pharmaceutical and biotechnology industries may result in even more resources being concentrated among a smaller number of our competitors.

Smaller and other early-stage companies may also prove to be significant competitors, particularly through collaborative arrangements with large and

established companies.

Smaller and other early-stage companies may also prove to be significant competitors, particularly through collaborative arrangements with large and established companies.

These third parties compete with us in recruiting and retaining qualified scientific and management personnel, establishing clinical trial sites and patient registration for clinical trials, as well as in acquiring technologies complementary to or necessary for our programs.

If we fail to plan, execute and manage our growth effectively, our ability to develop and commercialize products could suffer.

We expect that if our clinical product candidates continue to progress in development, and we continue to build our clinical operations and invest in our commercial operations, we will require significant additional investment in personnel, infrastructure and resources, Our ability to achieve our research, development and commercialization objectives depends on our ability to respond timely and effectively to these demands and expand our internal organization, systems and controls to accommodate additional anticipated growth.

Our ability to achieve our research, development and commercialization objectives depends on our ability to respond timely and effectively to these demands and expand our internal organization, systems and controls to accommodate additional anticipated growth.

The expansion of our operations may lead to significant costs and may divert our management and business resources.

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Our primary product candidate, ivonescimab, is subject to the License Agreement from Akeso, which is revocable in certain circumstances, including in the event we do not achieve certain payment deadlines.

Without the patents under the License Agreement, we will not be able to continue to develop ivonescimab.

Without the rights to the patents under the License Agreement, we will not be able to continue to develop ivonescimab.

The License Agreement may be terminated by Akeso in the event of a material breach by Summit or if we default in the performance of any of our material obligations under the License Agreement, and such default continues for 90 days, or with respect to any breach of any undisputed payment obligations, for 60 days, or with respect to any breach of a supply requirement, for 30 days after written notice thereof.

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• ownership of specific intellectual property;

• the impact on payments and costs associated with commercialization if there is blocking intellectual property in or costs associated with prosecution, maintenance and enforcement under the Akeso License Agreement.

• the impact on payments and costs associated with commercialization if there is blocking intellectual property or the costs associated with prosecution, maintenance and enforcement of intellectual property under the License Agreement.

These issues, if they arise, could narrow what we believe to be the scope of our rights to the relevant intellectual property or technology, increase what we believe to be our financial or other obligations under the relevant agreement, or increase our costs to develop, manufacture and commercialize products under the License Agreement.

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Our ability to generate revenues from these arrangements will depend on our collaborators’ abilities and efforts to successfully perform the functions assigned to them in these arrangements.

Our current collaborations pose, and any future collaboration likely will pose, numerous risks to us, including the following:

Our current collaborations pose, and any future collaborations likely will pose, numerous risks to us, including without limitation the following:

• collaborators have significant discretion in determining the efforts and resources that they will apply to these collaborations and may not perform their obligations as expected;

• collaborators may de-emphasize or not pursue development and commercialization of our product candidates or may elect not to continue or renew development or commercialization programs based on clinical trial results, changes in the collaborators’ strategic focus, including as a result of a sale or disposition of a business unit or development function, or available funding, or external factors such as an acquisition that diverts resources or creates competing priorities;

• collaborators may delay clinical trials, provide insufficient funding for a clinical trial program, stop a clinical trial or abandon a product candidate, repeat or conduct new clinical trials or require a new formulation of a product candidate for clinical testing;

• a collaborator with marketing and distribution rights to multiple products may not commit sufficient resources to the marketing and distribution of our product relative to other products;

• collaborators may delay clinical trials, provide insufficient funding for a clinical trial program, stop a clinical trial or abandon a product candidate, repeat or conduct new or unsuccessful clinical trials or require a new formulation of a product candidate for clinical testing;

• collaborators could independently develop, or develop with third parties, products that compete directly or indirectly with our products or product candidates if the collaborators believe that competitive products are more likely to be successfully developed or can be commercialized under terms that are more economically attractive than ours;a collaborator with marketing and distribution rights to multiple products may not commit sufficient resources to the marketing and distribution of our product relative to other products;

• collaborators may not properly maintain or defend our intellectual property rights or may use our proprietary information in such a way as to invite litigation that could jeopardize or invalidate our intellectual property or proprietary information or expose us to potential litigation;

• collaborators may infringe the intellectual property rights of third parties, which may expose us to litigation and potential liability;

• disputes may arise between the collaborator and us as to the ownership of intellectual property arising during the collaboration;

• disputes may arise between the collaborator and Summit as to the ownership of intellectual property arising during the collaboration;

• we may grant exclusive rights to our collaborators, which would prevent us from collaborating with others;

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We have limited personnel with experience in drug manufacturing and lack the resources and the capabilities to manufacture any of our product candidates on a clinical or commercial scale.

We currently rely on third parties for supply of the active pharmaceutical ingredients ("API"), drug substance or drug product, in our product candidates.

We currently rely on third parties for supply of the active pharmaceutical ingredients ("API"), drug substance and drug product in our product candidates.

Our strategy is to outsource all manufacturing of our product candidates and products to third parties.

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The third-party manufacturers may not successfully carry out their contractual duties or obligations, the occurrence of which could substantially increase our costs and limit our supply of such product candidates.

The demand for third-party manufacturer’s services is very high, and such manufacturers could be subject to market transactions including mergers, acquisitions and other market consolidation transactions that limit their ability to provide products and services to us thereby increasing the time and cost it could take us to manufacture our product.

The demand for third-party manufacturers’ services is very high, and such manufacturers could be subject to market transactions including mergers, acquisitions and other market consolidation transactions that limit their ability to provide products and services to us thereby increasing the time and cost it could take us to manufacture our product.

Even if we are able to establish and maintain arrangements with third-party manufacturers, reliance on third-party manufacturers, including Akeso, entails additional risks, including:

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• the possible termination or non-renewal of the agreement by the third party at a time that is costly or inconvenient for us.

Third-party manufacturers, including Akeso, may not be able to comply with current good manufacturing practice (“cGMP”), regulations or similar regulatory requirements outside the United States.

Our failure, or the failure of our third-party manufacturers, including Akeso, to comply with applicable regulations could result in sanctions being imposed on us, including fines, injunctions, civil penalties, delays, suspension or withdrawal of approvals, license revocation, seizures or recalls of product candidates or products, operating restrictions and criminal prosecutions, any of which could significantly and adversely affect supplies of our product candidates.

The manufacturing process for a product candidate is subject to FDA and other foreign regulatory authority review.

