Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

The following discussion of our financial condition and results of operations should be read in conjunction with our consolidated financial statements and related notes included elsewhere in this report. Some of the information contained in this discussion and analysis and set forth elsewhere in this report, including information with respect to our plans and strategy for our business, includes forward-looking statements that involve risks and uncertainties. You should review the section entitled “Risk Factors” in Part I - Item 1A of this report for a discussion of important factors that could cause actual results to differ materially from the results described in or implied by the forward-looking statements contained in the following discussion and analysis.

Overview

We are a commercial-stage pharmaceutical company pioneering novel cancer therapies and dedicated to the discovery, development and commercialization of first-in-class drugs directed against nuclear export for the treatment of cancer. Our scientific expertise is based upon an understanding of the regulation of intracellular communication between the nucleus and the cytoplasm. We have discovered and are developing and commercializing novel, small molecule Selective Inhibitor of Nuclear Export (“SINE”) compounds that inhibit the nuclear export protein exportin 1 (“XPO1”). These SINE compounds represent a new class of drug candidates with a novel mechanism of action that have the potential to treat a variety of diseases with high unmet medical need. Our lead asset, XPOVIO® (selinexor), was the first oral XPO1 inhibitor to receive marketing approval, receiving its initial U.S. approval from the U.S. Food and Drug Administration (“FDA”) in July 2019, and is currently approved and marketed in the U.S. for the following indications:

•

In combination with bortezomib and dexamethasone for the treatment of adult patients with multiple myeloma who have received at least one prior therapy. Approval in this indication was based on the results from the BOSTON (Bortezomib, Selinexor and Dexamethasone) trial;

•

In combination with dexamethasone for the treatment of adult patients with relapsed or refractory multiple myeloma who have received at least four prior therapies and whose disease is refractory to at least two proteasome inhibitors, at least two immunomodulatory agents, and an anti-CD38 monoclonal antibody. Approval in this indication was based on the results from the STORM (Selinexor Treatment of Refractory Myeloma) trial; and

•

For the treatment of adult patients with relapsed or refractory diffuse large B-cell lymphoma (“DLBCL”), not otherwise specified, including DLBCL arising from follicular lymphoma, after at least two lines of systemic therapy. This indication was approved under accelerated approval based on response rate and was based on the results from the SADAL (Selinexor Against Diffuse Aggressive Lymphoma) trial. Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial.

The commercialization of XPOVIO in the U.S. is currently supported by sales representatives, nurse liaisons, and a market access team, as well as KaryForward®, an extensive patient and healthcare provider support program. Our commercial efforts are also supplemented by patient support initiatives coordinated by our dedicated network of participating specialty pharmacy providers. We plan to continue to educate physicians, other healthcare providers and patients about XPOVIO’s clinical profile and unique mechanism of action as we continue to expand XPOVIO use.

The commercialization of XPOVIO and NEXPOVIO® (selinexor) (the brand name for selinexor in Europe and the United Kingdom) outside of the U.S. is managed by our partners in their respective territories. XPOVIO/NEXPOVIO has received regulatory approval in various indications in over 45 countries outside the U.S. and is commercially available in a growing number of countries as our partners continue to secure reimbursement approvals.

Our primary focus is on marketing XPOVIO in its currently approved indications as well as developing and seeking the regulatory approval of selinexor as an oral agent targeting multiple high unmet need cancer indications, including our lead clinical programs in myelofibrosis and our other late-stage clinical programs in endometrial cancer and multiple myeloma. We plan to continue to conduct clinical trials and to seek additional approvals for the use of selinexor as a single agent or in combination with other oncology therapies to expand the patient populations that are eligible for treatment with selinexor. As announced in January 2024, further clinical development of our eltanexor program continues to remain on hold in an effort to focus our resources on our prioritized late-stage programs.

In May 2024, we entered into a series of transactions (the “Refinancing Transactions”) to limit our aggregate indebtedness, extend the maturity of certain of our indebtedness and provide us with additional working capital. Pursuant to these transactions, we borrowed $100.0 million from existing lenders and certain entities managed by HealthCare Royalty Management, LLC (“HCRx”) under a $100.0 million senior secured term loan facility (the “Term Loan”) and used a portion of the proceeds of the Term Loan to repay obligations under our existing financing arrangement with HCRx pursuant to an amendment that made other changes to our

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existing financing arrangement with HCRx. We also exchanged, pursuant to privately negotiated agreements, an aggregate principal amount of $148.0 million of our existing 3.00% unsecured convertible senior notes due 2025 (the “2025 Notes”) for (i) $111.0 million aggregate principal amount of new 6.00% secured convertible senior notes due 2029 (the “2029 Notes”) and (ii) warrants to purchase up to 45.8 million shares of our common stock. In addition, HCRx purchased $5.0 million aggregate principal amount of the 2029 Notes through satisfaction of $5.0 million of our existing obligations to HCRx. Please refer to Note 10 “Long-Term Obligations”, to the consolidated financial statements included under Part II, Item 8 of this Annual Report on Form 10-K for additional details of the Refinancing Transactions.

As of December 31, 2024, we had an accumulated deficit of $1.6 billion. We had net losses of $76.4 million, $143.1 million, and $165.3 million for the years ended December 31, 2024, 2023 and 2022, respectively. We recognized total revenue of $145.2 million in 2024, including $112.8 million of XPOVIO net product revenue and $32.4 million of license revenue. License revenue included $15.0 million of revenue for the reimbursement of development related expenses from the Menarini Group (“Menarini”). As of December 31, 2024, we had $108.7 million in cash, cash equivalents and investments. Based on our current business plan and current capital resources, combined with the uncertainty regarding the availability of additional funding and considering our debt obligations, including a requirement to maintain cash, cash equivalents and investments of at least $25.0 million at all times, we have concluded that there is substantial doubt regarding our ability to continue as a going concern within one year after the date the accompanying consolidated financial statements are issued. See “Liquidity, Capital Resources, and Going Concern” below for a further discussion of our liquidity and the conditions that raise substantial doubt regarding our ability to continue as a going concern.

Critical Accounting Estimates

Our discussion and analysis of our financial condition and results of operations are based on our consolidated financial statements, which we have prepared in accordance with U.S. generally accepted accounting principles. The preparation of these consolidated financial statements requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements, as well as the reported amounts of revenues and expenses during the reporting periods. We believe that the estimates and assumptions involved in the accounting policies described below may have the greatest potential impact on our consolidated financial statements and, therefore, consider these to be our critical accounting estimates. We evaluate our estimates and assumptions on an ongoing basis. Actual results may differ from these estimates under different assumptions and conditions. See Note 2, “Summary of Significant Accounting Policies”, to the consolidated financial statements included under Part II, Item 8 of this Annual Report on Form 10-K for information about our significant accounting policies.

Product Revenue Reserves

We recognize product revenue, net of variable consideration related to certain allowances and accruals, when the customer takes control of the product, which is upon delivery to the customer. Revenue from product sales is recorded at the net sales price, which includes estimates of variable consideration for which reserves are reported. These reserves are based on the amounts earned, or to be claimed on the related sales, and are generally classified as reductions of accounts receivable (if the amount is payable to the customer) or a current liability (if the amount is payable to a party other than a customer). Certain amounts are known at the time of sale based on contractual terms and are recorded pursuant to the most likely amount method, which is the single most likely amount in a range of possible considerations. Other amounts are estimated pursuant to the expected value method, which is the sum of probability-weighted amounts in a range of possible consideration amounts. Relevant factors used in the expected value method include: current contractual and statutory requirements, specific known market events and trends, industry data, and forecasted customer buying and payment patterns. These reserves reflect our best estimates of the variable consideration based on the terms of the respective underlying contracts.

The estimates for our product revenue allowances and accruals are most significantly affected by chargebacks, which are contractual commitments to provide products to qualified healthcare entities at prices lower than the list prices charged to our customers who purchase XPOVIO directly from us, and rebates that represent discount obligations under government programs, including Medicaid, Medicare, the Department of Veterans Affairs, the Department of Defense, and others.

A 10% increase or decrease in these estimates would impact net product revenue by a corresponding increase or decrease of approximately $4.0 million.

License Agreements

We generate revenue from license or similar agreements with pharmaceutical companies for the development and commercialization of certain of our products and product candidates.

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At contract inception, we evaluate all goods or services in the agreement to determine if they are distinct. If they are not distinct, they are combined with other promised goods or services to create a bundle of promised goods or services that are distinct. Distinct goods or services and distinct bundles of goods or services are considered performance obligations. Optional future services where any additional consideration paid to us reflects their standalone selling prices do not provide the customer with a material right and, therefore, are not considered performance obligations. Optional future services that are priced in a manner which provides the customer with a significant or incremental discount are considered performance obligations because they provide the customer with a material right.

We utilize judgment to estimate the transaction price at contract inception. We evaluate contingent milestones to determine if they should be included in the transaction price using the most likely amount method. Milestone payments that are not within our control, such as regulatory approvals, are not considered likely of being achieved until those approvals are received and are excluded from the transaction price using the most likely amount method. The transaction price is then allocated to each performance obligation on a relative standalone selling price basis, for which we recognize revenue as or when the performance obligations are satisfied. At the end of each reporting period, we re-evaluate our estimate of the transaction price including the probability of achieving milestone payments that may not be subject to a material reversal and adjust the transaction price if necessary. Any such adjustments are recorded on a cumulative catch-up basis, which would affect license and other revenue in the period of adjustment.

Accrued Research and Development Costs

We estimate our accrued research and development costs by reviewing quotes and contracts, identifying services that have been performed on our behalf, and estimating the associated cost incurred for services performed when we have not yet been invoiced or otherwise notified of the actual cost. Most of our service providers invoice us monthly in arrears for services performed or when contractual milestones are met. We make estimates of our accrued research and development costs at each balance sheet date in our financial statements based on facts and circumstances known to us at that time. We periodically confirm the accuracy of our estimates with the service providers and make adjustments if necessary. The significant estimates in our accrued research and development costs include fees to be paid to contract research organizations (“CROs”) and contract manufacturing organizations (“CMOs”) in connection with research and development activities, as well as fees to be paid to investigative sites in connection with clinical studies, for which we have not yet been invoiced.

We base our expenses related to CROs and CMOs on our estimates of the services performed and efforts expended pursuant to quotes and contracts with CROs and CMOs that conduct research and development activities on our behalf. The payment terms of these agreements are subject to negotiation, vary from contract to contract and may result in uneven payment flows. There may be instances in which payments made to our service providers will exceed the level of services performed and result in a prepayment. In accruing service fees, we estimate the time period over which the services will be performed and the level of effort to be expended in each period. If the actual timing of the performance of services or the level of effort varies from our estimates, we adjust the accrual or prepayment accordingly. Although we do not expect our estimates to be materially different from amounts actually incurred, if our estimates of the status and timing of services performed differ from the actual status and timing of services performed, it could result in us reporting amounts that are too high or too low in any particular period. To date, our estimates have not been materially different than amounts actually incurred.

Refinancing Transactions

Our estimated value of the gain on extinguishment of debt, the embedded derivatives in the 2029 Notes (as defined above) and the liability-classified common stock warrants related to the Refinancing Transactions, were valued using methodologies that incorporate certain unobservable inputs including (i) the volatility of our common stock price, (ii) our estimated credit spread and (iii) an estimate of when the warrants will be exercised based on an option pricing model. See Note 6, “Fair Value Measurements”, and Note 10, “Long-Term Obligations”, to the consolidated financial statements included under Part II, Item 8 of this Annual Report on Form 10-K for additional information.

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Results of Operations

The following table summarizes our results of operations (in thousands, except for percentages):

For the Years Ended December 31,

Operating expenses:

Product Revenue, net (in thousands, except for percentages)

For the Years Ended December 31,

Net product revenue from U.S. commercial sales of XPOVIO for the year ended December 31, 2024 was relatively consistent as compared to the year ended December 31, 2023. XPOVIO net product revenue was adversely impacted year-over-year by higher gross-to-net adjustments in 2024, driven primarily by 340B discounts and Medicare rebates. We expect net product revenue to increase in 2025 as compared to 2024 due to demand growth.

License and Other Revenue (in thousands, except for percentages)

For the Years Ended December 31,

License and other revenue for the year ended December 31, 2024 decreased by $1.6 million as compared to the year ended December 31, 2023 primarily due to a decrease in milestone-related revenue from our other license agreements, offset by an increase in milestone-related and royalty revenue from Menarini. The license agreements with Menarini and Antengene Therapeutics Limited (“Antengene”) are each defined and described in Note 5, “License Agreements”, to the consolidated financial statements included under Part II, Item 8 of this Annual Report on Form 10-K.

We expect license and other revenue to slightly decrease in 2025 as compared to 2024 primarily due to a decrease in milestone-related revenue from our partners.

