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

We are a precision oncology company with a limited operating history. Biopharmaceutical product development is a highly speculative undertaking and involves a substantial degree of risk. Since the Company's inception, we have devoted substantially all of our efforts to organizing and staffing our company, acquiring and developing intellectual property, business planning, raising capital, conducting discovery, research and development activities (including conducting clinical trials), and providing general and administrative support for these operations. We have no products approved for commercial sale and therefore have never generated any revenue from product sales, and we do not expect to in the foreseeable future. The revenue that we have generated from our collaboration agreement is also not sufficient to fund our operations. We have not obtained regulatory approvals to market and sell any of our product candidates, and there is no assurance that we will obtain approvals in the future. The FDA has cleared five of our IND applications (TNG908, TNG462,vopimetostat, TNG260, TNG348 and TNG456); however, we have since discontinued development of TNG908 and TNG348. Our other product candidates are still in preclinical development. We expect to continue to incur significant expenses and operating losses over the next several years and for the foreseeable future. Our prior losses, combined with expected future losses, have had and will continue to have an adverse effect on cash and cash equivalent holdings, accumulated deficit, stockholders’ equity and working capital. If we were to expend our cash resources more quickly than we anticipate as we advance into and through the regulatory approval process for our product candidates, our cash runway may be shorter than the target we may disclose from time to time.

 timely complete patient enrollment and patient dosing in our current and future clinical trials (including our current trials of TNG462vopimetostat (as a monotherapy and in combination), TNG456 (as a monotherapy and in combination), and TNG260 and planned clinical trials, including combination clinical trials, with TNG462 and TNG456);

 successfully complete our ongoing clinical trials and any future clinical trials we may initiate (includingincluding, in each case, combination clinical trials);

 successfully enroll the patients with specific cancers and prior treatment that are the focus of our clinical trials, such as patients with limited prior treatment lines in pancreatic and lung cancer for our ongoing monotherapy trialand combination trials for TNG462vopimetostat;

The development of pharmaceutical products is capital-intensive. We are currently advancing our precision oncology programs through clinical and preclinical development. We are actively enrolling patients in twomultiple Phase 1/2 clinical trials, each of which is evaluating safety and efficacy in multiple indications (and we expect to begin enrollment in the TNG456 Phase 1/2 clinical trial in the first half of 2025).indications. We expect our expenses to significantly increase as we continue to advance and complete clinical trials (including multiple combination clinical trials and our pivotal trial), and seek regulatory approval for, our product candidates, including in combination with other therapeutics. Further, we continue our research efforts to identify and advance additional precision oncology compounds that may benefit patients. Even though we completedhave ansuccessfully $80raised capital in the past, including most recently by raising $225.0 million in aggregate gross proceeds from the underwritten offering and concurrent private placement inof Augustcommon 2023shares and receivedpre-funded $41.7warrants millionto purchase common shares in netOctober 2025 and proceeds of $62.1 million from our "at-the-marketat the market" stock offering program induring Januarythe 2024,first quarter of 2026, and through March 2, 2026, we will still be required to raise substantial additional funding in the future in order to continue to fund our operations and advance our clinical trial programs.

We believe that our existing cash, cash equivalents and marketable securities on hand as of December 31, 20242025 will enable us to fund our operating expenses and capital expenditure requirements at least into the third quarter of 2026.2028. However, our future capital requirements will depend on and could increase significantly as a result of many factors (which may result in exhausting such cash resources prior to the third quarter of 2026),factors, including:

 the potential additional expenses attributable to adjusting our development plans if needed (including any supply relatedsupply-related matters or changes to clinical trial protocols);

 the cost of acquiring or supplying therapies to be used in combination clinical trials (such as pembrolizumab, an anti-PD-1 antibody that is used in combination with TNG260);

Until such time, if ever, as we can generate substantial product revenue, we expect to finance our cash needs through one or a combination of private and public equity offerings (such as the underwritten offering and concurrent private placement of our common stockshares and pre-funded warrants in AugustOctober 20232025 and sales of common stock under an "at-the-market" stock offering program in Januaryin 2024the first quarter of 2026), debt financings, collaborations, strategic alliances and licensing arrangements. We do not have any committed external source of funds. The terms of any financing may adversely affect the holdings or the rights of our stockholders and the issuance of additional securities, whether equity or debt, by us, or the possibility of such issuance, may cause the market price of our shares to decline. To the extent that we raise additional capital through the sale of common stock or securities convertible or exchangeable into common stock, the ownership interest of our existing common stockholders will be diluted, and the terms of those securities may include liquidation or other preferences that may materially adversely affect your rights as a common stockholder. Debt financing, if available, would increase our fixed payment obligations and may involve agreements that include covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, acquiring, selling or licensing intellectual property rights, and making capital expenditures, declaring dividends, repurchase shares of our common stock, or other operating restrictions that could adversely impact our ability to conduct our business. We could also be required to meet certain milestones in connection with debt financing and the failure to achieve such milestones by certain dates may force us to relinquish rights to some of our technologies or product candidates or otherwise agree to terms unfavorable to us which could have a material adverse effect on our business, operating results and prospects.

We have not yet demonstrated our ability to complete clinical trials, including large-scale, pivotal clinical trials, obtain regulatory approvals, manufacture a commercial scale product or arrange for a third party to do so on our behalf, or conduct sales and marketing activities necessary for successful commercialization. Although we have received FDA clearance of five IND applications (TNG908, TNG462,vopimetostat, TNG260, TNG348, and TNG456), we have since discontinued development of TNG348 and TNG908. We may not be able to file any future INDs for any of our other product candidates on the timelines we expect, if at all. Further, timelines for developing and filing INDs are subject to significant uncertainties and projected timelines can be delayed. 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 require us to suspend or terminate clinical trials. Any guidance we receive from the FDA or other regulatory authorities 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 result in the imposition of stricter approval conditions than we currently expect. Successful completion of our clinical trials is a prerequisite to submitting an NDA to the FDA, a Marketing Authorization Application, or MAA, to the European Medicines Agency, or EMA, or other marketing applications to regulatory authorities in other jurisdictions, for each product candidate and, consequently, the regulatory approval of each product candidate. While the INDs for TNG908, TNG462,vopimetostat, TNG260, TNG348, and TNG456 were cleared by the FDA, such clearance does not ensure that an adequate number of patients will be enrolled on a timely basis, or at all or that the clinical trials will be completed on time, or at all. For example, in May 2024, we announced that we were discontinuing development of our TNG348 program due to liver toxicity observed in the dose escalation portion of our Phase 1/2 clinical trial, and in November 2024, we announced that we were discontinuing development of TNG908 to fully resource TNG462vopimetostat and TNG456 development.

The discovery and development of oncology therapeutics for patients with genetically defined or biomarker-driven cancers is a rapidly evolving area, and the scientific discoveries that form the basis for our efforts to discover and develop product candidates are relatively new. Our proprietary functional genomics discovery approach is based on the genetic concept of synthetic lethality. The scientific evidence to support the feasibility of developing product candidates based on these discoveries is both preliminary and limited. Although we believe, based on our preclinical work, that the genetic markers targeted by our programs drive the formation and spread of certain cancers, clinical results may not confirm this hypothesis or may only confirm it for certain alterations or certain tumor types. The patient populations for our product candidates (and our combination clinical trials) are limited to those with specific target alterations and may not be completely defined but are substantially smaller than the general treated cancer population, and we will need to screen and identify these patients with targeted alterations. Successful identification of patients is dependent on several factors, including achieving certainty as to how specific alterations respond to our product candidates and the ability to identify such alterations. Furthermore, even if we are successful in identifying patients with specific targets, we cannot be certain that the resulting patient populations with each mutation will be as large as we anticipate, large enough to allow us to successfully obtain approval for each such mutation and commercialize our product candidates and achieve profitability.

We may from time to time indicate the intent to publicly disclose certain clinical trial data at a future date. We have, for example, noted that in 2026 we will provide a clinical update on the TNG462lung cohort of the vopimetostat monotherapy clinical trial and clinicalinitial data onfrom the TNG260Phase 1/2 combination clinical trial inwith 2025.RAS(ON) inhibitors from RevMed. Due to the factors described above, and elsewhere in these Risk Factors, we may be unable to report data on or before the time indicated to investors, we may not have the data to provide the information indicative of safety or efficacy, the data may not be sufficiently mature or the number of patients with a specific histology may be inadequate to draw conclusions about the effectiveness of the therapy, and even if we do provide such clinical trial data, the final results from that phase of the clinical trial may be different from what we disclose initially.

