Enliven Therapeutics (ELVN) Risk Analysis

Where possible, we plan to seek Breakthrough Therapy designation for one or more of our current or future product candidates. A breakthrough therapy is defined as a drug or biologic that is intended, alone or in combination with one or more other drugs or biologics, to treat a serious or life-threatening disease or condition and preliminary clinical evidence indicates that the drug or biologic may demonstrate substantial improvement over existing therapies on one or more clinically significant endpoints, such as substantial treatment effects observed early in clinical development. For product candidates that have been designated as breakthrough therapies, interaction and communication between the FDA and the sponsor of the trial can help to identify the most efficient path for clinical development while minimizing the number of patients placed in ineffective control regimens. Drugs designated as breakthrough therapies by the FDA may also be eligible for other expedited approval programs, including accelerated approval. Designation as a breakthrough therapy is within the discretion of the FDA. Accordingly, even if we believe one of our product candidates meets the criteria for designation as a breakthrough therapy, the FDA may disagree and instead determine not to make such designation. In any event, the receipt of a Breakthrough Therapy designation for a product candidate may not result in a faster development process, review or approval compared to candidate products considered for approval under non-expedited FDA review procedures and does not assure ultimate approval by the FDA. In addition, even if one or more of our product candidates qualify as breakthrough therapies, the FDA may later decide that the product no longer meets the conditions for qualification. Thus, even though we may seek Breakthrough Therapy designation for one or more of our current or future product candidates, there can be no assurance that it will receive Breakthrough Therapy designation.

We have never commercialized a product candidate as a company. We may license certain rights with respect to our product candidates to collaborators, and, if so, we will rely on the assistance and guidance of those collaborators. For product candidates for which we retain commercialization rights and marketing approval, we will have to develop our own sales, marketing and supply organization or outsource these activities to a third party. Factors that may affect our ability to commercialize our product candidates, if approved, on our own include recruiting and retaining adequate numbers of effective sales and marketing personnel, developing adequate educational and marketing programs to increase public acceptance of our approved product candidates, ensuring regulatory compliance of our company, employees and third parties under applicable healthcare laws, and other unforeseen costs associated with creating an independent sales and marketing organization. Developing a sales and marketing organization will be expensive and time-consuming and could delay the launch of our product candidates upon approval. We may not be able to build an effective sales and marketing organization. If we are unable to build our own distribution and marketing capabilities or to find suitable partners for the commercialization of our product candidates, we may not generate revenues from them or be able to reach or sustain profitability.

As part of our development strategy, we are seeking strategic collaborations to develop our current or future product candidates in combination with one or more currently approved cancer therapies or therapies in development. We plan to complete our exploratory evaluation of ELVN-002 in combination with Herceptin, Kadcyla, and Enhertu in patients with HER2+ solid tumors in the second half of 2025. To prioritize the advancement of ELVN-001 and its upcoming pivotal trial, we are exploring strategic alternatives for the ELVN-002 program, and we do not intend to pursue its development beyond 2025. Even if any of our current or future product candidates were to receive marketing approval or be commercialized for use in combination with other existing therapies, we would continue to be subject to the risks that the FDA, EMA or other comparable foreign regulatory authorities could revoke approval of the therapy used in combination with any of our product candidates, or safety, efficacy, manufacturing or supply issues could arise with these existing therapies. In addition, it is possible that existing therapies with which our product candidates are approved for use could themselves fall out of favor or be relegated to later lines of treatment. This could result in the need to identify other combination therapies for our product candidates or our own products being removed from the market or being less successful commercially. We or our future third party collaborators may also evaluate our current or future product candidates in combination with one or more other cancer therapies that have not yet been approved for marketing by the FDA, EMA or comparable foreign regulatory authorities. We will not be able to market and sell any product candidate in combination with any such unapproved cancer therapies that do not ultimately obtain marketing approval. If the FDA, EMA or other comparable foreign regulatory authorities do not approve or withdraw their approval of these other therapies, or if safety, efficacy, commercial adoption, manufacturing or supply issues arise with the therapies we choose to evaluate in combination with any of our current or future product candidates, we may be unable to obtain approval of or successfully market any one or all of the current or future product candidates we develop. Additionally, if the third-party providers of therapies or therapies in development used in combination with our current or future product candidates are unable to produce sufficient quantities for clinical trials or for commercialization of our current or future product candidates, or if the cost of combination therapies are prohibitive, our development and commercialization efforts would be impaired, which would have an adverse effect on our business, financial condition, results of operations and growth prospects. Further, under the new leadership at the HHS under the current administration, agency reorganization, mass layoffs due