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Operating Expenses (in thousands, except for percentages)

For the Years Ended December 31,

Cost of Sales

Cost of sales for the year ended December 31, 2024 was relatively consistent with the year ended December 31, 2023. We expect cost of sales to remain relatively consistent in 2025 as compared to 2024.

Research and Development Expenses (in thousands, except for percentages)

For the Years Ended December 31,

Clinical trial and related costs:

Unallocated costs:

At any one time, we have a number of ongoing clinical development programs that we are conducting independently or in collaboration with third parties. We track our external clinical trial and related costs on a program-by-program basis. Our major programs include our lead clinical programs in myelofibrosis and our other late-stage clinical programs in endometrial cancer and multiple myeloma. To the extent that external clinical trial and related costs are not attributable to a major program, they are included in “Other programs” and to the extent external clinical trial and related costs cannot be allocated to a specific program, they are included in “Non-program specific clinical trial and related costs.” We also have unallocated research and development costs, which we do not track on a program-by-program basis. These costs represent expenses incurred across multiple programs or to support our general research and development operations.

Research and development expenses for the year ended December 31, 2024 increased by $4.5 million as compared to the year ended December 31, 2023. The $9.8 million increase in clinical trial and related costs was primarily due to increased activity in each of our ongoing Phase 3 trials, including increased purchases of comparator drugs. These increases were partially offset by a $9.8 million decrease in clinical trial and related costs in other programs. The decrease in personnel costs of $5.7 million was primarily due to a reduction in headcount and contractors for the year ended December 31, 2024 as compared to the year ended December 31, 2023 due to the realization of previously implemented cost reduction initiatives.

We expect our research and development expenses to decrease in 2025 as compared to 2024 due primarily to full enrollment in mid-2024 of our Phase 3 multiple myeloma study and decreased headcount costs, partially offset by an increase in expenses in connection with our ongoing Phase 3 trials in myelofibrosis and endometrial cancer.

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Selling, General and Administrative Expenses (in thousands, except for percentages)

For the Years Ended December 31,

Selling, general and administrative expenses for the year ended December 31, 2024 decreased by $16.4 million as compared to the year ended December 31, 2023. The decrease in personnel costs of $8.8 million and the decrease in stock-based compensation of $1.5 million were primarily due to a reduction in headcount and contractors for the year ended December 31, 2024 as compared to the year ended December 31, 2023 due to our ongoing cost reduction initiatives. The decrease in consulting, professional and other costs of $6.2 million was primarily due to lower commercial-related activities in connection with cost optimization efforts during 2024.

We expect our selling, general and administrative expenses to slightly decrease in 2025 as compared to 2024 due to continued realization of previously implemented cost reduction initiatives.

Other Income (Expense), net(in thousands, except for percentages)

For the Years Ended December 31,

Other income (expense), net for the year ended December 31, 2024 increased by $56.3 million as compared to the year ended December 31, 2023, primarily due to a $44.7 million gain on extinguishment of debt from the Refinancing Transactions and a $28.7 million gain from the remeasurement of embedded derivatives and liability-classified common stock warrants, both of which are non-cash items. These gains were partially offset by an increase in interest expense related to the Term Loan and the 2029 Notes and a decrease in interest income resulting from lower investment balances in 2024 as compared to 2023.

We expect other income (expense), net to decrease in 2025 as compared to 2024 due to the $44.7 million gain on extinguishment of debt being a one-time, non-recurring item. We also expect increased interest expense in 2025 as compared to 2024 on the Term Loan and the 2029 Notes, as both of these instruments were issued in May 2024, and 2025 will include a full year of interest expense on these instruments. The future impact from remeasurements of the embedded derivatives and liability-classified common stock warrants will depend on a variety of factors, including movements in our stock price, and cannot be forecasted.

Results of Operations - Years Ended December 31, 2023 and 2022

Discussion and analysis of the results of operations for the year ended December 31, 2023 as compared to the results of operations for the year ended December 31, 2022 is included under the heading “Item 7.Management’s Discussion and Analysis of Financial Condition and Results of Operations” in our Annual Report on Form 10-K for the year ended December 31, 2023 as filed with the SEC on February 29, 2024 (“2023 Form 10-K”).

Liquidity, Capital Resources and Going Concern

Cash flows

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We anticipate that we will continue to incur significant operating losses in the foreseeable future. Based on our current business plan and current capital resources, combined with the uncertainty regarding the availability of additional funding and considering our debt obligations, including a requirement to maintain cash, cash equivalents and investments of at least $25.0 million at all times, we have concluded that there is substantial doubt regarding our ability to continue as a going concern within one year after the date the accompanying consolidated financial statements are issued. We expect that our cash, cash equivalents and investments as of December 31, 2024 will be sufficient to fund our current operating plans and debt obligation requirements into the fourth quarter of 2025. See “Liquidity, Capital Resources and Going Concern – Funding Requirements” below and Note 1 “Organization and Operations” to the consolidated financial statements included under Part II, Item 8 of this Annual Report on Form 10-K for a further discussion of our liquidity and the conditions that raise substantial doubt regarding our ability to continue as a going concern.

The following table provides information regarding our cash flows (in thousands):

For the Years Ended December 31,

Net Cash Used in Operating Activities

The $34.8 million increase in net cash used in operating activities during the year ended December 31, 2024 as compared to the year ended December 31, 2023 was primarily driven by working capital changes, including the collection of $27.3 million of milestone payments from Antengene in 2023.

Net Cash Provided by Investing Activities

Net cash provided by investing activities increased by $87.5 million during the year ended December 31, 2024 as compared to the year ended December 31,2023. Proceeds from the maturities of investments decreased by $12.7 million in 2024, which was significantly offset by a decrease of $100.3 million in purchases of investments in 2024, due to liquidity needs to fund our operations.

Net Cash Provided by Financing Activities

The $40.5 million increase in net cash provided by financing activities during the year ended December 31, 2024 as compared to the year ended December 31, 2023 was primarily driven by $83.3 million of proceeds from the Term Loan, partially offset by a $40.5 million payment of our deferred royalty obligation to HCRx and a $2.6 million payment of debt issuance costs related to the Refinancing Transactions.

A discussion of changes in our financial condition for the year ended December 31, 2023 as compared to the year ended December 31, 2022 is included under the heading “Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations” in the 2023 Form 10-K.

Sources of Liquidity

On September 14, 2019, we and certain of our subsidiaries entered into the Revenue Interest Financing Agreement with HCRx, which was subsequently amended on June 23, 2021, August 1, 2023 and May 8, 2024 (the “Revenue Interest Agreement” and, as amended, the “Amended Revenue Interest Agreement”), pursuant to which, HCRx paid us a total of $135.0 million, less certain transaction expenses. For additional information on the Amended Revenue Interest Agreement, see Note 10, “Long-Term Obligations”, to the consolidated financial statements included under Part II, Item 8 of this Annual Report on Form 10-K.

On May 8, 2024, we entered into a credit and guaranty agreement (the “Credit Agreement”) with certain existing lenders and HCRx, which provides for a senior secured term loan facility of $100.0 million. For additional information, see Note 10, “Long-Term Obligations”, to the consolidated financial statements included under Part II, Item 8 of this Annual Report on Form 10-K.

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On February 17, 2023, we entered into an Open Market Sale Agreement (the “2023 Open Market Sale Agreement”) with Jefferies LLC, as agent (“Jefferies”). Under the 2023 Open Market Sale Agreement, we may issue and sell shares of our common stock having an aggregate offering price of up to $100.0 million (the “Shares”) from time to time through Jefferies. We did not sell any Shares under the 2023 Open Market Sales Agreement during the year ended December 31, 2024. As of December 31, 2024, $100.0 million of Shares was available for issuance and sale under the 2023 Open Market Sale Agreement.

During the year ended December 31, 2024, we received $19.6 million in milestone and upfront payments under our license and distribution arrangements pursuant to which we are entitled to receive additional milestone payments, if certain development goals and sales milestones are achieved, as well as royalties on future net sales of the licensed and sold products in the territories under such arrangements. In addition, under the Menarini Agreement, Menarini will reimburse us for 25% of all development related expenses we incur for selinexor from 2022 through 2025, provided that such reimbursements shall not exceed $15.0 million per calendar year. We received $15.0 million of reimbursements for development related expenses under the Menarini Agreement during the year ended December 31, 2024.

Commitments, Contingencies and Contractual Obligations

Operating Leases

We are party to an operating lease of office and research space in Newton, Massachusetts, which was amended in November 2024 and under which we currently lease a total of 98,502 square feet of research and office space through September 30, 2025, which will be reduced to 52,224 square feet of solely office space from October 1, 2025 through September 30, 2030. We expect to incur total lease costs of $10.9 million from January 1, 2025 to September 30, 2030.

Contractual Obligations

We have contractual obligations under our (i) 2025 Notes; (ii) Credit Agreement, (iii) 2029 Notes, and (iv) Amended Revenue Interest Agreement as disclosed in Note 10, “Long-Term Obligations”, to the consolidated financial statements included under Part II, Item 8 of this Annual Report on Form 10-K.

Funding Requirements

We expect to continue to incur costs related to our clinical development programs as we continue to advance our lead clinical programs in myelofibrosis and our other late-stage clinical programs in endometrial cancer and multiple myeloma, as well as commercialization expenses related to sales, marketing, manufacturing and distribution of our approved products, to the extent that these functions are not the responsibility of our collaborators.

Identifying potential product candidates and conducting preclinical studies and clinical trials is a time-consuming, expensive and uncertain process that takes years to complete. In addition, our product candidates for which we receive marketing approval may not achieve commercial success. Our ability to become and remain profitable depends on our ability to generate revenue. There can be no assurance as to the amount or timing of any such revenue, and we may not achieve profitability for several years, if at all, as described more fully in the risk factor entitled “We have incurred significant losses since inception, expect to continue to incur significant losses, and may never achieve or maintain profitability,” under the heading “Risk Factors” in this Annual Report on Form 10-K. Accordingly, we will need to continue to rely on additional financing to achieve our business objectives. Adequate additional financing may not be available to us on acceptable terms, or at all. We may seek additional capital due to favorable market conditions or strategic considerations, even if we believe we have sufficient funds for our current or future operating plans. If we are unable to raise capital when needed or on attractive terms, we would be forced to delay, reduce or eliminate our research and development programs or commercialization efforts.

Based on our current business plan and current capital resources, combined with the uncertainty regarding the availability of additional funding and considering our debt obligations, including a requirement to maintain cash, cash equivalents and investments of at least $25.0 million at all times, we have concluded that there is substantial doubt regarding our ability to continue as a going concern within one year after the date the accompanying consolidated financial statements are issued. See Note 1, “Organization and Operations”, to the consolidated financial statements included under Part II, Item 8 of this Annual Report on Form 10-K for a further discussion of the conditions that raise substantial doubt regarding our ability to continue as a going concern. We currently expect that cash, cash equivalents and investments as of December 31, 2024 will be sufficient to fund our current operating plans and debt obligation requirements into the fourth quarter of 2025 while we continue to commercialize XPOVIO in the U.S. and continue the clinical trials of our product candidates. Our future long-term capital requirements will depend on many factors, as described more fully in the risk factor entitled “We will need additional funding to achieve our business objectives. If we are unable to raise capital

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when needed or on acceptable terms, we would be forced to delay, reduce or eliminate our research and development programs and/or commercialization efforts,” under the heading “Risk Factors” in this Annual Report on Form 10-K.

In addition to the expenses required to fund our operations described above, our funding requirements as of December 31, 2024 also include the following:

•

Lease costs for our headquarters in Newton, Massachusetts of $10.9 million through September 30, 2030;

•

Future obligations related to the 2025 Notes of $25.2 million through October 2025;

•

Future obligations related to the 2029 Notes of $146.4 million through May 2029;

•

Future obligations related to the Credit Agreement of $142.7 million through May 2028 in addition to our requirement to maintain cash, cash equivalents and investments of at least $25.0 million at all times; and

•

Future royalty obligations to HCRx under the Amended Revenue Interest Agreement of $119.9 million by October 1, 2031.

Item 7A. Quantitative and Qualitative Disclosures about Market Risk

We are exposed to market risk related to changes in interest rates. We had cash, cash equivalents and investments of $108.7 million as of December 31, 2024. Our primary exposure to market risk is interest rate sensitivity, which is affected by changes in the general level of U.S. interest rates. Due to the short-term duration of our investment portfolio and the low risk profile of our investments, an immediate 100 basis point shift in interest rates would not have a material effect on the fair market value of our investment portfolio.

We do not believe our cash, cash equivalents and investments have significant risk of default or illiquidity. While we believe our cash, cash equivalents and investments do not contain excessive risk, we cannot provide absolute assurance that in the future our investments will not be subject to adverse changes in securities at one or more financial institutions that are in excess of federally insured limits. Given the potential instability of financial institutions, we cannot provide assurance that we will not experience losses on these deposits and investments.