We, and our suppliers and manufacturers, must meet applicable manufacturing requirements and undergo rigorous facility and process validation tests required by regulatory authorities in order to comply with regulatory requirements, such as cGMP.

Securing regulatory approval also requires the submission of information about the product manufacturing process to, and inspection of manufacturing facilities by, the FDA and other foreign regulatory authorities.

If our contract manufacturers are unable to maintain a compliance status acceptable to the FDA and other foreign regulatory authorities, our product candidates may not be approved.

If our contract manufacturers cannot successfully manufacture material that conforms to our specifications and the strict regulatory requirements of the FDA or comparable foreign regulatory authorities, we may not be able to rely on their manufacturing facilities for the manufacture of components of any product candidates.

Moreover, although we do not control the manufacturing process at our contract manufacturers and are completely dependent on them for compliance with current regulatory requirements, we are nonetheless responsible for ensuring that any product candidates are manufactured in accordance with applicable laws and regulatory requirements.

In the event that any of our manufacturers fails to comply with such requirements or to perform its obligations in relation to quality, timing or otherwise, or if our supply of components or other materials becomes limited or interrupted for other reasons, we may be forced to enter into an agreement with another third party, which we may not be able to do on reasonable terms, if at all.

Third-party manufacturers, including Akeso, may not be able to comply with cGMP, regulations or similar regulatory requirements outside the United States.

suspension or withdrawal of approvals, license revocation, seizures or recalls of product candidates or products, operating restrictions and criminal prosecutions, any of which could significantly and adversely affect supplies of our product candidates.

Our product candidates and any products that we may develop may compete with other product candidates and products for access to manufacturing facilities.

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Moreover, if our third-party manufacturers, including Akeso, are unable to successfully scale up the manufacture of our product candidates in sufficient quality and quantity, the development, testing and clinical trials of that product candidate may be delayed or infeasible, and regulatory approval or commercial launch of that product candidate may be delayed or not obtained, which could significantly harm our business.

If the third parties, including Akeso, that we engage to manufacture product for our preclinical tests and clinical trials should cease to continue to do so for any reason, including due to the novel coronavirus or another outbreak, we likely would experience delays in advancing these clinical trials while we identify and qualify replacement suppliers, and we may be unable to obtain replacement supplies on terms that are favorable to us.

If the third parties, including Akeso, that we engage to manufacture product for our preclinical tests and clinical trials should cease to continue to do so for any reason, including due to the coronavirus or another outbreak, we likely would experience delays in advancing these clinical trials while we identify and qualify replacement suppliers, and we may be unable to obtain replacement supplies on terms that are favorable to us.

In addition, if we are not able to obtain adequate supplies of our product candidates or the drug substances used to manufacture them, it will be more difficult for us to develop our product candidates and compete effectively.

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For example, we remain responsible for ensuring that each of our clinical trials is conducted in accordance with the general investigational plan and protocols for the clinical trial.

Moreover, the FDA requires us to comply with standards, commonly referred to as GCP, for conducting, recording and reporting the results of clinical trials to assure that data and reported results are credible and accurate and that the rights, integrity of data and confidentiality of clinical trial participants are protected.

Moreover, the FDA requires us to comply with standards, commonly referred to as GCP, for conducting, recording and reporting the results of clinical trials to ensure that data and reported results are credible and accurate and that the rights, integrity of data and confidentiality of clinical trial participants are protected.

The EMA and PDMA impose similar requirements on us for products that are the subject of clinical trials in the E.U., including the U.K., and Japan.

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Our ability to commercialize ivonescimab or any other product candidate successfully also will depend in part on the extent to which coverage and adequate reimbursement for these products and related treatments will be available from government health administration authorities, private health insurers and other organizations.

Significant uncertainty exists as to the coverage and reimbursement status of any of our products for which we obtain regulatory approval.

Government authorities and other third-party payors, such as private health insurers and health maintenance organizations, decide which medications they will pay for and establish reimbursement levels.

A primary trend in the U.S.

healthcare industries and elsewhere is cost containment.

Government authorities and other third-party payors have attempted to control costs by limiting coverage and the amount of reimbursement for particular medications.

Increasingly, third-party payors are requiring that drug companies provide them with predetermined discounts from list prices and are challenging the prices charged for medical products.

In the United States, although private third-party payors tend to follow Medicare practices, no uniform or consistent policy of coverage and reimbursement for drug products exists among third-party payors.

Therefore, coverage and reimbursement for drug products can differ significantly from payor to payor as well as from state to state.

Consequently, the coverage determination process is often a time-consuming and costly process that must be played out across many jurisdictions and different entities and that will require us to provide scientific, clinical and health economics support for

the use of our products compared to current alternatives and do so to each payor separately, with no assurance that coverage and adequate reimbursement will be obtained and in what time frame.

We cannot be sure that coverage and reimbursement will be available for ivonescimab or any other product that we commercialize and, if coverage and reimbursement are available, the level of reimbursement.

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There may be significant delays in obtaining coverage and reimbursement for newly approved drugs, and coverage may be more limited than the purposes for which the drug is approved by the applicable regulatory authority.

Moreover, eligibility for coverage and reimbursement does not imply that any drug will be paid for in all cases or at a rate that covers our costs,

including, but not limited to, research, development, intellectual property, manufacture, sale and distribution expenses.

Moreover, eligibility for coverage and reimbursement does not imply that any drug will be paid for in all cases or at a rate that covers our costs, including, but not limited to, research, development, intellectual property, manufacture, sale and distribution expenses.

Interim reimbursement levels for new drugs, if applicable, may also not be sufficient to cover our costs and may not be made permanent.

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Net prices for drugs may be reduced by mandatory discounts or rebates required by government healthcare programs or private payors and by any future relaxation of laws that presently restrict imports of drugs from countries where they may be sold at lower prices than in the United States.

In the United States, third-party payors often rely upon Medicare coverage policy and payment limitations in setting their own reimbursement policies.

In the E.U., reference pricing systems and other measures may lead to cost containment and reduced prices.

Our inability to promptly obtain coverage and adequate reimbursement rates from both government-funded and private payors for any approved products that we develop could have a material adverse effect on our operating results, our ability to raise capital needed to commercialize products and our overall financial condition.

Our inability to promptly obtain and maintain coverage and adequate reimbursement rates from both government-funded and private payors for any approved products that we develop could have a material adverse effect on our operating results, our ability to raise capital needed to commercialize products and our overall financial condition.

In addition, third-party payors, whether domestic or foreign, governmental or commercial, are developing increasingly sophisticated methods of controlling healthcare costs.

