Item 1A. Risk Factors

An investment in our American Depositary Shares ("ADSs") involves a high degree of risk. You should carefully consider the risks described below, and all other information appearing elsewhere in this Annual Report, including our consolidated financial statements and the related notes hereto, before making an investment decision regarding our securities. The occurrence of any of the events or developments described below could harm our business, financial condition, results of operations and growth prospects. The risks and uncertainties described below are not the only ones we face. Additional risks and uncertainties not presently known to us may also adversely affect our business.

Risks Related to Our Financial Position and Need for Capital

We have incurred significant losses in every year since our inception. We may continue to incur losses over the next several years and may never achieve or maintain profitability.

While we are a commercial-stage biotechnology company, we have incurred net losses in each year since our inception. Our net losses were $35.5 million, $51.1 million and $55.3 million for the years ended December 31, 2025, 2024 and 2023, respectively. We had an accumulated deficit of $831.3 millionas of December 31, 2025. We have funded our operations to date primarily with proceeds from the public and private offerings of our ordinary and preferred shares and convertible debt securities, debt financing, and payments from our collaboration partners.

While we have received regulatory approval for KIMMTRAK for mUM in the United States, the EU, and certain other significant jurisdictions, we do not have approvals for any other indications or in any other jurisdictions for KIMMTRAK, or have approvals for our other product candidates. Biopharmaceutical product development is a highly speculative undertaking and involves a substantial degree of risk. Since inception, we have focused substantially all of our efforts and financial resources on developing our drug discovery platform and research and development of our product candidates. We have not obtained regulatory approvals for any of our product candidates, other than KIMMTRAK for the treatment of mUM in 39 countries, and there is no assurance that we will obtain further approvals in the future for KIMMTRAK in additional indications or countries or for any of our other product candidates. We expect to continue to incur significant expenses and operating losses over the next several years and for the foreseeable future.

These losses will adversely impact our shareholders’ equity and net assets and may fluctuate significantly from quarter to quarter and year to year. We anticipate that our expenses will increase substantially if, and as, we:

•further commercialize KIMMTRAK and any future product candidate for which we may obtain marketing approval in the United States and expanded territories and countries;

•continue our ongoing and planned development of our clinical stage programs and our preclinical pipeline assets;

•initiate pre-clinical studies and clinical trials for any additional product candidates that we may pursue in the future;

•seek regulatory approvals for our existing and potential future product candidates that successfully complete clinical trials;

•build a portfolio of product candidates through the discovery, development, or acquisition or in-license of drugs, product candidates or technologies;

•maintain, protect, enforce and expand our intellectual property portfolio;

•acquire or in-license other product candidates, intellectual property and technologies;

•hire additional clinical, regulatory, scientific and sales and marketing personnel;

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•add operational, financial and management information systems and personnel, including personnel to support commercial development of KIMMTRAK, our product development and planned future commercialization efforts of existing and future product candidates; and

•incur additional legal, accounting and other expenses associated with operating as a public company.

To become and remain profitable, we must succeed in developing and commercializing KIMMTRAK in additional countries and indications, and other products that generate significant revenue. This will require us to be successful in a range of challenging activities, including continuing to market and sell KIMMTRAK and any future products for which we may obtain regulatory approval, our global regulatory submissions for any existing or future product candidates that we may pursue, obtaining regulatory approval, procuring commercial-scale manufacturing, as well as discovering or acquiring and then developing additional product candidates. We may never succeed in these activities and, even if we do, may never generate revenues that are significant enough to achieve profitability.

Because of the numerous risks and uncertainties associated with drug development, we are unable to accurately predict the timing or amount of expenses or when, or if, we will be able to achieve profitability. Our expenses could increase beyond our expectations if we are required by the FDA, the EMA, or other regulatory authorities to perform studies in addition to those we currently expect, if issues associated with KIMMTRAK arise following regulatory approval, or if there are any delays in the initiation and completion of our clinical trials or the development of tebentafusp or any future product candidates.

Even if we do achieve profitability, we may not be able to sustain or increase profitability on a quarterly or annual basis. Our failure to become and remain profitable would decrease the value of our ADSs and could impair our ability to raise capital, maintain our research and development efforts, expand our business or continue our operations. A decline in the value of our ADSs could also cause you to lose all or part of your investment.

Our future prospects are highly dependent on our ability to continue to successfully develop and execute our commercialization strategies for KIMMTRAK and any future products for which we may obtain regulatory approval. Failure to do so would adversely impact our financial condition and prospects.

We focus substantial resources on the commercialization of KIMMTRAK and will have to focus substantial resources on the commercialization of any product for which we may obtain regulatory approval in the future. Our ability to generate significant medicine revenues and to achieve commercial success in the near-term will initially depend on our ability to continue to commercialize KIMMTRAK.

We are focusing a significant portion of our commercial activities and resources on KIMMTRAK, and we believe our ability to grow our long-term revenues, and a significant portion of the value of our company, relates to our ability to successfully commercialize KIMMTRAK in the United States and Europe. We expect to develop our commercial teams further and to continue to develop commercialization strategies in order to continue to successfully commercialize KIMMTRAK in the longer term. There are many factors that could cause commercialization of KIMMTRAK to be unsuccessful, including many that are outside our control. For example, the mUM patient population could be lower than estimated, patient and physician acceptance and adoption of KIMMTRAK could change, and physicians’ willingness to prescribe or patients’ willingness to take KIMMTRAK could change, each of which could limit the commercial potential of KIMMTRAK. Thus, there is uncertainty regarding the full commercial potential of KIMMTRAK. If the continued commercialization of KIMMTRAK became less successful or was perceived as disappointing, the price of our ADSs could decline significantly and long-term success of the medicine and our company could be harmed.

Our ability to continue to generate revenues from KIMMTRAK and any other product candidates, if approved, is subject to being considered safe, effective, and having advantages over other therapies, and attaining and maintaining significant market acceptance among physicians, patients and healthcare payors.

KIMMTRAK, and other product candidates that we may develop or acquire, may not attain or maintain market acceptance among physicians, patients, healthcare payors or the medical community, even if they receive marketing approval by relevant authorities. We believe that the degree of continued market acceptance and our ability to continue to generate revenues from KIMMTRAK will depend on a number of factors, including:

•timing of competitive medicines;

•continued efficacy and safety of KIMMTRAK;

•continued projected growth of the markets in which KIMMTRAK competes;

•the extent to which physicians diagnose and treat the conditions that KIMMTRAK is approved to treat;

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•prevalence and severity of any side effects;

•if and when we are able to obtain regulatory approvals for additional indications for KIMMTRAK;

•continued acceptance by patients, physicians and applicable specialists;

•availability of, and ability to maintain, coverage and adequate reimbursement and pricing from government and other third-party payors;

•potential or perceived advantages or disadvantages of KIMMTRAK over alternative treatments, including cost of treatment and relative convenience and ease of administration;

•strength of sales, marketing and distribution support;

•the price of KIMMTRAK, both in absolute terms and relative to alternative treatments;

•impact of past and limitation of future medicine price increases;

•our ability to maintain a continuous supply of KIMMTRAK for commercial sale;

•the effect of current and future healthcare laws;

•disruptions caused by health pandemics or epidemics, including the extent to which physicians and patients delay visits or writing or filling prescriptions for KIMMTRAK;

•the performance of third-party distribution partners, over which we have limited control; and

•medicine labeling or medicine insert requirements of the FDA or other regulatory authorities

Our ability to grow KIMMTRAK sales will be affected by the success of our sales, access, marketing and medical strategies. If KIMMTRAK or any other products that we may seek approval for, or acquire, fail to attain, or fail to maintain, market acceptance, we may not be able to generate significant revenue to sustain profitability, which would have a material adverse effect on our business, results of operations, financial condition and prospects (including, possibly, the value of our ADSs).

Our revenues from KIMMTRAK may be significantly reduced by both existing and future legislation for drug pricing reforms requiring the payment of rebates.

Effective January 1, 2023, the 2021 Infrastructure Investment and Jobs Act requires certain manufacturers to refund the government for discarded amounts of certain drugs covered under Medicare Part B from single use containers. The CMS finalized a rule in November 2022 that characterizes the dead loss volume that exceeds an applicable percentage in small vial drug administration as wastage and thus trigger a corresponding rebate. However, in November 2023, CMS published the 2024 physician fee schedule that identified KIMMTRAK as a medicine that meets the criteria for unique circumstances under the 2021 Jobs Act, and was granted an increased applicable percentage of unused or discarded product volume subject to refund to CMS of 45%, as opposed to the 10% used for medicines without these unique circumstances. Therefore, we do not currently expect to be required to make refund payments under the CMS Rule. If CMS changes its position regarding our exemption and the final rule applies to KIMMTRAK, our revenue in the United States could be impacted.

Additional drug pricing legislation has or may be proposed in further countries, which may reduce our future revenues if such laws are made effective in those countries.

We may require substantial additional funding to achieve our business goals. If we are unable to obtain this funding when needed and on acceptable terms, we could be forced to delay, limit or terminate our product development efforts.

Developing biopharmaceutical products is expensive and time-consuming, and we may require substantial additional capital to conduct research, pre-clinical testing and human studies, establish pilot scale and commercial scale manufacturing processes and facilities, and establish and develop quality control, regulatory, marketing, sales and administrative capabilities to support our existing programs and pursue potential additional programs. We are also responsible for the payments to third parties of expenses that may include milestone payments, license maintenance fees and royalties, including in connection with certain agreements with academic institutions or other companies with respect to the in-licensing or acquisition of their intellectual property rights. Because the outcome of any pre-clinical or clinical development and regulatory approval process is highly uncertain, we cannot reasonably estimate the actual amounts necessary to successfully complete the development, regulatory approval process and commercialization of any existing or future product candidates. In addition, global macroeconomic factors, such as supply chain disruptions and rising inflation, may increase these expenses beyond what we currently anticipate.

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As of December 31, 2025, we had working capital (defined as total current assets less total current liabilities) of $750.0 million, cash and cash equivalents of $467.7 million, and marketable securities of $396.4 million. We expect that our existing cash and cash equivalents with the inclusion of expected revenue for KIMMTRAK will provide sufficient funds to continue to meet our liabilities as they fall due and for at least 12 months from the issuance of our Annual Report. However, it is possible that our revenue may be lower than our estimates, that our costs will be higher than expected, that our operating plan may change as a result of many factors currently unknown to us, and that we may need to seek additional funds sooner than planned, through public or private equity or debt financings or other sources, such as strategic collaborations or license and development agreements. In addition, we may seek additional capital due to favorable market conditions or strategic considerations, even if we believe we have sufficient funds for our current or future operating plans.

Any additional fundraising efforts for us may divert our management from their day-to-day activities, which may adversely affect our ability to develop and commercialize product candidates that we may identify and pursue. Moreover, such financing may result in dilution to our shareholders, imposition of debt covenants and repayment obligations, or other restrictions that may affect our business. Our future funding requirements will depend on many factors, including, but not limited to:

•our ability to continue to execute our commercialization strategies for KIMMTRAK and, if approved, our other product candidates;

•progress, timing, scope and costs of our clinical trials, including the ability to timely initiate clinical sites, enroll subjects and manufacture product candidates for our ongoing, planned and potential future clinical trials;

•time and costs required to perform research and development to identify and characterize new product candidates from our research programs;

•the time and cost necessary to pursue regulatory authorizations and approvals that may be required by regulatory authorities to execute clinical trials or commercialize our products;

•our ability to have clinical and commercial products successfully manufactured consistent with FDA, European Commission and other authorities’ regulations;

•amount of sales and other revenues from product candidates that we may commercialize, if any, including the selling prices for such potential products and the availability of adequate third-party coverage and reimbursement for patients;

•sales and marketing costs associated with commercializing our products, if approved, including the cost and timing of scaling our marketing and sales capabilities;

•cost of building, staffing and validating our manufacturing processes, which may include capital expenditure;

•terms and timing of any revenue we may receive under existing or future collaborations;

•costs of operating as a public company;

•time and cost necessary to respond to technological, regulatory, political and market developments;

•costs of filing, prosecuting, defending and enforcing any patent claims and other intellectual property rights;

•the impact of global and macroeconomic factors, including supply chain disruptions, fluctuating interest rates and volatility in the capital markets;

•costs, associated with, and terms and timing of, any future any potential acquisitions, strategic collaborations, licensing agreements or other arrangements that we may establish; and

•inability of clinical sites to enroll patients as healthcare capacities are required to cope with natural disasters, epidemics or other health system emergencies.

A change in the outcome of any of these or other variables with respect to the development, regulatory approval and commercialization of any of our current and future product candidates could significantly change the costs and timing associated with the development and commercialization of that product candidate. Furthermore, our operating plans may change in the future, and we may need additional funds to meet operational needs and capital requirements associated with such operating plans.