 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 we may fail to enroll patients with certain cancer indications, such as pancreatic and lung cancer, that we are focusing on in connection with TNG462vopimetostat (and GBM, which is our focus for TNG456), 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;

 the cost of clinical trials of our product candidates or of our product candidates in combination with other manufacturer’s commercial products or product candidates may be greater than we anticipate;

 the supply or quality of our product candidates or other materials necessary to conduct clinical trials including our combination clinical trials, of our product candidates (alone or in combination) may be insufficient or inadequate;

 our product candidates (or our product candidates in combination with other products or 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 preclinical or clinical testing of other cancer therapies that raise safety or efficacy concerns about our product candidates;

 regulators may revise the requirements for approving our product candidates, (alone or in combination), or such requirements may not be as we anticipate; and  regulatory developments may occur with respect to our competitors’ products, including any developments, litigation or public concern about the safety of such products.

We may not be able to initiate, continue or complete clinical trials for our product candidates if we are unable to locate and enroll a sufficient number of eligible patients to participate in these trialstrials, including our planned pivotal trial, as required by the FDA or comparable foreign regulatory authorities, or as needed to provide appropriate statistical power for a given trial. In particular, because we are focused on patients with specific genetic mutations for the development of our precision oncology programs and because some of the indications we are pursuing, including pancreatic cancer in connection with TNG462vopimetostat and GBM in connection with TNG456, are orphan indications that have small populations, our ability to enroll eligible patients may be limited or may result in slower enrollment than we anticipate. We also may experience slower enrollment as a result of limited trial populations due to clinical trials run by us or our competitors or other factors beyond our control. Delays in enrollment may affect the timing of any results or data announcements from our trials (as well as the timing for dose escalation and dose expansion) and therefore the regulatory approval (if any) for any of our product candidates may extend beyond the period we have targeted or beyond the timeline expected by investors.

In addition, some of our competitors have ongoing clinical trials for product candidates that aim to treat the same indications as our product candidates, and patients who would otherwise be eligible for our clinical trials may choose instead to enroll in clinical trials of our competitors’ product candidates (for example, multiple INDs for other companies have been cleared by the FDA for clinical trials of MTA-cooperative PRMT5 inhibitors for the treatment of cancer patients, and such trials have already enrolled patients and those trials are using some of the same clinical trial sites that we use). Further, the target patient population eligible for the TNG462vopimetostat and TNG456 clinical trials overlap. In particular, each of these clinical trials has arms that are expected to aim to enroll patients with lung cancer. As a result, our own trials may compete to enroll patients among a limited population and thus each of our own trials may experience delays or limited enrollment or we may be compelled to explore enrollment in new countries to gain access to an expanded patient population.

In addition to the competitive clinical trial environment, the eligibility criteria of our 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. The process of finding patients may prove costly. We also may not be able to identify, recruit or enroll a sufficient number of patients (or sufficient patients who have limited lines of prior therapy) to complete our clinical studiesstudies, including our planned pivotal trial, 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 unavailable or unwilling to participate in our studies for any reason, the timeline for recruiting patients, conducting studies, reporting initial and final trial results and obtaining regulatory approval of potential products may be delayed.

We anticipate that certainCertain of our current and future product candidates are being used in combination or we anticipate could be used in combination with third-party drugs or biologics, some of which are still in development, and we have limited or no control over the supply, regulatory status, or regulatory approval of such other drugs or biologics.

Certain of our current product candidates andare anybeing futureadministered product candidatesor may have the potential to be administered in combination with existing standards of care (such as checkpoint inhibitor immunotherapies, chemotherapies, targeted therapies or radiotherapy) or with other classes of therapeutics agents (such as the RAS(ON) multi- and G12D- inhibitors from RevMed with which we planare toevaluating evaluate TNG462vopimetostat in combination clinical trials and abemaciclib, with which we plan to evaluate TNG456 in a combination clinical trial). Our ability to develop and ultimately commercialize our current programs and product candidates and any future programs or product candidates for use in combination with other therapies will depend on our ability to access such drugs or biologics on commercially reasonable terms for the clinical trials and their availability for use with our commercialized product, if approved. We have entered into separate clinical collaboration and supply agreements with RevMedRevMed, Lilly, and Lilly,Erasca, under which we plan to conduct combination clinical trials with RevMed's RAS(ON) multi- and G12D-selective inhibitorsinhibitors, Lilly's abemaciclib and Lilly'sErasca’s abemaciclib,pan-RAS molecular glue, respectively. Additionally, we planhave to purchasepurchased pembrolizumab for use in combination with TNG462.vopimetostat. Nevertheless, we cannot be certain that current or potential future commercial relationships will continue to provide us with a steady supply of such drugs or biologics on commercially reasonable terms, or at all.

Any failure to maintain or enter into new commercial relationships, or the expense of purchasing checkpoint inhibitor immunotherapies or other potential combination or comparator therapies in the market, may delay our development timelines, increase our costs and jeopardize our ability to develop our current product candidates and any future product candidates as commercially viable therapies. If any of these circumstances occur, our business, financial condition, operating results, stock price and commercial prospects may be materially harmed.

We have oneseveral ongoing and planned clinical trial currentlytrials testing the safety and efficacy of a combination therapytherapies, (TNG260including: is being tested in combination with an anti-PD-1 antibody, pembrolizumab), and have additional clinical trials planned to evaluateevaluating (i) TNG462vopimetostat in multiple different combinations, including with each of RevMed's RAS(ON) multi- and G12D- selective inhibitorsinhibitors, and with pembrolizumab and (ii) TNG456 with abemaciclib. We plan to evaluate vopimetostat with Erasca’s pan-RAS molecular glue. The clinical development of combination therapies may be more complex than the development of single agent therapies and generally requires that we are able to describe and demonstrate the contribution of each product to the safety and efficacy of the combination as a whole. This requirement may make the design and conduct of clinical trials more complex (which may cause delays in the trial or require additional data to be collected and analyzed, which, in turn, may limit any patent protection or regulatory exclusivity periods we have to market the product candidate). In addition, we expect this would increase the anticipated costs that we incur in connection with the seeking regulatory approval of the combination.combination or in commercializing a combination therapy. Further, the FDA's "combination rule" prohibits the FDA approving a fixed-dose combination product unless each component of a proposed drug product contributes to the claimed effects and the dosage of each component (amount, frequency, duration) is safe and effective for the intended population. This typically requires a clinical factorial study, designed to assess the effects attributable to each drug in the combination product, particularly when the ingredients are directed at the same sign or symptom of the disease or condition. Moreover, the applicable requirements for approval of a combination therapy may differ from country to country.

Moreover, following product approval of a combination therapy, the FDA or comparable foreign regulatory authorities may require that products used in conjunction with each other be cross labeled for combined use. To the extent that we do not have rights to the other product, this may require us to work with a third party to satisfy such a requirement (which we aymay be unable to do on reasonable terms, or at all). Moreover, developments related to the other product may impact our clinical trials for the combination as well as our commercial prospects should we receive regulatory approval. Such developments may include changes to the other product’s safety or efficacy profile, changes to the availability of the other product, quality, manufacturing and supply issues with respect to the other product, and changes to the standard of care.

Certain of our product candidates willare bebeing used,tested, and future product candidates may be used, 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 or the combination product may cause negative effects resulting from drug-drug interactions in clinical trials. As is the case with many treatments for cancer and rare 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 the clinical trials of our product candidates or when used in combination with another therapy, we may have difficulty recruiting patients to our clinical trials, patients may drop out of our clinical 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, 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. For example, in May 2024, we announced that we were discontinuing development of our TNG348 program due to liver toxicity observed in the dose escalation portion of our Phase 1/2 clinical trial. Even if the side effects do not preclude the monotherapy or the combination products from obtaining or maintaining regulatory approval, undesirable side effects may inhibit market acceptance of the approved combination products due to their tolerability versus other therapies. Any of these developments could materially harm our business, operating results, financial condition and prospects.