In both the United States and certain foreign jurisdictions, there have been a number of legislative and regulatory changes to healthcare systems that could impact our ability to sell our product candidates, if approved, profitably.

There have been, and likely will continue to be, legislative and regulatory proposals at the federal and state levels directed at broadening the availability of, and containing or lowering the cost of, healthcare.

The implementation of cost containment measures that third-party payors and healthcare providers are instituting and any other healthcare reforms may prevent us from being able to generate, or may reduce, our revenues from the sale of our product candidates, if approved, and our product candidates may not be profitable.

Such reforms could have an adverse effect on anticipated revenue from product candidates for which we may obtain regulatory approval and may affect our overall financial condition and ability to develop product candidates.

Governments outside the United States tend to impose strict price controls, which may adversely affect our revenues, if any.

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• unexpected or unfavorable changes in regulatory requirements;

• changes in U.S.

law regarding data security and providing sensitive personal data to China;

• difficulties in managing foreign relationships and operations generally.

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Due to our collaboration with Akeso, we are reliant on collaborating with a company with significant operations in China.

We do not know whether and to what extent the Trump administration will implement or alter any tariffs, laws or regulations that may increase the cost or feasibility of importing and exporting products, components and information from China to the United States and vice versa.

Further, the effect of any such new tariffs or actions on our industry and customers is unknown and difficult to predict.

As additional tariffs, legislation and regulations are implemented, or if existing trade agreements are renegotiated, or if China or other affected countries take retaliatory trade actions, such changes could have a material adverse effect on our clinical development plans, business, financial condition, results of operations or cash flows.

We do not know whether and to what extent the Trump administration will in the future implement or alter any tariffs, laws or regulations that may increase the cost or feasibility of importing and exporting products, components and information from China to the United States and vice versa.

Further, the effect of any such new tariffs or actions on our industry or customers, and whether they may be subject to any exceptions, is unknown and difficult to predict.

As additional tariffs, legislation or regulations are implemented, or if existing trade agreements are renegotiated, or if China or other affected countries take retaliatory trade actions, such changes could have a material adverse effect on our clinical development plans, business, financial condition, results of operations or cash flows.

In addition, certain Chinese biotechnology companies may become subject to trade restrictions, sanctions, other regulatory requirements, or proposed legislation by the U.S.

government, which could restrict or even prohibit our ability to work with such entities, thereby potentially disrupting the supply of material to us.

For example, the BIOSECURE Act, which was recently signed into law in December 2025, prohibits U.S.

federal agencies from entering into or renewing any contract with any entity that uses biotechnology equipment or services produced or provided by a “biotechnology company of concern” to perform that contract as well as authorizes the U.S.

government to name additional Chinese “biotechnology companies of concern.” While prior versions of the BIOSECURE Act explicitly named “biotechnology companies of concern,” the revised version defines a “biotechnology company of concern” as an entity that is identified on the annual 1260H List of Chinese military companies (the “1260H List”) issued by the U.S.

Department of Defense, any entity designated by the U.S.

Government as such, and certain affiliates of the foregoing.

If this law, or similar laws that may be enacted, impact Chinese biotechnology manufacturing companies that are or may become contractors or subcontractors of ours or provide biotechnology equipment or services in the manufacture of our products or products candidates, we may be restricted in our ability to work with such Chinese biotechnology manufacturing companies to the extent we would contract with, or otherwise receive funding from, the U.S.

government, or work with sites or institutions that may receive funding from the U.S.

As a result, we may need to seek alternative contract manufacturer relationships.

While we believe we will be able to identify and contract with such alternative contract manufacturers, we cannot predict the terms of any such alternative arrangement nor what actions may ultimately be taken with respect to trade relations between the United States and China or other countries, what products and services may be subject to such actions or what actions may be taken by China or the other countries in retaliation.

Product liability lawsuits against us could cause us to incur substantial liabilities and to limit commercialization of any products that we may develop.

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tax laws or the interpretation thereof or the imposition of new or increased taxes or fees could increase our future tax liabilities and adversely affect our operating results and cash flows.

From time to time, U.S.

federal, state and non-U.S.

legislation has been proposed that would, if enacted into law, make significant changes to tax laws, including certain key U.S.

federal, state and non-U.S.

income tax provisions currently applicable to companies like us.

It is unclear whether these or similar changes will be enacted and, if enacted, how soon any such changes could take effect.

The passage of any legislation as a result of these proposals and other changes in tax laws or the imposition of new or increased taxes or fees could affect our effective tax rates in countries where we have operations and could have an adverse effect on our overall tax position in the future, along with increasing the complexity, burden and cost of tax compliance, in each case potentially increasing our future tax liabilities and adversely affect our operating results and cash flows.

United States

Recent changes in tax law may adversely affect our business or financial condition.

On December 22, 2017, the U.S.

government enacted the Tax Cuts and Jobs Act (the “TCJA”), which significantly reformed the Code.

The TCJA, among other things, contained significant changes to corporate taxation, including certain limitations on interest deductions, limitations of the deduction for certain net operating losses, and the modification or repeal of many business deductions and credits.

Beginning with costs incurred in 2022, the TCJA also eliminated the option to deduct research and development expenditures and requires taxpayers to capitalize and amortize them over five or fifteen years.

If this requirement is not modified, it may impact our effective tax rate and our cash tax liability in future years.

More recently, the IRA contained, among other things, a corporate alternative minimum tax, which imposes a 15% minimum tax will be imposed on certain financial statement income of “applicable corporations” in taxable years beginning after December 31, 2022.

The IRA also imposes a 1% non-deductible excise tax on the fair market value of any stock repurchased by a publicly traded domestic corporation during any taxable year, with the fair market value of such repurchased stock reduced by the fair market value of certain stock issued by such corporation during such taxable year.

Department of the Treasury and the IRS have released proposed and final regulations and other interpretive guidance

relating to the TCJA and the IRA.

Any significant variance from our current interpretation of such regulations and interpretive

guidance could result in a change in our analysis of the application of the TCJA and the IRA to us and its impact on our

operations and cash flows.

Recent announcements of changes in the U.K.

research and development (“R&D”) regime are likely to impact the level of cash benefit that the Company will be able to receive in respect of the R&D activity.

As a result of a reduction in rates applied in the Small and Medium Enterprise (“SME”) regime, the cash credit that the Company will be able to obtain is likely to reduce if the qualified spending remains consistent.

This will be partly offset by an increase in the Research and Development Expenditure Credit (“RDEC”) regime.

In addition, there is a refocus of relief towards U.K.

activity and therefore costs outside the U.K.

are expected to be restricted going forward with further changes anticipated following a government consultation being launched with the intention of merging the SME and RDEC schemes.