to the reduction in force initiative and other measures implemented by the Department of Government Efficiency may impact the normal operations of the FDA as well as other federal agencies. FDA may lack adequate staff and resources to meet current review, approval, and inspection schedules, which could delay our anticipated timelines. In January 2025, an executive order entitled "Unleashing Prosperity Through Deregulation", was issued which calls for at least 10 existing regulations to be repealed whenever an executive department or agency publicly proposes for notice and comment or otherwise promulgates a new regulation. Recent developments at the FDA include implementation of Elsa, a generative AI tool, across all centers at the agency, announcement of a plan to phase out animal testing for monoclonal antibodies and certain other drugs, and the announcement of a new Commissioner's National Priority Voucher ("CNPV") program to companies supporting certain U.S. national health priorities and interests. FDA has also increased its scrutiny of foreign drug manufacturing facilities and other contractors based in China, especially with respect to the transfer of biological materials, genetic data, and other sensitive data of American patients to parties located in China. FDA's "real-time" release of newly issued Complete Response Letters ("CRLs") associated with withdrawn or abandoned applications, if applicable to any of our product candidates, can materially impact our competitive advantage and intellectual property. It is unclear how our industry and our clinical programs will be impacted by policies and regulations implemented under the current administration and FDA commissioner, or other executive orders. There is significant uncertainty in the industry and how federal agencies like the FDA will change in the coming years under the current administration. To the extent the agency reorganization and other agency changes lead to disruptions in FDA's operations, our correspondence and regulatory review processes with the FDA may be materially delayed.

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 to such trials' conclusion as required by the FDA, EMA or other comparable foreign regulatory authorities. Patient enrollment is a significant factor in the timing of clinical trials. Our ability to enroll eligible patients may be limited, and we have experienced minor delays in enrollment. Because there are effective, approved drugs and/or ongoing clinical trials being conducted for CML, it may make it difficult for us to enroll patients in our trials for the same indications. For example, CML patient enrollment could have been and will likely be affected by the approval of Scemblix (asciminib) as well as our competitors that have ongoing clinical trials for programs that are under development for the same indications as our product candidates because patients who would otherwise be eligible for our clinical trials instead enroll in clinical trials of our competitors' programs. Additionally, the CML patient population is relatively small and certain clinical trials for future product candidates may be focused on indications with relatively small patient populations, which may further limit enrollment of eligible patients or may result in slower enrollment than we anticipate. For each of our programs, we cannot be certain that the number of patients enrolled in each program will suffice for regulatory approval. If our strategies for patient identification and enrollment prove unsuccessful, we may have difficulty enrolling or maintaining patients appropriate for our product candidates. Patient enrollment for our current or any future clinical trials has been and may continue to be affected by other factors, including: - size and nature of the patient population;- severity of the disease under investigation;- availability and efficacy of approved drugs for the disease under investigation;- patient eligibility criteria for the trial in question as defined in the protocol, including biomarker-driven identification and/or certain highly specific criteria related to stage of disease progression, which may limit the patient populations eligible for our clinical trials to a greater extent than competing clinical trials for the same indication that do not have biomarker-driven patient eligibility criteria;- perceived risks and benefits of the product candidate under study;- clinicians' and patients' perceptions as to the potential advantages of the product candidate being studied in relation to other available therapies, including any new products that may be approved or other product candidates being investigated for the indications we are investigating;- clinicians' willingness to screen their patients for biomarkers to indicate which patients may be eligible for enrollment in our clinical trials;- patient referral practices of physicians;- the ability to monitor patients adequately during and after treatment;- treatment of patients at local facilities rather than central facilities;- proximity and availability of clinical trial sites for prospective patients;- policies and regulations or other executive orders related to clinical trials in foreign countries; and - the risk that patients enrolled in clinical trials will drop out of the trials before completion or, because they may be late-stage cancer patients, will not survive the full terms of the clinical trials. Our inability to enroll a sufficient number of patients for our clinical trials would result in significant delays or may require us to abandon one or more clinical trials altogether. We have established clinical trial sites in Israel, which may face enrollment, retention, operational or other difficulties due to conflicts within the region, including, for example, difficulties importing clinical trial drug through Israeli customs, difficulties with patient enrollment, or difficulties with patients or medical personnel accessing appropriate medical facilities. Enrollment delays in our clinical trials may result in increased development costs for our product candidates and jeopardize our ability to obtain marketing approval for the sale of our product candidates. Furthermore, even if we are able to enroll a sufficient number of patients for our clinical trials, we may have difficulty maintaining participation in our clinical trials through the treatment and any follow-up periods.