We currently conduct certain clinical trials outside the United States, and expect we will continue to do so in the future, and these jurisdictions may include countries in Europe, Asia, Australia or other foreign jurisdictions. For example, we are conducting clinical trials for TNG462vopimetostat in France and Spain.Spain and anticipate expanding to additional geographies for our upcoming pivotal trial. The acceptance of trial data from clinical trials conducted outside the United States by the FDA, or comparable foreign regulatory authorities, 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 regulatory 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 practices, (ii) the trials were performed by clinical investigators of recognized competence and pursuant to Good Clinical Practices, or GCP, regulations; 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 inspection to be necessary, the FDA is able to validate the data through 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 authorities 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 comparable foreign regulatory authority will accept data from trials conducted outside of the United States or the applicable jurisdiction. If the FDA or any comparable foreign regulatory authority does not accept such data, it would result in the need for additional trials, which would be costly and time-consuming and delay aspects of our business plan, and which may result in our product candidates approval being significantly delayed, or not receiving regulatory approval or clearance for commercialization in the applicable jurisdiction.

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 agencies in the United States and by comparable foreign regulatory authorities. Before we can commercialize any of our product candidates, we must obtain regulatory approval. Although we received FDA clearance of five of our IND applications for each of TNG908, TNG462,vopimetostat, TNG260, TNG348, and TNG456, we have since discontinued development in TNG348 and TNG908. We have not received approval to market any of our product candidates from regulatory authorities in any jurisdiction. 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 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. Securing regulatory approval requires the submission of extensive preclinical and clinical data and supporting information to the various regulatory authorities for each therapeutic indication to establish the product candidate’s safety and efficacy. Securing 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 pharmacokinetics, side effects, toxicities or other characteristics that may preclude our obtaining regulatory 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 and our third-party manufacturers that we expect to rely on for commercial production of our therapies, if approved, may also face greater than expected difficulty in manufacturing our product candidates.

The development and commercialization of new products in the biopharmaceutical and related industries is highly competitive. We compete in the segments of the pharmaceutical, biotechnology, and other related markets that address structural biology-guided chemistry-based drug design to develop therapies in the fields of cancer and genetic diseases. There are many other companies focusing on precision oncology to develop therapies in the fields of cancer and other diseases. Specifically, with respect to TNG462vopimetostat and TNG456, we are aware that Bristol Myers Squibb (which acquired Mirati), Amgen, AstraZeneca, BeigeneBeOne and Abbisko each have a clinical MTA-cooperative PRMT5 inhibitor program that have commenced clinical trials, using the same mechanism of action as TNG462vopimetostat and TNG456. Other companies have announced PRMT5 inhibitor programs, including Gilead Sciences and IDEAYA Biosciences, and they may initiate clinical trials in the near future. Additionally, there are other indirect competitors running clinical trials in the PRMT5 inhibition space, including IDEAYA Biosciences, Beigene,BeOne, Insilico Medicine and Servier Pharmaceuticals, which each have clinical MAT2A inhibitor programs.

The incidence and prevalence for the target patient populations of our programs and product candidates have not been established with precision. TNG462Vopimetostat and TNG456 are both oral small molecule inhibitors of PRMT5. We are developing TNG462vopimetostat for the treatment of patients with solid tumors with MTAP deletion, a genetic alteration that occurs in 10% to 15% of all human tumors, with a particular focus on pancreatic and lung cancer. Our next generation, brain-penetrant PRMT5 product candidate is TNG456. Since TNG456 crosses the blood-brain barrier in preclinical non-human primate models, we intend our development program to havehas a particular focus on patients with GBM. Additionally, TNG260 is a first-in-class, CoREST inhibitor, which reverses the immune evasion effect of STK11 loss-of-function mutations. STK11 loss-of-function mutations are a genetic alteration in approximately 20% of lung, 15% of cervical, 10% carcinoma of unknown primary, 5% of breast and 3% of pancreatic cancers. We are also currently or planning to run clinical trials of vopimetostat in combination with multiple different compounds, including RevMed’s RAS(ON) inhibitors and Erasca's pan-RAS molecular glue. Our projections of both the number of people who have these diseases, as well as the subset of people with these diseases who have the potential to benefit from treatment with our product candidates, are based on our and third parties' estimates.

We do not have the ability to independently conduct clinical trials. We currently rely, and expect to continue to rely, on medical institutions, clinical investigators, contract laboratories and other third parties, such as CROs, to conduct or otherwise support clinical trials for our product candidates, including our current and future Phase 1/2 clinical trials of TNG462,vopimetostat (as a monotherapy and in combination), TNG260 and TNG456, and for any other product candidates that emerge from our precision oncology programs. We may also rely on academic and private non-academic institutions to conduct and sponsor clinical trials relating to our product candidates.

Since we rely on third parties for the execution of clinical trials for our product candidates, we control only certain aspects of their activities that will be important for the conduct of the trial (and such control that we do exercise may be based on contractual provisions that may be breached by the third-party). For example, for the Phase 1/2 clinical trials of TNG462,vopimetostat, TNG456 and TNG260, we are and will rely on the same CRO for the conduct of each of these trials and, depending on the trial, one or a very limited number of manufacturers to manufacture the study drug to be used during the course of the trials. We are responsible for ensuring that each of our clinical trials is conducted and the applicable study drug is manufactured in accordance with the applicable protocol, legal and regulatory requirements and scientific standards, and our reliance on a CRO or CDMO 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, suspension/hold or termination of trials and other penalties up to and including criminal prosecution.

Although we have designed all of our current Phase 1/2 clinical trials,trials and anticipate that we will design our pivotal trial, the operational details of these trials will be executed by CROs, and we expect CROs will conduct all of our future 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.

In addition, funding provided by a collaborator might not be sufficient to advance product candidates under the collaboration. For example, although Gilead provided us with $175.0 million upfront payments and a $20.0 million equity investment in connection with our collaboration, we mighthave since truncated the research term of this collaboration and anticipate that we will need additional funding to advance product candidates prior to thereceiving completion of the applicableany milestones offrom the collaboration agreement with Gilead.

The API we use and that we may continue to use in all of our product candidates is supplied to us from one supplier. The drug product used in our product candidates is supplied by two manufacturers (and the manufacturer that produces the API is also one of the two suppliers of our the drug product used in our current clinical trials). Our ability to successfully develop our product candidates, and to ultimately supply our commercial products in quantities (if approved by regulatory authorities) sufficient to meet the market demand (and to meet requirements in connection with our ongoing and planned clinical trials), depends in part on our ability to obtain the API and drug product for these products in accordance with regulatory requirements and in sufficient quantities for clinical testing and commercialization, when applicable. We are also unable to predict how changing global economic conditions or global health concerns, as well as potential supply chain disruptions or cost increases related thereto, will affect our third-party suppliers and manufacturers. The risks related to global economic and political changes and supply chain disruption could have a material impact since one of our two CDMOs is located in China. Further, this CDMO, which is our sole supplier of API for the drugs used in our clinical trials, is affiliated with WuXi AppTec, and WuXi AppTec has been the subject of proposed Congressional legislation that, if enacted or if the subject of similar executive or administrative action, could restrict WuXi's business in the United States or the ability of businesses in the United States to conduct business with WuXi on national security grounds. We have started the process to locate an alternate producer of API, but there is no guarantee that we can identify and engage an alternate producer or manufacturer in time so as not to disrupt our clinical trials, on terms that are acceptable to us (including financial terms), or at all. Any negative impact of the ability of our CDMOs to deliver API and/or drug product due to political actions, supply chain disruptions or otherwise, may have a material adverse impact on our results of operations or financial condition.

Even if a patent is issued, that is not conclusive as to its inventorship, scope, validity or enforceability and therefore that patent may not afford adequate (or any) protection for our product candidates or future approved products or technology. On the basis of such inconclusiveness, third parties may challenge our patents. Furthermore, patents have a limited lifespan. In the United States and most other jurisdictions in which we have undertaken patent filings, the natural expiration of a patent is generally twenty years after it is filed, assuming all maintenance fees are paid. Given the amount of time required for the development, testing and regulatory review of new product candidates, patents protecting such candidates might expire before or shortly after such candidates are commercialized. Delays in our clinical trials or regulatory approval process may further reduce the effective patent protection period for our products, as patents generally expire 20 years from their earliest filing date regardless of when regulatory approval is obtained. As a result, patents we may own or in-license may not provide us with adequate and continuing patent protection sufficient to exclude others from commercializing drugs similar or identical to our current or future product candidates, including generic versions of our drugs. Nor can we be certain that we will obtain any patent term extension as permitted under the “Hatch-Waxman Amendments” which permit a patent restoration term of up to five years as compensation for patent term lost during product development and the FDA regulatory review process.