We are also exposed to market risk related to changes in foreign currency exchange rates. We contract with contract research organizations and contract manufacturing organizations that are located in Canada, the United Kingdom and Europe, which are denominated in foreign currencies. We also contract with a number of clinical trial sites outside of the U.S., and our budgets for those studies are frequently denominated in foreign currencies. We are subject to fluctuations in foreign currency rates in connection with these agreements. We do not currently hedge our foreign currency exchange rate risk.

Item 8. Financial Statements and Supplementary Data

The financial statements required to be filed pursuant to this Item 8 are appended to this Annual Report on Form 10-K and are incorporated herein by reference. An index of those financial statements is found in Item 15 of Part IV of this Annual Report on Form 10-K.

Item 9A. Controls and Procedures

Evaluation of Disclosure Controls and Procedures

We have established disclosure controls and procedures designed to ensure that information required to be disclosed in the reports that we file or submit under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the rules and forms prescribed by the Securities and Exchange Commission and is accumulated and communicated to management, including the principal executive officer (our President and Chief Executive Officer) and principal financial officer (our Executive Vice President, Chief Financial Officer and Treasurer), to allow timely decisions regarding required disclosure.

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Our management, under the supervision and with the participation of our President and Chief Executive Officer and Executive Vice President, Chief Financial Officer and Treasurer, has evaluated the effectiveness of our disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act) as of the end of the period covered by this Annual Report on Form 10-K. Management recognizes that any disclosure controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving their objectives. Our disclosure controls and procedures have been designed to provide reasonable assurance of achieving their objectives. Based on such evaluation, our President and Chief Executive Officer and Executive Vice President, Chief Financial Officer and Treasurer concluded that our disclosure controls and procedures were effective at the reasonable assurance level as of December 31, 2024.

Management’s Annual Report on Internal Control Over Financial Reporting

Our management is responsible for establishing and maintaining adequate internal control over financial reporting, as such term is defined in Rules13a-15(f) and15d-15(f) of the Exchange Act. Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with policies or procedures may deteriorate. Our internal control over financial reporting is a process designed under the supervision of our principal executive officer and principal financial officer to provide reasonable assurance regarding the reliability of financial reporting and the preparation of our financial statements for external reporting purposes in accordance with U.S. generally accepted accounting principles.

Under the supervision and with the participation of management, including our principal executive officer and principal financial officer we conducted an evaluation of the effectiveness of our internal control over financial reporting based on the 2013 framework in Internal Control – Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission. Based on our evaluation under that framework, management concluded that our internal control over financial reporting was effective as of December 31, 2024.

Our independent registered public accounting firm that audited the financial statements included in this Annual Report on Form 10-K has issued an attestation report on our internal control over financial reporting, which is included below.

Changes in Internal Control over Financial Reporting

There were no changes in our internal control over financial reporting identified in connection with the evaluation required by Rule 13a-15(d) and 15d-15(d) of the Exchange Act that occurred during the quarter ended December 31, 2024 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

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Report of Independent Registered Public Accounting Firm

To the Shareholders and the Board of Directors of Karyopharm Therapeutics Inc.

Opinion on Internal Control Over Financial Reporting

We have audited Karyopharm Therapeutics Inc.’s internal control over financial reporting as of December 31, 2024, based on criteria established in Internal Control—Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework), (the COSO criteria). In our opinion, Karyopharm Therapeutics Inc. (the Company) maintained, in all material respects, effective internal control over financial reporting as of December 31, 2024, based on the COSO criteria.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the 2024 consolidated financial statements of the Company and our report dated February 19, 2025 expressed an unqualified opinion thereon.

Basis for Opinion

The Company’s management is responsible for maintaining effective internal control over financial reporting and for its assessment of the effectiveness of internal control over financial reporting included in the accompanying Management’s Annual Report on Internal Control Over Financial Reporting. Our responsibility is to express an opinion on the Company’s internal control over financial reporting based on our audit. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audit in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether effective internal control over financial reporting was maintained in all material respects. Our audit included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, testing and evaluating the design and operating effectiveness of internal control based on the assessed risk, and performing such other procedures as we considered necessary in the circumstances. We believe that our audit provides a reasonable basis for our opinion.

Definition and Limitations of Internal Control Over Financial Reporting

A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (2) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

/s/ Ernst & Young LLP

Boston, Massachusetts

February 19, 2025

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Item 9B. Other Information

Director and Officer Trading Arrangements

A portion of the compensation of our directors and officers (as defined in Rule 16a-1(f) under the Securities Exchange Act of 1934, as amended (the “Exchange Act”)) is in the form of equity awards and, from time to time, directors and officers engage in open-market transactions with respect to the securities acquired pursuant to such equity awards or other securities of our company, including to satisfy tax withholding obligations when equity awards vest or are exercised, and for diversification or other personal reasons.

Transactions in our securities by directors and officers are required to be made in accordance with our Insider Trading Policy, which requires that the transactions be in accordance with applicable U.S. federal securities laws that prohibit trading while in possession of material nonpublic information. Rule 10b5-1 under the Exchange Act provides an affirmative defense that enables directors and officers to prearrange transactions in our securities in a manner that avoids concerns about initiating transactions while in possession of material nonpublic information.

During the fourth quarter of 2024, none of our directors or officers adopted or terminated a Rule 10b5-1 trading arrangement or a non-Rule 10b5-1 trading arrangement (as defined in Item 408(c) of Regulation S-K).

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections

Not applicable.

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PART III

Certain information required by Part III is omitted from this Annual Report on Form 10-K and is incorporated by reference from our definitive proxy statement relating to our 2025 annual meeting of stockholders, pursuant to Regulation 14A of the Exchange Act, which we refer to as our 2025 Proxy Statement. We expect to file our 2025 Proxy Statement with the SEC within 120 days of December 31, 2024.

Item 10. Directors, Executive Officers and Corporate Governance

Information regarding our directors, including the audit committee and audit committee financial experts, insider trading policies and procedures and compliance with Section 16(a) of the Exchange Act, if applicable, will be included in our 2025 Proxy Statement and is incorporated herein by reference. Information regarding our executive officers is set forth in “Business - Information about our Executive Officers” in Part I, Item 1 of this Annual Report on Form 10-K.

We have adopted a Code of Business Conduct and Ethics for all of our directors, officers and employees as required by Nasdaq governance rules and as defined by applicable SEC rules. Stockholders may locate a copy of our Code of Business Conduct and Ethics on our website at www.karyopharm.com or request a copy without charge from:

Karyopharm Therapeutics Inc.

Attention: Investor Relations

85 Wells Avenue, 2nd Floor

Newton, MA 02459

We will post to our website any amendments to the Code of Business Conduct and Ethics and any waivers that are required to be disclosed by the rules of either the SEC or Nasdaq.

Item 11. Executive Compensation

The information required by this Item 11 of Form 10-K regarding executive compensation will be included in our 2025 Proxy Statement and, other than the information required by Item 402(v) of Regulation S-K, is incorporated herein by reference.

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

The information required by this Item 12 of Form 10-K regarding security ownership of certain beneficial owners and management and securities authorized for issuance under equity compensation plans will be included in our 2025 Proxy Statement and is incorporated herein by reference.

Item 13. Certain Relationships and Related Transactions, and Director Independence

The information required by this Item 13 of Form 10-K regarding certain relationships and related transactions and director independence will be included in our 2025 Proxy Statement and is incorporated herein by reference.

Item 14. Principal Accountant Fees and Services

The information required by this Item 14 of Form 10-K regarding principal accountant fees and services will be included in our 2025 Proxy Statement and is incorporated herein by reference.

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PART IV

Item 15. Exhibits and Financial Statement Schedules

(a)(1) Financial Statements

The financial statements listed below are filed as a part of this Annual Report on Form 10-K.

Pagenumber

Report of Independent Registered Public Accounting Firm (PCAOB ID 42) 121

Notes to Consolidated Financial Statements 128

(a)(2) Financial Statement Schedules

All financial schedules have been omitted because the required information is either presented in the consolidated financial statements or the notes thereto or is not applicable or required.

(a)(3) Exhibits

The exhibits required by Item 601 of Regulation S-K and Item 15(b) of this Annual Report on Form 10-K are listed in the Exhibit Index immediately preceding the signature page of this Annual Report on Form 10-K and are incorporated herein.

Item 16. Form 10-K Summary

None.

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Report of Independent Registered Public Accounting Firm

To the Shareholders and the Board of Directors of Karyopharm Therapeutics Inc.

Opinion on the Financial Statements

We have audited the accompanying consolidated balance sheets of Karyopharm Therapeutics Inc. (the Company) as of December 31, 2024 and 2023, the related consolidated statements of operations, comprehensive loss, stockholders’ deficit and cash flows for each of the three years in the period ended December 31, 2024, and the related notes (collectively referred to as the “consolidated financial statements”). In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company at December 31, 2024 and 2023, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2024, in conformity with U.S. generally accepted accounting principles.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Company’s internal control over financial reporting as of December 31, 2024, based on criteria established in Internal Control—Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework), and our report dated February 19, 2025 expressed an unqualified opinion thereon.

The Company’s Ability to Continue as a Going Concern

The accompanying consolidated financial statements have been prepared assuming that the Company will continue as a going concern. As discussed in Note 1 to the financial statements, the Company has incurred significant operating losses since inception, expects to incur significant operating losses for the foreseeable future, and has stated that substantial doubt exists about the Company’s ability to continue as a going concern. Management’s evaluation of the events and conditions and management’s plans regarding these matters are also described in Note 1. The consolidated financial statements do not include any adjustments that might result from the outcome of this uncertainty.

Basis for Opinion

These financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on the Company’s financial statements based on our audits. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

Critical Audit Matter

The critical audit matter communicated below is a matter arising from the current period audit of the financial statements that was communicated or required to be communicated to the audit committee and that: (1) relates to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective or complex judgments. The communication of the critical audit matter does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the accounts or disclosures to which it relates.

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Accrued Research and Development Costs

/s/ Ernst & Young LLP

We have served as the Company’s auditor since 2014.

Boston, Massachusetts

February 19, 2025

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Karyopharm Therapeutics Inc.

Consolidated Balance Sheets

(in thousands, except per share amounts)

Assets

Current assets:

Prepaid expenses and other current assets 12,245 11,813

Property and equipment, net 400 606

Operating lease right-of-use assets 5,884 4,276

Liabilities and stockholders’ deficit

Current liabilities:

Operating lease liabilities 438 3,308

Senior secured term loan 94,603 —

Common stock warrants 12,582 —

Operating lease liabilities, net of current portion 6,712 2,789

Stockholders’ deficit:

Accumulated other comprehensive loss (356 ) (161 )

Total liabilities and stockholders’ deficit $ 164,418 $ 240,438

The accompanying notes are an integral part of these consolidated financial statements.

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Karyopharm Therapeutics Inc.

Consolidated Statements of Operations

(in thousands, except per share amounts)

For the Years Ended December 31,

Revenues:

Operating expenses:

Other income (expense):

Gain on extinguishment of debt 44,702 — —

Basic net loss per share (Note 2) $ (0.63 ) $ (1.25 ) $ (2.02 )

Diluted net loss per share (Note 2) $ (0.93 ) $ (1.25 ) $ (2.02 )

The accompanying notes are an integral part of these consolidated financial statements.

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Karyopharm Therapeutics Inc.

Consolidated Statements of Comprehensive Loss

(in thousands)

For the Years Ended December 31,

Other comprehensive income (loss)

Unrealized gain (loss) on investments 133 278 (341 )

Foreign currency translation adjustment (328 ) 199 (488 )

The accompanying notes are an integral part of these consolidated financial statements.

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Karyopharm Therapeutics Inc.

Consolidated Statements of Stockholders’ Deficit

(in thousands)

Shares Amount

Vesting of restricted stock 957 — — — — —

Stock-based compensation expense — — 35,399 — — 35,399

Unrealized loss on investments — — — (341 ) — (341 )

Foreign currency cumulative translation adjustment — — — (488 ) — (488 )

Vesting of restricted stock 1,054 — — — — —

Stock-based compensation expense — — 21,709 — — 21,709

Issuance of common stock warrants — — 239 — — 239

Unrealized gain on investments — — — 278 — 278

Foreign currency cumulative translation adjustment — — — 199 — 199

Vesting of restricted stock 2,436 — — — — —

Shares issued under the employee stock purchase plan 1,978 — 1,452 — — 1,452

Issuance of common stock for financial advisory fee 6,872 1 6,927 — — 6,928

Stock-based compensation expense — — 18,426 — — 18,426

Unrealized gain on investments — — — 133 — 133

Foreign currency cumulative translation adjustment — — — (328 ) — (328 )

The accompanying notes are an integral part of these consolidated financial statements.

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Karyopharm Therapeutics Inc.