From time to time, we have publicly disclosed and may publicly disclose additional preliminary, interim or topline data from our preclinical studies and clinical trials. These interim updates are based on a preliminary analysis of then-available data, and the results and related findings and conclusions are subject to change following a more comprehensive review of the data related to the particular study or trial. For example, we may report responses in certain patients that are unconfirmed at the time and which do not ultimately result in confirmed responses to treatment after follow-up evaluations. We also make assumptions, estimations, calculations and conclusions as part of our analyses of data, and we may not have received or had the opportunity to fully and carefully evaluate all data. As a result, the topline results that we report may differ from future results of the same studies or trials, or different conclusions or considerations may qualify such results, once additional data have been received and fully evaluated. Topline 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, topline data should be viewed with caution until the final data are available. In addition, we may report interim analyses of only certain endpoints rather than all endpoints. 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. Adverse changes between interim data and final data could significantly harm our business and prospects. Further, additional disclosure of interim data by us or by our competitors in the future could result in volatility in the price of our common stock. In addition, the information we choose to publicly disclose regarding a particular study or trial is typically selected from a more extensive amount of available information. Investors may not agree with what we determine is the material or otherwise appropriate information to include in our disclosure, and any information we determine not to disclose may ultimately be deemed significant with respect to future decisions, conclusions, views, activities or otherwise regarding a particular product candidate or our business. If the preliminary or topline data that we report differ from late, final or actual results, or if others, including regulatory authorities, disagree with the conclusions reached, our ability to obtain approval for, and commercialize, any of our product candidates may be harmed, which could harm our business, financial condition, results of operations and prospects.

Before we can initiate clinical trials of a product candidate in any indication, we must submit the results of preclinical studies to the FDA, EMA or other comparable foreign regulatory authorities along with other information, including information about the product candidate's chemistry, manufacturing and controls and our proposed clinical trial protocol, as part of an IND or similar regulatory submission under which we must receive authorization to proceed with clinical development. Although we have received clearance of the IND for ELVN-001, the FDA, EMA or other comparable foreign regulatory authorities have required, and may in the future require, us to conduct additional studies before they allow us to initiate additional clinical trials or at any time during clinical testing, clinical trial authorization or comparable application, which may lead to additional delays and increase the costs of our preclinical development programs. Further, changes in regulations in the United States and other countries may increase our compliance costs, make it more difficult to conduct trials in some countries or to implement global trials, or result in changes to our current clinical plans and timelines. Before obtaining marketing approval from the FDA of ELVN-001 or any other programs, we must conduct extensive clinical trials to demonstrate safety and efficacy. Clinical testing is expensive, time consuming and uncertain as to outcome. In addition, we expect to rely in part on preclinical, clinical and quality data generated by our CROs and other third parties for regulatory submissions for our product candidates. While we have or will have agreements governing these third parties' services, we have limited influence over their actual performance. We could encounter delays because we may need to relocate our corporate headquarters, which includes office and laboratory space. If these third parties do not make data available to us, or, if applicable, make regulatory submissions in a timely manner, in each case pursuant to our agreements with them, our development programs may be significantly delayed and we may need to conduct additional studies or collect additional data independently. In either case, our development costs would increase. We may not be able to file INDs for future product candidates on the timelines we expect. For example, we may experience manufacturing delays or other delays with IND enabling studies. Moreover, we cannot be sure that submission of an IND will