Additional funds may not be available when we need them, on terms that are acceptable, or at all, particularly in light of recently worsening macroeconomic conditions, including supply chain disruptions, fluctuating interest rates and volatility in the capital markets. If adequate funds are not available to us on a timely basis, we may be required to delay, limit or terminate one or more research or development programs or the commercialization of any product candidates or be unable to expand operations or otherwise capitalize on business opportunities, as desired, which could materially affect our business, prospects, financial condition and results of operations.

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Raising additional capital may cause dilution to our existing shareholders, restrict our operations or cause us to relinquish valuable rights.

We may seek additional capital through a combination of public and private equity offerings, debt financings, strategic partnerships and alliances and licensing arrangements. In addition, we may seek additional capital due to favorable market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans. To the extent that we raise additional capital through the sale of equity, convertible debt securities or other equity-based derivative securities, your ownership interest will be diluted, and the terms may include liquidation or other preferences that adversely affect your rights as holder of ADSs. Any indebtedness we incur would result in increased fixed payment obligations and could involve restrictive covenants, such as limitations on our ability to incur additional debt, limitations on our ability to acquire or license intellectual property rights and other operating restrictions that could adversely impact our ability to conduct our business. Any debt or additional equity financing that we raise may contain terms that are not favorable to us or our shareholders. Furthermore, the issuance of additional securities, whether equity or debt, by us, or the possibility of such issuance, may cause the market price of our ADSs to decline and existing shareholders may not agree with our financing plans or the terms of such financings. If we raise additional funds through strategic partnerships, collaborations, and alliances and licensing arrangements with third parties, we may have to relinquish valuable rights to our intellectual property, technologies or our product candidates, or grant licenses on terms unfavorable to us.

Risks Related to KIMMTRAK and the Development of Our Product Candidates

In order to increase adoption and sales of KIMMTRAK, we will need to continue developing our commercial organization as well as recruit and retain qualified field representatives.

In order to continue and expand our commercialization of KIMMTRAK, we must continue to build our sales, marketing, distribution, managerial and other non-technical capabilities. We currently have limited resources compared to some of our competitors, and the continued development of our own commercial organization to market our medicines and any additional medicines we may acquire will be expensive and time-consuming. We also cannot be certain that we will be able to continue to successfully develop this capability.

As there was no prior treatment approved for mUM before KIMMTRAK was approved, we have been and continue to be required to expend significant time and resources to train our sales force to be credible and able to educate physicians on the benefits of prescribing and pharmacists dispensing KIMMTRAK. Furthermore, we must train our sales force to ensure that a consistent and appropriate message about KIMMTRAK is being delivered to our potential customers. We may experience turnover of the sales representatives that we hired or will hire, requiring us to train new sales representatives. If we are unable to effectively train our sales force and equip them with effective materials, including medical and sales literature to help them inform and educate physicians about the benefits of KIMMTRAK and their proper administration and label indication, as well as our patient assistance programs, our efforts to continue to successfully commercialize KIMMTRAK could be put in jeopardy, which could have a material adverse effect on our financial condition, share price and operations.

The incidence and prevalence for target patient populations for some of our product candidates have not been established with precision. If the market opportunities for our product candidates are smaller than we estimate, our revenue and ability to achieve profitability will be adversely affected, possibly materially.

The total addressable market opportunity for KIMMTRAK and our other programs will ultimately depend upon, among other things, acceptance by the medical community and patient access, product pricing and reimbursement as well as expansion into additional markets. The number of patients with cancers, solid tumors, HIV, and chronic HBV and test positive for HLA-A*02:01 may turn out to be lower than expected, patients may not be otherwise amenable to treatment with our products, or new patients may become increasingly difficult to identify or gain access to, all of which would adversely affect our results of operations and our business. We may not be successful in our efforts to identify additional product candidates. Due to our limited resources and access to capital, we must prioritize development of certain product candidates, which may prove to be the wrong choice and may adversely affect our business prospects. These and other factors may limit the estimated opportunities size of our products and product candidates. If the market opportunities for our product candidates are smaller than we estimate, our revenue and ability to achieve profitability will be adversely affected, possibly materially.

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We are heavily dependent on the success of our ImmTAX platform to identify and develop product candidates. If we or our collaborators are unable to successfully develop and commercialize our platforms or experience significant delays in doing so, our business may be harmed.

We are heavily dependent on the success of our ImmTAX platform technology, KIMMTRAK and the product candidates currently in our core programs. Our ImmTAC, ImmTAV and ImmTAAI platforms were developed from the foundation of our ImmTAX platform and are our primary platform technologies. Our commercial prospects will be heavily dependent on product candidates identified and developed using our ImmTAX platform. To date, we have invested substantially all of our efforts and financial resources to identify, acquire intellectual property for, and develop our ImmTAX platform technology and our programs, including conducting pre-clinical studies, as well as early- and late-stage clinical trials and commercialization of KIMMTRAK that emerged from the ImmTAX platform and providing general and administrative support for these operations.

We may not be successful in our efforts to further develop our ImmTAX platform technology and current product candidates. With the exception of KIMMTRAK, which has been approved by the FDA, European Commission, and other regulatory authorities, we are not permitted to market or promote any of our product candidates until we receive regulatory approval from the FDA, European Commission or comparable foreign regulatory authorities, and we may never receive such regulatory approval for any of our product candidates. Each of our product candidates will require significant additional clinical development, management of preclinical, clinical, and manufacturing activities, regulatory approval, adequate manufacturing supply, a commercial organization, and significant marketing efforts before we generate any revenue from product sales, if at all.

We, and the third parties on whom we rely in part for sales, marketing and distribution capabilities, may not be able to continue to effectively market, sell and distribute KIMMTRAK or effectively market, sell and distribute our other product candidates, if approved.

We have invested, and expect to continue to invest, significant financial and management resources to further develop internal sales, distribution and marketing capabilities of product candidates, some of which in territories prior to any confirmation that the product candidate will be approved in that territory.

We utilize a hybrid model that includes an in-house sales force in the United States and contracted resources in the United States and Europe, and we have engaged third parties and may engage additional third parties to provide services related to the marketing of KIMMTRAK and our product candidates. We have entered into agreements with Syneos Health, Inc.("Syneos"), Er-Kim, Medison, and other third parties, to develop our commercial infrastructure for the commercial launch and continued sale of KIMMTRAK, including to potentially retain, train and deploy a direct sales force, but we do not have control over third parties beyond contractual agreements. There can be no assurance that the capabilities of the Syneos sales organization or other third parties will be more effective than an internally developed sales organization. In addition, Syneos can terminate our agreement under certain circumstances. If Syneos or other third parties fail to hire, train, and retain qualified sales personnel, market our product successfully or on a cost-effective basis or otherwise terminates our relationship, our ability to generate revenue will be limited and we will need to identify and retain an alternative organization or develop our own sales and marketing capability. This could involve significant delays and costs, including the diversion of our management’s attention from other activities. We may also need to retain additional consultants or external service providers to assist us in sales, marketing and distribution functions, and may be unsuccessful in retaining such services on acceptable financial terms or at all.

For our other product candidates, there are risks involved with both establishing our own sales and marketing capabilities and entering into arrangements with third parties to perform these services. For example, recruiting and training a commercial organization 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. 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 product candidates on our own include:

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

•the inability of sales personnel to obtain access to physicians or educate adequate numbers of physicians on the benefits of prescribing any future product that we may develop;

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

•evolving social media practices and the risk of noncompliance with regulations applicable to our business, as well as the spread of negative publicity regarding our products or product candidates on various social media channels; and

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

If we enter into arrangements with third parties to perform sales, marketing and distribution services, our revenue from sale of therapies or the profitability from these revenue streams is likely to be lower than if we were to market and sell any product candidates that we develop ourselves. In addition, we may not be successful in entering into arrangements with third parties to sell and market our product candidates or may be unable to do so on terms that are favorable to us. We likely will have little control over such third parties and any of them may fail to devote the necessary resources and attention to sell and market our product candidates effectively. If we do not establish sales and marketing capabilities successfully, either on our own or in collaboration with third parties, we may not be successful in commercializing our product candidates.

KIMMTRAK and our other product candidates, even if approved for commercial sale, may fail to achieve the degree of market acceptance by physicians, patients, third-party payors and others in the medical community necessary for continued commercial success.

KIMMTRAK and our other product candidates, even if approved for commercial sale by the FDA, the European Commission or other comparable regulatory authorities, may not achieve or maintain market acceptance among physicians, patients, hospitals, including pharmacy directors, and third-party payors and, ultimately, may not become or remain commercially successful. The degree of market acceptance of KIMMTRAK or any of our product candidates, if approved for commercial sale, will depend on a number of factors, including:

•the clinical indications for which our medicines are approved;

•physicians, hospitals, cancer treatment centers, and patients considering our medicines as a safe and effective treatment;

•hospitals and cancer treatment centers establishing the infrastructure required for the administration of the medicine;

•the potential and perceived advantages of our medicines over alternative treatments;

•the prevalence and severity of any side effects, including cytokine release syndrome ("CRS"), for which KIMMTRAK has a boxed warning recommending at least 16 hours of patient monitoring after each of the first three infusions, and as clinically indicated thereafter;

•product labeling or product insert requirements of the FDA, the European Commission or other regulatory authorities;

•limitations or warnings contained in the labeling approved by the FDA or the European Commission;

•the timing of market introduction of our medicines compared to competitive products;

•the cost of treatment in relation to alternative treatments;

•the amount of upfront costs or training required for physicians to administer our medicines;

•the pricing of our products and the availability of coverage and adequate reimbursement by third-party payors and government authorities;

•the willingness of patients to pay out-of-pocket in the absence of comprehensive coverage and adequate reimbursement by third-party payors and government authorities;

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•relative convenience and ease of administration, including as compared to alternative treatments and competitive therapies; and

•the effectiveness of our sales and marketing efforts and distribution support.

Our efforts to educate physicians, patients, third-party payors and others in the medical community on the benefits of our products, if approved, may require significant resources and may never be successful. Such efforts may require more resources than are typically required due to the complexity and uniqueness of our product candidates. Even if our products achieve market acceptance, we may not be able to maintain that market acceptance over time, including if new products or technologies are introduced that are more favorably received than our products, are more cost effective or render our products obsolete. Because we expect sales of KIMMTRAK and our other product candidates, if approved, to generate substantially all of our revenue for the foreseeable future, the failure of our medicines to find or maintain market acceptance would harm our business and could require us to seek additional financing.

We may be unable to successfully complete additional large-scale, pivotal clinical trials for any product candidates we develop.

We may be unable to successfully complete additional large-scale, pivotal clinical trials for any product candidates we develop. We cannot be sure that issues will not arise that require us to suspend or terminate our clinical trials. Guidance we have received from the FDA or other regulatory authorities on clinical trial design is subject to change. These regulatory authorities could change their position, including, on the acceptability of our trial designs or the clinical endpoints selected, which may require us to complete additional clinical trials or impose stricter approval conditions than we currently expect. Successful completion of our clinical trials is a prerequisite to submitting a BLA to the FDA and a MAA to the EMA, for each product candidate and, consequently, the ultimate approval and commercial marketing of each product candidate. We do not know whether any of our future clinical trials will begin on time or ever be completed on schedule, if at all.

If we are required to conduct additional clinical trials or other testing of our product candidates beyond those that we currently contemplate, if we are unable to successfully complete clinical trials of our product candidates or other testing, if the results of these trials or tests are not positive or are only modestly positive or if there are safety concerns, we may:

•be delayed in obtaining marketing approval for our product candidates;

•not obtain marketing approval at all;

•obtain approval for indications or patient populations that are not as broad as intended or desired;

•be subject to post-marketing testing requirements; or

•have the product removed from the market after obtaining marketing approval.

Our product candidates utilize a novel mechanism of action and involve novel targets which may result in greater research and development expenses, regulatory issues that could delay or prevent approval, or discovery of unknown or unanticipated adverse effects.

Our product candidates utilize novel mechanisms of action and involve novel targets which may result in greater research and development expenses, regulatory issues that could delay or prevent approval, or discovery of unknown or unanticipated adverse effects. Our ImmTAX platform uses advanced computational models in tight integration with our structural biology, protein engineering, affinity maturation and binding efficacy capabilities to predict and design the compounds that will achieve the most desirable characteristics, including potency, selectivity, bioavailability, and drug-like properties. A disruption in any of these capabilities may have significant adverse effects in our abilities to expand our ImmTAX platform, and we cannot predict whether we will continue to have access to these capabilities in the future to support our ImmTAX platform. In addition, there can be no assurance that we will be able to rapidly identify, design and synthesize the necessary compounds or that these or other problems related to the development of this novel mechanism will not arise in the future, which may cause significant delays or raise problems we may not be able to resolve.