Consolidated Statements of Cash Flows

(in thousands)

For the Years Ended December 31,

Operating activities

Adjustments to reconcile net loss to net cash used in operating activities:

Amortization of debt issuance costs and discounts 6,369 814 812

Gain on extinguishment of debt (44,702 ) — —

Changes in operating assets and liabilities:

Investing activities

Purchases of property and equipment (142 ) — (118 )

Financing activities

Proceeds from issuance of senior secured term loan 83,300 — —

Proceeds from issuance of common stock, net of issuance costs — — 189,761

Payment of debt issuance costs (2,588 ) — —

Payment of deferred royalty obligation (40,518 ) — —

Supplemental disclosures:

Cash paid for interest on deferred royalty obligation $ 21,475 $ 16,053 $ 29,273

Lease liabilities arising from obtaining right-of-use assets $ 3,602 $ — $ —

The accompanying notes are an integral part of these consolidated financial statements.

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Karyopharm Therapeutics Inc.

Notes to Consolidated Financial Statements

1. Organization and Operations

We are a commercial-stage pharmaceutical company pioneering novel cancer therapies and dedicated to the discovery, development and commercialization of first-in-class drugs directed against nuclear export for the treatment of cancer. Our scientific expertise is based upon an understanding of the regulation of intracellular communication between the nucleus and the cytoplasm. We have discovered and are developing and commercializing novel, small molecule Selective Inhibitor of Nuclear Export compounds that inhibit the nuclear export protein exportin 1. Our primary focus is on marketing XPOVIO® (selinexor) in its currently approved indications, as well as developing and seeking the regulatory approval of selinexor as an oral agent targeting multiple high unmet cancer indications, including our lead clinical programs in myelofibrosis and our other late-stage clinical programs in endometrial cancer and multiple myeloma. We were incorporated in Delaware on December 22, 2008 and have a principal place of business in Newton, Massachusetts.

Our lead asset, XPOVIO, received its initial U.S. approval from the U.S. Food and Drug Administration (the “FDA”) in July 2019 and is currently approved and marketed for the following indications: (i) in combination with bortezomib and dexamethasone for the treatment of adult patients with multiple myeloma who have received at least one prior therapy; (ii) in combination with dexamethasone for the treatment of adult patients with relapsed or refractory multiple myeloma who have received at least four prior therapies and whose disease is refractory to at least two proteasome inhibitors, at least two immunomodulatory agents, and an anti-CD38 monoclonal antibody; and (iii) for the treatment of adult patients with relapsed or refractory diffuse large B-cell lymphoma (“DLBCL”), not otherwise specified, including DLBCL arising from follicular lymphoma, after at least two lines of systemic therapy. The commercialization of XPOVIO and NEXPOVIO® (selinexor)(the brand name for selinexor in Europe and the United Kingdom) outside of the U.S. is managed by our partners in their respective territories. XPOVIO/NEXPOVIO has received regulatory approval in various indications in over 45 countries outside the U.S. and is commercially available in a growing number of countries as our partners continue to secure reimbursement approvals.

We have historically financed our operations primarily through a combination of proceeds from (i) product revenue sales, (ii) public and private placements of equity securities, (iii) the issuance of convertible debt, (iv) a term loan, (v) our deferred royalty obligation, (vi) at the market offerings and (vii) business development activities. As of December 31, 2024, we had an accumulated deficit of $1.6 billion. We have incurred significant operating losses since our inception and we anticipate that we will continue to incur significant operating losses to maintain our research and development programs, including as we continue to develop and seek regulatory approval of selinexor for multiple cancer indications, and to support our continued operations. As a result, our continued operations are dependent on our ability to raise additional funding and marketing XPOVIO in its currently approved indications. Based on our current business plan and current capital resources, combined with the uncertainty regarding the availability of additional funding and considering our debt obligations, including a requirement to maintain cash, cash equivalents and investments of at least $25.0 million at all times, we have concluded that there is substantial doubt regarding our ability to continue as a going concern within one year after the date these consolidated financial statements are issued. We plan to address the conditions that raise substantial doubt regarding our ability to continue as a going concern by, among other things, obtaining additional funding through equity offerings, debt financings and refinancings, collaborations, strategic alliances and/or licensing arrangements. However, there is no assurance that such additional funding will be available on terms acceptable to us, or at all. We may also be required to reduce our current spending requirements where possible.

If we utilize our capital resources more quickly than anticipated or are unable to obtain additional funding, we may have to significantly curtail, delay, reduce or eliminate one or more of our research and development programs or any current or future commercialization efforts for one or more of our products or product candidates, which could materially adversely affect our business, financial condition, and results of operations. If we are unable to continue as a going concern, we may have to liquidate our assets and may receive less than the value at which those assets are carried on our financial statements, and it is likely that investors will lose all or part of their investment. If we seek additional financing to fund our business activities in the future, investors or other financing sources may be unwilling to provide funding to us on commercially reasonable terms, if at all. The accompanying consolidated financial statements do not include any adjustments to the carrying amounts and classification of assets and liabilities that may be necessary if we were unable to continue as a going concern.

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2. Summary of Significant Accounting Policies

Basis of Presentation and Principles of Consolidation

The accompanying consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and include the accounts of (i) Karyopharm Therapeutics Inc., (ii) Karyopharm Securities Corp. (“KSC”), our wholly-owned Massachusetts corporation incorporated in December 2013 and dissolved in October 2024, (iii) Karyopharm Europe GmbH, our wholly-owned German limited liability company, incorporated in September 2014, and (iv) Karyopharm Israel Ltd., our wholly-owned Israeli subsidiary formed in June 2018. All intercompany balances and transactions have been eliminated in consolidation.

Recent Accounting Pronouncements

In December 2023, the Financial Accounting Standards Board issued Accounting Standards Update 2023-09, Improvements to Income Tax Disclosures, which requires entities to disclose disaggregated information about their effective tax rate reconciliation as well as expanded information on income taxes paid by jurisdiction. The disclosure requirements will be applied on a prospective basis, with the option to apply them retrospectively. The standard is effective for fiscal years beginning after December 15, 2024. We are currently evaluating the disclosure requirements related to this new standard.

Segment Information

Operating segments are defined as components of an enterprise whose operating results are regularly reviewed by the Chief Operating Decision Maker ("CODM") to allocate resources and assess performance. We view our operations and manage our business as a single operating segment, which is the business of discovering, developing and commercializing drugs to treat cancer. All our revenue and all our long-lived assets are attributable to the United States and to our single operating segment.

Our CODM is our Chief Executive Officer who uses net loss as reported on the consolidated statements of operations to monitor budget versus actual results and to ensure we have sufficient capital resources to develop and seek regulatory approval of our product candidates. The following table presents the significant revenue and expense categories in our single operating segment:

For the Years Ended December 31,

(1) Excludes stock-based compensation expense

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period.

On an ongoing basis, we evaluate our estimates, including estimates related to our net product revenue, license and other revenue, clinical trial accruals, stock-based compensation expense, interest expense on our deferred royalty obligation, embedded derivative liabilities, liability-classified common stock warrants, valuation allowances, and other reported amounts of expenses during the reported period. We base our estimates on historical experience and other market-specific or relevant assumptions that we believe to be reasonable under the circumstances. Although we regularly assess these estimates, actual results could differ from those estimates. Changes in estimates are recorded in the period in which they become known.

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Concentrations of Credit Risk and Off-Balance Sheet Risk

Financial instruments which potentially subject us to credit risk consist primarily of cash, cash equivalents and investments. We hold these investments in highly rated financial institutions, and, by policy, limit the amounts of credit exposure to any one financial institution. These amounts at times may exceed federally insured limits. We have not experienced any credit losses in such accounts and do not believe we are exposed to any significant credit risk on these funds. We have no off-balance sheet concentrations of credit risk.

The following table summarizes customers that represent 10% or greater of our consolidated total revenue:

For the Years Ended December 31,

The following table summarizes customers with amounts due that represent 10% or greater of our consolidated accounts receivable, net balance:

As of December 31,

Fair Value Measurements

Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. We disclose information on all assets and liabilities reported at fair value that enables an assessment of the inputs used in determining the reported fair values. The fair value hierarchy prioritizes valuation inputs based on the observable nature of those inputs. The fair value hierarchy applies only to the valuation inputs used in determining the reported fair value and is not a measure of credit quality. The hierarchy defines three levels of valuation inputs:

Level 1 inputs: Quoted prices in active markets for identical assets or liabilities

Level 2 inputs: Inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly

Level 3 inputs: Unobservable inputs that reflect our own assumptions about the assumptions market participants would use in pricing the asset or liability.

Cash and Cash Equivalents

Cash and cash equivalents consist primarily of demand deposit accounts and deposits in short-term money market funds. Cash equivalents are stated at cost, which approximates fair value. We consider all highly liquid investments with maturities of three months or less from the date of purchase to be cash equivalents. We do not hold any money market funds with significant liquidity restrictions that would be required to be excluded from cash equivalents.

Investments

We determine the appropriate classification of our investments at the time of purchase. All of our investments are reported as short-term as they are available for use during the normal cycle of business. We review any investment when its fair value is less than its amortized cost and when evidence indicates that the investment’s carrying amount is not recoverable within a reasonable period. We evaluate whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, we consider the extent to which fair value is less than amortized cost, any changes to the rating of the security by a rating agency, and adverse

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conditions specifically related to the security, among other factors. If this assessment indicates that a credit loss exists and if the present value of cash flows expected to be collected is less than the amortized cost basis, an allowance is recorded on our consolidated balance sheet, limited by the amount that the fair value is less than the amortized cost basis. Any impairment that is not related to a credit loss is recognized in other comprehensive income (loss).

Changes in the allowance for credit losses are recorded as a provision for (or reversal of) credit loss expense. Losses are charged against the allowance when we believe the uncollectability of an investment is confirmed or when either of the criteria regarding intent or requirement to sell is met.

Accounts Receivable

Amounts are recorded as accounts receivable when our right to consideration is unconditional other than the passage of time. Accounts receivable consists of amounts due from customers, net of customer allowances for cash discounts and chargebacks. Our contracts with customers have standard payment terms that generally require payment within 31 to 68 days. We analyze accounts for collectability and periodically evaluate the creditworthiness of our customers. We determined an allowance for credit losses was not material as of December 31, 2024 and 2023 as we have had no bad debt write-offs to date and we do not currently have credit issues with any customers.

Accrued Research and Development Costs

We estimate our accrued research and development costs by reviewing quotes and contracts, identifying services that have been performed on our behalf, and estimating the associated cost incurred for services performed when we have not yet been invoiced or otherwise notified of the actual cost. Most of our service providers invoice us monthly in arrears for services performed or when contractual milestones are met. We make estimates of our accrued research and development costs at each balance sheet date in our financial statements based on facts and circumstances known to us at that time. We periodically confirm the accuracy of our estimates with the service providers and make adjustments if necessary. The significant estimates in our accrued research and development costs include fees to be paid to contract research organizations (“CROs”), and contract manufacturing organizations (“CMOs”) in connection with research and development activities as well as fees to be paid to investigative sites in connection with clinical studies, for which we have not yet been invoiced.

Deferred Royalty Obligation

We treat the debt obligation to HealthCare Royalty Partners III, L.P. and HealthCare Royalty Partners IV, L.P. (“HCRx”), as discussed further in Note 10, “Long-Term Obligations”, as a deferred royalty obligation, amortized using the effective interest rate method over the estimated life of the revenue streams. We recognize interest expense thereon using the effective rate, which is based on our current estimates of future revenues over the life of the arrangement. We periodically assess our expected revenues using internal projections, impute interest on the carrying value of the deferred royalty obligation, and record interest expense using the imputed effective interest rate. To the extent our estimates of future revenues are greater or less than previous estimates or the estimated timing of such payments is materially different than previous estimates, we will account for any such changes by adjusting the effective interest rate on a prospective basis, which will adjust future interest expense with a corresponding impact to the classification of our deferred royalty obligation. The assumptions used in determining the expected repayment term of the deferred royalty obligation and amortization period of the issuance costs requires that we make estimates that could impact the short-term and long-term classification of such costs, as well as the period over which such costs will be amortized.

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Embedded Derivatives

Embedded derivatives that require bifurcation are separated from the host debt instrument and are measured at fair value at the end of each reporting period. See Note 6, “Fair Value Measurements”, for additional detail on the valuation methodology. Changes in fair value are recognized as a component of other income (expense), net on our consolidated statements of operations. Embedded derivatives are reported in the same line as the host debt instrument on the consolidated balance sheets.

Common Stock Warrants

We classify our common stock warrants in stockholder’s equity if they allow for settlement only in shares of our common stock, are indexed to our common stock, and meet the criteria for equity classification. Common stock warrants that do not meet the criteria for equity classification are classified as liabilities and are measured at fair value at the end of each reporting period. See Note 6, “Fair Value Measurements”, for additional detail on the valuation methodology.

