Keros Therapeutics, Inc.

Previous wording

We are a clinical-stage biopharmaceutical company focused on developing and commercializing novel therapeutics to treat a wide range of patients with disorders that are linked to dysfunctional signaling of the transforming growth factor-beta, or TGF-ß, family of proteins. We are a leader in understanding the role of the TGF-ß family of proteins, which are master regulators of the growth, repair and maintenance of a number of tissues, including blood, bone, skeletal muscle, adipose and heart tissue. By leveraging this understanding, we have discovered and are developing protein therapeutics that have the potential to provide meaningful and potentially disease-modifying benefit to patients. One of our product candidates, cibotercept (KER-012), is being developed for the treatment of pulmonary arterial hypertension, or PAH, and for the treatment of cardiovascular disorders. Our second product candidate, KER-065, is being developed for the treatment of neuromuscular diseases. Our most advanced product candidate, elritercept (KER-050), is being developed for the treatment of low blood cell counts, or cytopenias, including anemia and thrombocytopenia, in patients with myelodysplastic syndromes, or MDS, and in patients with myelofibrosis.

Current wording

We are a clinical-stage biopharmaceutical company focused on developing and commercializing novel therapeutics to treat a wide range of patients with disorders that are linked to dysfunctional signaling of the transforming growth factor-beta, or TGF-ß, family of proteins. We are a leader in understanding the role of the TGF-ß family of proteins, which are master regulators of the growth, repair and maintenance of a number of tissues, including skeletal muscle, bone, adipose, heart tissue and blood. By leveraging this understanding, we have discovered and are developing protein therapeutics that have the potential to provide meaningful and potentially disease-modifying benefit to patients. Our lead product candidate, rinvatercept (KER-065), is being developed for the treatment of Duchenne muscular dystrophy and for the treatment of amyotrophic lateral sclerosis. Our most advanced product candidate, elritercept (KER-050), is being developed for the treatment of low blood cell counts, or cytopenias, including anemia and thrombocytopenia, in patients with myelodysplastic syndromes, or MDS, and in patients with myelofibrosis. In December 2024, we entered into an exclusive license agreement with Takeda Pharmaceuticals U.S.A., Inc., or Takeda, which became effective on January 16, 2025, to further develop, manufacture and commercialize elritercept worldwide outside of mainland China, Hong Kong and Macau.

Previous wording

In December 2022, we filed a prospectus supplement to our registration statement on Form S-3ASR with the Securities and Exchange Commission, or the SEC, for the issuance and sale, if any, of up to$250.0 million of shares of our common stock pursuant to a sales agreement with Leerink Partners LLC, or Leerink, as sales agent, which we refer to as the ATM Sales Agreement, under which we may offer and sell, from time to time, shares of our common stock, or the ATM Shares, through Leerink, which we refer to as the ATM Offering. In May 2024, we filed a new registration statement on Form S-3ASR, which we refer to as the New Shelf Registration Statement, to replace the prior shelf registration statement that was set to expire, including a base prospectus, which became effective immediately upon filing, under which we could issue an unspecified amount of shares of our common stock, preferred stock, debt securities and warrants. In June 2024, we filed a prospectus supplement to the New Shelf Registration Statement for the issuance and sale, if any, of up to an additional$350.0 million of shares of our common stock under the ATM Sales Agreement.

Current wording

In December 2022, we filed a prospectus supplement to our registration statement on Form S-3ASR with the Securities and Exchange Commission, or the SEC, for the issuance and sale, if any, of up to $250.0 million of shares of our common stock pursuant to a sales agreement with Leerink Partners LLC, or Leerink, as sales agent, which we refer to as the ATM Sales Agreement, under which we may offer and sell, from time to time, shares of our common stock, or the ATM Shares, through Leerink, which we refer to as the ATM Offering. In May 2024, we filed a new registration statement on Form S-3ASR, which we refer to as the New Shelf Registration Statement, to replace the prior shelf registration statement that was set to expire, including a base prospectus, which became effective immediately upon filing, under which we could issue an unspecified amount of shares of our common stock, preferred stock, debt securities and warrants. In June 2024, we filed a prospectus supplement to the New Shelf Registration Statement for the issuance and sale, if any, of up to an additional$350.0 million of shares of our common stock under the ATM Sales Agreement. As of the filing of our Annual Report on Form 10-K for the year ended December 31, 2024, we no longer qualified as a well-known seasoned issuer and therefore were not eligible to use the New Shelf Registration Statement as an automatic shelf registration statement, and no shares were sold during the year ended December 31, 2025.

Previous wording

Under the ATM Sales Agreement, Leerink may sell the ATM Shares by methods deemed to be an “at the market offering” as defined in Rule 415(a)(4) promulgated under the Securities Exchange Act of 1934, as amended. We may sell the ATM Shares in amounts and at times to be determined by us from time to time subject to the terms and conditions of the ATM Sales Agreement, but we have no obligation to sell any of the ATM Shares in the ATM Offering. As of December 31, 2024, we have sold a total of 4,290,096 shares of our common stock pursuant to the ATM Offering for aggregate net proceeds of approximately $228.6 million after deducting sales agent commissions and estimated offering expenses. As of December 31, 2024, we may offer and sell ATM shares at an aggregate offering price of up to the remaining $117.7 million available under the ATM Offering.