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Regulatory approval of novel product candidates such as ours can be more expensive, riskier and take longer than for other, more well-known or extensively studied pharmaceutical or biopharmaceutical product candidates due to our and regulatory authorities’ lack of experience with them. The novelty of our mechanism of action may lengthen the regulatory review process, require us to conduct additional studies or clinical trials, increase our development costs, lead to changes in regulatory positions and interpretations, delay or prevent approval and commercialization of our product candidates or lead to significant post-approval limitations or restrictions. The novel mechanism of action also means that fewer people are trained in or experienced with product candidates of this type, which may make it more difficult to find, hire and retain personnel for research, development and manufacturing positions. Because our soluble bispecific T cell receptors ("TCRs") utilize a novel mechanism of action and involve novel targets, there is also an increased risk that we may discover previously unknown or unanticipated adverse effects during our pre-clinical studies and clinical trials. Any such events could adversely impact our business prospects, financial condition and results of operations.

Although we intend to explore other therapeutic opportunities in addition to the product candidates that we are currently developing, we may fail to identify viable new product candidates for clinical development for a number of reasons. If we fail to identify additional potential product candidates, our business could be materially harmed.

Research programs to pursue the development of our existing and planned product candidates for additional indications and to identify new product candidates and disease targets require substantial technical, financial and human resources, whether or not they are ultimately successful. For example, we develop various protein models and make predictions as to how molecules might target antigens, with subsequent validation efforts in our labs and labs of our CROs. There can be no assurance that we will find potential additional targets using this approach, that any such targets will be tractable, or that such clinical validations will be successful. Our research programs may initially show promise in identifying potential indications and/or product candidates, yet fail to yield results for clinical development for a number of reasons, including:

•the research methodology used may not be successful in identifying potential indications and/or product candidates;

•potential product candidates may, after further study, be shown to have harmful adverse effects or other characteristics that indicate they are unlikely to be effective products; or

•it may take greater human and financial resources than we will possess to identify additional therapeutic opportunities for our product candidates or to develop suitable potential product candidates through internal research programs, thereby limiting our ability to develop, diversify and expand our product portfolio.

Because we have limited financial and human resources, we intend to initially focus on research programs and product candidates for a limited set of indications. As a result, we may forgo or delay pursuit of opportunities with other product candidates or for other indications that later prove to have greater commercial potential or a greater likelihood of success. Our resource allocation decisions may cause us to fail to capitalize on viable commercial products or profitable market opportunities.

Accordingly, there can be no assurance that we will ever be able to identify additional therapeutic opportunities for our product candidates or to develop suitable potential product candidates through internal research programs, which could materially adversely affect our future growth and prospects. We may focus our efforts and resources on potential product candidates or other potential programs that ultimately prove to be unsuccessful.

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Clinical product development involves a lengthy and expensive process, with an uncertain outcome.

While we plan to pursue additional regulatory approvals, it is uncertain whether we will receive further marketing approval for tebentafusp beyond the approval we have received for KIMMTRAK for mUM in the United States, the EU, Canada and certain other territories. For example, it is impossible to predict when or if tebentafusp for the treatment of advanced melanoma or adjuvant uveal (ocular) melanoma, brenetafusp, IMC-I109V, IMC-M113V, IMC-P115C, IMC-R117C, IMC-S118AI, or IMC-U120AI, or any of our future product candidates, will prove effective and safe in humans or will receive regulatory approval. Before obtaining marketing approval from regulatory authorities for the sale of any product candidate, we must complete pre-clinical studies 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 uncertain as to outcome. A failure of one or more clinical trials can occur at any stage of testing. The outcome of pre-clinical development testing and early clinical trials may not be predictive of the success of later clinical trials, and interim results of a clinical trial do not necessarily predict final results. Moreover, pre-clinical and clinical data are often susceptible to varying interpretations and analyses, and many companies that have believed their product candidates performed satisfactorily in pre-clinical studies and clinical trials have nonetheless failed to obtain marketing approval of their product candidates. Our pre-clinical studies and future clinical trials may not be successful.

We also rely, and expect to continue to rely in part, on outside vendors (for example, independent contractors and CROs) to conduct, supervise or monitor some or all aspects of clinical trials involving our products. We will have less control over the timing and other aspects of these clinical trials than if we conducted them entirely on our own. If we fail to commence or complete, or experience delays in, any of our planned clinical trials, the price of our ADSs and our ability to conduct our business as currently planned could be harmed.

We currently rely on, and expect to continue to rely in part on, CMOs to manufacture our products for clinical trials. If they fail to commence or complete, or experiences delays in, manufacturing our products and product candidates, our planned clinical trials will be delayed, which will adversely affect our stock price and our ability to conduct our business as currently planned.

If we are not able to obtain, or if there are delays in obtaining, required regulatory approvals for our product candidates, we will not be able to commercialize, or will be delayed in commercializing, our product candidates, and our ability to generate revenue will be materially impaired.

Our product candidates and the activities associated with their development and commercialization, including their design, testing, manufacture, safety, efficacy, recordkeeping, labeling, storage, approval, advertising, promotion, sale, distribution, import and export are subject to comprehensive regulation by the FDA and other regulatory authorities in the United States and by comparable authorities in the EU and other territories. Before we can commercialize further product candidates, we must obtain marketing approval. Currently, the majority of our product candidates are in development, and we have not received approval to market any of our product candidates from regulatory authorities, with the exception of KIMMTRAK for mUM. It is possible that our product candidates, including any product candidates we may seek to develop in the future, will never obtain regulatory approval. We have only limited experience in filing and supporting the applications necessary to gain regulatory approvals and expect to rely on third-party CROs and/or regulatory consultants to assist us in this process. Obtaining regulatory approval requires the submission of extensive pre-clinical and clinical data and supporting information to the various regulatory authorities for each therapeutic indication to establish the product candidate’s safety and efficacy. Obtaining regulatory approval also requires the submission of information about the product manufacturing process to, and inspection of manufacturing facilities by, the relevant regulatory authority. Our product candidates may not be effective, may be only moderately effective or may prove to have undesirable or unintended side effects, toxicities or other characteristics that may preclude our obtaining marketing approval or prevent or limit commercial use. In addition, regulatory authorities may find fault with our manufacturing process or facilities or that of third-party contract manufacturers. We may also face greater than expected difficulty in manufacturing our product candidates.

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The process of obtaining regulatory approvals, both in the United States, the EU and other territories, is expensive and often takes many years. If the FDA, EMA, or a comparable foreign regulatory authority requires that we perform additional pre-clinical or clinical trials, approval, if obtained at all, may be delayed. The length of such a delay varies substantially based upon a variety of factors, including the type, complexity and novelty of the product candidates involved. Changes in marketing approval policies during the development period, changes in or the enactment of additional statutes or regulations, or changes in regulatory review for each submitted application, may cause delays in the approval or rejection of an application. The FDA and comparable authorities in other countries have 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. Furthermore, our ability to enroll patients could be delayed by future health pandemics or epidemics, and it is not possible to know whether these will impact us or the extent and scope of such delays at this point. In addition:

•the FDA, EMA and European Commission or comparable foreign regulatory authorities may disagree with the design or implementation of our clinical trials;

•we may be unable to demonstrate to the satisfaction of the FDA, EMA and European Commission or comparable foreign regulatory authorities that a product candidate is safe and effective for its proposed indication or a related companion diagnostic is suitable to identify appropriate patient populations;

•the results of clinical trials may not meet the level of statistical significance required by the FDA, EMA and European Commission or comparable foreign regulatory authorities for approval;

•we may be unable to demonstrate that a product candidate’s clinical and other benefits outweigh its safety risks;

•the FDA, EMA and European Commission or comparable foreign regulatory authorities may disagree with our interpretation of data from pre-clinical studies or clinical trials;

•the data collected from clinical trials of our product candidates may not be sufficient to support the submission a BLA or other submission or to obtain regulatory approval in the United States or elsewhere;

•the FDA or comparable foreign regulatory authorities may find deficiencies with or fail to approve the manufacturing processes or facilities of third-party manufacturers with which we contract for clinical and commercial supplies; and

•the approval policies or regulations of the FDA, EMA and European Commission or comparable foreign regulatory authorities may significantly change such that our clinical data are insufficient for approval.

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

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.

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Positive results from early pre-clinical studies of our product candidates are not necessarily predictive of the results of later pre-clinical studies and any future clinical trials of our product candidates. If we cannot replicate the positive results from our earlier pre-clinical studies of our product candidates in our later pre-clinical studies and future clinical trials, we may be unable to successfully develop, obtain regulatory for and commercialize our product candidates.

Any positive results from our pre-clinical studies of our product candidates may not necessarily be predictive of the results from required later pre-clinical studies and clinical trials. Similarly, even if we are able to complete our planned pre-clinical studies or any future clinical trials of our product candidates according to our current development timeline, the positive results from such pre-clinical studies and clinical trials of our product candidates may not be replicated in subsequent pre-clinical studies or clinical trial results. In addition, positive results in later stage clinical trials of one of our product candidates in an indication may not be predictive of the safety or efficacy of our other product candidates in other indications, even if they employ a similar mechanism of action.

Many companies in the pharmaceutical and biotechnology industries have suffered significant setbacks in late-stage clinical trials after achieving positive results in early-stage development, and we cannot be certain that we will not face similar setbacks. These setbacks have been caused by, among other things, pre-clinical and other nonclinical findings made while clinical trials were underway, or safety or efficacy observations made in pre-clinical studies and clinical trials, including previously unreported adverse events. Moreover, preclinical, nonclinical and clinical data are often susceptible to varying interpretations and analyses and many companies that believed their product candidates performed satisfactorily in pre-clinical studies and clinical trials nonetheless failed to obtain FDA and/or European Commission approval.

Interim, “top-line” and preliminary data from our clinical trials that we announce or publish from time to time may change as more patient data become available and are subject to audit and verification procedures that could result in material changes in the final data.

From time to time, we may publish interim, “top-line” or preliminary data from our planned clinical trials. Interim data from clinical trials that we may complete are subject to the risk that one or more of the clinical outcomes may materially change as patient enrollment continues and more patient data become available. Preliminary or “top-line” data also remain subject to audit and verification procedures that may result in the final data being materially different from the preliminary data we previously published. As a result, interim and preliminary data should be viewed with caution until the final data are available. Differences between preliminary or interim data and final data could significantly harm our business prospects and may cause the trading price of our ADSs to fluctuate significantly.

We may incur additional costs or experience delays in completing, or ultimately be unable to complete, the development and commercialization of our product candidates.

We may experience delays in completing our pre-clinical studies and initiating or completing clinical trials, and we may experience numerous unforeseen events during, or as a result of, any future clinical trials that we could conduct that could delay or prevent our ability to receive marketing approval or commercialize our product candidates, including:

•regulators, IRBs, or ethics committees may not authorize us or our investigators, or provide the required positive opinion, to commence a clinical trial or conduct a clinical trial at a prospective trial site;

•we may experience delays in reaching, or fail to reach, agreement on acceptable terms with prospective trial sites and prospective CROs, the terms of which can be subject to extensive negotiation and may vary significantly among different CROs and trial sites;

•clinical trials of our product candidates may produce negative or inconclusive results, and we may decide, or regulators may require us, to conduct additional pre-clinical studies or clinical trials or we may decide to abandon product development programs;

•the number of patients required for clinical trials of our product candidates may be larger than we anticipate, enrollment in these clinical trials may be slower than we anticipate, or participants may drop out of these clinical trials or fail to return for post-treatment follow-up at a higher rate than we anticipate;

•our third-party contractors may fail to comply with regulatory requirements or meet their contractual obligations to us in a timely manner, or at all, or may deviate from the clinical trial protocol or drop out of the trial, which may require that we add new clinical trial sites or investigators;

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•we may elect to, or regulators or IRBs or ethics committees may require us or our investigators to, 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;

•the cost of clinical trials of our product candidates may be greater than we anticipate;

•the supply or quality of our product candidates or other materials necessary to conduct clinical trials of our product candidates may be insufficient or inadequate; and

•our product candidates may have undesirable side effects or other unexpected characteristics, causing us or our investigators, regulators or IRBs or ethics committees to suspend or terminate the trials, or reports may arise from pre-clinical or clinical testing of other cancer therapies that raise safety or efficacy concerns about our product candidates.

We could encounter delays if a clinical trial is suspended or terminated by us, by the IRBs or ethics committees of the institutions at which such trials are being conducted, by the Data Safety Monitoring Board ("DSMB"), for such trial or by the FDA or other regulatory authorities. Such authorities may impose such a suspension or termination or clinical hold due to a number of factors, including failure to conduct the clinical trial in accordance with regulatory requirements or our clinical protocols, inspection of the clinical trial operations or trial site by the FDA or other regulatory authorities, unforeseen safety issues or adverse side effects, failure to demonstrate a benefit from using a product, changes in governmental regulations or administrative actions or lack of adequate funding to continue the clinical trial. Many of the factors that cause, or lead to, a delay in the commencement or completion of clinical trials may also ultimately lead to the denial of regulatory approval of our product candidates. Further, the FDA or comparable foreign regulatory authorities may disagree with our clinical trial design and our interpretation of data from clinical trials, or may change the requirements for approval even after it has reviewed and commented on the design for our clinical trials.