Revenue Recognition

To determine revenue recognition, we perform the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) we satisfy a performance obligation. At contract inception, we assess whether the goods or services promised within a contract with a customer are distinct and, therefore, represent a separate performance obligation. Goods or services that are determined not to be distinct are combined with other promised goods and services until a distinct bundle is identified. We then determine the transaction price, which is the total amount of consideration we expect to receive from a customer in exchange for the promised goods or services and includes an estimate of any variable consideration in the contract. We then allocate the transaction price to each performance obligation and recognize the associated revenue when (or as) our customer obtains control of the goods or services within the performance obligation.

Incremental costs of obtaining a contract with a customer are capitalized and amortized consistent with the pattern of transferring the goods or services to which the cost relates when the expected amortization period of the asset is greater than one year. Incremental costs are expensed as incurred if the expected amortization period of the asset that we would have recognized is one year or less.

Product Revenue Recognition

We ship XPOVIO in the U.S. to specialty pharmacies and specialty distributors, collectively referred to as our customers, under a limited number of distribution arrangements with such third parties. Our specialty pharmacy customers resell XPOVIO directly to patients, while our specialty distributor customers resell XPOVIO to healthcare entities, who then resell XPOVIO to patients. We also enter into certain arrangements with group purchasing organizations and/or other payors that provide for government mandated and/or privately negotiated rebates, chargebacks, and discounts with respect to the purchase of our products.

Each unit of XPOVIO that is ordered by our customers represents a distinct performance obligation that is completed when control of the product is transferred to the customer. Accordingly, we recognize product revenue when the customer obtains control of our product, which occurs at a point in time, upon delivery pursuant to our agreements with our customers. If taxes are collected from customers relating to product sales and remitted to governmental authorities, they are excluded from revenue.

Revenue from product sales is recorded at the net sales price, which includes estimates of variable consideration for which reserves are reported. These reserves, as detailed below, are based on the amounts earned, or to be claimed on the related sales, and are generally classified as reductions of accounts receivable (if the amount is payable to the customer) or a current liability (if the amount is payable to a party other than a customer). Certain amounts are known at the time of sale based on contractual terms and are recorded pursuant to the most likely amount method, which is the single most likely amount in a range of possible considerations. Other amounts are estimated pursuant to the expected value method, which is the sum of probability-weighted amounts in a range of possible consideration amounts. Relevant factors used in the expected value method include: current contractual and statutory requirements, specific known market events and trends, industry data, and forecasted customer buying and payment patterns. These reserves reflect our best estimates of the variable consideration based on the terms of the respective underlying contracts.

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The following are the components of variable consideration related to product revenue:

Cash discounts and distributor fees: We provide customary discounts on XPOVIO sales to our customers for prompt payment, the terms of which are explicitly stated in our contracts with such customers. We also pay fees to our customers for sales order management, data, and distribution services, the terms of which are also explicitly stated in our contracts with such customers. Such fees are not for a distinct good or service and, accordingly, are recorded as a reduction of revenue, as well as a reduction to accounts receivable (cash discounts) or as a component of accrued expenses (distributor fees).

Product returns: Consistent with industry practice, we offer our customers and other indirect purchasers a limited right of return for purchased units of XPOVIO for damage, defect, recall, and/or product expiry (beginning three months prior to the product’s expiration date and ending six to twelve months after the product’s expiration date). We estimate the amount of product sales that will be returned using quantitative and qualitative considerations, such as visibility into the inventory remaining in the distribution channel and historical returns data. Reserves for estimated returns are recorded as a reduction of revenue in the period that the related revenue is recognized, as well as a component of accrued expenses. We update our estimated return liability each reporting period based on actual shipments of XPOVIO subject to contractual return rights, changes in expectations about the amount of estimated and/or actual returns, and other qualitative considerations.

Chargebacks: Chargebacks for fees and discounts represent the estimated obligations resulting from our contractual commitments to provide products to qualified healthcare entities at prices lower than the list prices charged to our customers who purchase XPOVIO directly from us. Our customers charge us for the discount provided to the healthcare entities. Chargebacks are generally determined at the time of resale to the qualified healthcare provider by our customers. Accordingly, reserves for chargebacks consist of credits that we expect to issue for units that remain in the distribution channel inventory at the end of the reporting period that we expect will be sold to qualified healthcare entities, as well as chargebacks that customers have claimed, but for which we have not yet issued a credit. We record reserves for chargebacks based on contractual terms in the same period that the related revenue is recognized, resulting in a reduction of product revenue and accounts receivable. We generally issue credits to the customer for such amounts within a few weeks after the customer notifies us of the resale to a discount-eligible healthcare entity.

Government rebates: We are subject to discount obligations under state Medicaid programs, Medicare, the Department of Veterans Affairs, the Department of Defense, and others. These reserves are recorded in the same period the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability, which is included as a component of accrued expenses. For Medicare, we estimate the number of patients in the prescription drug coverage gap for whom we will owe an additional liability under Medicare Part D. Our liability for these rebates consists of invoices received for claims from prior and current quarters that have not been paid or for which an invoice has not yet been received, estimates of claims for the current quarter, and estimated future claims that will be made for product that has been recognized as revenue, but which remains in distribution channel inventories at the end of the reporting period.

Other incentives: Other incentives offered by us include co-payment assistance, which we provide as financial assistance to patients with commercial insurance that requires prescription drug co-payments by the patient. We calculate the accrual for co-payment assistance based on estimates of claims and the average co-payment assistance amounts per claim that we expect to receive associated with sales of XPOVIO that have been recognized as revenue but remain in distribution channel inventories at the end of the reporting period. Such estimates are based on industry experience with similar products, as well as actual amounts from our product sales to date. Any adjustments to such estimated liabilities on units in the distribution channel at period end, as well as actual amounts incurred on units sold through the distribution channel during the period, are recorded in the same period that the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability, which is included as a component of accrued expenses.

Product revenue reserves and allowances: As noted above, cash discounts and chargebacks are recorded as reductions of accounts receivable and product returns, distributor fees, government rebates, and other incentives are recorded as a component of accrued expenses. Actual amounts of consideration ultimately received may differ from our estimates. If actual results in the future vary from our estimates, we will adjust these estimates, which would affect product revenue, net and earnings in the period in which such variances become known.

License Agreements

We generate revenue from license or similar agreements with pharmaceutical companies for the development and commercialization of certain of our products and product candidates. Such agreements may include the transfer of intellectual property rights in the form of licenses, transfer of technological know-how, delivery of drug substances, research and development services, and participation on certain committees with the counterparty. Payments made by the customer may include non-refundable upfront

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fees, payments upon the exercise of options, payments based upon the achievement of defined milestones, and royalties on sales of products and product candidates if they are approved and commercialized. Our license agreements are detailed in Note 5, “License Agreements”.

We utilize judgment to estimate the transaction price at contract inception. We evaluate contingent milestones to determine if they should be included in the transaction price using the most likely amount method. Milestone payments that are not within our control, such as regulatory approvals, are not considered likely of being achieved until those approvals are received and are excluded from the transaction price using the most likely amount method. The transaction price is then allocated to each performance obligation on a relative standalone selling price basis, for which we recognize revenue as or when the performance obligations are satisfied. At the end of each reporting period, we re-evaluate our estimate of the transaction price, including the probability of achieving milestone payments that may not be subject to a material reversal, and adjust the transaction price if necessary. Any such adjustments are recorded on a cumulative catch-up basis, which would affect license and other revenue in the period of adjustment.

We then determine whether the performance obligations are satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue. We evaluate the measure of progress, as applicable, for each reporting period and, if necessary, adjust the measure of performance and related revenue recognition.

When consideration is received, or such consideration is unconditionally due, from a customer prior to transferring goods or services to the customer under the terms of a contract, a contract liability is recorded within deferred revenue. Contract liabilities within deferred revenue are recognized as revenue after control of the goods or services is transferred to the customer and all revenue recognition criteria have been met.

For arrangements that include a license of intellectual property and sales-based royalties, including sales-based milestone payments, we recognize revenue when the related sales occur because the license of intellectual property is deemed to be the predominant item to which the royalties relate.

Research and Development Expenses

Research and development costs are charged to expense as incurred and include, but are not limited to:

•

employee-related expenses, including salaries, benefits, travel and stock-based compensation expense;

•

expenses incurred under agreements with CROs, CMOs and consultants that help conduct clinical trials and preclinical studies;

•

the cost of acquiring, developing and manufacturing clinical trial materials, including comparator products;

•

facilities, depreciation and other expenses, which include direct and allocated expenses for rent and maintenance of facilities, insurance and other supplies; and

•

costs associated with preclinical activities and regulatory operations.

Costs for certain research and development activities, such as clinical trials, are recognized based on various inputs, including an evaluation of the progress to completion of specific tasks using data such as patient enrollment, clinical site activations, and other information provided to us by our vendors based on their actual costs incurred. Payments for these activities are based on the terms of the individual arrangements, which may differ from the pattern of costs incurred, and are accordingly reflected in our financial statements as prepaid or accrued research and development costs.

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Selling, General and Administrative Expenses

Selling, general and administrative costs are charged to expense as incurred and consist primarily of salaries, benefits, travel, and other related costs, including stock-based compensation, for personnel in executive, finance, commercial and administrative functions. Other significant costs include facility costs not otherwise included in research and development expenses, legal fees relating to patent and corporate matters and fees for accounting and consulting services.

Accounting for Stock-Based Compensation

We grant stock-based awards to employees and non-employees, including stock options, restricted stock units (“RSUs”), performance-based restricted stock units (“PSUs”) and shares issued under our employee stock purchase plan (“ESPP”). We account for all stock-based awards at their fair value as of the grant date and recognize compensation expense on the consolidated statements of operations on a straight-line basis over the vesting period of the award. We use the Black-Scholes option pricing model to determine the fair value of stock options as of the grant date. The fair value of RSUs is the quoted closing market price per share of our common stock on the Nasdaq Global Select Market on the grant date. Forfeitures are recognized as they occur.

PSUs are awards which will vest if certain performance goals are achieved over a certain performance period. Certain portions of certain PSU awards vest based on continuous service to the Company throughout the performance period even if the performance goal is not achieved. Stock-based compensation expense for PSUs is determined using the grant date fair value, which is the quoted closing market price per share of our common stock on the Nasdaq Global Select Market on the grant date. The grant date fair value of PSUs with a market condition also includes a discount that represents the likelihood that the related performance goals will not be achieved. Stock-based compensation expense for PSUs with a market condition is recognized on a straight-line basis over the service period. Market conditions include goals related to the performance of our common stock. Stock-based compensation expense for PSUs without a market condition is not recognized until the achievement of the performance goal is deemed probable (the “Probable Date”). At the Probable Date, we record a cumulative catch-up expense for the portion of the grant date fair value attributable to the period from the grant date to the Probable Date. The remaining expense is recognized over the remaining service period on a straight-line basis.

Foreign Currency Transactions

The functional currency of our subsidiaries in Germany and Israel are the Euro and Shekel, respectively. Foreign currency transaction gains and losses are recorded on the consolidated statements of operations and were immaterial for the years ended December 31, 2024, 2023 and 2022.

Income Taxes

We use the liability method of accounting for income taxes. Under this method, deferred tax assets and liabilities are determined based on the difference between the financial reporting and the tax reporting basis of assets and liabilities and are measured using the enacted tax rates and laws that are expected to be in effect when the differences are expected to reverse. We provide a valuation allowance against deferred tax assets unless, based upon the available evidence, it is more likely than not that the deferred tax assets will be realized. We have evaluated available evidence and concluded that we may not realize the benefit of our deferred tax assets; therefore, a valuation allowance has been established for the full amount of the net deferred tax assets. We recognize interest and/or penalties related to income tax matters in income tax expense. Our state tax provision pertains to income generated by our KSC entity. Our foreign tax provision pertains to foreign income taxes due by our German and Israel subsidiaries, both of which operate on a cost-plus profit margin basis.

Net Loss Per Share

Basic net loss per common share is calculated using the two-class method by dividing the net loss allocated to common shares by the weighted-average number of common shares outstanding for the period. Diluted net loss per common share is calculated by adjusting net loss to remove the effects from potential dilutive common shares and dividing this adjusted amount by the weighted average number of common shares and potential dilutive common shares outstanding for the period. Potential dilutive common shares are not included if their effect is anti-dilutive.

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As discussed further in Note 10, “Long-Term Obligations”, we have the option to settle the conversion obligation for our 3.00% unsecured convertible senior notes due 2025 (the “2025 Notes”) in cash, shares or any combination of the two. There was no impact of the 2025 Notes on the calculation of dilutive loss per common share during the years ended December 31, 2023 and 2022 because they were anti-dilutive in these periods. The table below describes the impact of the 2025 Notes on the calculation of dilutive loss per common share during the year ended December 31, 2024.