Our future tax liabilities may be greater than expected if our net operating loss carryforwards and other tax attributes are limited, we do not generate expected deductions, or tax authorities challenge our tax positions.

As of December 31, 2024, we have U.S.

federal and state net operating loss (“NOL”) carryforwards of approximately $44.3 million and $7.0 million, respectively, U.S.

federal research and development tax credit carryforwards of approximately $7.0 million, and U.K.

NOL carryforwards of approximately $198.7 million.

Our ability to utilize these tax attributes to offset potential future taxable income and related income taxes that would otherwise be due is dependent upon our generation of future taxable income, which cannot be assured.

Changes to tax laws in the US, UK, and other countries, as well as new or increased taxes or fees, could raise our future tax liabilities and negatively impact our operating results and cash flows.

Recent US tax reforms, such as the IRA and the One Big Beautiful Bill Act (“OBBBA”), have introduced significant changes to corporate taxation, including new rules for interest deductions, research and development expenses, and stock repurchases.

The OBBBA, signed into law on July 4, 2025, has multiple effective dates, with certain provisions effective in 2025 and others implemented through 2027.

In the UK, updates to the research and development tax regime may reduce the cash benefits we receive, especially for spending outside the UK, and further changes are expected as the government considers merging existing research and development schemes.

The interpretation and implementation of these laws may change, and any new legislation or guidance could affect our tax rates, increase compliance costs, and have an adverse effect on our financial position.

Our future tax liabilities may be greater than expected if our net operating loss carryforwards and other tax attributes are limited or tax authorities challenge our tax positions.

Our ability to utilize net operating loss (NOL) carryovers and other tax attributes to offset potential future taxable income and related income taxes that would otherwise be due is dependent upon our generation of future taxable income, which cannot be ensured.

In addition, our ability to use NOL carryforwards and other tax attributes may be subject to significant limitations under Sections 382 and 383 of the Code.

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An ownership change generally occurs if one or more stockholders (or groups of stockholders) who are each deemed to own at least 5% of such corporation’s stock change their ownership by more than 50 percentage points over their lowest ownership percentage within a rolling three-year period.

In the event that we were to undergo an ownership change, utilization of our NOL carryforwards and other tax attributes would be subject to an annual limitation under Section 382 of the Code and Section 383 of the Code (as applicable), determined by

multiplying the value of our stock at the time of the ownership change by the applicable long-term tax-exempt rate in effect during the month in which the ownership change occurs, subject to certain adjustments, which could result in a portion of our tax attributes expiring prior to their utilization.

In the event that we were to

undergo an ownership change, utilization of our NOL carryforwards and other tax attributes would be subject to an annual limitation under Section 382 of the Code and Section 383 of the Code (as applicable), determined by multiplying the value of our stock at the time of the ownership change by the applicable long-term tax-exempt rate in effect during the month in which the ownership change occurs, subject to certain adjustments, which could result in a portion of our tax attributes expiring prior to their utilization.

Any unused annual limitation may be carried over to later years.

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tax authorities could increase our future tax liabilities and adversely affect our operating results and cash flows.

In the event that our NOL carryforwards or other tax attributes are subject to future limitation (including due to an ownership change under Sections 382 and 383 of the Code), deductions are not generated as expected, or if one or more of our tax positions are successfully challenged by the IRS or other tax authorities (in a tax audit or otherwise), our future tax liabilities may be greater than expected, which could adversely affect our operating results and cash flows.

Laws and regulations affecting government contracts make it more costly and difficult for us to successfully conduct our business.

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Regulatory authorities have substantial discretion in the approval process and may refuse to accept any application or may decide that our data are insufficient for approval and require additional preclinical, clinical or other studies.

In addition, varying interpretations of the data obtained from preclinical and clinical testing could delay, limit or

prevent marketing approval of a product candidate.

In addition, varying interpretations of the data obtained from preclinical and clinical testing could delay, limit or prevent marketing approval of a product candidate.

Any marketing approval we ultimately obtain may be limited or subject to restrictions or post-approval commitments that render the approved product not commercially viable.

If we experience delays in obtaining approval or if we fail to obtain approval of our product candidates, the commercial prospects for our product candidates may be harmed and our ability to generate revenues will be materially impaired.

If we experience delays in

obtaining approval or if we fail to obtain approval of our product candidates, the commercial prospects for our product candidates may be harmed and our ability to generate revenues will be materially impaired.

We also are required to register ongoing clinical trials and post the results of completed clinical trials on a U.S.

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Failure to comply would violate federal requirements and could result in fines and/or civil and criminal sanctions, which would delay the regulatory approval process and result in adverse publicity.

Our failure to obtain marketing approval in a jurisdiction would prevent our product candidates from being marketed in such jurisdiction, and any approval we are granted for our product candidates in one jurisdiction would not assure approval of our product candidates in any other jurisdictions.

Our failure to obtain marketing approval in a jurisdiction would prevent our product candidates from being marketed in such jurisdiction, and any approval we are granted for our product candidates in one jurisdiction would not ensure approval of our product candidates in any other jurisdictions.

In order to market and sell ivonescimab and our other product candidates in foreign jurisdictions, we must obtain separate marketing approvals and comply with numerous and varying regulatory requirements in those jurisdictions.

The approval procedure varies among countries and can involve additional testing.

The time required to obtain approval may differ from that required to obtain FDA or EMA approval.

The regulatory approval process outside the United States and Europe generally includes all of the risks associated with obtaining FDA and EMA approval.

The time required to obtain approval may differ from that required to obtain FDA or EMA/EC approval.

The regulatory approval process outside the United States and Europe generally includes all of the risks associated with obtaining FDA and EMA/EC approval.

In addition, some countries outside the United States and Europe require approval of the sales price of a drug before it can be marketed.

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We may not obtain marketing, pricing or reimbursement approvals outside the United States and Europe on a timely basis, if at all.

Approval by the FDA or the EMA does not ensure approval by regulatory authorities in other countries or jurisdictions, and approval by one regulatory authority outside the United States and Europe does not ensure approval by regulatory authorities in other countries or jurisdictions or by the FDA or the EMA.

Approval by the FDA or the EMA/EC does not ensure approval by regulatory authorities in other countries or jurisdictions, and approval by one regulatory authority outside the United States and Europe does not ensure approval by regulatory authorities in other countries or jurisdictions or by the FDA or the EMA/EC.

We may not be able to file for marketing approvals and may not receive necessary approvals to commercialize our products in any market.