Our product development costs will also increase if we experience delays in testing or regulatory approvals. We do not know whether any of our future clinical trials will begin as planned, or whether any of our current or future clinical trials will need to be restructured or will be completed on schedule, if at all. Significant delays in pre-clinical studies or clinical trials also could shorten any periods during which we may have the exclusive right to commercialize our product candidates or allow our competitors to bring products to market before we do and impair our ability to successfully commercialize our product candidates and may harm our business and results of operations. Any delays in our pre-clinical or future clinical development programs may harm our business, financial condition and prospects significantly.

If we experience delays or difficulties in the enrollment of patients in clinical trials, our receipt of necessary regulatory approvals could be delayed or prevented.

We may not be able to initiate or continue clinical trials for our product candidates if we are unable to locate and enroll a sufficient number of eligible patients to participate in these trials as required by the FDA or similar regulatory authorities or the EU’s requirements. In particular, because we will be deploying our drug discovery platform across a broad target space, our ability to enroll eligible patients may be limited or may result in slower enrollment than we anticipate. In addition, some of our competitors have ongoing clinical trials for product candidates that treat the same indications as our product candidates, and patients who would otherwise be eligible for our clinical trials may instead enroll in clinical trials of our competitors’ product candidates. Furthermore, our ability to enroll patients may be significantly delayed by public health crises, such as health pandemics or epidemics.

In addition to the competitive trial environment, the eligibility criteria of our planned clinical trials will further limit the pool of available study participants as we will require that patients have specific characteristics that we can measure to assure their cancer is either severe enough or not too advanced to include them in a study. Additionally, the process of finding patients may prove costly. We also may not be able to identify, recruit and enroll a sufficient number of patients to complete our clinical studies because of the perceived risks and benefits of the product candidates under study, the availability and efficacy of competing therapies and clinical trials, the proximity and availability of clinical trial sites for prospective patients, and the patient referral practices of physicians. If patients are unwilling to participate in our studies for any reason, the timeline for recruiting patients, conducting studies and obtaining regulatory approval of potential products may be delayed.

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We may also engage third parties to develop companion diagnostics for use in our clinical trials, but such third parties may not be successful in developing such companion diagnostics, furthering the difficulty in identifying patients with the targeted genetic mutations for our clinical trials. Further, if we are required to develop companion diagnostics and are unable to include patients with the targeted genetic mutations, this could compromise our ability to seek participation in the FDA’s expedited review and development programs, including Breakthrough Therapy Designation and Fast Track Designation, or otherwise to seek to accelerate clinical development and regulatory timelines. Patient enrollment may be affected by other factors including:

•the severity of the disease under investigation;

•the eligibility criteria for the clinical trial in question;

•the availability of an appropriate genomic screening test;

•the perceived risks and benefits of the product candidate under study;

•the efforts to facilitate timely enrollment in clinical trials;

•the patient referral practices of physicians;

•the ability to monitor patients adequately during and after treatment;

•the proximity and availability of clinical trial sites for prospective patients; and

•factors we may not be able to control, such as current or potential pandemics or epidemics that may limit patients, principal investigators or staff or clinical site availability.

Our planned clinical trials or those of our future collaborators may reveal significant adverse events not seen in our pre-clinical or nonclinical studies and may result in a safety profile that could inhibit regulatory approval or market acceptance of any of our product candidates.

Before obtaining regulatory approvals for the commercial sale of any products, we must demonstrate through lengthy, complex and expensive pre-clinical studies and clinical trials that our product candidates are both safe and effective for use in each target indication. Clinical testing is expensive and can take many years to complete, and its outcome is inherently uncertain. Failure can occur at any time during the clinical trial process. The results of pre-clinical studies and early clinical trials of our product candidates may not be predictive of the results of later-stage clinical trials. In addition, initial success in clinical trials may not be indicative of results obtained when such trials are completed. There is typically an extremely high rate of attrition from the failure of product candidates proceeding through clinical trials. Product candidates in later stages of clinical trials also may fail to show the desired safety and efficacy profile despite having progressed through nonclinical studies and initial clinical trials. A number of companies in the biopharmaceutical industry have suffered significant setbacks in advanced clinical trials due to lack of efficacy or unacceptable safety issues, notwithstanding promising results in earlier trials. Most product candidates that commence clinical trials are never approved as products and there can be no assurance that any of our current or future clinical trials will ultimately be successful or support further clinical development of any of our product candidates.

We may develop future product candidates, in combination with one or more cancer therapies. The uncertainty resulting from the use of our product candidates in combination with other cancer therapies may make it difficult to accurately predict side effects in future clinical trials. See also “We intend to develop tebentafusp, brenetafusp and our other programs, and potentially future product candidates, in combination with other therapies, which exposes us to additional risks.”

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As is the case with many treatments for cancer, infectious diseases and autoimmune diseases, it is likely that there may be side effects associated with the use of our product candidates. If significant adverse events or other side effects are observed in any of our current or future clinical trials, we may have difficulty recruiting patients to our clinical trials, patients may drop out of our trials, or we may be required to abandon the trials or our development efforts of one or more product candidates altogether. We, the FDA or other applicable regulatory authorities, or an IRB or ethics committee may suspend or terminate clinical trials of a product candidate at any time for various reasons, including a belief that subjects in such trials are being exposed to unacceptable health risks or adverse side effects. Some potential therapeutics developed in the biotechnology industry that initially showed therapeutic promise in early-stage trials have later been found to cause side effects that prevented their further development. Even if the side effects do not preclude the product from obtaining or maintaining marketing approval, undesirable side effects may inhibit market acceptance of the approved product due to its tolerability versus other therapies. Any of these developments could materially harm our business, financial condition and prospects.

We are at risk of a clinical hold at any time based on the evaluation of the data and information submitted to the governing regulatory authorities.

Our clinical trials may become subject to a clinical hold based on the evaluation of data and information submitted to the governing regulatory authorities. For example, in 2020, we received notice from the FDA of a partial clinical hold on our brenetafusp clinical trial after the second patient (with baseline elevated risk factors for pulmonary embolus) experienced a fatal adverse event of respiratory failure due to multiple pulmonary emboli 24 hours after receiving the first dose (0.3 mcg). In accordance with our own internal guidelines, we put our clinical trial on hold to investigate this unexplained death and informed the FDA. The FDA subsequently put our clinical trial on a partial clinical hold and allowed us the option to continue dosing the first patient. After autopsy, including expert review, and other investigations, the primary investigator concluded that the cause of death was respiratory failure and not related to study drug. We modified the trial protocol to add a lower dose cohort and additional screening and on-treatment precautions. The FDA accepted our changes and removed the partial clinical hold enabling the trial to continue.

In the future, a clinical trial may be suspended or terminated by us, our collaborators, the FDA or other comparable foreign regulatory authorities due to a number of factors, including failure to conduct the clinical trial in accordance with regulatory requirements or our clinical protocols, inspection of the clinical trial operations or trial site by the FDA or other comparable foreign regulatory authorities resulting in the imposition of a clinical hold, unforeseen safety issues or adverse side effects, failure to demonstrate a benefit from using a product candidate, changes in governmental regulations or administrative actions or lack of adequate funding to continue the clinical trial. If we experience delays in the completion of, or if we terminate, any clinical trial of our product candidates, the commercial prospects of our product candidates will be harmed, and our ability to generate medicine revenues from any of these product candidates will be delayed or reduced. Any delays in completing our clinical trials in the future, whether or not related to FDA concerns, will increase our costs, slow down our medicine development and approval process and jeopardize our ability to commence sales and generate revenues.

Moreover, principal investigators for our clinical trials may serve as scientific advisors or consultants to us from time to time and receive compensation in connection with such services. Under certain circumstances, we may be required to report some of these relationships to the FDA or comparable foreign regulatory authorities. The FDA or comparable foreign regulatory authorities may conclude that a financial relationship between us and a principal investigator has created a conflict of interest or otherwise affected interpretation of the study. The FDA or comparable foreign regulatory authorities may therefore question the integrity of the data generated at the applicable clinical trial site and the utility of the clinical trial itself may be jeopardized. This could result in a delay in approval, or rejection, of our marketing applications by the FDA or comparable foreign regulatory authorities and may ultimately lead to the denial of marketing approval of one or more of our product candidates.

Any of these occurrences may harm our business, financial condition, results of operations and prospects significantly. In addition, many of the factors that cause, or lead to, a delay in the commencement or completion of clinical trials may also ultimately lead to the denial of regulatory approval of our product candidates.

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Our product candidates may cause undesirable side effects or have other properties that could halt their clinical development, prevent their regulatory approval, require expansion of the trial size, limit their commercial potential, or result in significant negative consequences.

Undesirable side effects caused by our product candidates could cause us or regulatory authorities, including IRBs or ethics committees, to interrupt, delay, or halt clinical trials and could result in a more restrictive label or the delay or denial of regulatory approval by the FDA, European Commission or other comparable foreign regulatory authorities. Further, clinical trials by their nature utilize a sample of the potential patient population. With a limited number of subjects and limited duration of exposure, rare and severe side effects of our product candidates may only be uncovered with a significantly larger number of patients exposed to the drug. Because of our planned dose escalation design for our clinical trials, undesirable side effects could also result in an expansion in the size of our clinical trials, increasing the expected costs and timeline of our clinical trials. Additionally, results of our clinical trials could reveal a high and unacceptable severity and prevalence of side effects or unexpected characteristics, which may stem from our therapies specifically or may be due to an illness from which the clinical trial subject is suffering.

For example, our oncology clinical trials include cancer patients who are very sick and whose health is deteriorating, and we expect that additional clinical trials of our other product candidates will include similar patients with deteriorating health. In clinical trials conducted by other companies involving CAR T cells, TCR T or T cell redirecting bispecifics, the most prominent acute toxicities included symptoms thought to be associated with CRS, such as fever, low blood pressure and kidney dysfunction. KIMMTRAK has a boxed warning regarding CRS, recommending patient monitoring for at least 16 hours following the first three infusions, and as clinically indicated thereafter. It is possible that some of these patients may experience similar adverse side effects as were observed in clinical trials conducted by other companies and academic institutions, and that additional patients may die during our clinical trials for various reasons, including as a result of receiving our product candidates, because the patient’s disease is too advanced, or because the patient experiences medical problems that may not be related to our product candidate. Even if the deaths are not related to our product candidate, the deaths could affect perceptions regarding the safety of our product candidate.

Patient deaths and severe side effects caused by our product candidates, or by products or product candidates of other companies that are thought to have similarities with our therapeutic candidates, could result in the delay, suspension, clinical hold or termination of clinical trials by us, the FDA, the national competent authorities of Member States or other regulatory authorities for a number of reasons. If we elect or are required to delay, suspend or terminate any clinical trial of any product candidates that we develop, the commercial prospects of such product candidates will be harmed and our ability to generate revenues from any of these product candidates would be delayed or eliminated. Serious adverse events observed in clinical trials could hinder or prevent market acceptance of the product candidate at issue. Any of these occurrences may harm our business, prospects, financial condition and results of operations significantly.

Our product candidates may have serious and potentially fatal cross-reactivity to other peptides or protein sequences within the body.

Our product candidates may recognize and bind to a peptide unrelated to the target antigen to which it is designed to bind. If this peptide is expressed within normal tissues, our product candidates may target and kill the normal tissue in a patient, leading to serious and potentially fatal adverse effects. Detection of any cross-reactivity may halt or delay any ongoing clinical trials for any TCR-based product candidate and prevent or delay regulatory approval. Unknown cross-reactivity of the TCR binding domain to related proteins could also occur. We have also developed a pre-clinical screening process to identify cross-reactivity of the TCR binders. Any cross-reactivity that impacts patient safety could materially impact our ability to advance our product candidates into clinical trials or to proceed to marketing approval and commercialization.

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We intend to develop tebentafusp, brenetafusp and our other programs, and potentially future product candidates, in combination with other therapies, which exposes us to additional risks.

We intend to develop tebentafusp, brenetafusp and other programs, and may develop future product candidates, for use in combination with one or more currently approved cancer therapies. We continue enrollment in our TEBE-AM Phase 3 trial investigating tebentafusp for the treatment of 2L+ advanced CM as a monotherapy or in combination with an anti-PD(L)1 therapy and in multiple combination arms of our brenetafusp Phase 1/2 clinical trial, including evaluation of brenetafusp in combination with standards of care including checkpoint inhibitors, chemotherapy and tebentafusp. In 2024, we also started randomizing patients with previously untreated advanced melanoma to brenetafusp + nivolumab versus nivolumab or nivolumab + relatlimab, depending on the country, in our PRISM-MEL-301 Phase 3 trial. Even if any product candidate we, or our collaboration partners, develop, was to receive marketing approval or be commercialized for use in combination with other existing therapies, we would continue to bear the risks that the FDA or similar foreign regulatory authorities could revoke approval of the therapy used in combination with our product candidate or that safety, efficacy, manufacturing or supply issues could arise with these existing therapies. Combination therapies are commonly used for the treatment of cancer, and we would be subject to similar risks if we develop any of our product candidates for use in combination with other drugs or for indications other than cancer. This could result in our own products being removed from the market or being less successful commercially.