Other parties have developed technologies that may be related or competitive to our own, and such parties may have filed or may file patent applications, or may have received or may receive patents, claiming inventions that may overlap or conflict with those claimed in our own patent applications or issued patents, with respect to either the same compounds, methods, formulations or other subject matter, in either case that we may rely upon to dominate our patent position in the market. Publications of discoveries in the scientific literature often lag behind the actual discoveries, and patent applications in the United States and other jurisdictions are typically not published until at least 18 months after the earliest priority date of patent filing, or, in some cases, not at all. Therefore, we cannot know with certainty whether we were the first to make the inventions claimed in patents we may own or in-license patents or pending patent applications, or that we were the first to file for patent protection of such inventions. As a result, the issuance, scope, validity, enforceability and commercial value of our patent rights cannot be predicted with any certainty. Additionally, obtaining broad patent protection for certain method-of-use claims and combination therapies may be challenging due to the existing body of scientific knowledge in these areas, and any patents that do issue may be subject to challenge or may be designed around by competitors.

In some instances, we believe we may prevail in a patent infringement action. There can, however, be no assurance that the court will agree with our position or that it will decide any infringement case in our favor. Nor can we be certain that, if we do not prevail in litigation, that we may be able to obtain a license to any third-party patent on commercially reasonable terms (or at all); successfully develop non-infringing alternatives on a timely basis (or at all); or license alternative non-infringing technology, if any exists, on commercially reasonable terms (or at all). Any impediment to our ability to manufacture, use or sell approved forms of our future products (if approved by regulatory authorities) or our product candidates could have a material adverse effect on our business and prospects.

 a court prohibiting us from developing, manufacturing, marketing or selling our current product candidates, including TNG462,vopimetostat, TNG456 or TNG260 or future product candidates, or from using our proprietary technologies, unless the third party licenses its product, process or other rights to us, which it is not required to do, on commercially reasonable terms or at all;

If the FDA determines that a product candidate offers a treatment for a serious or life-threatening condition and, if approved, the product would provide a significant improvement in safety or effectiveness, the FDA may designate the product candidate for priority review. A priority review designation means that the goal for the FDA to review an application is six months from the date of filing, rather than the standard review period of ten months from the date of filing. We may request priority review for our product candidates. The FDA has broad discretion with respect to whether or not to grant priority review status to a product candidate, so even if we believe a particular product candidate is eligible for such designation or status, the FDA may decide not to grant it. Moreover, a priority review designation does not necessarily result in an expedited regulatory review or approval process or necessarily confer any advantage with respect to approval compared to conventional FDA procedures. Receiving priority review from the FDA does not guarantee approval within the six-month review cycle or at all.

As part of our business strategy, we may seek orphan drug designation for certain of our product candidates, and we may be unsuccessful in obtaining such designation. Regulatory authorities in some jurisdictions, including the United States and Europe, may designate drugs for relatively small patient populations as orphan drugs. Under the Orphan Drug Act, the FDA may designate a drug as an orphan drug if it is a product intended to treat a rare disease or condition, which is generally defined as a patient population of fewer than 200,000 individuals annually in the United States, or a patient population of 200,000 or more in the United States where there is no reasonable expectation that the cost of developing the product will be recovered from sales in the United States. In the United States, orphan drug designation entitles a party to financial incentives such as opportunities for grant funding towards clinical trial costs, tax advantages and user-fee waivers. The FDA granted Orphan Drug Designation to TNG462vopimetostat for the treatment of soft tissue sarcoma and of pancreatic cancer.cancer, and to TNG456 for the treatment of malignant glioma.

We may seek a breakthrough therapy designation for some of our 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 conditioncondition, 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. Product candidates designated as breakthrough therapies by the FDA may also be eligible for rolling review, priority review and 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 therapies considered for approval under conventional FDA 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 such product candidates no longer meet the conditions for qualification and rescind the designation or decide that the time period for FDA review or approval will not be shortened.

We may seek accelerated approval of our current or future product candidates, where applicable, using the FDA’s accelerated approval pathway. A product may be eligible for accelerated approval if it treats a serious or life-threatening condition and generally provides a meaningful advantage over available therapies. In addition, it must demonstrate an effect on a surrogate endpoint that is reasonably likely to predict clinical benefit or on a clinical endpoint that can be measured earlier than irreversible morbidity or mortality, or IMM, that is reasonably likely to predict an effect on IMM or other clinical benefit. As a condition of approval, the FDA requiresmay require that a sponsor of a drug receiving accelerated approval perform adequate and well-controlled post-marketing clinical trials. These confirmatory trials must be completed with due diligence. Under the Food and Drug Omnibus Reform Act of 2022, or FDORA, the FDA is permitted to require that a post-approval confirmatory study or studies be under way prior to approval or, in limited circumstances, within a specified time period after the date accelerated approval was granted. FDORA also requires sponsors to send updates to the FDA every 180 days on the status of such studies, including progress toward enrollment targets, and the FDA must promptly post this information publicly. FDORA also gives the FDA increased authority to withdraw approval of a drug or biologic granted accelerated approval on an expedited basis if the sponsor fails to conduct such studies in a timely manner, send the necessary updates to the FDA, or if such post-approval studies fail to verify the drug’s predicted clinical benefit. Under FDORA, the FDA is empowered to take action, such as issuing fines, against companies that fail to conduct with due diligence any post-approval confirmatory study or submit timely reports to the agency on their progress. In addition, the FDA currently requires, unless otherwise informed by the agency, pre-approval of promotional materials for products receiving accelerated approval, which could adversely impact the timing of the commercial launch of the product. Thus, evenEven if we seek to utilize the accelerated approval pathway, we may not be able to obtain accelerated approval. Even if we do receive accelerated approval, we may not experience a faster development or regulatory review or approval process, and receiving accelerated approval does not provide assurance of traditional FDA approval.

The FDA, the EMA and regulatory authorities in other countries have expressed interest in further regulating biotechnology products. Agencies at both the federal and state level in the United States, as well as U.S. Congressional committees and other governments or governing agencies, have also expressed interest in further regulating the biotechnology industry and the pharmaceutical industry, in particular. Such governmental action or actions may delay or prevent commercialization of some or all of our product candidates. Adverse developments in clinical trials of products conducted by us or by others may cause the FDA or other oversight bodies to change the requirements for conducting clinical trials or for approval of any of our product candidates. These regulatory review agencies and committees and the new requirements or guidelines they promulgate may lengthen the regulatory review process, require us to perform additional studies or 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. As we advance our product candidates, we will be required to consult with these regulatory agencies and comply with applicable requirements and guidelines. If we fail to do so, we may be required to delay or discontinue development of such product candidates. These additional processes may result in a review and approval process that is longer than we otherwise would have expected. Delays as a result of an increased or lengthier regulatory approval process or further restrictions on the development of our product candidates can be costly and could negatively impact our ability to complete clinical trials and commercialize our current and future product candidates in a timely manner, if at all.

DisruptionsGovernment atfunding of the FDA, the EMASEC and other government agencies on which our operations may alsorely, slowand thethose timethat necessaryprovide funding for new product candidates to be reviewedresearch and/or approveddevelopment by necessary government agencies, which would adversely affect our business. Currently, federal agencies in the U.S. are operating under a continuing resolutionactivities that is setrequired by third parties we enter into agreements with, is subject to expirethe onpolitical Marchprocess, 14,which 2025.is inherently fluid and unpredictable. For example, in prior years the U.S. government has shut down several times and certain regulatory agencies, such as the FDA and the SEC, in some instances have had to furlough critical FDA, SEC and other government employees and stop or delay critical activities. A prolonged government shutdown, significant leadership, personnel, and/or policy changes, or other substantial modification in agency activities (including due to global health concerns, the aimspolicies of the Trump administration, and/or geopolitical factors) could significantly impact the ability of the FDA to timely review and process our regulatory submissions, which could have a material adverse effect on our business. Also, state governments may seek to address or react to changes at the federal level with changes to their regulatory frameworks in a manner that could impact our operations.