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Even if we obtain marketing approvals for our product candidates, the terms of approvals and ongoing regulation of our products may limit how we manufacture and market our products and compliance with such requirements may involve substantial resources, which could materially impair our ability to generate revenue.

Even if marketing approval of a product candidate is granted, an approved product and its manufacturer and marketer are subject to ongoing review and extensive regulation, including the requirement to implement a risk evaluation and mitigation strategy or to conduct costly post-marketing studies or clinical trials and surveillance to monitor the safety or efficacy of the product.

Even if marketing approval of a product candidate is granted, an approved product and its manufacturer and marketer are subject to ongoing review and extensive regulation, including the potential requirement to implement a risk evaluation and mitigation strategy or to conduct costly post-marketing studies or clinical trials and surveillance to monitor the safety or efficacy of the product.

We and our collaborators must also comply with requirements concerning advertising and promotion for any of our product candidates for which we obtain marketing approval.

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Thus, neither we nor our collaborators will be able to promote any products we develop for indications or uses for which they are not approved.

In addition, manufacturers of approved products and those manufacturers’ facilities are required to ensure that quality control and manufacturing procedures conform to cGMP, which include requirements relating to quality control and quality assurance as well as the corresponding maintenance of records and documentation and reporting

requirements.

We and our contract manufacturers could be subject to periodic unannounced inspections by the FDA to monitor and ensure compliance with cGMP.

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The FDA and other federal and state agencies, including the DOJ, closely regulate compliance with all requirements governing prescription drug products, including requirements pertaining to marketing and promotion of drugs in accordance with the provisions of the approved labeling and manufacturing of products in accordance with cGMP requirements.

The FDA and DOJ impose stringent restrictions on manufacturers’ communications regarding off-label use, and if we do not market our products for their approved indications, we may be subject to enforcement action for off-label marketing.

The FDA and DOJ impose stringent restrictions on manufacturers’ communications regarding off-label use, and if we market our products for unapproved indications, we may be subject to enforcement action for off-label marketing.

Violations of such requirements may lead to investigations alleging violations of the Food, Drug and Cosmetic Act and other statutes, including the False Claims Act and other federal and state health care fraud and abuse laws as well as state consumer protection laws.

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• restrictions on product distribution or use;

• holds on clinical trials;

• requirements to conduct post-marketing studies or clinical trials;

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• fines, restitution or disgorgement of profits or revenues;

• suspension or withdrawal of marketing approvals;

• suspension or revocation of marketing approvals;

• damage to relationships with any potential collaborators;

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Several other countries, including the U.K., have enacted similar anti-kickback, fraud and abuse, and healthcare laws and regulations.

• The federal False Claims Act imposes civil penalties, including civil whistleblower or qui tam actions, against individuals or entities for knowingly presenting, or causing to be presented, to the federal government, claims for payment that are false or fraudulent or making a false statement to avoid, decrease or conceal an obligation to pay money to the federal government.

• The federal False Claims Act imposes civil penalties, including civil whistleblower or qui tam actions, against individuals or entities for knowingly presenting, or causing to be presented, claims for payment of government funds that are false or fraudulent or making a false statement to avoid, decrease or conceal an obligation to pay money to the federal government.

The government and qui tam relators have brought False Claims Act actions against pharmaceutical companies on the theory that their practices have caused false claims to be submitted to the government.

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Exclusion, suspension and debarment from government funded healthcare programs would significantly impact our ability to commercialize, sell or distribute any drug.

If any of the physicians or other providers or entities with whom we expect

to do business are found to be not in compliance with applicable laws, they may be subject to criminal, civil or administrative sanctions, including exclusions from government funded healthcare programs.

If any of the physicians or other providers or entities with whom we expect to do business are found to be not in compliance with applicable laws, they may be subject to criminal, civil or administrative sanctions, including exclusions from government funded healthcare programs.

Inadequate funding for or other disruptions to government agencies could hinder or otherwise prevent those agencies from performing normal business functions on which the operation of our business may rely, which could negatively impact our business.

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These have, among other things, reduced Medicare payments to several types of providers, including hospitals, imaging centers and cancer treatment centers, and increased the statute of limitations period for the government to recover overpayments to providers.

Further legislative, regulatory and other legal changes remain possible.

President Biden signed into law the Inflation Reduction Act of 2022 (the “IRA”) on August 16, 2022, which includes several provisions to lower prescription drug costs for Medicare patients and reduce drug spending by the federal government.

Among other things, the IRA has multiple provisions that may impact the prices of drug products that are both sold into the Medicare program and throughout the United States.

Starting in 2023, a manufacturer of a drug or biological product covered by Medicare Parts B or D must pay a rebate to the federal government if the drug product’s price increases faster than the rate of inflation.

This calculation is made on a drug product by

drug product basis and the amount of the rebate owed to the federal government is directly dependent on the volume of a drug product that is paid for by Medicare Parts B or D.

Additionally, starting in payment year 2026, the U.S.

Centers for Medicare and Medicaid Services (“CMS”), will negotiate drug prices annually for a select number of single source Part D drugs without generic or biosimilar competition.

CMS will also negotiate drug prices for a select number of Part B drugs starting for payment year 2028.

Negotiations will occur for products that have been on the market for seven years for Part D drugs and for eleven years for Part B drugs.

For example, several healthcare reform initiatives culminated in the enactment of the IRA, which includes several provisions to lower prescription drug costs for Medicare patients and reduce drug spending by the federal government.

Among other things, the IRA requires HHS to directly negotiate the selling price of a statutorily specified number of drugs and biologics each year that the U.S.

Centers for Medicare and Medicaid Services (“CMS”) reimburses under Medicare Part B and Part D.

Negotiations will occur for high expenditure single-source biological products that have been on the market for 11 years (seven years for single-source drugs).

Revised prices will take effect two years after these negotiations occur.

If a drug product is selected by CMS for negotiation, it is expected that the revenue generated from such drug will decrease.

It is unknown what form any future changes or any law would take under the Trump Administration and how or whether it may affect our business in the future.

We expect that changes or additions to the ACA, the Medicare and Medicaid programs, changes allowing the federal government to directly negotiate drug prices and changes stemming from other healthcare reform measures, especially with regard to healthcare access, financing or other legislation in individual states, could have a material adverse effect on the healthcare industry.

In addition, the ACA has also been subject to challenges in the courts, which remain ongoing.

For 2026, the first year in which negotiated prices become effective, CMS selected 10 high-cost Medicare Part D products in 2023, negotiations began in 2024, and the negotiated price for each product has been announced.

In addition, CMS has selected and announced the negotiated price for 15 additional Medicare Part D drugs which will become effective in 2027.