result in the FDA allowing clinical trials to begin, or that, once begun, issues will not arise that suspend or terminate clinical trials. Additionally, even if the FDA agrees with the design and implementation of the clinical trials set forth in an IND, we cannot guarantee that it will not change its requirements in the future. These considerations also apply to new clinical trials we may submit as amendments to existing INDs or to a new IND. Any failure to file INDs on the timelines we expect or to obtain regulatory approvals for our planned clinical trials may prevent us from initiating or completing our clinical trials or commercializing our product candidates on a timely basis, if at all. We could also encounter delays if a clinical trial is suspended or terminated by us, by the IRBs or independent ethics committees of the institutions in which such trials are being conducted, by a Data Safety Monitoring Board for such trial or by the FDA or foreign regulatory authorities. Such authorities may impose such a suspension or termination 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 foreign regulatory authorities resulting in the imposition of a clinical hold, unforeseen safety issues or adverse events, failure to demonstrate a benefit from using a pharmaceutical, changes in governmental regulations or administrative actions or lack of adequate funding to continue the clinical trial. In addition, changes in regulatory requirements and policies may occur, and we may need to amend clinical trial protocols to comply with these changes. For example, the Clinical Trials Regulation EU No 536/2014 entered into application on January 31, 2022, which aims to harmonize and streamline clinical trial authorization, simplify adverse event reporting procedures, and increase clinical trial transparency. Changes to regulatory requirements or the implementation of new requirements can increase the costs of compliance and expose us to great liabilities. Amendments may require us to resubmit our clinical trial protocols to IRBs or ethics committees for reexamination, which may impact the costs, timing or successful completion of a clinical trial. Certain of our investigators are also scientific advisors or consultants who receive compensation from us. Under certain circumstances, we may be required to report some of these relationships to the FDA. Although we expect any such relationships to be within the FDA's guidelines, the FDA 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 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 and may ultimately lead to the denial of marketing approval of our product candidates. If we experience delays in the completion of, or termination of, any clinical trial of any product candidate, the commercial prospects of such product candidate will be harmed, and our ability to generate product revenues will be delayed. Moreover, any delays in completing our clinical trials will increase our costs, slow down our development and approval process and jeopardize our ability to commence product sales and generate revenues which may harm our business, financial condition, results of operations and prospects significantly.

The design and implementation of clinical trials is a complex process. We have limited experience as a company in designing and conducting clinical trials. We are currently evaluating ELVN-001 in a Phase 1 clinical trial in adults with CML, and we are evaluating ELVN-002 in Phase 1 clinical trials in adults with solid tumors with HER2 alterations. We plan to complete our exploratory evaluation of ELVN-002 in combination with Herceptin, Kadcyla, and Enhertu in patients with HER2+ solid tumors in the second half of 2025. To prioritize the advancement of ELVN-001 and its upcoming pivotal trial, we are exploring strategic alternatives for the ELVN-002 program, and we do not intend to pursue its development beyond 2025. However, we have not initiated clinical trials for any other product candidate and we may experience unexpected or adverse results in the future. In part because of this lack of experience as a company and our limited infrastructure, we cannot be certain that our ongoing and planned preclinical studies and clinical trials will be completed on time, that we will successfully or cost-effectively design and implement clinical trials that achieve the desired clinical endpoints efficiently, or at all. Large-scale clinical trials would require significant additional financial and management resources and reliance on CROs and consultants. Relying on third-party clinical investigators, CROs and consultants may force us to encounter delays that are outside of our control. We may be unable to identify and contract with sufficient investigators, CROs and consultants on a timely basis or at all. There can be no assurance that we will be able to negotiate and enter into any necessary services agreement with CROs on terms that are acceptable to it on a timely basis or at all.