Increasing efforts by governmental and third-party payors in the United States and abroad to cap or reduce healthcare costs may cause such organizations to limit both coverage and the level of reimbursement for newly approved products and, as a result, they may not cover or provide adequate payment for our product candidates. There has been increasing legislative and enforcement interest in the United States with respect to specialty drug pricing practices. Specifically, there have been several recent 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 Medicare, review the relationship between pricing and manufacturer patient programs, and reform government program reimbursement methodologies for drugs. Recent CMS proposals, including the GLOBE, GUARD, and GENEROUS, could materially impact the Company’s revenue.

 fines, FDA Form 483s, untitled letters, warning letters or other regulatory enforcement action;

We operate globally and, if approved, we may sell our products in countries throughout the world. Significant political, trade, or regulatory developments in the jurisdictions in which we conduct clinical trials, where we may seek to obtain approval of our products or where may sell our products (if approved by regulatory authorities for sale), such as those stemming from the change in U.S. federal administration, are difficult to predict and may have a material adverse effect on us and our operations. Similarly, changes in U.S. federal policy that affect the geopolitical landscape could give rise to circumstances outside our control that could have negative impacts on our business operations. For example, on February 1, 2025, the U.S. imposed a 25% tariff on imports from Canada and Mexico, which were subsequently suspended for a period of one month, and a 10% additional tariff on imports from China (we obtain certain drug product and API from vendors in China andourand our sole supplier of API is located in China). Historically, tariffs have led to increased trade and political tensions. In response to tariffs, other countries have implemented retaliatory tariffs on U.S. goods. Political tensions as a result of trade policies could reduce trade volume, investment, technological exchange and other economic activities between major international economies, resulting in a material adverse effect on global economic conditions and the stability of global financial markets. Any changes in political, trade, regulatory, and economic conditions, including U.S. trade policies, could have a material adverse effect on our financial condition or results of operations.

We are highly dependent on many of our key employees and members of our executive management team as well as the other principal members of our management, scientific and clinical team. Although we have entered into employment letter agreements with our executive officers, each of them may terminate their employment with us at any time. We do not maintain “key person” insurance for any of our executives or other employees. In addition, we rely on consultants and advisors, including scientific and clinical advisors, to assist us in formulating our research and development and clinical trial and commercialization strategies. Our consultants and advisors may be employed by employers other than us and may have commitments under consulting or advisory contracts with other entities that may limit their availability to us. If we are unable to continue to attract and retain high quality personnel, our ability to pursue our growth strategy will be limited.

Like other companies in our industry, we, and our third-party vendors, have experienced threats and cybersecurity incidents relating to our information technology systems and infrastructure. A security breach, incident or compromise, whether through a successful cyberattack, cyber intrusion or otherwise, could result in the theft or destruction of intellectual property, data, or other misappropriation of assets, or otherwise compromise our confidential or proprietary information and disrupt our operations. Cyberattacks are increasing in their frequency, sophistication and intensity, and have become increasingly difficult to detect. Cyberattacks could include wrongful conduct by hostile foreign governments, industrial espionage, wire fraud and other forms of cyber fraud, the deployment of harmful malware, ransomware, the theft, fraud, and subsequent misuse of employee credentials, wrongful conduct by insider employees or vendors, computer viruses, denial-of-service,attacks enhanced or facilitated by AI, denial-of-service attacks, social engineering tactics (including phishing), wrongful intrusion, data breaches, or other means to threaten the security, confidentiality, integrity and availability of our information technology systems and data. A security incident, data breach, incident or compromise, whether through a successful cyberattack or otherwise, could cause serious negative consequences for us, including, without limitation, the disruption of operations, the misappropriation of confidential business information, including the compounds we are developing, our screening platform technology, financial information, trade secrets, financial loss and the disclosure of corporate strategic plans. Attempts to disrupt or gain unauthorized access to our and our third-party service providers’ information systems from malicious third parties or insider threats may incorporate widely varying and frequently changing tactics, which may be enhanced or facilitated by AI. Although we have implemented various measures designed to protect our information technology systems, there can be no assurance that our efforts will prevent security breaches, incidents or other compromises that would result in business, legal, financial or reputational harm to us, or would have a material adverse effect on our results of operations and financial condition. Any failure to prevent or mitigate security breaches, incidents or compromises could lead to improper access to, use of, or disclosure of our proprietary or confidential information (including clinical data or patients’ personal data) and could result in significant liability under various data protection laws, including state (e.g., state breach notification laws), federal (e.g., HIPAA, as amended by HITECH), and international laws (e.g., the GDPR) and may cause a material adverse impact to our reputation, affect our ability to continue existing clinical trials and conduct new clinical trials and potentially disrupt our business.

We rely on our third-party providers to implement effective security measures and identify and correct for any such failures, deficiencies or breaches of our systems. If we or our third-party providers fail to maintain or protect our information technology systems and data integrity effectively or fail to anticipate, plan for or manage significant disruptions to our information technology systems, we or our third-party providers could have difficulty preventing, detecting and controlling cyber-attacks and any such attacks could result in the losses described above as well as disputes with physicians, patients and our partners and collaborators, regulatory sanctions or penalties, increases in operating and other expenses or lost revenue or other adverse consequences, any of which could have a material adverse effect on our business, results of operations, financial condition, prospects and cash flows. Any failure by such third parties to prevent or mitigate security breaches, incidents or compromises, or any improper access to or disclosure of proprietary or confidential information, could have adverse consequences for our business and our reputation. If we are unable to prevent or mitigate the impact of such security breaches, incidents, or other compromises, we could be exposed to litigation and governmental investigations and related fines and penalties. Our contracts may not contain limitations of liability, and even where they do, there can be no assurance that limitations of liability in our contracts are sufficient to protect us from liabilities, damages, or claims related to our privacy and data security obligations. Further, although we maintain cyber liability insurance, this insurance may not provide adequate coverage against potential liabilities related to any experienced cybersecurity incident or breach.

SeveralCertain U.S.state stateslaws havegovern enacted comprehensivethe privacy laws.and security of health information, many of which are not preempted by HIPAA and differ from each other in significant ways, thus complicating compliance efforts. In California, for example, the California Consumer Privacy Act, or CCPA (and its amendments), requires covered businesses to comply with specific privacy and security obligations regarding their handling of personal information of California residents, such as providing the ability to opt-out of certain sales or transfers of their personal information to third parties. The CCPA provides for civil penalties for violations, as well as a private right of action for certain types of data breaches. VariousSimilarly comprehensive privacy laws have been passed in numerous other U.S. states have passed privacy laws that are similar to the CCPA, butwhich contain several key differences in their scope, application and enforcement. Several states have passed laws specifically regulating consumer health information. For example, Washington State’s My Health My Data Act regulates the collection and sharing of consumer health data, which is broadly defined under the law, and includes a private right of action, which could increase the risk of litigation. Similar consumer health laws are in force in Connecticut and Nevada, while other states have proposed or passed legislation that regulates the privacy and security of certain specific types of personal information, including biometric data.

Tango Therapeutics was founded with a clear mission: to discover the next wave of targeted therapies in oncology by addressing the specific genetic alterations that drive cancer. We leverage our state-of-the-art target and drug discovery platformplatforms to identify novel disease-relevant targets and develop newmedicines drugstailored directed at tumor suppressor gene loss into defined patient populations with high unmet medical need. Tumor suppressor gene loss remains a largely unaddressed target space specifically because these genetic events cannot be directly targeted. Our novel small molecules are designed to be selectively active in cancer cells with specific genetic alterations, killing those cancer cells while sparing normal cells. We also are extending this target space beyond the classic, cell-autonomous effects of tumor suppressor gene loss to include the discovery of novel targets that reverse tumor suppressor gene mediated immune evasion which prevents the immune system from recognizing and killing cancer cells. We believe our approach will provide the ability to deliver deep, durable target inhibition with favorable tolerability and safety profiles, thus potentially maximizing clinical benefit.

We are currently developingfocused on clinical development of two MTA-cooperativeMTAP-deleted selective PRMT5 inhibitors: vopimetostat (TNG462) for non-CNS cancers, includingboth pancreaticas a monotherapy and lungin cancer,combination with RAS inhibitors, and TNG456, our next-generation, brain-penetrant PRMT5 inhibitor, for CNS cancers, including GBM.glioblastoma (GBM).