For 2028, an additional 15 drugs, which may be covered under either Medicare Part B or Part D, the negotiated price will be effective, and for 2029 and subsequent years, 20

Part B or D drug negotiated prices will be effective.

The negotiated prices have represented, and will continue to represent, a significant discount from average prices to wholesalers and direct purchasers.

The IRA also imposes rebates on Medicare Part B and Part D drugs whose prices have increased at a rate greater than the rate of inflation, and in 2024, CMS finalized regulations for the Medicare Part B and Part D inflation rebates.

The IRA permits the Secretary of HHS to implement many of these provisions through guidance, as opposed to regulation, for the initial years.

Manufacturers that fail to comply with the IRA may be subject to various penalties, including civil monetary penalties.

The current administration is pursuing policies to reduce regulations and expenditures across government including at HHS, which include the FDA and CMS, and related agencies.

For example, on May 12, 2025, President Trump issued an Executive Order that, among other things, required HHS, within 30 days, to establish and communicate to drug manufacturers MFN price targets designed to bring drug prices for American patients in line with those in comparably developed nations.

If significant progress towards MFN pricing is not achieved, the Executive Order requires HHS to propose a rulemaking to implement MFN pricing.

Recently, on December 23, 2025, CMS issued proposed regulations to establish, under the Center for Medicare and Medicaid Innovation, two mandatory MFN demonstration models under Medicare Parts B and D, respectively.

If these rules or other MFN pricing rules are finalized, they are likely to reduce prices of at least some drugs in the United States, if they are also sold in comparator countries.

Even if we do not market drugs in such countries, we will be indirectly affected if our drugs competed with drugs whose prices were reduced as a result of MFN pricing initiatives.

At the state level, individual states are increasingly aggressive 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.

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or Member State level may result in significant additional requirements or obstacles that may increase our operating costs.

An example of reform measures is the forthcoming EU pharmaceutical legislation revision, which intends to change – among other things – the regulatory data protection regime and the orphan designation regime.

The final text of the reform proposal is expected to be endorsed and published in the first half of 2026 and, after a transition period, the new legislation is expected to start to apply from mid-2028.

We are subject to anti-corruption laws, as well as export control laws, customs laws, sanctions laws and other laws governing our operations.

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We are also subject to other laws and regulations governing our international operations, including regulations administered by the governments of the U.S.

and the U.K., and authorities in the E.U., including applicable export control regulations, economic sanctions on countries and persons, customs requirements and currency exchange regulations, collectively referred to as the "Trade Control laws".

There is no assurance that we will be completely effective in ensuring our compliance with all applicable anti-corruption laws, including the FCPA, the Bribery Act or other legal requirements, including Trade Control laws.

If we are not in compliance

with the FCPA, the Bribery Act and other anti-corruption laws or Trade Control laws, we may be subject to criminal and civil penalties, disgorgement and other sanctions and remedial measures, and legal expenses, which could have an adverse impact on our business, financial condition, results of operations and liquidity.

If we are not in compliance with the FCPA, the Bribery Act and other anti-corruption laws or Trade Control laws, we may be subject to criminal and civil penalties, disgorgement and other sanctions and remedial measures, and legal expenses, which could have an adverse impact on our business, financial condition, results of operations and liquidity.

Likewise, any investigation of any potential violations of the FCPA, the Bribery Act, other anti-corruption laws or Trade Control laws by U.S., U.K.

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If we do not meet the ESG expectations of government agencies, our investors, customers and other stakeholders, we could experience reduced demand for our products, loss of customers, and other negative impacts on our business and results of operations.

The Company’s reputation or relationships with its stakeholders and other third parties could also be adversely impacted as a result of, among other things, (i) stakeholder or third-party perceptions of statements, if any, made by the Company, its employees, agents, any industry trade associations, or other third parties;

The Company’s reputation or relationships with its stakeholders and other third parties could also be adversely impacted as a result of, among other things, (i) stakeholder or third-party perceptions of certain statements, if any, made by the Company, its employees, agents, any industry trade associations, or other third parties;

or (ii) public pressure from investors or policy groups to change the Company's policies.

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Certain regulators, such as the SEC and various state agencies, as well as nongovernmental organizations and other private actors have filed lawsuits under various securities and consumer protection laws alleging that certain ESG statements, goals or standards were misleading, false or otherwise deceptive.

On the other hand, the Company could face criticism from certain “anti-ESG” parties if it were to make environmental or social commitments or pursue certain environmental or social initiatives that are alleged to be inherently political or polarizing in nature and could subject the Company to pressure in the media or through other means, which could adversely affect our reputation, business, financial performance, market access and growth.

Additionally, certain employment practices and social initiatives are the subject of scrutiny by both those calling for the continued advancement of such policies, as well as those who believe they should be curbed, including government actors, and the complex regulatory and legal frameworks applicable to such initiatives continue to evolve.

We cannot be certain of the impact of such regulatory, legal and other developments on our business.

More recent political developments could mean that we could face criticism from certain “anti-ESG” parties, including various governmental agencies, if we were to make environmental or social commitments or pursue certain environmental or social initiatives that are alleged to be inherently political or polarizing in nature and could subject the Company to pressure in the media or through other means, which could adversely affect our reputation, business, financial performance, market access and growth.

Risks Related to Our Intellectual Property, Cybersecurity and Data Privacy

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These factors may limit the scope of protection we achieve, increasing our vulnerability to competition and undermining the commercial potential of our products.

Moreover, if we license technology or product candidates from third parties in the future, we may have limited control over the preparation, filing, prosecution, or enforcement of the associated patents, leaving us vulnerable to decisions that may not align with our goals or interests.

For example, under our License Agreement with Akeso, patent prosecution and enforcement in the Licensed Territory are subject to consultation and cooperation with Akeso.

If we cannot align on our patent strategy, this could impact the patentability or enforcement of the licensed intellectual property.

Actions or statements during patent prosecution outside of the Licensed Territory could significantly influence the validity of any patent obtained within the Licensed Territory, potentially undermining our competitive position.

with our goals or interests.

For example, under the License Agreement, patent prosecution and enforcement in the Licensed Territory are subject to consultation and cooperation with Akeso.

Actions or statements during patent prosecution outside of the Licensed Territory could significantly influence the prosecution of any patent application within the Licensed Territory.

Additionally, Akeso owned patents and patent applications, which are non-exclusively licensed to Summit under the License Agreement, are under the control of Akeso.

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and elsewhere may also result in clinical trial data submitted as part of a marketing authorization application becoming publicly available.