We may also evaluate brenetafusp and our other programs, or any other future product candidates, in combination with one or more other cancer, infectious disease or autoimmune disease therapies that have not yet been approved for marketing by the FDA, the European Commission or similar foreign regulatory authorities. We will not be able to market and sell brenetafusp and our other programs, or any product candidate we develop in combination with any such unapproved cancer, infectious disease or autoimmune therapies, that do not ultimately obtain marketing approval.

If the FDA, European Commission or similar foreign regulatory authorities do not approve these other drugs or revoke their approval of, or if safety, efficacy, manufacturing, or supply issues arise with, the drugs we choose to evaluate in combination with our or any product candidate we develop, the approval of our product candidates may be delayed and their value may be reduced, which may harm our business, financial condition and prospects.

If we do not achieve our projected development and commercialization goals within the timeframes we announce and expect, the commercialization of our product candidates or any future product candidates may be delayed, and our business will be harmed.

For planning purposes, we estimate the timing of achieving various scientific, clinical, regulatory, and other product development objectives. These milestones may include our expectations regarding the commencement or completion of scientific studies and clinical trials, regulatory submissions or commercialization objectives. From time to time, we may publicly announce the expected timing of some of these milestones, such as the submission of a CTA or IND application, completion of an ongoing clinical trial, the initiation of clinical trials, announcement of trial data, receipt of regulatory approval, or the commercial launch of a product. The achievement of many of these milestones may be affected by factors outside of our control. All of these milestones are based on a variety of assumptions, which may cause the timing of achieving the milestones to vary considerably from our estimates, including:

•our available capital resources or capital constraints we experience;

•the rate of progress, costs, and results of our clinical trials and research and development activities, including the extent of scheduling conflicts with participating clinicians and collaborators;

•our ability to identify and enroll patients who meet clinical trial eligibility criteria;

•our receipt of approvals by the FDA, European Commission and comparable foreign regulatory authorities, and the timing thereof;

•other actions, decisions, or rules issued by regulators;

•our ability to access sufficient, reliable, and affordable supplies of materials used in the manufacture of our product candidates;

•our ability to manufacture and supply clinical trial materials to our clinical sites on a timely basis;

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•the efforts of our collaborators with respect to the commercialization of our approved products, if any; and

•the securing of, costs related to, and timing issues associated with, commercial product manufacturing, as well as sales and marketing activities.

If we fail to achieve announced milestones in the timeframes we expect, the commercialization of our lead product candidate and any other current or future product candidates may be delayed, and our business, results of operations, financial condition, and prospects may be adversely affected.

Due to our limited resources and access to capital, we must, and have in the past decided to, prioritize development of certain product candidates over other potential product candidates. These decisions may prove to have been wrong and may adversely affect our ability to develop our own programs and our attractiveness as a commercial partner and may ultimately have an impact on our commercial success.

Because we have limited resources and access to capital to fund our operations, we must decide which product candidates to pursue and the amount of resources to allocate to each. Our decisions concerning the allocation of research, collaboration, management and financial resources toward particular proprietary molecules in our library, product candidates or therapeutic areas are subject to change over time, and these decisions may not lead to the development of viable commercial products and may divert resources away from better opportunities. For example, in 2025 we decided to pause our IMC-T119C (PRAME-A24) program. Similarly, our decisions to delay, terminate or collaborate with third parties in respect of certain product development programs may also prove not to be optimal and could cause us to miss valuable opportunities. If we make incorrect determinations regarding the market potential of our product candidates, abandon or pause products that we have devoted significant resources toward in favor of other product candidates, or misread trends in the biopharmaceutical industry, in particular for our lead product candidate, our business, financial condition and results of operations could be materially adversely affected.

We conduct clinical trials for our product candidates outside the United States, and the FDA and similar foreign regulatory authorities may not accept data from such trials.

We conduct clinical trials outside the United States including in Australia, New Zealand, Europe, Asia, Latin America and the Middle East, and are likely to continue to do so in these or other foreign jurisdictions. The acceptance of trial data from clinical trials conducted outside the United States by the FDA may be subject to certain conditions. In cases where data from clinical trials conducted outside the United States are intended to serve as the sole basis for marketing approval in the United States, the FDA will generally not approve the application on the basis of foreign data alone unless (i) the data are applicable to the United States population and United States medical practice; (ii) the trials were performed by clinical investigators of recognized competence and (iii) 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. Additionally, the FDA’s clinical trial requirements, including sufficient size of patient populations and statistical powering, must be met. Many foreign regulatory bodies have similar approval requirements. In addition, such foreign trials would be subject to the applicable local laws of the foreign jurisdictions where the trials are conducted. There can be no assurance that the FDA or any similar foreign regulatory authority will accept data from trials conducted outside of the United States or the applicable jurisdiction. If the FDA or any similar foreign regulatory authority does not accept such data, it would result in the need for additional trials, which would be costly and time-consuming and delay aspects of our business plan, and which may result in our product candidates not receiving approval or clearance for commercialization in the applicable jurisdiction.

A variety of risks associated with conducting research and clinical trials in multiple countries and marketing our product candidates internationally could materially adversely affect our business.

Clinical trials are currently being conducted in multiple countries throughout the world, and we plan to globally develop our current and future product candidates. Accordingly, we expect that we will be subject to additional risks related to operating in foreign countries, including:

•differing regulatory requirements in foreign countries;

•unexpected changes in tariffs, trade barriers, price and exchange controls and other regulatory requirements;

•differing standards for the conduct of clinical trials;

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•increased difficulties in managing the logistics and transportation of storing and shipping product candidates produced in the United States or elsewhere and shipping the product candidate to patients in other countries;

•import and export requirements and restrictions;

•economic weakness, including inflation, or political instability in foreign economies and markets, particularly in light of global macroeconomic conditions;

•compliance with tax, employment, immigration and labor laws for employees living or traveling abroad;

•foreign taxes, including withholding of payroll taxes;

•foreign currency fluctuations, which could result in increased operating expenses and reduced revenue, and other obligations incident to doing business in another country;

•difficulties staffing and managing foreign operations;

•workforce uncertainty in countries where labor unrest is more common than in the United Kingdom or the United States;

•differing payor reimbursement regimes, governmental payors or patient self-pay systems, and price controls;

•potential liability under the FCPA, the U.K. Bribery Act 2010, or comparable foreign regulations;

•challenges enforcing or protecting our contractual and intellectual property rights, especially in those foreign countries that do not respect and protect intellectual property rights to the same extent as the United States or the United Kingdom;

•the impacts Brexit may have with respect to recruitment of scientific personnel;

•production shortages resulting from any events affecting raw material supply or manufacturing capabilities abroad; and

•business interruptions resulting from geopolitical actions, including the Ukraine war, the conflict in the Middle East, other wars and acts of terrorism, and the outbreak of and international responses to global health crises.

These and other risks associated with our international operations may materially adversely affect our ability to attain or maintain profitable operations.

Risks Related to the Commercialization of Our Product Candidates

If we fail to comply with manufacturing regulations, our financial results and financial condition will be adversely affected.

KIMMTRAK and our product candidates are biologics and the process of manufacturing our products is complex, highly regulated and subject to multiple risks. We may encounter difficulties in production, particularly with respect to process development, quality control, upscaling or scaling-out of our manufacturing capabilities. If we or any of our third-party manufacturers encounter such difficulties, our ability to provide supply of our product candidates for clinical trials or our products for patients, if approved, could be delayed or stopped, or we may be unable to maintain a commercially viable cost structure.

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Before we can begin commercial manufacture of our products, regulatory authorities must approve marketing applications that identify manufacturing facilities operated by us or third-party manufacturers that have passed regulatory inspection and manufacturing processes that are acceptable to the regulatory authorities. Any failure to follow current Good Manufacturing Practice ("cGMP") or other regulatory requirements or any delay, interruption or other issues that arise in the manufacture, fill and finish, packaging, or storage of our product candidates as a result of a failure of our facilities or the facilities or operations of third parties to comply with regulatory requirements or pass any regulatory authority inspection could significantly impair our ability to develop and commercialize our product candidates, including leading to significant delays in the availability of drug product for our clinical trials or the termination of or hold on a clinical trial, or the delay or prevention of a filing or approval of marketing applications for our product candidates. In addition, our pharmaceutical manufacturing facilities are continuously subject to scheduled and unannounced inspection by the FDA, competent authorities of Member States and other comparable foreign regulatory authorities, before and after product approval, to monitor and ensure compliance with cGMP and other regulations. The facilities used by our contract manufacturers have been approved by the FDA and regulatory authorities in other countries for the manufacture of KIMMTRAK. Although we are not involved in the day-to-day operations of our contract manufacturers, we are ultimately responsible for ensuring that our products are manufactured in accordance with cGMP regulations.

Due to the complexity of the processes used to manufacture our products and product candidates, we may be unable to continue to pass or initially pass federal or international regulatory inspections in a cost-effective manner. For the same reason, any potential third-party manufacturer of our products or our product candidates may be unable to comply with cGMP regulations in a cost-effective manner and may be unable to initially or continue to pass a federal or international regulatory inspection.

Our TCR bispecific product candidates that have been produced and are stored for later use may degrade, become contaminated or suffer other quality defects, which may cause the affected product candidates to no longer be suitable for their intended use in clinical trials or other development activities. If the defective product candidates cannot be replaced in a timely fashion, we may incur significant delays in our development programs that could adversely affect the value of such product candidates. For example, in June 2025, we initiated a global recall for one batch of KIMMTRAK (tebentafusp) relating to an unexpected result in routine stability testing. As of the date of this Annual Report, based on all available data to date, we do not expect there will be a material impact on the supply of KIMMTRAK or our financial statements.

A failure to comply with these requirements may result in regulatory enforcement actions against our manufacturers or us, including fines and civil and criminal penalties, which could result in imprisonment, suspension or restrictions of production, suspension, injunctions, delay or denial of product approval or supplements to approved products, clinical holds or termination of clinical trials, warning or untitled letters, regulatory authority communications warning the public about safety issues with the biologic, refusal to permit the import or export of the products, product seizure, detention, or recall, operating restrictions, suits under the civil False Claims Act ("FCA"), corporate integrity agreements, consent decrees, or withdrawal, suspension or variation of product approval.

If we, or third-party manufacturers with whom we contract, are unable to comply with manufacturing regulations, we may be subject to delay of approval of our product candidates, warning or untitled letters, fines, unanticipated compliance expenses, recall or seizure of our products, total or partial suspension of production and/or enforcement actions, including injunctions, and criminal or civil prosecution. These possible sanctions would adversely affect our business, financial condition, results of operations and growth prospects.

If we are unable to successfully develop and maintain manufacturing processes for KIMMTRAK or our product candidates, or are unable to produce sufficient quantities at acceptable costs, we may be unable to support a clinical trial or be forced to terminate a program, or if we are unable to produce sufficient quantities of our products at acceptable costs, we may be unable to meet commercial demand, lose potential revenue, have reduced margins or be forced to terminate a program.

Due to the complexity of manufacturing KIMMTRAK and our product candidates, we may not be able to manufacture sufficient quantities. Our inability to produce enough of our product candidate at acceptable costs may result in the delay or termination of development programs. With respect to our commercial portfolio, we may not be able to manufacture KIMMTRAK successfully with a commercially viable process or at a scale large enough to support its commercial markets or at acceptable margins.

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The development of commercially viable manufacturing processes typically is very difficult to achieve and is often very expensive and may require extended periods of time. Changes in manufacturing processes (including manufacturing cell lines), equipment or facilities (including moving manufacturing from one of our facilities to another one of our facilities or a third-party facility, or from a third-party facility to one of our facilities) may require us to complete clinical trials to receive regulatory approval of any manufacturing modifications.

Even a developed manufacturing process can encounter difficulties. Problems may arise during manufacturing for a variety of reasons, including human error, mechanical breakdowns, problems with raw materials and cell banks, malfunctions of internal information technology systems, and other events that cannot always be prevented or anticipated. Many of the processes include biological systems, which add significant complexity, as compared to chemical synthesis. We expect that, from time to time, consistent with biotechnology industry expectations, certain production lots will fail to produce product that meets our quality control release acceptance criteria. To date, failure rates for KIMMTRAK have been rare. If the failure rate increased substantially, we could experience increased costs, lost revenue, damage to customer relations, time and expense investigating the cause and, depending upon the cause, similar losses with respect to other lots or products. If problems are not discovered before the product is released to the market, recall and product liability costs may also be incurred.

In order to produce product within our time and cost parameters, we must continue to produce product within our expected success rate and yield expectations. Because of the complexity of our manufacturing processes, it may be difficult or impossible for us to determine the cause of any particular lot failure and we must effectively take corrective action in response to any failure in a timely manner.