Since the Company's inception, we have focused primarily on organizing and staffing our company, business planning, raising capital, discovering product candidates, securing related intellectual property, and conducting research and development activities for our programs. To date, we have funded our operations primarily through equity financings and from the proceeds received from our collaboration agreement with Gilead. SinceThrough inception,December 31, 2025, we have raised an aggregate of $166.9$1.1 billion from such transactions, including $857.0 million ofin aggregate gross proceeds from the sale of our preferred shares, $342.1 million in gross proceeds through the closing of theour Business CombinationCombination, follow-on public and simultaneousprivate financingofferings, transactions,and through our "at-the-market" stock offering programs, and $237.1 million through our collaboration with GileadGilead. Additionally, during the first quarter of 2026, and $123.0through millionMarch of2, 2026, we have received gross proceeds through (i) $80.0 million from the private placement of common shares and pre-funded warrants to purchase common shares in August 2023 and (ii) $43.0$62.1 million from our "at-the-market" stock offering program.

We expect that our existing cash, cash equivalents and marketable securities on hand as of December 31, 20242025 of $257.9$343.1 millionmillion, will enable us to fund our operating expenses and capital expenditure requirements at least into the third quarter of 2026.2028. Since inception, we have incurred significant operating losses. For the years ended December 31, 2025, 2024, 2023, and 20222023 our net losses were $130.3$101.6 million, $101.7$130.3 million, and $108.2$101.7 million, respectively. We had an accumulated deficit of $501.6$603.2 million as of December 31, 2024.2025. We expect to continue to incur significant and increasing expenses and operating losses for the foreseeable future, as we advance our product candidates through preclinical and clinical development and seek regulatory approvals, manufacture drug product and drug supply, and maintain and expand our intellectual property portfolio. We also expect to hire additional personnel, pay forincur accounting, audit, legal, regulatoryregulatory, consulting, and consulting services, and payother costs associated with maintaining compliance with Nasdaq listing rules and the requirements of the U.S. Securities and Exchange Commission, director and officer liability insurance, investor and public relations activities and other expenses associated with operating as a public company. Our net losses may fluctuate significantly from quarter-to-quarter and year-to-year, depending on the timing of our preclinical studies, our clinical trials, and our expenditures on other research and development activities.

We do not have any product candidates approved for sale and have not generated any revenue from product sales. We will not generate revenue from product sales unless and until we successfully complete clinical development and obtain regulatory approval for our product candidates, if ever. In addition, if we obtain regulatory approval for our product candidates and do not enter into a third-party commercialization partnership, we expect to incur significant expenses related to developing our commercialization capability to support product sales, marketing, manufacturing and distribution activities. As a result, we will need substantial additional funding to support our continuing operations and pursue our growth strategy. Until we can generate significant revenue from product sales, if ever, we expect to finance our operations through a combination of public or private equity offerings and debt financings or other sources, such as potential collaboration agreements, strategic alliances and licensing arrangements. We may be unable to raise additional funds or enter into such other agreements or arrangements when needed on acceptable terms, or at all. Our failure to raise capital or enter into such agreementsagreements, as,as and when needed, could have a negative effect on our business, results of operations and financial condition.

In SeptemberNovember 2022,2025, we entered into a sales agreement (the Leerink Sales Agreement) with JefferiesLeerink Partners LLC (JefferiesLeerink) which permitspermitted us to sell from time to time, at ourits option, up to an aggregate of $100.0 million of shares of its common stock through Jefferies,Leerink, as sales agent. Sales of the common stock, if any, will be made by methods deemed to be "at-the-market" stock offerings. The Leerink Sales Agreement will terminate upon the earliest of: (a) the sale of $100.0 million of shares of the Company's common stock or (b) the termination of the Leerink Sales Agreement by usthe Company or Jefferies.Leerink. As of DecemberMarch 31,2, 2024,2026, we had sold 4,001,2004,953,078 shares of common stock under this stock offering program for gross proceeds of $43.0$62.1 million.

In October 2018, we entered into a collaboration agreement (the 2018 Gilead Agreement) with Gilead Sciences, Inc. (Gilead), under which we received an initial upfront payment of $50.0 million. In August 2020, the 2018 Gilead Agreement was expanded into a broader collaboration via an amended and restated research collaboration and license agreement (the Gilead Agreement)., Pursuantunder to the terms of the Gilead Agreement,which we received an upfront payment of $125.0 million. ConsistentUpfront withpayments thetotaling treatment$175.0 ofmillion theand previouslysubsequent receivedresearch upfrontextension payment,fees thistotaling upfront$24.0 paymentmillion waswere recorded as deferred revenue on our balance sheet and is recognized as revenue as or when the performance obligation under the contract iswas satisfied. In 2020 and 2021, Gilead elected to extend two programs for research extension fees totaling $24.0 million, which was added to our estimate of the transaction price to total $199.0 million. In June 2024, Gilead licensed a program for a $12.0 million fee, which was recognized as license revenue in the second quarter of 2024.

As of December 31, 2024,2025, $136.6all $199.0 million has been recognized as collaboration revenue related to the upfront and research option-extension payments from the Gilead agreements.Agreements.

external research and development expenses incurred under agreements with contract research organizations, or CROs, asvendors well asand consultants that conduct our preclinical studiesand andclinical studies, as well as other development servicesactivities related to our product candidates;

costs to fulfill our obligations under the collaboration with Gilead through August 2025;

Our direct external research and development expenses consist primarily of fees paid to CROsCROs, as well as outside vendors and outside consultants in connection with our preclinical and clinical development and manufacturing activities. Our direct external research and development expenses also include fees incurred under license agreements. We track these external research and development costs on a program-by-program basis once we have identified a product candidate.

The successful development of our product candidates is highly uncertain. We plan to substantially increase our research and development expenses for the foreseeable future as we continue the development of our product candidates and manufacturing processes and conduct discovery and research activities for our preclinical programs. We cannot determine with certainty the timing of initiation, the duration or the completion costs of current or future preclinical studies and clinical trials of our product candidates or the timing of regulatory filings in connection with clinical trials or regulatory approval, due to the inherently unpredictable nature of preclinical and clinical development. Clinical and preclinical development timelines, the probability of success and development costs can differ materially from expectations. We anticipate that we will make determinations as to which product candidates to pursue and how much funding to direct to each product candidate on an ongoing basis in response to the results of ongoing and future preclinical studies and clinical trials, regulatory developments and our ongoing assessments as to each product candidate’s commercial potential. Our clinical development costs have, and are expected to continue to, increase significantly with the commencement and continuation of our current and planned clinical trials, including our planned combination clinical trials. We anticipate that our expenses will increase substantially, particularly due to the numerous risks and uncertainties associated with developing product candidates, including the uncertainty of:

Collaboration revenue of $30.0$62.4 million and $31.5$30.0 million for the years ended December 31, 20242025 and 2023,2024, respectively, was derived from the Gilead collaboration. TheAll decreaseremaining ofdeferred $1.6revenue millionfrom isthe primarilyupfront due to lowerand research costsoption-extension incurredpayments under the collaboration were recognized as revenue during the year ended December 31, 20242025 resultingas ina lowerresult of the truncation of the collaboration revenueagreement recognized.which concluded all research activities.

License revenue ofwas $0 and $12.1 million for the yearyears ended December 31, 20242025 wasand primarily2024, derived from the Gilead collaboration.respectively. The increaserevenue of $7.1 million is primarily due to Gilead licensing a program for $12.0 millionrecognized during the second quarter of 2024 aswas comparedprimarily due to licensing an earlier stagea program to Gilead for $5.0$12.0 million during the year ended December 31, 2023.period.

General and administrative expense was $41.5 million for the year ended December 31, 2025 compared to $43.7 million for the year ended December 31, 2024 compared to $35.5 million for the year ended December 31, 2023.2024. The increasedecrease of $8.2$2.2 million was primarily due to a $6.6 million increasedecrease in personnel-related costscosts, due to an increase inincluding share-based compensation expense and additional headcount.expense.

Interest income was $5.6 million for the year ended December 31, 2025 compared to $7.9 million for the year ended December 31, 2024 compared to $6.6 million for the year ended December 31, 2023.2024. The increasedecrease of $1.3$2.3 million was primarily due to a higher average portfolio balance in 2024 compared to 2023,2025 partiallycombined offset bywith declining rates throughout 2024.2025.

Other income, net was $4.1 million for the year ended December 31, 2025 compared to $7.6 million for the year ended December 31, 2024 compared to $5.9 million for the year ended December 31, 2023,2024, with the increasedecrease beingprimarily attributed to lower accretion onfrom investments purchased at a discount.

Provision for income taxes was less than $0.1 million for the year ended December 31, 2025 compared to $0.2 million for the year ended December 31, 2024 compared to $0.1 million for the year ended December 31, 2023.2024. The income tax provision amount for both periods is primarily attributable to state taxes on interest income earned on marketable securities.