Such developments could enable other companies to use our clinical trial data to assist in their own product development and to obtain marketing authorizations in the E.U.

developments could enable other companies to use our clinical trial data to assist in their own product development and to obtain marketing authorizations in the E.U.

and in other jurisdictions.

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Despite our best efforts, our attempts to prevent third parties from circumventing our intellectual property and other rights may ultimately be unsuccessful.

Additionally, any failure to take the required actions, such as paying necessary

maintenance fees or addressing administrative formalities, could jeopardize the longevity and enforceability of our patents, further exposing us to risks of market erosion and reduced exclusivity.

Additionally, any failure to take the required actions, such as paying necessary maintenance fees or addressing administrative formalities, could jeopardize the longevity and enforceability of our patents, further exposing us to risks of market erosion and reduced exclusivity.

The issuance of a patent is not conclusive as to its inventorship, scope, validity or enforceability, and our owned and licensed patents may be challenged in the courts or patent offices in the United States and abroad.

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Competitors may infringe our patents, trademarks, copyrights or other intellectual property rights.

To counter infringement or unauthorized use, we may be required to initial legal claims or enforcement actions, which can be expensive and time-consuming.

To counter infringement or unauthorized use, we may be required to initiate legal claims or enforcement actions, which can be expensive and time-consuming.

Such actions are not always successful.

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Absent a license, we could be forced, including by court order, to cease commercializing the infringing technology or product entirely.

In addition, we could be found liable for monetary damages, including treble damages and attorneys’ fees, particularly if we are found to have willfully infringed a patent or other intellectual property right.

In addition, we could be found liable for monetary damages, including treble damages and attorneys’ fees, particularly if we are found to have willfully

infringed a patent or other intellectual property right.

A finding of infringement could prevent us from commercializing our product candidates or force us to cease some of our business operations, which could materially harm our business.

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To safeguard these trade secrets, we employ non-disclosure and confidentiality agreements with parties who have access to them, such as our employees, corporate collaborators, outside scientific collaborators, contract manufacturers, consultants, advisors and other third parties.

However, despite these measures, we cannot guarantee that we have executed these agreements with each party that may have or have had access to our trade secrets or that the agreements we have executed will provide adequate protection.

However, despite these reasonable measures, we cannot guarantee that we have executed these agreements with each party that may have or have had access to our trade secrets or that the agreements we have executed will provide adequate protection.

Even with these protections, any party with whom we have executed such an agreement may breach their obligations and disclose our proprietary or confidential information, including our trade secrets unlawfully.

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If our information technology systems or data, or those of third parties upon whom we rely or interact, are or were compromised, we could experience material adverse consequences resulting from such compromise.

In the ordinary course of our business, we and the third parties we rely on collect, receive, store, use, transfer, make accessible, dispose of, transmit, disclose or otherwise process proprietary, confidential and sensitive information, personal information, personal health information, participant-study-health-related data, proprietary information, intellectual property, and trade secrets (collectively, "sensitive data").

In addition, we rely on service providers to establish and maintain appropriate information technology and data security protections to operate critical business systems (such as cloud-based infrastructure and systems, personnel email, as well as data storage and management systems).

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In addition, these obligations may require us to change our business plans.

Outside the U.S., an increasing number of laws, regulations and industry standards apply to data privacy and security.

An increasing number of laws, regulations and industry standards apply to data privacy and security.

For example, the E.U.’s GDPR, imposes strict requirements on the processing of personal data.

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For example, the California Consumer Privacy Act, as amended by the California Privacy Rights Act (the “CCPA”), imposes obligations on business to which it applies.

These obligations include, but are not limited to, providing specific disclosures in privacy notices and affording California residents certain rights related to their personal data.

allows for statutory fines for noncompliance (up to $7,500 per violation).

These obligations include, but are not limited to, providing

specific disclosures in privacy notices and affording California residents certain rights related to their personal data.

The CCPA allows for statutory fines for noncompliance (up to $7,500 per violation).

While the CCPA contains limited exceptions for clinical trial data, the CCPA’s implementation standards and enforcement practices are likely to remain uncertain for the foreseeable future.

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HIPAA, as amended by HITECH, and their respective implementing regulations impose significant obligations on covered entities and business associates to safeguard the privacy, security, and integrity of individually identifiable health information, also known as protected health information.

On April 8, 2025, the U.S.

Department of Justice implemented a final rule carrying out Executive Order 14117, “Preventing Access to U.S.

Sensitive Personal Data and Government-Related Data by Countries of Concern or Covered Persons (the “Rule”), which places restrictions on certain bulk data transactions involving "Countries of Concern" (China, Hong Kong, Iran, Cuba, Russia, North Korea, and Venezuela) and covered individuals (i.e., individuals and entities located in or controlled by individuals or entities located in those jurisdictions).

The Rule's restrictions could significantly impact some of our business activities, such as clinical related vendor engagements and collaborations and partnerships.

If there is no lawful manner, including applicable exemptions under the Rule, for us to transfer sensitive personal information of U.S.

persons to persons or entities located in Countries of Concern, we may face significant business disruptions, including needing to change our operations by re-locating portions of our business, personnel and/or data processing activities to other jurisdictions (such as the United States) and having to engage with vendors and partners located outside Countries of Concern.

Although we endeavor to comply with all applicable data privacy and security obligations, we may at times fail to do so or may be perceived to have failed to do so.

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We or the third parties we rely on may be adversely affected by natural disasters and our business continuity and disaster recovery plans may not adequately protect us from a serious disaster.

The changing nature, frequency, and severity of natural disasters and extreme weather events such as tornadoes, hurricanes flooding, extreme heat, and wildfires pose a risk to Company facilities, assets, and programs, as well as those of third parties on

whom we rely.

Natural disasters could severely disrupt our operations and have a material adverse effect on our business, results of operations, financial condition and prospects.

If a natural disaster, power outage, or other event occurred that prevented us from using all or a significant portion of our offices or prevented a third party on whom we rely from using its facilities, or if a disaster damaged critical infrastructure that we and third parties rely upon, or if a disaster otherwise disrupted operations, it may be difficult or, in certain cases, impossible, for us to continue our business for extended periods period of time.

If a natural disaster, power outage, or other event occurred that prevented us, or a third party on whom we rely, from using offices or other facilities, or if a disaster damaged infrastructure critical to such offices or facilities, or if a disaster otherwise disrupted operations, it may be difficult or, in certain cases, impossible, for us to continue our business for extended periods period of time.

In addition to operational impacts, natural disasters could significantly affect clinical trial participants, institutions, doctors, and supporting staff.