As discussed further in Note 10, “Long-Term Obligations”, we have the option to settle the conversion obligation for our 6.00% secured convertible senior notes due 2029 (the “2029 Notes”) in cash, shares or any combination of the two. The 2029 Notes were issued in May 2024 and did not impact the calculation of dilutive loss per common share during the year ended December 31, 2024 because they were anti-dilutive in this period.

As discussed further in Note 11, “Common Share Warrants”, warrants to purchase up to 55,563,775 shares of our common stock were outstanding as of December 31, 2024. These warrants are not included in the calculation of basic net loss per share because the warrant holders do not have an obligation to share in our losses. There was no impact of these warrants on the calculation of dilutive loss per common share during the years ended December 31, 2024, 2023 and 2022 because they were anti-dilutive in these periods.

The following is a reconciliation of the numerator and denominator used to calculate diluted net loss per common share for the year ended December 31, 2024 (in thousands except per share amounts):

For the Year Ended December 31, 2024

Add back interest expense on the 2025 Notes 2,736

Add back gain on extinguishment of debt (44,702 )

Numerator for diluted net loss per common share (A) $ (118,388 )

Weighted-average number of common shares outstanding 121,863

Dilutive effect of 2025 Notes calculated using the if-converted method 4,946

Denominator for diluted net loss per common share (B) 126,809

Diluted net loss per common share (= A / B) $ (0.93 )

The following potentially dilutive securities were excluded from the calculation of diluted net loss per share due to their anti-dilutive effect under the treasury method (in thousands):

As of December 31,

Comprehensive Loss

Comprehensive loss consists of net loss and certain changes in stockholders' deficit that are excluded from net loss, which currently consists of unrealized gains and losses on investments and foreign currency translation adjustments.

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3. Product Revenue

To date, our only source of product revenue has been from the U.S. sales of XPOVIO. The following table summarizes activity in each of the product revenue allowance and reserve categories (in thousands):

Discounts andChargebacks Fees, Rebates,and OtherIncentives Returns Total

Discounts and chargebacks are recorded as reductions of accounts receivable, and returns, fees, rebates, and other incentives are recorded as a component of accrued expenses and other liabilities.

As of December 31, 2024 and 2023, net product revenue of $27.8 million and $17.8 million, respectively, was included in accounts receivable, net.

4. Inventory

Prior to regulatory approval, we expense costs relating to the production of inventory as research and development expenses in the period incurred. We capitalize the costs incurred to manufacture our products after regulatory approval when, based on our judgment, future commercialization is considered probable and the future economic benefit is expected to be realized. We value our inventories at the lower of cost or estimated net realizable value. We determine the cost of our inventories, which includes amounts related to materials and manufacturing overhead, on a first-in, first-out basis. Raw materials and work in process includes all inventory costs prior to packaging and labelling, including raw materials, active pharmaceutical ingredient, and drug product. Finished goods include packaged and labelled products.

Raw materials and work in process that may be used for either research and development or commercial sale are classified as inventory until the material is consumed or otherwise allocated for research and development. If the material is intended to be used for research and development, it is expensed as research and development once that determination is made.

We assess the recoverability of our inventory each reporting period and write-down any inventory that has become obsolete, that has a cost basis in excess of its estimated realizable value, or that is not expected to be sold or otherwise consumed before expiry. Inventory write-downs are recorded as cost of sales in the period the impairment is identified.

Cost of sales includes the cost of producing and distributing inventories related to sales of XPOVIO in the U.S. and sales of selinexor to our partners who commercialize our products outside of the U.S. Cost of sales is recognized in the period the related sales occur and includes compensation expense for employees involved with production and distribution, freight, and indirect overhead costs, as well as third-party royalties payable on net product revenue. Cost of sales may also include excess or obsolete inventory adjustment charges, abnormal costs, unabsorbed manufacturing and overhead costs, and manufacturing variances.

The following table presents our inventory (in thousands), all of which was related to XPOVIO:

As of December 31,

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5. License Agreements

The following license agreements affected the consolidated financial statements during the years ended December 31, 2024, 2023 and 2022:

Antengene License Agreement

In May 2020, we entered into an amendment to our May 2018 license agreement (the “Original Antengene Agreement” and, as amended, the “Amended Antengene Agreement”) with Antengene Therapeutics Limited, a corporation organized and existing under the laws of Hong Kong (“Antengene”) and a subsidiary of Antengene Corporation Co. Ltd., a corporation organized and existing under the laws of the People’s Republic of China, pursuant to which we expanded the territory licensed to Antengene in the Original Antengene Agreement for the exclusive development and commercialization rights of selinexor, eltanexor and KPT-9274, each for the diagnosis, treatment and/or prevention of all human oncology indications, as well as verdinexor for the diagnosis, treatment and/or prevention of certain human non-oncology indications (“Antengene Licensed Compounds”).

Under the terms of the Amended Antengene Agreement, Antengene has the exclusive development and commercialization rights for the Antengene Licensed Compounds in mainland China, Taiwan, Hong Kong, Macau, South Korea, Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, Philippines, Singapore, Thailand, Vietnam, Australia and New Zealand (the “Antengene Territory”). Under the terms of the Original Antengene Agreement, we received an upfront cash payment of $11.7 million in 2018 and in June 2020 we received a one-time upfront cash payment of $11.7 million in connection with the Amended Antengene Agreement. We are also entitled to future milestone payments from Antengene if certain development, regulatory and commercialization goals are achieved. Finally, we are also eligible to receive tiered double-digit royalties based on future net sales of selinexor and eltanexor, and tiered single- to double-digit royalties based on future net sales of verdinexor and KPT-9274 in the Antengene Territory. In addition, upon completion of the manufacturing technology transfer plan, we will grant to Antengene non-exclusive rights to manufacture the Antengene Licensed Compounds solely for their development and commercialization in the Antengene Territory.

As part of the Amended Antengene Agreement, Antengene also has the right to participate in global clinical studies of the Antengene Licensed Compounds and will bear the cost and expense for patients enrolled in such global clinical studies in the Antengene Territory. Antengene is responsible for seeking regulatory and marketing approvals for the Antengene Licensed Compounds in the Antengene Territory, as well as any development of the products necessary to obtain such approvals. Antengene is also responsible for the commercialization of the Antengene Licensed Compounds in the Antengene Territory at its own cost and expense. Until Antengene manufactures its own drug supply, we will furnish clinical and commercial supplies to Antengene pursuant to supply agreements between us and Antengene, the costs of which will be borne by Antengene.

The Amended Antengene Agreement will continue in effect on a product-by-product, country-by-country basis until the later of the tenth anniversary of the first commercial sale of the applicable product in such country or the expiration of specified patent protection and regulatory exclusivity periods for the applicable product in such country. However, the Amended Antengene Agreement may be terminated earlier by (i) either party for breach of the Amended Antengene Agreement by the other party or in the event of the insolvency or bankruptcy of the other party, (ii) Antengene on a product-by-product basis for certain safety reasons or on a product-by-product, country-by-country basis for any reason with 180 days prior notice or (iii) us in the event Antengene challenges or assists with a challenge to certain of our patent rights.

We identified the following performance obligations in the Amended Antengene Agreement: exclusive licenses, initial data transfers, and a stand-ready obligation to provide initial clinical supply for each of the Antengene Licensed Compounds. We also identified as performance obligations the following customer options for each of the Antengene Licensed Compounds that were offered at a significant and incremental discount and represent material rights: (i) the material right for additional data transfers; (ii) the material right for additional clinical supply and related substance supply; (iii) the material right for manufacturing technology transfers and licenses; and (iv) the material right for the option for a backup compound, which represents Antengene’s option to select a replacement compound in the event it elects to discontinue the development of the Antengene Licensed Compounds. All of the performance obligations that received an allocation of the initial transaction price of $11.7 million were fully satisfied as of December 31, 2021.

All development and regulatory milestones, which represent variable consideration, will be evaluated each reporting period and included in the transaction price if the milestone is considered likely of achievement and if it is probable that a significant revenue reversal will not occur in future periods. Milestones included in the transaction price will be fully recognized in revenue in the same reporting period because all performance obligations that received an allocation of the transaction price were fully satisfied as December 31, 2021.

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Any consideration related to sales-based milestones, as well as royalties on net sales upon commercialization of XPOVIO by Antengene, are recognized when the related sales occur, as they were determined to relate predominantly to the intellectual property licenses granted to Antengene.

Menarini License Agreement

In December 2021, we entered into a license agreement (the “Original Menarini Agreement”) with Berlin-Chemie AG, an affiliate of the Menarini Group (“Menarini”), pursuant to which we granted Menarini a non-exclusive license to develop, and an exclusive license to commercialize, products containing selinexor (the “Product”), for all human oncology indications in the European Economic Area, United Kingdom, Switzerland, Armenia, Azerbaijan, Belarus, Kazakhstan, Kyrgyzstan, Moldova, Russia, Tajikistan, Turkmenistan, Uzbekistan, Ukraine, Turkey, Mexico, all Central America countries and all South America countries (collectively, the “Menarini Territory”). In March 2023, the Original Menarini Agreement was amended (the “Amended Menarini Agreement”) to expand the Menarini Territory to include all countries in the continent of Africa and Saudi Arabia, United Arab Emirates, Kuwait, Oman, Qatar, Bahrain, Lebanon, Jordan, Iraq, and Yemen (together with the Menarini Territory, the “Expanded Menarini Territory”). In addition, we granted to Menarini a non-exclusive license to package and label the Product in or outside of the Expanded Menarini Territory for all human oncology indications solely to enable Menarini to commercialize the Product within the Expanded Menarini Territory.

Under the terms of the Amended Menarini Agreement, we will use commercially reasonable efforts to develop the Product, transfer any marketing approval or authorization with respect to the Product in the Expanded Menarini Territory to Menarini and to complete any post-marketing approval or authorization studies required by a regulatory authority as a condition of maintaining the approval in any country in the Expanded Menarini Territory. Menarini is obligated to use commercially reasonable efforts to apply for and obtain marketing approval or authorization of the Product, and to obtain price or reimbursement approval for the Product after approval of the relevant marketing approval or authorization, in each country of the Expanded Menarini Territory in each indication for which we have conducted a registrational clinical trial. Menarini is also obligated to use commercially reasonable efforts at its sole cost and expense to launch and commercialize the Product in each country of the Expanded Menarini Territory in each indication for which we have conducted a registrational clinical trial.

We received an upfront cash payment of $75.0 million in December 2021 under the Original Menarini Agreement and $3.5 million in April 2023 upon execution of the Amended Menarini Agreement. In addition, we are entitled to receive additional milestone payments from Menarini if certain development and sales performance milestones are achieved. We are further eligible to receive tiered royalties ranging from the mid-teens to mid-twenties based on future net sales of the Product in the Expanded Menarini Territory. The payments owed by Menarini to us are subject to reduction in specified circumstances. Menarini will reimburse us for 25% of all expenses we incur for the development of the Product during 2022 through 2025, provided that such reimbursements shall not exceed $15.0 million per calendar year. These amounts represent variable consideration and will be recognized as earned.

The Amended Menarini Agreement will continue in effect on a country-by-country basis until the last to occur among: (i) the fifteenth anniversary of the first commercial sale of the Product in the applicable country, (ii) the expiration of the last-to-expire of the licensed patent rights in the applicable country or (iii) the expiration of any regulatory exclusivity protection covering the Product in such country. However, the Amended Menarini Agreement may be terminated earlier by either party for (i) an uncured material breach of the Amended Menarini Agreement by the other party (A) on a country-by-country basis with respect to the country to which the breach does not affect the Amended Menarini Agreement as a whole or (B) in its entirety if the breach affects the Amended Menarini Agreement as a whole, or (ii) in the event of the insolvency or bankruptcy of the other party. We may also terminate the Amended Menarini Agreement for certain patent challenges by Menarini.

We assessed this arrangement and concluded that the contract counterparty, Menarini, is a customer. We identified the following material promises in the arrangement: the granting of a non-exclusive license to develop, and an exclusive license to commercialize the Product, as well as the initial transfer of know-how and information to Menarini. The Amended Menarini Agreement provides that we will supply to Menarini, and Menarini will purchase from us, all required quantities of Product for the Expanded Menarini Territory in accordance with a supply agreement separately entered into by and between us and Menarini in 2022 (the “Supply Agreement”). We determined that the promise of the Supply Agreement was not a performance obligation at the outset of the arrangement as the rate charged for the Product was not at a significant and incremental discount and therefore did not represent a material right. We then determined that the granting of the license and the initial transfer of know-how were not distinct from one another and must be combined as a performance obligation (the “Combined Performance Obligation”). Based on these determinations, we identified one distinct performance obligation at the inception of the contract: the Combined Performance Obligation. We further determined that the up-front payment of $75.0 million constituted the entirety of the consideration included in the transaction price at contract inception, which was allocated to the Combined Performance Obligation. The Combined Performance Obligation was fully satisfied as of December 31, 2021.