Since our inception, we have generated recurring net losses. We have not yet commercialized any products and we do not expect to generate revenue from sales of any products for several years, if at all. To date, we have funded our operations primarily through equity financings and from the proceeds received from our former collaboration agreement with Gilead. SinceThrough inception,December 31, 2025, we have raised an aggregate of $166.9$1.1 billion from such transactions, including $857.0 million ofin aggregate gross proceeds from the sale of ourpre-public entity preferred shares, $342.1the closing of our Business Combination, follow-on public and private offerings, and through our "at-the-market" stock offering programs, and $237.1 million inthrough our former collaboration with Gilead. Additionally, during the first quarter of 2026, and through March 2, 2026, we have received gross proceeds from the Business Combination and simultaneous financing transactions, $123.0 million of gross proceeds through (i) the $80.0 million private placement of common shares and pre-funded warrants to purchase common shares in August 2023, and (ii) the $43.0$62.1 million from our "at-the-market" stock offering program, and another $237.1 million through our collaboration with Gilead.program. As of December 31, 2024,2025, we had cash and cash equivalents and marketable securities of $257.9$343.1 million.

We expect that our existing cash, cash equivalents and marketable securities on hand as of December 31, 20242025 of $257.9$343.1 million will enable us to fund our operating expenses and capital expenditure requirements at least into the third quarter of 2026.2028. We have based this estimate on assumptions that may prove to be wrong, and we could expend our capital resources sooner than we expect.

Net cash used in operating activities was $131.5$138.9 million for the year ended December 31, 20242025 compared to net cash used in operating activities of $118.0$131.5 million for the year ended December 31, 2023.2024. The increase in net cash used in operating activities for the twelve months ended December 31, 20242025 was primarily due to ana increasedecrease toin operating assets and liabilities, including a deferred revenue decrease driven by the net loss as a resulttruncation of higher operating expenses related to the advancementGilead collaboration in August of our2025, programs and personnel-related costs. The increasewhich was partially offset by changesa decrease in operatingnet assets and liabilities and higher non-cash expenses, including stock-based compensation.loss.

Net cash providedused byin investing activities was $86.1$40.9 million for the year ended December 31, 20242025 compared to net cash provided by investing activities of $41.4$86.1 million for the year ended December 31, 2023.2024. The change was primarily due to aan decreaseincrease in purchases of marketable securities as compared to the year ended December 31, 2023, which was partially offset byand a decrease in sales and maturities of marketable securities as compared to the year ended December 31, 2023.2024.

Net cash provided by financing activities was $47.7$222.5 million for the year ended December 31, 20242025 compared to net cash provided by financing activities of $82.4$47.7 million for the year ended December 31, 2023.2024. The cash provided by financing activities for the twelve months ended December 31, 2025 consisted of the net proceeds received from our underwritten offering and concurrent private placement of common shares and pre-funded warrants to purchase common shares in October 2025 of $211.8 million, as well as the cash provided from the exercises of stock options and ESPP purchases. The cash provided by financing activities for the twelve months ended December 31, 2024 consisted of the $41.7 million in net proceeds received from our "at-the-market" stock offering program in January 2024, as well as the cash provided from the exercises of stock options and ESPP purchases.purchases The cash provided by financing activities for the twelve months ended December 31, 2023 consisted of the net proceeds received from our private placement financing transaction in August 2023 of $79.8 million, as well as the cash provided from the exercises of stock options and ESPP purchases..

Investing in our securities involves a high degree of risk. In addition to the other information set forth in this Quarterly Report on Form 10-Q, careful consideration should be given to the risk factors discussed in Item 1A, “Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2025, which could materially affect our business, financial condition, and/or future results. The risks described in our Annual Report on Form 10-K are not the only risks we face. Additional risks and uncertainties not currently known to us or that we currently deem to be immaterial also may materially adversely affect our business, financial condition, and/or operating results. Other than as set forth below, thereThere have been no material changes to the risk factors set forth in our Annual Report on Form 10-K for the year ended December 31, 2025 as filed with the SEC on March 5, 2026.

Tango Therapeutics was founded with a clear mission: to discover the next wave of targeted therapies in oncology by addressing the specific genetic alterations that drive cancer. We leverage our state-of-the-art target and drug discovery platforms to identify novel disease-relevant targets and develop medicines tailored to defined patient populations with high unmet medical need. Our novel small molecules are designed to be selectively active in cancer cells with specific genetic alterations, killing those cancer cells while sparing normal cells. We believe our approach will provide the ability to deliver deep, durable target inhibition with favorable tolerability and safety profiles, thus potentially maximizing clinical benefit.

We are currently focused on evaluatingclinical development of two MTAP-deleted selective PRMT5 inhibitors: vopimetostat (TNG462) for non-CNS cancers, both as a monotherapy and in combination with RAS inhibitors, givenand theTNG456, overlapour next-generation, brain-penetrant PRMT5 inhibitor, for CNS cancers, including GBM. We are evaluating vopimetostat alone and in combination with RAS inhibitors based on overlapping patient populations, robust preclinical data supporting potential strong combination effect in clinical trials, and favorable clinical efficacy, durability, and safety profiles observed to date with each applicable drug individually. In June 2025, we treated the first patient in our combination clinical trial evaluating vopimetostat with the RAS(ON) multi-selective inhibitor, daraxonrasib, and RAS(ON) G12D-selective inhibitor, zoldonrasib (Revolution Medicines). Both combinations have been generally well-tolerated to date with encouraging early efficacy data. We plan to provide a clinical data update from this study in 2026 and will provide details of our planned path to registration for vopimetostat at that time.

Given the differentiated profile of vopimetostat enabling the potential for efficacious and tolerable RAS inhibitor combinations, in March 2026, we entered into a clinical trial collaboration and supply agreement (CTCSA) with Erasca, Inc., or Erasca,Erasca to evaluate vopimetostat in combination with Erasca’s pan-RAS molecular glue, ERAS-0015. Under the terms of the agreement,CTCSA Tangowith isErasca, we are the sponsor of the trial and Erasca is supplying ERAS-0015 at no cost. We plan to initiate this Phase 1/2 clinical trial in the second half of 2026.

TNG456 is a brain-penetrant PRMT5 inhibitor. In May 2025, the first patient was treated with TNG456 in the dose escalation portion of the Phase 1/2 clinical trial to evaluate the safety, pharmacokinetics, pharmacodynamics and antitumor activity of TNG456 as a monotherapy. The trial is currently enrolling patients with MTAP-deleted solid tumors, with a focus on GBM. We anticipate providing initial clinical data from this trial in the second half of 2026.

Due to an increased focus on our PRMT5 pipeline, we are deprioritizing future development and resources allocated to TNG260.TNG260 TNG260,and a first-in-class CoREST inhibitor that we recently evaluatedare in athe Phaseprocess 1/2of trial, showed limited clinical benefit in patients and we plan to shutshutting down the clinical trial. Additionally, TNG961, a novel molecular glue development candidate targeting HBS1L for degradation in solid tumors in FOCAD-deleted/MTAP-deleted cancers,TNG961 is currently in the IND-enabling phase of development and we do not have current plans to further advance development of this molecule.

Since the Company'sour inception, we have focused primarily on organizing and staffing our company, business planning, raising capital, discovering product candidates, securing related intellectual property, and conducting research and development activities for our programs. To date, we have funded our operations primarily through equity financings and from the proceeds received from our collaboration agreement with Gilead. Through MarchJune 31,30, 2026, we have raised an aggregate of $1.2$1.8 billion from such transactions, including $921.4$1.6 millionbillion in aggregate gross proceeds from the sale of preferred shares, the closing of our Business Combination, follow-on public and private offerings, and through our "at-the-market" stock offering programs, and $237.1 million throughpursuant to our collaboration with Gilead.Gilead, the research portion of which concluded in August 2025.