We currently rely on third parties for the commercial manufacture of KIMMTRAK. If those manufacturers are unwilling or unable to fulfil their contractual obligations or satisfy demand outside of or in excess of the contractual obligations, we may be unable to meet demand for KIMMTRAK or sell KIMMTRAK at all and we may lose potential revenue. Further, the availability of suitable contract manufacturing capacity at scheduled or optimum times is not certain.

In addition, our manufacturing processes subject us to a variety of federal, state and local laws and regulations governing the use, generation, manufacture, storage, handling and disposal of hazardous materials and wastes resulting from their use. We incur significant costs in complying with these laws and regulations.

We face substantial competition, which may result in others developing or commercializing drugs before or more successfully than us.

The biotechnology and pharmaceutical industries are characterized by rapidly advancing technologies and intense competition. Our competitors may be able to develop other compounds or drugs that are able to achieve similar or better results. Our potential competitors include major multinational pharmaceutical, specialty pharmaceutical, and existing or emerging biotechnology companies, academic research institutions and governmental agencies and public and private research institutions worldwide. Many of our competitors, either alone or with their collaborations, have substantially greater financial, technical and other resources and expertise in research and development, manufacturing, preclinical testing, conducting clinical trials, obtaining regulatory approvals and marketing approved products than we do. Smaller or early-stage companies may also prove to be significant competitors, particularly as they develop novel approaches to treating disease indications that our product candidates are also focused on treating. Established pharmaceutical companies may also invest heavily to accelerate discovery and development of novel therapeutics or to acquire or in-license novel therapeutics that could make the product candidates that we develop obsolete. Mergers and acquisitions in the biotechnology and pharmaceutical industries may result in even more resources being concentrated in our competitors. Competition may increase further as a result of advances in the commercial applicability of technologies and greater availability of capital for investment in these industries. Our competitors also compete with us in recruiting and retaining qualified scientific and management personnel and establishing clinical trial sites and patient enrollment in clinical trials, as well as in acquiring technologies complementary to, or necessary for, our programs. Our competitors, either alone or with collaborative partners, may succeed in developing, acquiring or licensing on an exclusive basis drug or biologic products that are more effective, safer, more easily commercialized or less costly than our product candidates or may develop proprietary technologies or secure patent or other proprietary protection that we may need for the development of our technologies and products. We believe the key competitive factors that will affect the development and commercial success of our product candidates are efficacy, safety, tolerability, reliability, convenience of use, price and reimbursement.

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We face competition from segments of the pharmaceutical, biotechnology and other related markets that pursue the development of TCR-based therapeutics to address unmet needs in cancer including: Adaptimmune Therapeutics plc, Immatics, Adaptive, pure MHC, LLC, BioNTech SE, Genentech, Enara Bio Limited, and Boehringer Ingelheim International GmbH, who are also seeking to identify peptide HLA targets and develop product candidates; Immatics, Anocca AB, T-Knife GmbH, Adaptive, 3T Biosciences, Inc, Regeneron, Takara Bio Inc., AstraZeneca PLC, Lion TCR Pte. Ltd., TCRCure Biopharma Ltd., Corregene Biotechnology Co. LTD, and TScan who are developing TCR-based cell therapies; and Immatics, Molecular Partners AG, 3T Biosciences, Inc., Crossbow Therapeutics, Inc. and CDR-Life Inc. are developing CD3-based TCR bispecific compounds or TCR mimetic antibodies.

In August 2023, Delcath Systems, Inc. announced the approval and U.S. launch of HEPZATO KIT, a liver directed therapy that delivers a high dose of melphalan to the liver via percutaneous hepatic perfusion. This system is marketed in the European Union as a CE Marked medical device under the trade name Delcath Hepatic CHEMOSAT® Delivery System for Melphalan (CHEMOSAT). We are aware of several other companies with product candidates in clinical development, including an anticipated readout from Ideaya Biosciences’ first-line HLA-A*02:01 negative mUM registrational Phase 2/3 clinical trial in 2026. We are also aware of various companies conducting registrational Phase 3 clinical trials in uveal melanoma ("UM"), including Ideaya Biosciences, Inc.’s registrational Phase 3 clinical trial in high-risk neoadjuvant UM, and Replimune Group, Inc. registrational Phase 2/3 clinical trial in immune-checkpoint naïve UM.

We are aware of various companies and academic institutions that are developing TCR transduced cell therapies against a range of pHLA targets, some of which may overlap with product candidates in our pipeline such as PRAME. Specifically in regard to PRAME, we are aware that Immatics, TScan Therapeutics, Inc., and Replay Therapeutics, Inc. (in collaboration with MD Anderson) are conducting Phase 1 clinical trials of PRAME-directed cellular therapies and Immatics has also initiated a Phase 1/2 clinical trial of a PRAME TCRxCD3 half-life extended bispecific approach.

We anticipate that we will continue to face intense and increasing competition as new treatments enter the market and advanced technologies become available. There can be no assurance that our competitors are not currently developing, or will not in the future develop, products that are equally or more effective or are more economically attractive than any of our current or future product candidates. Competing products may gain faster or greater market acceptance than our products, if any, and medical advances or rapid technological development by competitors, including increased use of artificial intelligence-based technologies, may result in our product candidates becoming non-competitive or obsolete before we are able to recover our research and development and commercialization expenses. If we or our product candidates do not compete effectively, it may have a material adverse effect on our business, financial condition and results of operations.

Continued coverage and adequate reimbursement may not be available for KIMMTRAK, or our other current or any future product candidates, which could make it difficult for us to sell profitably, if approved.

Continued market acceptance and sales of KIMMTRAK or any product candidates that we commercialize, if approved, will depend in part on the extent to which reimbursement for these products and related treatments will be available from third-party payors, including government health administration authorities, managed care organizations and private health insurers. While we have established third-party payor coverage for KIMMTRAK in the United States, this coverage may change at any time and we may not be able to maintain it in the future or obtain or maintain similar coverage in additional territories or for additional indications. Third-party payors decide which therapies they will pay for and establish reimbursement levels. Third-party payors in the United States often rely upon Medicare coverage policy and payment limitations in setting their own coverage and reimbursement policies. However, decisions regarding the extent of coverage and amount of reimbursement to be provided for any product candidates that we develop will be made on a payor-by-payor basis. One payor’s determination to provide coverage for a drug does not assure that other payors will also provide coverage for the drug. Additionally, a third-party payor’s decision to provide coverage for a therapy does not imply that an adequate reimbursement rate will be approved. Third-party payors are increasingly challenging the price, examining the medical necessity and reviewing the cost-effectiveness of medical products, therapies and services, in addition to questioning their safety and efficacy. We may incur significant costs to conduct expensive pharmaco-economic studies in order to demonstrate the medical necessity and cost-effectiveness of our product candidates, in addition to the costs required to obtain FDA approvals. Our product candidates may not be considered medically necessary or cost-effective.

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Each payor determines whether or not it will provide coverage for a therapy, what amount it will pay the manufacturer for the therapy, and on what tier of its list of covered drugs, or formulary, it will be placed. The position on a payor’s formulary, generally determines the co-payment that a patient will need to make to obtain the therapy and can strongly influence the adoption of such therapy by patients and physicians. Patients who are prescribed treatments for their conditions and providers prescribing such services generally rely on third-party payors to reimburse all or part of the associated healthcare costs. Patients are unlikely to use our products, and providers are unlikely to prescribe our products, unless coverage is provided and reimbursement is adequate to cover a significant portion of the cost of our products and their administration. Therefore, coverage and adequate reimbursement is critical to new medical product acceptance.

In addition, recently there has been heightened governmental scrutiny over the manner in which manufacturers set prices for their marketed products, which has resulted in several U.S. Congressional inquiries and proposed and enacted federal and state legislation designed to, among other things, bring more transparency to drug pricing, reduce the cost of prescription drugs under government payor programs, and review the relationship between pricing and manufacturer patient programs. For example, the Inflation Reduction Act (IRA) among other things, (1) requires the U.S. Department of Health and Human Services (HHS) to negotiate the price of certain single-source biologics that have been on the market for at least 11 years covered under Medicare as part of the Medicare Drug Price Negotiation Program, and (2) imposes rebates under Medicare Part B and Medicare Part D to penalize price increases that outpace inflation on an annual basis. Each year up to twenty (20) products will be selected by HHS for the Medicare Drug Price Negotiation Program. Products subject to the Medicare Drug Price Negotiation Program are expected to experience a significant reduction in reimbursement from the Medicare program on a per unit basis.

Outside the United States, reimbursement and healthcare payment systems vary significantly by country, and many countries have instituted price ceilings on specific products and therapies. The delivery of health care in the EU, including the establishment and operation of health services and the pricing and reimbursement of medicines, is almost exclusively a matter for national, rather than European Union law and policy. National governments and health service providers have different priorities and approaches to the delivery of health care, and the pricing and reimbursement of products in that country may vary. The European Union provides options for Member States to restrict the range of medicinal products for which their national health insurance systems provide reimbursement and to control the prices of medicinal products for human use. A Member State may approve a specific price for the medicinal product, it may refuse to reimburse a product at the price set by the manufacturer or it may instead adopt a system of direct or indirect controls on the profitability of the company placing the medicinal product on the market. Many Member States also periodically review their reimbursement procedures for medicinal products, which could have an adverse impact on reimbursement status.

Moreover, in order to obtain reimbursement for our products in some European countries, including some Member States, we may be required to compile additional data comparing the cost-effectiveness of our products to other available therapies. This HTA of medicinal products is becoming an increasingly common part of the pricing and reimbursement procedures in some Member States, including those representing the larger markets. The HTA process is the procedure to assess therapeutic, economic and societal impact of a given medicinal product in the national healthcare systems of the individual country. The outcome of an HTA will often influence the pricing and reimbursement status granted to these medicinal products by the competent authorities of individual Member States. The extent to which pricing and reimbursement decisions are influenced by the HTA of the specific medicinal product currently varies between Member States.

On January 12, 2025, the HTA Regulation entered into application through a phased implementation. It is intended to increase cooperation among EU Member States in assessing health technologies, including new medicinal products, by establishing a framework for joint clinical assessments, joint scientific consultations, and the early identification of emerging health technologies. The Regulation permits Member States to use common tools, methodologies, and procedures and requires them to rely on EU‐level joint clinical assessment reports for the clinical components of their national HTA evaluations. Member States, however, remain responsible for assessing non‐clinical aspects, such as economic, ethical, and social considerations, and for making pricing and reimbursement decisions at the national level. As implementation of the HTA Regulation is phased in and key methodological and procedural guidance continues to evolve, there remains uncertainty regarding the evidence requirements, timing, and impact of joint clinical assessments on national reimbursement processes. The new framework may result in additional or differently structured evidentiary expectations, misalignment between assessment and regulatory timelines, or delays in national decisions. If we are unable to maintain favorable pricing and reimbursement status in Member States for product candidates that we may successfully develop and for which we may obtain regulatory approval, any anticipated revenue from and growth prospects for those products in the EU could be negatively affected.

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Legislators, policymakers and healthcare insurance funds in the European Union and the United Kingdom may continue to propose and implement cost-containing measures to keep healthcare costs down, particularly due to the financial strain that the COVID-19 pandemic has placed on national healthcare systems of European countries. These measures could include limitations on the prices we would be able to charge for KIMMTRAK or product candidates that we may successfully develop and for which we may obtain regulatory approval or the level of reimbursement available for these products from governmental authorities or third-party payors. Political, economic and regulatory developments may affect our ability to profitably commercialize KIMMTRAK or our other product candidates, if approved. In addition to continuing pressure on prices and cost containment measures, legislative developments at the European Union or Member State level may result in significant additional requirements or obstacles that may increase our operating costs, delay the commercialization of KIMMTRAK in certain countries, delay the marketing authorization of other product candidates, restrict or regulate post-approval activities and affect our ability to commercialize our product candidates, if approved.

For example, we must enter into pricing agreements with individual Member States in order to be reimbursed for KIMMTRAK in such Member States. For Germany, we had entered into a pricing agreement with the German government for KIMMTRAK. As the sales of KIMMTRAK exceeded the orphan drug threshold (€30 million) in Germany in 2023, German law required a new benefit assessment and renegotiation of the price. The outcome of the benefit assessment remained unchanged; the Federal Joint Committee (G-BA) granted KIMMTRAK a Considerable Added Benefit, and we negotiated and entered into a new pricing agreement with Germany in 2025. In 2025, we also entered into a pricing agreement with France regarding retrospective and future pricing of KIMMTRAK, however we are disputing one element of the agreement related to certain prior periods. We are also negotiating pricing agreements with other Member States, and we cannot guarantee that the price of KIMMTRAK will not change in certain countries in the future. Limitations on our ability to price KIMMTRAK, or our future product candidates, if approved, may have a significant impact on our results of operations.