Our prospects depend in large part upon developing and commercializing and/or otherwise licensing ELVN-001 and discovering, developing and commercializing product candidates from our other research programs, and failure to successfully identify, develop and commercialize additional product candidates could impair our ability to grow. Our future operating results are dependent on our ability to successfully discover, develop, obtain regulatory approval for and commercialize product candidates including ELVN-001 and product candidates from our research programs, including the development of any combination drug products or companion diagnostics, or entering into, on favorable terms, any collaboration, licensing or other arrangements that may be necessary or desirable to develop or commercialize our product candidates. To prioritize the advancement of ELVN-001 and its upcoming pivotal trial, we are exploring strategic alternatives for the ELVN-002 program and we do not intend to pursue its development beyond 2025. A product candidate can unexpectedly fail at any stage of development. The historical failure rate for product candidates is high due to risks relating to safety, efficacy, clinical execution, changing standards of medical care and other unpredictable variables. The results from preclinical testing or early clinical trials of a product candidate may not be predictive of the results that will be obtained in later stage clinical trials of the product candidate. The success of ELVN-001 and other product candidates we may develop will depend on many factors, including the following: - successful and timely initiation and completion of preclinical studies and clinical trials, including generating sufficient data to support the initiation or continuation of preclinical studies and clinical trials, including data that demonstrates improved efficacy, safety, and patient convenience compared to our competitors' products;- successful development of combination drug products;- successful development of a companion diagnostic, if required for regulatory approval of any product;- obtaining institutional review board ("IRB") approval at each clinical trial site;- approval of INDs for our planned clinical trials and future clinical trials;- the timely manufacture of sufficient quantities of a product candidate for use in clinical trials;- successful and timely patient selection and enrollment in and completion of clinical trials;- maintaining and establishing relationships with CROs, CMOs and clinical sites for the clinical development of our product candidates both in the United States and internationally, including in Europe, China and in other countries in the future;- the frequency and severity of adverse events in clinical trials;- demonstrating efficacy, safety and tolerability profiles that are satisfactory to the FDA, EMA or any comparable foreign regulatory authority for marketing approval;- the timely receipt of marketing approvals from applicable regulatory authorities;- the extent of any required post-marketing approval commitments to applicable regulatory authorities;- the maintenance of existing or the establishment of new supply arrangements with third-party drug product suppliers and manufacturers for clinical development, combination studies, and, if approved, commercialization of our product candidates;- obtaining and maintaining patent protection, trade secret protection and regulatory exclusivity, both in the United States and internationally;- the protection of our rights in our intellectual property portfolio;- the successful launch of commercial sales following any marketing approval;- a continued acceptable safety profile following any marketing approval;- commercial acceptance by patients, the medical community and third-party payors; and - our ability to compete with other therapies. We do not have complete control over many of these factors, including certain aspects of preclinical and clinical development and the regulatory submission process, potential threats to our intellectual property rights and the manufacturing, marketing, distribution and sales efforts of any future collaborator. If we are not successful with respect to one or more of these factors in a timely manner or at all, we could experience significant delays or an inability to successfully commercialize any product candidates from ELVN-001, which would materially harm our business. If we do not receive marketing approvals for such product candidates, we may not be able to continue our operations. Although a substantial amount of our efforts will focus on the continued preclinical and clinical testing and potential approval of our product candidates in our current pipeline, we expect to continue to innovate and potentially expand our portfolio. Research programs to identify product candidates may require substantial additional technical, financial and human resources, whether or not any new potential product candidates are ultimately identified. Our success may depend in part upon our ability to identify, select and develop promising product candidates and therapeutics. We may expend resources and ultimately fail to discover and generate additional product candidates suitable for further development. Even if we successfully advance any product candidates into preclinical and clinical development, their success will be subject to all of the preclinical, clinical, regulatory and commercial risks described elsewhere in this section. All product candidates are prone to risks of failure typical of biotechnology product development, including the possibility that a product candidate may not be suitable for clinical development as a result of its harmful side effects, limited efficacy or other characteristics indicating that it is unlikely to receive approval by the FDA, the EMA and other comparable foreign regulatory authorities and achieve market acceptance. If we do not successfully develop, commercialize and/or license ELVN-001, or if we do not successfully identify, develop and commercialize new product candidates, our business, prospects, financial condition and results of operations could be adversely affected.

We are currently focusing our resources and efforts on ELVN-001 and advancing our other research programs. We also plan to complete our exploratory evaluation of ELVN-002 in combination with Herceptin, Kadcyla, and Enhertu in patients with HER2+ solid tumors in the second half of 2025. To prioritize the advancement of ELVN-001 and its upcoming pivotal trial, we are exploring strategic alternatives for the ELVN-002 program, and we do not intend to pursue its development beyond 2025. Because we have limited financial and managerial resources, we must focus on a limited number of research programs and product candidates and on specific indications. As a result, we may forgo or delay pursuit of opportunities for other indications or with other product candidates that may have greater commercial potential. Our resource allocation decisions may cause us to fail to capitalize on viable commercial products or profitable market opportunities. Our spending on current and future research and development activities for ELVN-001, ELVN-002 and our other research programs, including the development of any combination drug products or companion diagnostics, may not yield any commercially viable products. If we do not accurately evaluate the commercial potential or target markets for ELVN-001, ELVN-002 and our other research programs, or the product candidates we are currently developing in these programs, we may relinquish valuable rights to our product candidates or programs through collaborations, licensing or other strategic arrangements in cases in which it would have been more advantageous for us to retain sole development and commercialization rights to such product candidate or program.