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All development and regulatory milestones, which represent variable consideration, will be evaluated each reporting period and included in the transaction price if the milestone is considered likely of achievement and if it is probable that a significant revenue reversal will not occur in future periods. Milestones included in the transaction price will be fully recognized in revenue in the same reporting period because the Combined Performance Obligation was fully satisfied as of December 31, 2021.

Any consideration related to sales-based milestones, as well as royalties on net sales upon commercialization by Menarini, are recognized when the related sales occur, as they were determined to relate predominantly to the intellectual property licenses granted to Menarini.

Summary of License and Other Revenue

The following table presents information about our license and other revenue (in thousands):

For the YearsEnded December 31,

During the year ended December 31, 2024, we recognized (i) $15.0 million of revenue for the reimbursement of development-related expenses, $10.0 million of milestone revenue, $2.2 million of royalty revenue, and $0.8 million of other reimbursement revenue from Menarini; (ii) $1.7 million of royalty revenue from Antengene; and (iii) $2.0 million of milestone-related revenue, $0.4 million of royalty revenue, and $0.3 million of other reimbursement revenue from our other partners.

During the year ended December 31, 2023, we recognized (i) $15.0 million of revenue for the reimbursement of development related expenses, $4.0 million of milestone-related revenue, $3.5 million of license-related revenue, $1.1 million of royalty revenue, and $0.8 million of other reimbursement revenue from Menarini; (ii) $1.5 million of royalty revenue, and $1.2 million of other reimbursement revenue from Antengene; and (iii) $3.4 million of license-related revenue, $2.5 million of milestone-related revenue, $0.5 million of royalty revenue, and $0.5 million of other reimbursement revenue from our other partners.

During the year ended December 31, 2022, we recognized (i) $15.0 million of revenue for the reimbursement of development related expenses, $0.3 million of royalty revenue, and $0.4 million of other reimbursement revenue from Menarini; (ii) $7.8 million of milestone-related revenue, $3.8 million of royalty revenue, and $1.8 million of other reimbursement revenue from Antengene; and (iii) $5.2 million of royalty revenue and $2.3 million of milestone-related revenue from our other partners.

License and other revenue of $2.9 million and $9.1 million were included in accounts receivable, net as of December 31, 2024 and 2023, respectively. No license and other revenue was included in other current assets as of December 31, 2024. License and other revenue of $1.0 million was included in other current assets as of December 31, 2023.

6. Fair Value Measurements

Financial instruments, including cash, cash equivalents, accounts receivable, net, other current assets, other assets, restricted cash, accounts payable, and accrued expenses, are presented at amounts that approximate fair value as of December 31, 2024 and 2023.

Items classified as Level 2 consist of corporate debt securities, commercial paper, and U.S. government and agency securities. We estimate the fair values of these marketable securities by taking into consideration valuations obtained from third-party pricing sources. These pricing sources utilize industry standard valuation models, including both income and market-based approaches, for which all significant inputs are observable, either directly or indirectly, to estimate fair value. These inputs include market pricing based on real-time trade data for the same or similar securities, issuer credit spreads, benchmark yields, and other observable inputs. We validate the prices provided by our third-party pricing sources by understanding the models used, obtaining market values from other pricing sources and analyzing pricing data in certain instances.

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The following tables present information about our financial assets that have been measured at fair value and indicate the fair value hierarchy of the valuation inputs utilized to determine such fair value (in thousands):

Cash equivalents:

Investments:

U.S. government and agency securities 3,979 — 3,979 —

Cash equivalents:

U.S. government and agency securities 1,998 — 1,998 —

Investments:

U.S. government and agency securities 47,507 — 47,507 —

In certain cases where there is limited activity or less transparency around inputs to valuation, the related assets or liabilities are classified as Level 3. The following liabilities are measured at fair value at the end of each reporting period, with changes in fair value recognized as a component of other income (expense), net on our consolidated statements of operations. See Note 10, “Long-Term Obligations”, to our consolidated financial statements for further discussion of the following Level 3 liabilities:

(1)

The embedded derivative liability (the “HCRx Derivative”) associated with a Revenue Interest Financing Agreement (the “Revenue Interest Agreement”) we entered into with HCRx in September 2019 and as amended in June 2021, August 2023 and May 2024 (as amended, the “Amended Revenue Interest Agreement”) is included as a component of the deferred royalty obligation on our consolidated balance sheets. The valuation method for the HCRx Derivative incorporates certain unobservable Level 3 key inputs including: (i) the probability-weighted net sales of XPOVIO and any of our other future products, including worldwide net product sales, upfront payments, milestones and royalties; (ii) our risk-adjusted discount rate; and (iii) the probability of a change in control occurring during the term of the instrument. The HCRx Derivative was deemed to have a de-minimus value as of December 31, 2024 primarily due to a $56.2 million decrease in the deferred royalty obligation during the year ended December 31, 2024.

(2)

The embedded derivative liabilities (the “2029 Notes Derivatives”) associated with the 2029 Notes are included as a component of the 2029 Notes on our consolidated balance sheets. The valuation method for the 2029 Notes Derivatives incorporates certain unobservable Level 3 key inputs including: (i) the volatility of our common stock price and (ii) our estimated credit spread.

(3)

The warrants to purchase up to 45.8 million shares of our common stock issued in May 2024 (the “May 2024 Warrants”) are classified as a long-term liability on our consolidated balance sheets. The valuation method for the May 2024 Warrants incorporates certain unobservable Level 3 key inputs including: (i) the volatility of our common stock price and (ii) an estimate of when the May 2024 Warrants will be exercised based on an option pricing model.

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The following table sets forth a summary of the changes in the estimated fair value of the liabilities described above, which are all classified as Level 3 (in thousands):

HCRx Derivative 2029 Notes Derivatives May 2024 Warrants

See Note 10, “Long-Term Obligations”, to our consolidated financial statements for further discussion on the fair value of our debt instruments.

7. Investments

The following tables summarize our investments in debt securities, classified as available-for-sale (in thousands):

AmortizedCost TotalUnrealizedGains TotalUnrealizedLosses Aggregate Fair Value

U.S. government and agency securities 3,978 1 — 3,979

AmortizedCost TotalUnrealizedGains TotalUnrealizedLosses Aggregate Fair Value

As of December 31, 2024 and 2023, we held 5 and 41 debt securities, respectively, that were in an unrealized loss position. The unrealized losses as of December 31, 2024 and 2023 were attributable to changes in interest rates and do not represent credit losses. We do not intend to sell the investments before recovery of their amortized cost bases, which may be at maturity. All our investments mature within two years from December 31, 2024. The following tables summarize our debt securities in an unrealized loss position for which an allowance for credit losses has not been recorded, aggregated by major security type and length of time in a continuous unrealized loss position (in thousands):

Less than 12 Months 12 Months or Longer Total

Corporate debt securities $ 4,456 $ (2 ) $ — $ — $ 4,456 $ (2 )

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Less than 12 Months 12 Months or Longer Total

8. Stockholders’ Equity

Authorized Common Shares

On May 24, 2023, our stockholders approved an amendment to our Restated Certificate of Incorporation, as amended, to increase the number of authorized shares of our common stock from 200,000,000 shares to 400,000,000 shares.

On January 30, 2025, our stockholders approved an amendment to our Restated Certificate of Incorporation, as amended, to increase the number of authorized shares of our capital stock from 405,000,000 to 805,000,000 and the number of authorized shares of our common stock from 400,000,000 shares to 800,000,000 shares. In addition, on January 30, 2025, our stockholders approved an amendment to our Restated Certificate of Incorporation, as amended, to effect a reverse stock split of our issued shares of common stock at a ratio within the range of not less than 1-for-5 and not greater than 1-for-15, and a proportionate reduction in the number of authorized shares of common stock, with the exact ratio within such range and the implementation and timing of such reverse stock split to be determined at the sole discretion of our Board of Directors, without further approval or authorization of our stockholders.

Private Placement Offering

On December 5, 2022, we entered into a securities purchase agreement with certain institutional investors pursuant to which we issued and sold, in a private placement offering of securities, an aggregate of 31,791,908 shares of common stock. We received aggregate net proceeds of approximately $154.7 million.

Open Market Sale Agreement

On February 17, 2023, we entered into an Open Market Sale Agreement (the “2023 Open Market Sale Agreement”) with Jefferies LLC, as agent (“Jefferies”). Under the 2023 Open Market Sale Agreement, we may issue and sell shares of our common stock having an aggregate offering price of up to $100.0 million (the “Shares”) from time to time through Jefferies (the “2023 Open Market Offering”). Upon entry into the 2023 Open Market Sale Agreement, we terminated our previous Open Market Sale Agreement with Jefferies, as agent, which we had entered into in August 2018 (the “2018 Open Market Sale Agreement”), pursuant to which we could issue and sell shares of our common stock having an aggregate offering price of up to $175.0 million (the “Open Market Shares”).

Under the 2023 Open Market Sale Agreement, Jefferies may sell the Shares by methods deemed to be an “at the market offering” as defined in Rule 415(a)(4) promulgated under the Securities Act of 1933, as amended (the “Securities Act”). We may sell the Shares in amounts and at times to be determined by us from time to time subject to the terms and conditions of the 2023 Open Market Sale Agreement, but we have no obligation to sell any of the Shares in the 2023 Open Market Offering.

We or Jefferies may suspend or terminate the offering of Shares upon notice to the other party and subject to other conditions. We have agreed to pay Jefferies commissions for its services in acting as agent in the sale of the Shares in the amount of up to 3.0% of gross proceeds from the sale of the Shares pursuant to the 2023 Open Market Sale Agreement. We have also agreed to provide Jefferies with customary indemnification and contribution rights.

During the year ended December 31, 2022, we sold an aggregate of 3,991,652 Open Market Shares under the 2018 Open Market Sale Agreement, for net proceeds of $35.1 million. We did not sell any Open Market Shares under the 2018 Open Market Sale Agreement nor any Shares under the 2023 Open Market Sale Agreement during the years ended December 31, 2024 and 2023. As of December 30, 2024, $100.0 million of Shares was available for issuance and sale under the 2023 Open Market Sale Agreement.

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9. Stock-based Compensation

On May 19, 2022, our stockholders approved the 2022 Equity Incentive Plan (the “2022 Plan”), succeeding our 2013 Stock Incentive Plan (the “2013 Plan”), which has expired and under which no further grants may be made. The 2022 Plan provides for the grant of incentive stock options, non-statutory stock options, stock appreciation rights, restricted stock awards, RSU awards and other stock-based awards. On May 24, 2023 and May 29, 2024, our stockholders approved an amendment to the 2022 Plan to increase the number of shares of our common stock available for issuance under the 2022 Plan by 5,000,000 and 6,000,000 shares, respectively. As of December 31, 2024, there were 8,070,510 shares available for future grants under the 2022 Plan.

Under the terms of the 2022 Plan and the 2013 Plan, we granted stock options, RSUs, and PSUs to our employees, officers, directors, consultants and advisors. Stock options have a ten-year term and an exercise price equal to the fair market value of a share of our common stock on the grant date. Stock options and RSUs vest over a period of one to four years. PSUs will vest if certain performance goals are achieved over a certain performance period. Certain portions of certain PSU awards vest based on continuous service to the Company throughout the performance period even if the performance goal is not achieved.

During 2024, 2023, and 2022, we also granted stock options and RSUs through inducement grants outside of our stockholder approved equity compensation plans as permitted under the Nasdaq Stock Market listing rules to certain employees to induce them to accept employment with us (collectively, “Inducement Awards”). In February 2022, our Board approved the 2022 Inducement Stock Incentive Plan (the “2022 Inducement Plan”) under which 850,000 shares of common stock were initially reserved for issuance for inducement awards to be granted to newly hired full-time employees. In 2022, 2023, and 2024, the Board increased the number of shares reserved for issuance under the 2022 Inducement Plan by 850,000,1,200,000, and 1,000,000, respectively. We assessed the terms of these Inducement Awards and determined there was no possibility that we would have to settle these awards in cash and therefore, equity accounting was applied. As of December 31, 2024, there were 1,523,535 shares available for future grants under the 2022 Inducement Plan.

As of December 31, 2024, we had 28,745,131 shares reserved for issuance, which includes shares available for future grants and outstanding stock options, RSUs and PSUs under the 2013 Plan, 2022 Plan, and Inducement Awards (including the Inducement Awards granted under the 2022 Inducement Plan).

Stock-based Compensation Expense

Total stock-based compensation expense recognized was as follows (in thousands):

For the Years Ended December 31,

The total stock-based compensation expense recognized by award type was as follows (in thousands):

For the Years Ended December 31,

We agreed with our financial advisor to settle our fee for services provided in connection with the May 2024 refinancing transactions described in Note 10, “Long-Term Obligations”, through the private placement of 6,872,027 shares of our common stock, resulting in $6.9 million being capitalized to our consolidated balance sheet as a debt issuance cost and $0.8 million being expensed to selling, general and administrative expense as stock-based compensation expense on our consolidated statements of operations during the year ended December 31, 2024.