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Our employees may engage in misconduct or other improper activities, including non-compliance with regulatory standards and requirements, which could cause significant liability for us and harm our reputation.

We may be exposed to the risk of employee fraud or other misconduct, including intentional failures to comply with FDA or Office of Inspector General regulations or similar regulations of comparable non-U.S.

regulatory authorities, provide accurate information to the FDA or comparable non-U.S.

regulatory authorities, comply with manufacturing standards we have established, comply with federal and state healthcare fraud and abuse laws and regulations and similar laws and regulations established and enforced by comparable non-U.S.

regulatory authorities, report financial information or data accurately or disclose unauthorized activities to us.

We may be exposed to the risk of employee fraud or other misconduct, including intentional failures to (i) comply with FDA or Office of Inspector General regulations or similar regulations of comparable non-U.S.

regulatory authorities, (ii) provide

accurate information to the FDA or comparable non-U.S.

regulatory authorities, (iii) comply with manufacturing standards we have established, comply with federal and state healthcare fraud and abuse laws and regulations and similar laws and regulations established and enforced by comparable non-U.S.

regulatory authorities, (iv) report financial information or data accurately or (v) disclose unauthorized activities to us.

Employee misconduct could also involve the improper use of information obtained in the course of clinical trials, which could result in regulatory sanctions and serious harm to our reputation, or a request for the reimbursement of expenses that were not incurred.

It is not always possible to identify and deter employee misconduct, and the precautions we take to detect and prevent this activity may not be effective in controlling unknown or unmanaged risks or losses or in protecting us from governmental investigations or other actions or lawsuits stemming from a failure to be in compliance with such laws, standards or regulations.

If any such actions are instituted against us, and we are not successful in

defending ourselves or asserting our rights, those actions could have a significant impact on our business and results of operations, including the imposition of significant fines and other sanctions.

If any such actions are instituted against us, and we are not successful in defending ourselves or asserting our rights, those actions could have a significant impact on our business and results of operations, including the imposition of significant fines and other sanctions.

Key personnel have been, and may continue to be, difficult to attract and retain.

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In addition, many of our clinical development, operational and program management positions require deep technical expertise, and it can be particularly challenging to identify and attract candidates and retain employees possessing such expertise.

We have experienced, and may continue to experience, attrition in certain key positions.

We have experienced, and may continue to experience, attrition across the company.

If we are unable to hire sufficient numbers of qualified employees or retain and motivate existing employees, our business and operating results would be harmed.

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If he sells, or indicates an intention to sell, substantial amounts of shares in the public market, the trading price of our shares could decline.

We are a “large accelerated filer” and the reduced disclosure requirements applicable to “non-accelerated filers,” and, starting in the first fiscal quarter of 2025, "smaller reporting companies" previously available to us no longer apply.

As of June 30, 2024, the market value of our common stock that was held by non-affiliates exceeded $700 million, and as a result, we now qualify as a “large accelerated filer.” As such, we incur significant additional expenses in complying with the Sarbanes-Oxley Act of 2002 and rules implemented by the SEC.

As a large accelerated filer, we are subject to certain disclosure requirements that are applicable to other public companies that were not applicable to us as a “non-accelerated filer” and “smaller reporting company.” We have incurred and will continue to incur significant legal, accounting and other expenses that we did not previously incur.

In addition, the Sarbanes-Oxley Act, the Dodd-Frank Act, the listing requirements of the Nasdaq Stock Market and other applicable securities rules and regulations impose various requirements on public companies, including the establishment and maintenance of effective disclosure and financial controls and corporate governance practices.

Our management and other personnel devote a substantial amount of time to these compliance initiatives.

Moreover, these rules and regulations increase our legal and financial compliance costs and make some activities more time-consuming and costly.

Additionally, if we or our independent registered public accounting firm identifies deficiencies in our internal control over financial reporting that are deemed to be material weaknesses, the market price of our stock could decline and we could be subject to sanctions or investigations by the SEC or other regulatory authorities, which would require additional financial and management resources.

Additionally, we expect that our loss of “non-accelerated filer” and “smaller reporting company” status will require additional attention from management and will result in increased costs to us, which could include higher legal fees, accounting fees and fees associated with investor relations activities, among others.

If we fail to maintain an effective system of internal control over financial reporting, we may not be able to accurately report our financial results or prevent fraud.

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Any failure to implement required new or improved controls, or difficulties encountered in their implementation could cause us to fail to meet our reporting obligations.

In addition, any testing by us conducted in connection with Section 404 of the Sarbanes-Oxley Act, or Section 404, or any subsequent testing by our independent registered public accounting firm, as and when required, may reveal deficiencies in our internal controls over financial reporting that are deemed to be material weaknesses or that may require prospective or retroactive changes to our financial statements or identify other areas for further attention or improvement.

In addition, any testing by us conducted in connection with Section 404 of the Sarbanes-Oxley Act, or Section 404, or any subsequent

testing by our independent registered public accounting firm, as and when required, may reveal deficiencies in our internal controls over financial reporting that are deemed to be material weaknesses or that may require prospective or retroactive changes to our financial statements or identify other areas for further attention or improvement.

Inferior internal controls could also cause investors to lose confidence in our reported financial information, which could have a negative effect on the trading price of our shares of common stock.

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Accordingly, both state and federal courts have jurisdiction to entertain such claims.

To prevent having to litigate claims in multiple jurisdictions and the threat of inconsistent or contrary rulings by different courts, among other

considerations, our restated certificate of incorporation provides that, unless we consent in writing to the selection of an alternative forum, the federal district courts of the U.S.

To prevent having to litigate claims in multiple jurisdictions and the threat of inconsistent or contrary rulings by different courts, among other considerations, our restated certificate of incorporation provides that, unless we consent in writing to the selection of an alternative forum, the federal district courts of the U.S.

shall, to the fullest extent permitted by law, be the sole and exclusive forum for the resolution of any claims arising under the Securities Act.

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Our management has broad discretion in the use of our cash and cash equivalents and could spend our cash in ways that do not improve our results of operations or enhance the value of our shares of common stock.

The failure by our management to apply these funds effectively could result in financial losses that could have a material adverse effect on our business, cause the market price of our shares of common stock to decline and delay the development of our product candidates.

If our management team were to fail to apply these funds effectively, such failure could result in financial losses that could have a material adverse effect on our business, cause the market price of our shares of common stock to decline and delay the development of our product candidates.

We may complete a future acquisition that may not achieve intended results or could increase the number of our outstanding shares or amount of outstanding debt or result in a change of control.

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

What changed 10-K

Item 1A. Risk Factors