We are very early in our development efforts. We are currently evaluating ELVN-001 in a Phase 1 clinical trial in adults with CML, and we are evaluating ELVN-002 in Phase 1 clinical trials in adults with solid tumors with HER2 alterations. We also plan to complete our exploratory evaluation of ELVN-002 in combination with Herceptin, Kadcyla, and Enhertu in patients with HER2+ solid tumors in the second half of 2025. To prioritize the advancement of ELVN-001 and its upcoming pivotal trial, we are exploring strategic alternatives for the ELVN-002 program, and we do not intend to pursue its development beyond 2025. We have not initiated clinical trials for any other product candidate, and we may experience unexpected or adverse results in the future. We will be required to demonstrate thorough, adequate and well-controlled clinical trials that our product candidates are safe and effective, with a favorable benefit-risk profile, for use in their target indications before we can seek regulatory approvals for their commercial sale. Our initial clinical trials will begin with relatively small cohorts before expanding in size in subsequent cohorts. If safety issues arise in an early cohort, we may be delayed or prevented from subsequently expanding into larger trial cohorts. Our ability to generate product revenue, which we do not expect will occur for many years, if ever, will depend heavily on the successful clinical development and eventual commercialization or licensing of ELVN-001. We are not permitted to market or promote any product candidate before it receives marketing approval from the FDA, EMA or any comparable foreign regulatory authorities, and we may never receive such marketing approvals.

We are a clinical stage biopharmaceutical company with a limited operating history upon which you can evaluate our business and prospects. Former Enliven commenced operations in June 2019, has never completed a clinical trial, has no products approved for commercial sale and has never generated any revenue. Drug development is a highly uncertain undertaking and involves a substantial degree of risk. We are devoting substantially all of our resources to developing ELVN-001 and ELVN-002, research and development activities, clinical trial activities, business planning, establishing and maintaining our intellectual property portfolio, hiring personnel, raising capital, and providing general and administrative support for these operations. We are currently evaluating ELVN-001 in a Phase 1 clinical trial in adults with chronic myeloid leukemia ("CML"), and we are evaluating ELVN-002 in Phase 1 clinical trials in adults with solid tumors with HER2 alterations. In addition, we plan to complete our exploratory evaluation of ELVN-002 in combination with Herceptin, Kadcyla, and Enhertu in patients with HER2+ solid tumors in the second half of 2025. To prioritize the advancement of ELVN-001 and its upcoming pivotal trial, we are exploring strategic alternatives for the ELVN-002 program, and we do not intend to pursue its development beyond 2025. We have not initiated clinical trials for any other product candidate. In September 2024, we announced a positive data update from the Phase 1 clinical trial evaluating ELVN-001 in patients with CML that is relapsed, refractory, or intolerant to tyrosine kinase inhibitors ("TKIs"). However, we have not yet demonstrated our ability to complete any clinical trials, obtain marketing approvals, manufacture a commercial-scale product or arrange for a third party to do so on our behalf, develop any required companion diagnostic, or conduct sales and marketing activities necessary for successful product commercialization. As a result, it may be more difficult for investors to accurately predict our likelihood of success and viability than it could be if we had a longer operating history. In addition, we may encounter unforeseen expenses, difficulties, complications, delays and other known and unknown factors and risks frequently experienced by early-stage biopharmaceutical companies in rapidly evolving fields. We also expect that, as we advance our product candidates, we will need to transition from a company with a research and development focus to a company capable of supporting commercial activities. We have not yet demonstrated an ability to successfully overcome such risks and difficulties, or to make such a transition. If we do not adequately address these risks and difficulties or successfully make such a transition, our business will suffer.