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During the year ended December 31, 2022, we accelerated the vesting and extended the exercise date of certain stock-based awards granted to our former Chief Executive Officer and former Chief Scientific Officer in connection with their departure from the Company in May 2022. These modifications resulted in the recognition of incremental stock-based compensation expense of $7.4 million for the year ended December 31, 2022.

Stock Options

The following table summarizes stock option activity related to the 2013 Plan, 2022 Plan, and Inducement Awards (including the stock option Inducement Awards granted under the 2022 Inducement Plan):

There were no stock options exercised for the year ended December 31, 2024. The total intrinsic value of stock options exercised for the years ended December 31, 2023 and 2022 was less than $0.1 million and $0.3 million, respectively.

The fair value of each stock option granted is estimated on the date of grant using the Black-Scholes option-pricing model. The following table summarizes the assumptions used in calculating the fair value of the stock option awards:

For the Years Ended December 31,

Dividend —% —% —%

We use the simplified method to calculate the expected term as our historical exercise data does not provide a reasonable basis upon which to estimate the expected term. The expected term is applied to the stock option grant group as a whole, as we do not expect substantially different exercise or post-vesting termination behavior among our employee population. Our expected stock price volatility assumption is based on the historical volatility of our publicly traded stock. The risk-free interest rate is based on a treasury instrument whose term is consistent with the expected term of the stock options. We account for forfeitures as they occur.

Using the Black-Scholes option-pricing model, the weighted-average grant date fair values of options granted during the years ended December 31, 2024, 2023 and 2022 was $0.64, $1.54 and $5.83 per share, respectively.

As of December 31, 2024, there was $2.6 million of unrecognized compensation expense related to unvested stock option awards, which is expected to be recognized over a weighted-average period of 1.1 years.

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Restricted Stock Units and Performance-Based Restricted Stock Units

The following is a summary of RSU and PSU activity for the 2013 Plan, 2022 Plan, and Inducement Awards (including RSU Inducement Awards granted under the 2022 Inducement Plan):

Number ofSharesUnderlyingRSUs and PSUs Weighted-AverageGrant DateFair Value

The total fair value of RSUs and PSUs that vested during the years ended December 31, 2024, 2023 and 2022 was $2.8 million, $2.9 million, and $8.3 million, respectively. As of December 31, 2024, there was $19.0 million of unrecognized compensation expense related to unvested RSUs and PSUs, which is expected to be recognized over a weighted-average period of 1.8 years.

Employee Stock Purchase Plan

We have an ESPP that permits eligible employees to enroll in six-month offering periods. Participants may purchase shares of our common stock, through payroll deductions, at a price equal to 85% of the fair market value of the common stock on the first or last day of the applicable offering period, whichever is lower. Purchase dates under the ESPP occur on or about May 1 and November 1 each year. In 2013, our stockholders approved an annual increase in the number of shares of common stock authorized for issuance pursuant to the ESPP to be added on the first day of each fiscal year, commencing on January 1, 2015 and ending on December 31, 2023, equal to the lesser of 484,848 shares of our common stock, 1% of the number of outstanding shares on such date, or an amount determined by the Board (the “Evergreen Provision”). On May 24, 2023, our stockholders approved an amendment and restatement of our ESPP (the “Amended & Restated ESPP”), which (i) eliminated the Evergreen Provision and (ii) increased the number of shares of common stock authorized for issuance under the ESPP by 1,500,000 shares. On May 29, 2024, our stockholders approved an amendment to the Amended & Restated ESPP to increase the number of shares of our common stock available for issuance under the Amended & Restated ESPP by 5,000,000 shares. As of December 31, 2024, 4,655,260 shares of our common stock remained available for issuance under the Amended & Restated ESPP.

During the years ended December 31, 2024, 2023 and 2022, $1.5 million, $1.1 million and $2.3 million, respectively, was withheld from employees, on an after-tax basis, in order to purchase 1,977,558, 638,182 and 508,391 shares of our common stock, respectively. As of December 31, 2024, there was $0.2 million of total unrecognized stock-based compensation expense related to the Amended & Restated ESPP. The expense is expected to be recognized over a period of four months.

The fair value of the option component of the shares purchased under the Amended & Restated ESPP was estimated using the Black-Scholes option-pricing model with the following weighted-average assumptions:

For the Years Ended December 31,

Dividend —% —% —%

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10. Long-Term Obligations

2025 Notes

In October 2018, we issued $172.5 million aggregate principal amount of the 2025 Notes in a private offering to qualified institutional buyers in reliance on Rule 144A under the Securities Act. In connection with the issuance of the 2025 Notes, we incurred $5.6 million of debt issuance costs, which was being amortized to interest expense using the effective interest method over seven years. In May 2024, we exchanged $148.0 million aggregate principal amount of our 2025 Notes for (i) $111.0 million aggregate principal amount of our 2029 Notes and (ii) the May 2024 Warrants to purchase up to 45.8 million shares of our common stock. The 2029 Notes and the May 2024 Warrants are described in more detail below. $24.5 million in aggregate principal amount of the 2025 Notes remained outstanding following completion of the May 2024 exchange transactions (the “Remaining 2025 Notes”) and as of December 31, 2024.

The Remaining 2025 Notes are senior unsecured obligations and bear interest at a rate of 3.00% per year payable semiannually in arrears on April 15 and October 15 of each year. Upon conversion, the Remaining 2025 Notes will be converted into cash, shares of our common stock, or a combination of cash and shares of our common stock, at our election. The Remaining 2025 Notes are subject to redemption at our option, in whole or in part, if the conditions described below are satisfied. Holders may require us to repurchase their Remaining 2025 Notes following a fundamental change (as defined within the indenture governing the 2025 Notes) at a cash repurchase price generally equal to the principal amount of the Remaining 2025 Notes to be repurchased, plus accrued and unpaid interest. The Remaining 2025 Notes will mature on October 15, 2025, unless earlier converted, redeemed or repurchased in accordance with their terms. Subject to satisfaction of certain conditions and during the periods described below, the Remaining 2025 Notes may be converted at an initial conversion rate of 63.0731 shares of common stock per $1,000 principal amount of the Remaining 2025 Notes (equivalent to an initial conversion price of approximately $15.85 per share of common stock).

Holders of the Remaining 2025 Notes may convert all or any portion of their Remaining 2025 Notes, in multiples of $1,000 principal amount, at their option at any time prior to the close of business on the business day immediately preceding June 15, 2025 only under the following circumstances:

(1)

during any calendar quarter, if the last reported sale price of our common stock for at least 20 trading days (whether or not consecutive) during the period of 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter is greater than or equal to 130% of the conversion price for the Remaining 2025 Notes on each applicable trading day;

(2)

during the five-business day period immediately after any five consecutive trading day period (the “Measurement Period”) in which the trading price per $1,000 principal amount of Remaining 2025 Notes for each trading day of the Measurement Period was less than 98% of the product of the last reported sale price of our common stock and the conversion rate on each such trading day;

(3)

if we call the Remaining 2025 Notes for redemption, until the close of business on the business day immediately preceding the redemption date; or

(4)

upon the occurrence of specified corporate events as described within the indenture governing the 2025 Notes.

As of December 31, 2024, none of the above circumstances had occurred and as such, the Remaining 2025 Notes could not have been converted.

We may redeem for cash all or part of the Remaining 2025 Notes at our option if the last reported sale price of our common stock equals or exceeds 130% of the conversion price then in effect for at least 20 trading days (whether or not consecutive) during any 30 consecutive trading day period ending within five trading days prior to the date on which we send any notice of redemption. The redemption price will be 100% of the principal amount of the Remaining 2025 Notes to be redeemed, plus accrued and unpaid interest, if any. In addition, calling any convertible note for redemption will constitute a make-whole fundamental change with respect to that convertible note, in which case the conversion rate applicable to the conversion of that convertible note, if it is converted in connection with the redemption, will be increased in certain circumstances. We did not redeem any of the Remaining 2025 Notes as of December 31, 2024.

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The outstanding balances of the 2025 Notes consisted of the following (in thousands):

As of December 31,

Less: unamortized debt issuance costs (74 ) (1,581 )

We determined the expected life of the 2025 Notes was equal to its seven-year term and the effective interest rate was 3.53%. As of December 31, 2024, the “if-converted value” did not exceed the remaining principal amount of the 2025 Notes. The fair value of the 2025 Notes is influenced by market interest rates, our stock price and stock price volatility, and has been classified as Level 2 within the fair value hierarchy as it uses quoted prices in active markets. The estimated fair value of the 2025 Notes as of December 31, 2024 and 2023 was $19.1 million and $87.9 million, respectively.

The following table sets forth total interest expense recognized related to the 2025 Notes (in thousands):

For the YearsEnded December 31,

Amortization of debt issuance costs 382 814 812

Future minimum payments on the Remaining 2025 Notes were as follows (in thousands):

Years ended December 31, Future MinimumPayments

Less: interest expense and unamortized debt issuance costs (810 )

Senior Secured Term Loan

On May 8, 2024, we entered into a credit and guaranty agreement (the “Credit Agreement”) with certain existing holders of the 2025 Notes and HCRx, which provides for a senior secured term loan facility of $100.0 million (the “Term Loan”). The Term Loan matures in May 2028 and bears interest at a variable rate equal to the applicable secured overnight financing rate plus 9.25%, subject to a floor of 3.00%. Principal payments under the Term Loan will begin in June 2026, and consist of quarterly cash payments in the amount of 6.25% of the aggregate principal amount of the Term Loan, with the remaining principal due when the Term Loan matures in May 2028.

We can prepay the Term Loan at any time. All repayments, including prepayments, are subject to a redemption fee of 3.00% of the principal paid. Prepayments made before May 8, 2027 are subject to a prepayment premium ranging from 3.00% to 5.00% of the principal prepaid. The prepayment premium for prepayments made before May 8, 2025 also includes the unpaid interest that would have accrued on the amount being prepaid through May 8, 2025. In addition, we are required to repay the Term Loan with proceeds from certain asset sales and condemnation events, subject, in some cases, to reinvestment rights.

All obligations under the Credit Agreement are secured on a first priority basis, subject to certain exceptions, by substantially all of our assets. The Credit Agreement contains customary covenants, including a requirement to maintain cash, cash equivalents and investments of at least $25.0 million at all times, and restrictions on indebtedness, liens, investments, fundamental changes, asset sales, licensing transactions, dividends, modifications to material agreements, payment of subordinated indebtedness, and other matters customarily restricted in such agreements. Specifically, we are prohibited from exclusively licensing, selling or otherwise disposing of U.S. rights to oncology indications of selinexor. As of December 31, 2024, we were in compliance with these covenants. If certain events of default occur, the Term Loan may be due and payable immediately. These events include the withdrawal of approval of certain indications of selinexor, payment defaults, covenant defaults, bankruptcy, cross-defaults to certain other agreements, change in control and lien priority.

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The outstanding balance of the Term Loan consisted of the following (in thousands):

Less: unamortized debt issuance costs (5,397 )

We determined the expected life of the Term Loan was equal to its four-year term and the effective interest rate is approximately 17%. The principal value of the Term Loan approximates its fair value due to the variable interest rate. In connection with the issuance of the Term Loan, we incurred $6.8 million of debt issuance costs, which are being amortized to interest expense using the effective interest method over four years. We recognized $10.8 million of interest expense related to the Term Loan during the year ended December 31, 2024, which consisted of $9.4 million of contractual interest expense and $1.4 million of debt issuance cost amortization.

Future minimum payments on the Term Loan as of December 31, 2024 were as follows (in thousands):

KPTI US Equity

KPTI · 10-K · period ended 2024-12-31

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

Item 7A. Quantitative and Qualitative Disclosures about Market Risk

Item 8. Financial Statements and Supplementary Data

Item 9A. Controls and Procedures

Item 9B. Other Information

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections

Item 10. Directors, Executive Officers and Corporate Governance

Item 11. Executive Compensation

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

Item 13. Certain Relationships and Related Transactions, and Director Independence

Item 14. Principal Accountant Fees and Services

Item 15. Exhibits and Financial Statement Schedules

Item 16. Form 10-K Summary

KPTI US Equity☆

KPTI · 10-K · period ended 2024-12-31

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

Item 7A. Quantitative and Qualitative Disclosures about Market Risk

Item 8. Financial Statements and Supplementary Data

Item 9A. Controls and Procedures

Item 9B. Other Information

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections

Item 10. Directors, Executive Officers and Corporate Governance

Item 11. Executive Compensation

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

Item 13. Certain Relationships and Related Transactions, and Director Independence

Item 14. Principal Accountant Fees and Services

Item 15. Exhibits and Financial Statement Schedules

Item 16. Form 10-K Summary

KPTI US Equity