Further, an increasing number of European Union and other foreign countries use prices for medicinal products established in other countries as “reference prices” to help determine the price of the product in their own territory. Consequently, a downward trend in prices of medicinal products in some countries could contribute to similar downward trends elsewhere.

A primary trend in the U.S. healthcare industry and elsewhere is cost containment. Third-party payors have attempted to control costs by limiting coverage and the amount of reimbursement for particular medications. We cannot be sure that coverage and reimbursement will be available for any drug that we commercialize and, if reimbursement is available, what the level of reimbursement will be. Inadequate coverage and reimbursement may impact the demand for, or the price of, any drug for which we obtain marketing approval. If coverage and adequate reimbursement are not available, or are available only to limited levels, we may not be able to successfully commercialize our current and any future product candidates that we develop. Coverage policies and third party reimbursement rates may change at any time. Even if favorable coverage and adequate reimbursement status is attained for one or more products for which we receive regulatory approval, less favorable coverage policies and reimbursement rates may be implemented in the future.

Additionally, we may use or develop a proprietary diagnostic test for use with certain of our product candidates. We will be required to obtain coverage and reimbursement for this test separate and apart from the coverage and reimbursement we seek for our product candidates, if approved. There is significant uncertainty regarding our ability to obtain coverage and adequate reimbursement for this proprietary diagnostic test for reasons similar to those applicable to our product candidates, which could impact future revenue.

We face potential product liability, and, if successful claims are brought against us, we may incur substantial liability and costs. If the use of our product candidates harms patients, or is perceived to harm patients even when such harm is unrelated to our product candidates, our regulatory approvals could be revoked or otherwise negatively impacted and we could be subject to costly and damaging product liability claims.

The use of our product candidates in clinical trials and the sale of any products for which we obtain marketing approval exposes us to the risk of product liability claims. Product liability claims might be brought against us by consumers, healthcare providers, pharmaceutical companies or others selling or otherwise coming into contact with our products. There is a risk that our product candidates may induce adverse events. If we cannot successfully defend against product liability claims, we could incur substantial liability and costs. In addition, regardless of merit or eventual outcome, product liability claims may result in:

•the impairment of our business reputation;

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•the withdrawal of clinical trial participants;

•costs due to related litigation;

•the distraction of management’s attention from our primary business;

•substantial monetary awards to patients or other claimants;

•the inability to commercialize our product candidates; and

•decreased demand for our product candidates, if approved for commercial sale.

We believe our product liability insurance coverage is sufficient in light of our current commercial and clinical programs; however, we may not be able to maintain insurance coverage at a reasonable cost or in sufficient amounts to protect us against losses due to liability. We intend to expand our insurance coverage each time we commercialize an additional product; however, we may be unable to obtain product liability insurance on commercially reasonable terms or in adequate amounts. On occasion, large judgments have been awarded in class action lawsuits based on drugs or medical treatments that had unanticipated adverse effects. A successful product liability claim or series of claims brought against us could adversely affect our results of operations and business.

Patients with the diseases targeted by certain of our product candidates are often already in severe and advanced stages of disease and have both known and unknown significant pre-existing and potentially life-threatening health risks. During the course of treatment, patients may suffer adverse events, including death, for reasons that may be related to our product candidates. Such events could subject us to costly litigation, require us to pay substantial amounts of money to injured patients, delay, negatively impact or end our opportunity to receive or maintain regulatory approval to market our products, or require us to suspend or abandon our commercialization efforts. Even in a circumstance in which we do not believe that an adverse event is related to our products, the investigation into the circumstance may be time-consuming or inconclusive. These investigations may interrupt our sales efforts, delay our regulatory approval process in other countries, or impact and limit the type of regulatory approvals our product candidates receive or maintain. As a result of these factors, a product liability claim, even if successfully defended, could have a material adverse effect on our business, financial condition or results of operations.

Risks Related to Our Dependence on Third Parties

Our existing therapeutic collaborations are important to our business, and future collaborations may also be important to us. If we are unable to maintain any of these collaborations, or if these collaborations are not successful, our business could be adversely affected.

We have relatively limited capabilities for drug development and have limited experience of carrying out sales, marketing and distribution activities for KIMMTRAK. We have previously entered into collaborations with other companies that we believe can provide similar capabilities. These collaborations provided us with important funding for our development programs and technology platforms, and we could receive additional funding if we enter into further collaborations in the future. In addition, we have entered and may enter in the future into collaboration agreements whereby we investigate the therapeutic benefit of our own products or product candidates in combination with a product or product candidate of a third party. For example, in February 2024, we entered into a clinical trial collaboration and supply agreement with BMS, pursuant to which we will sponsor and fund the PRISM-MEL-301 clinical trial of our candidate brenetafusp + BMS’s nivolumab versus a control arm of either nivolumab or nivolumab + BMS’s relatlimab, depending on the country where the patient is enrolled, in first line advanced cutaneous melanoma, and BMS will provide nivolumab. Any future collaborations we enter into, may pose a number of risks, including the following:

•collaborators have significant discretion in determining the efforts and resources that they will apply to these collaborations;

•collaborators may not perform their obligations as expected;

•collaborators may not pursue development and commercialization of any product candidates that achieve regulatory approval or may elect not to continue or renew development or commercialization programs based on clinical trial results, changes in the collaborators’ strategic focus or available funding, or external factors, such as an acquisition, that divert resources or create competing priorities;

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•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;

•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; this may also happen if the collaborators’ development of competing products is substantially faster than our development timelines;

•collaborators may not further develop product candidates developed by us or co-developed with us under the collaboration;

•product candidates discovered in collaboration with us may be viewed by our collaborators as competitive with their own product candidates or products, which may cause collaborators to cease to devote resources to the commercialization of our product candidates;

•a collaborator with marketing and distribution rights to one or more of our product candidates that achieve regulatory approval may not commit sufficient resources to the marketing and distribution of such product or products;

•disagreements with collaborators, including disagreements over proprietary rights, contract interpretation or the preferred course of development, might cause delays or termination of the research, development or commercialization of product candidates, might lead to additional responsibilities for us with respect to product candidates, or might result in litigation or arbitration, any of which would be time-consuming and expensive;

•collaborators have certain defined rights to change or expand the scope of development programs during the course of the collaboration. This may lead to additional research work for us that may be time-consuming and expensive. Such work may compete with our own development programs and may delay timelines to market or proof-of-concept for our product candidates. If development programs under the collaboration turn out to be more costly and time-consuming, such unanticipated costs and work could likewise compete with our internal development programs;

•collaborators may not properly maintain, enforce or defend our intellectual property or proprietary information or may use them 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, misappropriate or otherwise violate the intellectual property or proprietary rights of third parties, which may expose us to litigation and potential liability, and collaborators may also allege that we are liable for potential infringement, misappropriation or other violations of third-party intellectual property or proprietary rights during the research and development work for the collaboration;

•certain collaborations may be terminated for the convenience of the collaborator and, if terminated, we could be required to raise additional capital to pursue further development or commercialization of the applicable product candidates. For example, certain of our collaboration and license agreements may be terminated for convenience upon the completion of a specified notice period; and

•collaborators may discontinue the development of product candidates within the collaboration, for example if they consider the results achieved so far for the product candidates not promising enough or if their development strategies change.

If our therapeutic collaborations do not result in the successful development and commercialization of products or if one of our collaborators terminates its agreement with us, we may not receive any future research funding or milestone or royalty payments under the collaboration, or we may not be able to complete combination trials. All of the risks relating to product development, regulatory approval and commercialization described in this Annual Report also apply to the activities of our program collaborators.

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Additionally, subject to its contractual obligations to us, if one of our collaborators is involved in other clinical trials or projects, such as a business combination, the collaborator might deemphasize or terminate the development or commercialization of any product candidate licensed to it by us. If one of our collaborators terminates its agreement with us, we may find it more difficult to attract new collaborators.

For some of our product candidates, we may in the future determine to collaborate with additional pharmaceutical and biotechnology companies for development and potential commercialization of therapeutic products. We face significant competition in seeking appropriate collaborators. Our ability to reach a definitive agreement for a collaboration will depend, among other things, upon our assessment of the collaborator’s resources and expertise, the terms and conditions of the proposed collaboration and the proposed collaborator’s evaluation of a number of factors. These factors may include the design or results of clinical trials, the likelihood of approval by the FDA or similar regulatory authorities outside the United States, the potential market for the subject product candidate, the costs and complexities of manufacturing and delivering such product candidate to patients, the potential of competing products, and the existence of uncertainty with respect to our ownership of technology, which can exist if there is a challenge to such ownership without regard to the merits of the challenge and industry and market conditions generally. The collaborator may also consider alternative product candidates or technologies for similar indications that may be available to collaborate on and whether such a collaboration could be more attractive than the one with us for our product candidate.

Collaborations are complex and time-consuming to negotiate and document. In addition, there have been a significant number of business combinations among large pharmaceutical companies that reduced the number of potential future collaborators. If we are unable to reach agreements with suitable collaborators on a timely basis, on acceptable terms, or at all, we may have to curtail the development of a product candidate, reduce or delay one or more of our other development programs, delay our potential commercialization or reduce the scope of any sales or marketing activities, or increase our expenditures and undertake development or commercialization activities at our own expense. If we elect to fund and undertake development or commercialization activities on our own, we may need to obtain additional expertise and additional capital, which may not be available to us on acceptable terms or at all. If we fail to enter into collaborations and do not have sufficient funds or expertise to undertake the necessary development and commercialization activities, we may not be able to further develop our product candidates or bring them to market or continue to develop our technology platforms and our business may be materially and adversely affected.

We may also be restricted under existing collaboration agreements from entering into future agreements on certain terms with potential collaborators. Subject to certain specified exceptions, each of our existing therapeutic collaborations contains an exclusivity restriction on our engaging in activities that are the subject of the collaboration with third parties for specified periods of time.

We rely on CROs and other third parties to conduct our clinical trials and expect to rely on CROs and other third parties to conduct future clinical trials, as well as investigator-sponsored clinical trials of our product candidates. If these CROs and other third parties do not successfully carry out their contractual duties, comply with regulatory requirements or meet expected deadlines, we may not be able to obtain regulatory approval for or commercialize our product candidates and our business could be substantially harmed.

We rely and expect to continue to rely on CROs, medical institutions, clinical investigators, contract laboratories and other third parties to conduct or otherwise support clinical trials for our product candidates, including our TEBE-AM Phase 3 advanced melanoma tebentafusp trial, our EORTC-sponsored ATOM Phase 3 trial of KIMMTRAK in adjuvant uveal (ocular) melanoma, our PRISM-MEL-301 Phase 3 clinical trial of brenetafusp in first line advanced cutaneous melanoma, our Phase 1/2 clinical trial of brenetafusp in multiple solid tumors, our Phase 1/2 clinical trial of IMC-M113V in people who live with HIV, and our Phase 1 trial with IMC-R117C in colorectal cancer. We may also rely on academic and private non-academic institutions to conduct and sponsor clinical trials relating to our product candidates. We will not control the design or conduct of the investigator-sponsored trials, and it is possible that the FDA or non-U.S. regulatory authorities will not view these investigator-sponsored trials as providing adequate support for future clinical trials, whether controlled by us or third parties, for any one or more reasons, including elements of the design or execution of the trials or safety concerns or other trial results.

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Such arrangements will likely provide us certain information rights with respect to the investigator-sponsored trials, including access to and the ability to use and reference the data, including for our own regulatory filings, resulting from the investigator-sponsored trials. However, we would not have control over the timing and reporting of the data from investigator-sponsored trials, nor would we own the data from the investigator-sponsored trials. If we are unable to confirm or replicate the results from the investigator-sponsored trials or if negative results are obtained, we would likely be further delayed or prevented from advancing further clinical development of our product candidates. Further, if investigators or institutions breach their obligations with respect to the clinical development of our product candidates, or if the data proves to be inadequate compared to the first-hand knowledge we might have gained had the investigator-sponsored trials been sponsored and conducted by us, then our ability to design and conduct any future clinical trials ourselves may be adversely affected.

We rely and expect to continue to rely heavily on CROs, medical institutions, clinical investigators, contract laboratories and other third parties for execution of clinical trials for our product candidates and control only certain aspects of their activities. Nevertheless, we are responsible for ensuring that each of our clinical trials is conducted in accordance with the applicable protocol, legal and regulatory requirements and scientific standards, and our reliance on CROs will not relieve us of our regulatory responsibilities. For any violations of laws and regulations during the conduct of our clinical trials, we could be subject to warning letters or enforcement action that may include civil penalties up to and including criminal prosecution.