Before obtaining marketing approval from regulatory authorities for the sale of our product candidates, we must conduct preclinical studies in animals and extensive clinical trials in humans to demonstrate the safety and efficacy of the product candidates. Clinical testing is expensive and difficult to design and implement, can take many years to complete and has uncertain outcomes. The outcome of preclinical studies and early clinical trials may not predict the success of later clinical trials, and interim results of a clinical trial do not necessarily predict final results. A number of companies in the pharmaceutical and biotechnology industries have suffered significant setbacks in advanced clinical trials due to lack of efficacy or unacceptable safety profiles, notwithstanding promising results in earlier trials. We do not know whether the clinical trials we may conduct will demonstrate adequate efficacy and safety to result in regulatory approval to market any of our product candidates in any jurisdiction. Our product candidates may fail to demonstrate efficacy in humans, and particularly across tumor types. A product candidate may fail for safety or efficacy reasons at any stage of the testing process. A major risk we face is the possibility that none of our product candidates under development will successfully gain market approval from the FDA, EMA or other comparable foreign regulatory authorities, resulting in us being unable to derive any commercial revenue from them after investing significant amounts of capital in their development. If the results of our ongoing or future preclinical studies and future clinical trials are inconclusive with respect to the safety and efficacy of our product candidates, if we do not meet the clinical endpoints with statistical and clinically meaningful significance, or if there are safety concerns associated with our product candidates, we may be prevented or delayed in obtaining marketing approval for such product candidates. In some instances, there can be significant variability in safety and efficacy results between different clinical trials of the same product candidate due to numerous factors, including changes in trial protocols, differences in size and type of patient populations, differences in and adherence to the dose and dosing regimen and other trial protocols and the rate of dropout among clinical trial participants. As is typically the case with oncology drugs, there have been adverse events associated with the use of our product candidates and there could be adverse events caused by our product candidates in the future. Results of our future trials could reveal a high and unacceptable severity and prevalence of side effects, toxicities or adverse events when used alone or in combination with other approved products or investigational new drugs that may result in a safety profile that could prevent regulatory approval, prevent market acceptance, limit their commercial potential or result in significant negative consequences. For example, our trials could be suspended or terminated and the FDA, EMA or comparable foreign regulatory authorities or an IRB could order us to suspend clinical trials, cease further development of or deny approval of our product candidates for any or all targeted indications. This could require us to interrupt, delay or abandon their development or limit development to more narrow uses or subpopulations in which the undesirable side effects or other characteristics are less prevalent, less severe or more acceptable from a risk-benefit perspective. Treatment-related side effects have resulted, and could result in additional patients dropping out of our trials, and could affect patient recruitment and the ability of enrolled subjects to complete the trial or result in potential product liability claims. Any of these occurrences may prevent us from achieving or maintaining market acceptance of the affected product candidate and may harm our business, financial condition and prospects significantly. In addition, our product candidates may be used in populations for which safety concerns may be particularly scrutinized by regulatory agencies. In addition, our product candidates may be studied in combination with other therapies, which may exacerbate adverse events associated with the therapy. Patients treated with our product candidates may also be undergoing surgical, radiation and chemotherapy treatments, which can cause side effects or adverse events that are unrelated to our product candidate but may still impact the success of our clinical trials. The inclusion of critically ill patients in our clinical trials may result in deaths or other adverse medical events due to other therapies or medications that such patients may be using or due to the gravity of such patients' illnesses. For example, it is expected that some of the patients to be enrolled in our future clinical trials will die or experience major clinical events either during the course of our clinical trials or after participating in such trials for non-treatment related reasons. Further, our product candidates could cause undesirable side effects in clinical trials related to on-target toxicity. If on-target toxicity is observed, or if our product candidates have characteristics that are unexpected, we may need to abandon our development or limit development to more narrow indications or subpopulations in which the undesirable side effects or other characteristics are less prevalent, less severe or more acceptable from a risk-benefit perspective. Many compounds that initially showed promise in early-stage testing for treating cancer have later been found to cause side effects that prevented further development of the compound. Even if the side effects do not preclude the product candidate from obtaining or maintaining marketing approval, undesirable side effects may inhibit market acceptance due to the tolerability of our products versus other therapies. Any of these developments could materially harm our business, financial condition and prospects. Further, if any of our product candidates obtains marketing approval, toxicities associated with such product candidates previously not seen during clinical testing may also develop after such approval and lead to a requirement to conduct additional clinical safety trials, additional contraindications, warnings and precautions being added to the drug label including "black box" warnings, significant restrictions on the use of the product or the withdrawal of the product from the market. We cannot predict whether our product candidates will cause toxicities in humans that would preclude or lead to the revocation of regulatory approval based on preclinical studies or early-stage clinical trials.