We expect that our existing cash, cash equivalents and marketable securities on hand as of MarchJune 31,30, 2026 of $379.8$1.0 million,billion, will enable us to meet our current operating plan and fund our operating expenses and capital expenditure requirements intofor 2028.at least twelve months from the issuance of the financial statements in this Quarterly Report. Since inception, we have incurred significant operating losses. For the threesix months ended MarchJune 31,30, 2026 and 2025, our net losses were $45.5$100.9 million and $39.9$78.7 million, respectively. We had an accumulated deficit of $648.7$704.0 million as of MarchJune 31,30, 2026. We expect to continue to incur significant and increasing expenses and operating losses for the foreseeable future,future as we advance our product candidates through preclinical and clinical development and seek regulatory approvals, manufacture drug product and drug supply, and maintain and expand our intellectual property portfolio. We also expect to hire additional personnel, pay for accounting, audit, legal, regulatory and consulting services, and pay costs associated with maintaining compliance with The Nasdaq Stock Market LLC listing rules and the requirements of the U.S. Securities and Exchange Commission,SEC, director and officer liability insurance, investor and public relations activities and other expenses associated with operating as a public company. Our net losses may fluctuate significantly from quarter-to-quarter and year-to-year, depending on the timing of our preclinical studies, our clinical trials, and our expenditures on other research and development activities.

Because of the numerous risks and uncertainties associated with pharmaceutical development, we are unable to predict the timing or amount of increased expenses or when or if we will be able to achieve or maintain profitability. Even if we are able to generate revenues from the sale of our therapies, if approved, we may not become profitable. If we fail to become profitable or are unable to sustain profitability on a continuing basis, then we may be unable to continue our operations at planned levels and be forced to reduce our operations.

Collaboration Agreements with Gilead Sciences

In October 2018, we entered into a collaboration agreement (the 2018 Gilead Agreement) with Gilead Sciences, Inc. (Gilead),Gilead, under which we received an initial upfront payment of $50.0 million. In August 2020, the 2018 Gilead Agreement was expanded into the Gilead Agreement, a broader collaboration via an amended and restated research collaboration and license agreement (the Gilead Agreement),agreement, under which we received an upfront payment of $125.0 million. Upfront payments totaling $175.0 million and subsequent research extension fees totaling $24.0 million were recorded as deferred revenue on our balance sheet and recognized as revenue as or when the performance obligation under the contract was satisfied. In June 2024, Gilead licensed a program for a $12.0 million fee, which was recognized as license revenue in the second quarter of 2024.

In August 2025, the Companywe and Gilead mutually agreed to truncate the research term of the Gilead Agreement from seven to five years, concluding the research portion of the collaboration. There was no financial penalty to the Companyus as a result, no licensed programs were returned to the Company,us, all ongoing work at Gilead on licensed programs will continue and agreements for all future milestones and royalties remain in effect. TheWe Company hashave no future research obligations and the remaining unrecognized deferred revenue balance at the time of truncating the collaboration agreement of $53.8 million was recognized as revenue in the third quarter of 2025.

During the three months ended MarchJune 31,30, 2026 and 2025, we recognized $0 and $5.4$3.2 million, respectively, and during the six months ended June 30, 2026 and 2025, we recognized $0 and $8.6 million, respectively, of collaboration revenue associated with the 2018 Gilead agreementsAgreement and the Gilead Agreement based on performance completed during each period.

external research and development expenses incurred under agreements with contract research organizations, or CROs, vendors and consultants that conduct our preclinical and clinical studies, as well as other development activities related to our product candidates;

Our direct external research and development expenses consist primarily of fees paid to CROs,contract research organizations, as well as outside vendors and consultants in connection with our preclinical and clinical development and manufacturing activities. We track these external research and development costs on a program-by-program basis once we have identified a product candidate.

We do not allocate employee costs or costs associated with our target discovery efforts, laboratory supplies, and facilities, including depreciation or other indirect costs, to specific programs because these costs are deployed across multiple programs and, as such, are not separately classified. We characterize research and development costs incurred prior to the identification of a product candidate as discovery costs. We use internal resources primarily to conduct our research and discovery activitiesactivities, as well as for managing our preclinical, development and manufacturing activities.

***In November 2024, we announced we stopped enrollment in the TNG908 Phase 1/2 trial due to insufficient brain exposure for GBM clinical activity and portfolio prioritization. Expenses beyond November 2024 related to previously enrolled patients and close-out clinical trial costs.

General and administrative expenses consist primarily of employee related costs, including salaries, bonuses, benefits, stock-based compensation and other related costs. General and administrative expenseexpenses also includesinclude professional services, including legal, accounting and audit services and other consulting feesfees, as well as facility costs not otherwise included in research and development expenses, insurance and other general administrative expenses.

We anticipate that our general and administrative expenses will increase in the future as we increase our headcount to support our continued research activities and development of our product candidates. We also anticipate that we will incur increased accounting, audit, legal, regulatory, compliance and director and officer insurance costscosts, as well as investor and public relations expenses associated with operating as a public company.

Our provision for income tax consists of an estimate for U.S. federal and state income taxes based on enacted rates, as adjusted for allowable credits, deductions, uncertain tax positions, changes in deferred tax assets and liabilities and changes in tax law. We recorded an insignificant provision for income taxes for each of the three and six months ended MarchJune 31,30, 2026 and 2025.

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

The following table summarizes our results of operations for the three months ended MarchJune 31,30, 2026 and 2025:

Collaboration revenue of $0 and $5.4$3.2 million for the three months ended MarchJune 31,30, 2026 and 2025, respectively, was derived from the Gilead Agreement. All remaining deferred revenue from the upfront and research option-extension payments under the Gilead Agreement was recognized as collaboration revenue during the year ended December 31, 2025 as a result of the truncation of the collaborationGilead agreementAgreement which concluded all research activities.activities in August 2025.

General and administrative expense was $15.2$22.6 million for the three months ended MarchJune 31,30, 2026 compared to $11.5$11.3 million for the three months ended MarchJune 31,30, 2025. The increase of $3.8$11.2 million was primarily due to an increase in personnel-related costs, including share-based compensation expense.

Interest income was $2.2$3.7 million for the three months ended MarchJune 31,30, 2026 compared to $1.6$1.2 million for the three months ended MarchJune 31,30, 2025, with the increase primarily attributable to a higher marketable securities balance during the firstsecond quarter of 2026 as compared to the same period in the prior year.

Other income, net was $1.1$0.7 million for each of the three months ended MarchJune 31,30, 2026 andcompared to $0.9 million for the three months ended June 30, 2025. In both periods, other income, net, iswas primarily derived from accretion from investments purchased at a discount.

Provision for income taxes was less than $0.1 million for each of the three months ended MarchJune 31,30, 2026 and 2025. The tax provisions arewere insignificant in each of the three months ended MarchJune 31,30, 2026 and 2025.

Since our inception, we have generated recurring net losses. We have not yet commercialized any products and we do not expect to generate revenue from sales of any products for several years, if at all. To date, we have funded our operations primarily through equity financings and from the proceeds received from the Gilead Agreement. Through MarchJune 31,30, 2026, we have raised an aggregate of $1.2$1.8 billion from such transactions, including $921.4$1.6 millionbillion in aggregate gross proceeds from the sale of pre-public entity preferred shares, the closing of our Business Combination, follow-on public and private offerings, and through our "at-the-market" stock offering programs, and $237.1 million throughpursuant to our former collaboration with Gilead.Gilead, the research portion of which concluded in August 2025. As of MarchJune 31,30, 2026, we had cash and cash equivalents and marketable securities of $379.8$1.0 million.billion.

In November 2025, we entered into a sales agreement (the Leerink Sales Agreement) with Leerink Partners LLC (Leerink),Agreement, which permitted us to sell from time to time, at itsour option, up to an aggregate of $100.0 million of shares of itsour common stock through Leerink,Leerink Partners, as sales agent. Sales of the common stock are made by methods deemed to be "at-the-market" stock offerings. The Leerink Sales Agreement will terminate upon the earliest of: (a) the sale of $100.0 million of shares of the Company'sour common stock or (b) the termination of the Leerink Sales Agreement by the Companyus or Leerink.Leerink Partners. During the three months ended MarchJune 31,30, 20262026, we did not sell any shares of our common stock under the Leerink Sales Agreement and during the six months ended June 30, 2026, we sold 5,148,151 shares of common stock under this stock offering program for gross proceeds of $64.4 million. We may, at our option, sell up to approximately $35.6 million of shares of our common stock remaining under this stock offering program.

We expect that our existing cash, cash equivalents and marketable securities on hand as of MarchJune 31,30, 2026 of $379.8$1.0 millionbillion will enable us to meet our current operating plan and fund our operating expenses and capital expenditure requirements intofor 2028.at least twelve months from the issuance of the financial statements in this Quarterly Report. We have based this estimate on assumptions that may prove to be wrong, and we could expend our capital resources sooner than we expect.