We, our principal investigators and our CROs are required to comply with regulations, including Good Clinical Practices ("GCPs"), for conducting, monitoring, recording and reporting the results of clinical trials to ensure that the data and results are scientifically credible and accurate, and that the trial patients are adequately informed of the potential risks of participating in clinical trials and their rights are protected. These regulations are enforced by the FDA, the Competent Authorities of the EEA countries and comparable foreign regulatory authorities for any products in clinical development. The FDA enforces GCP regulations through periodic inspections of clinical trial sponsors, principal investigators and trial sites. If we, our principal investigators or our CROs fail to comply with applicable GCPs, the clinical data generated in our clinical trials may be deemed unreliable and the FDA or comparable foreign regulatory authorities may require us to perform additional clinical trials before approving our marketing applications. We cannot assure you that, upon inspection, the FDA will determine that any of our future clinical trials will comply with GCPs. In addition, our clinical trials must be conducted with product candidates produced under cGMP regulations. Our failure or the failure of our principal investigators or CROs to comply with these regulations may require us to repeat clinical trials, which would delay the regulatory approval process and could also subject us to enforcement action. We also are required to register ongoing clinical trials and post the results of completed clinical trials on a government-sponsored database, ClinicalTrials.gov, within certain timeframes. Failure to do so can result in fines, adverse publicity and civil and criminal sanctions.

We expect that CROs will conduct all of our clinical trials. As a result, many important aspects of our development programs, including their conduct and timing, are outside of our direct control. Our reliance on third parties to conduct future clinical trials also results in less direct control over the management of data developed through clinical trials than would be the case if we were relying entirely upon our own staff. Communicating with outside parties can also be challenging, potentially leading to mistakes as well as difficulties in coordinating activities. Outside parties may:

•have staffing difficulties;

•fail to comply with contractual obligations;

•experience regulatory compliance issues;

•undergo changes in priorities or become financially distressed; or

•form relationships with other entities, some of which may be our competitors.

These factors may materially adversely affect the willingness or ability of third parties to conduct our clinical trials and may subject us to unexpected cost increases that are beyond our control. If the principal investigators or CROs do not perform clinical trials in a satisfactory manner, breach their obligations to us or fail to comply with regulatory requirements, the development, regulatory approval and commercialization of our product candidates may be delayed, we may not be able to obtain regulatory approval and commercialize our product candidates, or our development program materially and irreversibly harmed. If we are unable to rely on clinical data collected by our principal investigators or CROs, we could be required to repeat, extend the duration of, or increase the size of any clinical trials we conduct, and this could significantly delay commercialization and require significantly greater expenditures.

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In addition, in 2023, we signed an agreement for an EORTC-sponsored trial to study KIMMTRAK as adjuvant therapy for uveal (or ocular) melanoma (ATOM) in HLA-A*02:01 positive patients, for which the first patient was randomized in December 2024. While the Phase 3 trial is conducted by EORTC and we have limited ability to control the trial or steer EORTC’s activities, our ability to expand KIMMTRAK into adjuvant uveal (or ocular) melanoma depends in great part on the outcome of that trial. If EORTC does not conduct the trial in a satisfactory manner or fails to comply with regulatory requirements, we may be required to repeat the Phase 3 trial in order to get regulatory approval to expand KIMMTRAK into adjuvant uveal (or ocular) melanoma, which would significantly delay commercialization and require significantly greater expenditures from us.

If any of our relationships with these third-party principal investigators or CROs terminate, we may not be able to enter into arrangements with alternative CROs on commercially reasonable terms, or at all. If principal investigators or CROs do not successfully carry out their contractual duties or obligations or meet expected deadlines, if they need to be replaced or if the quality or accuracy of the clinical data they obtain is compromised due to the failure to adhere to our clinical protocols, regulatory requirements or for other reasons, any clinical trials such principal investigators or CROs are associated with may be extended, delayed or terminated, and we may not be able to obtain regulatory approval for or successfully commercialize our product candidates. As a result, we believe that our financial results and the commercial prospects for our product candidates in the subject indication would be harmed, our costs could increase and our ability to generate revenue could be delayed.

We contract with third parties for the manufacture of our product candidates for pre-clinical development, clinical testing, and commercial supply. This reliance on third parties increases the risk that we will not have sufficient quantities of our product candidates or products or such quantities at an acceptable cost, which could delay, prevent or impair our development or commercialization efforts.

We do not currently own or operate, nor do we currently have any plans to establish, any manufacturing facilities or personnel. We rely, and expect to continue to rely, on third parties for the manufacture of our product candidates for pre-clinical development and clinical testing, and the commercial manufacture of our products. This reliance on third parties increases the risk that we will not have sufficient quantities of our product candidates or products or such quantities at an acceptable cost or quality, which could delay, prevent or impair our development or commercialization efforts.

The facilities used by our contract manufacturers to manufacture our product candidates must be inspected by the FDA or comparable foreign regulatory authorities pursuant to pre-approval inspections that will be conducted after we submit our marketing applications to the FDA or comparable foreign regulatory authorities. We have limited control over the manufacturing process of, and will be completely dependent on, our contract manufacturers for compliance with cGMPs in connection with the manufacture of our product candidates. If our contract manufacturers cannot successfully manufacture material that conforms to our specifications and the strict regulatory requirements of the FDA or others, they will not be able to pass regulatory inspections and/or maintain regulatory compliance for their manufacturing facilities. In addition, we have limited control over the ability of our contract manufacturers to maintain adequate quality control, quality assurance and qualified personnel. If the FDA or a comparable foreign regulatory authority finds deficiencies with or does not approve these facilities for the manufacture of our product candidates or if it finds deficiencies or withdraws any such approval in the future, we may need to find alternative manufacturing facilities, which would significantly impact our ability to develop, obtain regulatory approval for or market our product candidates, if approved. We, or our contract manufacturers, any future collaborators and their contract manufacturers could be subject to periodic unannounced inspections by the FDA, competent authorities of Member States or other comparable foreign regulatory authorities, to monitor and ensure compliance with cGMP. Despite our efforts to audit and verify regulatory compliance, one or more of our third-party manufacturing vendors may be found on regulatory inspection by the FDA, competent authorities of Member States or other comparable foreign regulatory authorities to be noncompliant with cGMP regulations. Further, our failure, or the failure of our third-party manufacturers, to comply with applicable regulations could result in sanctions being imposed on us, including shutdown of the third-party vendor or invalidation of drug product lots or processes, clinical holds, fines, injunctions, civil penalties, delays, suspension, variation or withdrawal of approvals, license revocation, seizures or recalls of product candidates or products, if approved, operating restrictions and criminal prosecutions, any of which could significantly and adversely affect our business and supplies of our product candidates.

We may be unable to establish any agreements with third-party manufacturers or to do so on acceptable terms. Even if we are able to establish agreements with third-party manufacturers, reliance on third -party manufacturers entails additional risks, including:

•reliance on the third party for regulatory compliance and quality assurance;

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•the possible breach of the manufacturing agreement by the third party;

•the possible misappropriation or unauthorized disclosure of our proprietary information, including our trade secrets and know-how; and

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

Our product candidates and any products that we may develop may compete with other product candidates and approved products for access to manufacturing facilities. There are a limited number of manufacturers that operate under cGMP regulations and that might be capable of manufacturing for us.

Any performance failure on the part of our existing or future manufacturers could delay clinical development or marketing approval. If our current contract manufacturers cannot perform as agreed, we may be required to replace such manufacturers. We may incur added costs and delays in identifying and qualifying any such replacement.

In addition, in February 2024, we entered in a clinical trial collaboration and supply agreement with BMS pursuant to which we will sponsor and fund the PRISM-MEL-301 clinical trial of brenetafusp in combination with nivolumab, and BMS will provide nivolumab. The risks related to our reliance on BMS for clinical supply of nivolumab is similar to the risks related to our reliance on contract manufacturers for clinical supply of our product candidates.

Our current and anticipated future dependence upon others for the manufacture of our product candidates or products may adversely affect our future profit margins and our ability to commercialize any products that receive marketing approval on a timely and competitive basis.

The third parties upon whom we rely for the supply of the active pharmaceutical ingredient used in our product candidates are our sole source of supply, and the loss of any of these suppliers could significantly harm our business.

The active pharmaceutical ingredients ("API") used in our product candidates are supplied to us from single-source suppliers. Our ability to successfully develop our product candidates, and to ultimately supply our commercial products in quantities sufficient to meet the market demand, depends in part on our ability to obtain the API for these products in accordance with regulatory requirements and in sufficient quantities for clinical testing and commercialization. We do not currently have arrangements in place for a redundant or second-source supply of any such API in the event any of our current suppliers of such API cease their operations for any reason. We are also unable to predict how changing global and macroeconomic conditions such as public health crises, the war in Ukraine, the conflict in the Middle East (such as the potential impact on our international operations because our distributor outside the US and Western Europe has significant exposure in the region), global geopolitical tension and changes in inflation will affect our third- party suppliers and manufacturers. Any negative impact of such matters on our third-party suppliers and manufacturers may also have an adverse impact on our results of operations or financial condition.

For all of our product candidates, we intend to identify and qualify additional manufacturers to provide such API prior to submission of a BLA to the FDA and/or an MAA to the EMA. We are not certain, however, that our single-source suppliers will be able to meet our demand for their products, either because of the nature of our agreements with those suppliers, our limited experience with those suppliers or our relative importance as a customer to those suppliers. It may be difficult for us to assess their ability to timely meet our demand in the future based on past performance. While our suppliers have generally met our demand for their products on a timely basis in the past, they may subordinate our needs in the future to their other customers.

Establishing additional or replacement suppliers for the API used in our product candidates, if required, may not be accomplished quickly. If we are able to find a replacement supplier, such replacement supplier would need to be qualified and may require additional regulatory inspection or approval, which could result in further delay. While we seek to maintain adequate inventory of the API used in our product candidates, any interruption or delay in the supply of components or materials, or our inability to obtain such API from alternate sources at acceptable prices in a timely manner could impede, delay, limit or prevent our development efforts, which could harm our business, results of operations, financial condition and prospects.

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We may seek to establish additional collaborations, and, if we are not able to establish them on commercially reasonable terms, or at all, we may have to alter our development and commercialization plans.

Our product development programs and the potential commercialization of our product candidates will require substantial additional cash to fund expenses. For some of our product candidates, we may decide to collaborate with additional pharmaceutical and biotechnology companies for the development and potential commercialization of those product candidates.

We face significant competition in seeking appropriate collaborators. Whether we reach a definitive agreement for a collaboration will depend, among other things, upon our assessment of the collaborator’s resources and expertise, the terms and conditions of the proposed collaboration and the proposed collaborator’s evaluation of a number of factors. Those factors may include the design or results of clinical trials, the likelihood of approval by the FDA or similar regulatory authorities outside the United States, the potential market for the subject product candidate, the costs and complexities of manufacturing and delivering such product candidate to patients, the potential of competing products, the existence of uncertainty with respect to our ownership of technology, which can exist if there is a challenge to such ownership without regard to the merits of the challenge and industry and market conditions generally. The collaborator may also consider alternative product candidates or technologies for similar indications that may be available to collaborate on and whether such a collaboration could be more attractive than the one with us for our product candidate. The terms of any additional collaborations or other arrangements that we may establish may not be favorable to us.

We may also be restricted under collaboration agreements from entering into future agreements on certain terms with other potential collaborators. Collaborations are complex and time- consuming to negotiate and document. In addition, there have been a significant number of recent business combinations among large pharmaceutical companies that have resulted in a reduced number of potential future collaborators.

We may not be able to negotiate additional collaborations on a timely basis, on acceptable terms, or at all. If we are unable to do so, we may have to curtail the development of the product candidate for which we are seeking to collaborate, reduce or delay its development program or one or more of our other development programs, delay its potential commercialization or reduce the scope of any sales or marketing activities, or increase our expenditures and undertake development or commercialization activities at our own expense. If we elect to increase our expenditures to fund development or commercialization activities on our own, we may need to obtain additional capital, which may not be available to us on acceptable terms or at all. If we do not have sufficient funds, we may not be able to further develop our product candidates or bring them to market and generate revenue.

In addition, any future collaborations that we enter into may not be successful. The success of our collaboration arrangements will depend heavily on the efforts and activities of our collaborators. Collaborators generally have significant discretion in determining the efforts and resources that they will apply to these collaborations. Disagreements between parties to a collaboration arrangement regarding clinical development and commercialization matters can lead to delays in the development process or commercializing the applicable product candidate and, in some cases, termination of the collaboration arrangement. These disagreements can be difficult to resolve if neither of the parties has final decision-making authority. Collaborations with pharmaceutical or biotechnology companies and other third parties often are terminated or allowed to expire by the other party. Any such termination or expiration would adversely affect us financially and could harm our business reputation.

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Where we license technology from a third party, the prosecution, maintenance, enforcement and defense of the patent or other intellectual property or proprietary rights licensed from such third party may be controlled by the third party, which may impact the scope of patent or other protection.

IMCR US Equity

IMCR · 10-K · period ended 2025-12-31

Item 1A. Risk Factors

IMCR US Equity☆

IMCR · 10-K · period ended 2025-12-31

Item 1A. Risk Factors

IMCR US Equity