Current wording

Under the ATM Sales Agreement, Leerink may sell the ATM Shares by methods deemed to be an “at the market offering” as defined in Rule 415(a)(4) promulgated under the Securities Exchange Act of 1934, as amended. We may sell the ATM Shares in amounts and at times to be determined by us from time to time subject to the terms and conditions of the ATM Sales Agreement, but we have no obligation to sell any of the ATM Shares in the ATM Offering. As of December 31, 2025, we have sold a total of 4,290,096 shares of our common stock pursuant to the ATM Offering for aggregate net proceeds of approximately $228.6 million after deducting sales agent commissions and estimated offering expenses. As of December 31, 2025, we may not offer and sell any ATM shares.

Previous wording

We have incurred recurring operating losses since inception in 2015. Our ability to generate product revenue sufficient to achieve profitability will depend on the successful development and commercialization of one or more of our product candidates. Our net loss was $187.4 million, $153.0 million, and $104.7 million for the years ended December 31, 2024, 2023, and 2022, respectively. As of December 31, 2024, we had an accumulated deficit of $568.8 million. We expect to continue to generate operating losses and negative operating cash flows for the foreseeable future in connection with our ongoing activities.

Current wording

Since our inception, we have incurred recurring operating losses each fiscal year through December 31, 2024. Our ability to generate product revenue sufficient to achieve profitability will depend on the successful development and commercialization of one or more of our product candidates. Our net income, which was primarily driven by revenue related to the Takeda Agreement, was $87.0 million for the year ended December 31, 2025 compared to a net loss of $187.4 million for the year ended December 31, 2024. As of December 31, 2025, we had an accumulated deficit of $481.8 million. We expect to continue to generate operating losses and negative operating cash flows for the foreseeable future in connection with our ongoing activities.

Previous wording

As of December 31, 2024, we had cash and cash equivalents of $559.9 million. Based on our current operating assumptions, we expect that our existing cash and cash equivalents as of December 31, 2024, together with the $200 million upfront payment pursuant to the license agreement with Takeda Pharmaceuticals U.S.A., Inc., or Takeda, which we received in February 2025, will enable us to fund our operating expenses and capital expenditure requirements into 2029. See “—Liquidity and Capital Resources.”

Current wording

As of December 31, 2025, we had cash and cash equivalents of $287.4 million. Based on our current operating assumptions, we expect that our existing cash and cash equivalents as of December 31, 2025 will enable us to fund our operating expenses and capital expenditure requirements into the first half of 2028. See “—Liquidity and Capital Resources.”

Previous wording

While recent trends towards rising inflation have eased, prices continue to rise, which may also materially affect our business and corresponding financial position and cash flows. Inflationary factors, such as increases in the cost of materials and supplies relating to our preclinical studies, clinical trials, interest rates and overhead costs may adversely affect our operating results. Rising interest rates also present a recent challenge impacting the U.S. economy and could make it more difficult for us to obtain traditional financing on acceptable terms, if at all, in the future. Additionally, the general consensus among economists suggests that we should expect a higher recession risk to continue over the next year, which, together with the foregoing, could result in further economic uncertainty and volatility in the capital markets in the near term, and could negatively affect our operations. Furthermore, such economic conditions have produced downward pressure on share prices. Although we do not believe that inflation or higher interest rates have had a material impact on our financial position or results of operations to date, we may experience increases in the near future (especially if inflation rates rise more quickly) on our operating costs, including our labor costs and research and development costs, due to supply chain constraints, consequences associated with public health crises and global geopolitical tensions, such as the ongoing war between Russia and Ukraine and the war in Israel, worsening global macroeconomic conditions, including as a result of bank failures, and employee availability and wage increases, which may result in additional stress on our working capital resources.

Current wording

While recent trends towards rising inflation have eased, prices continue to rise, which may also materially affect our business and corresponding financial position and cash flows. Inflationary factors, such as increases in the cost of materials and supplies relating to our preclinical studies, clinical trials, interest rates and overhead costs may adversely affect our operating results. Rising interest rates and implementation of tariffs also present a recent challenge impacting the U.S. economy and could make it more difficult for us to obtain traditional financing on acceptable terms, if at all, in the future. Additionally, the general consensus among economists suggests that we should expect a higher recession risk to continue over the next year due in part to ongoing tariff and trade uncertainties, which, together with the foregoing, could result in further economic uncertainty and volatility in the capital markets in the near term, and could negatively affect our operations. Furthermore, such economic conditions have produced downward pressure on share prices. Although we do not believe that inflation, higher interest rates or tariffs have had a material impact on our financial position or results of operations to date, we may experience increases in the near future (especially if inflation rates rise more quickly) on our operating costs, including our labor costs and research and development costs, due to supply chain constraints, consequences associated with public health crises and global geopolitical tensions, such as the ongoing war between Russia and Ukraine and the war in the Middle East, worsening global macroeconomic conditions, including as a result of bank failures, and employee availability and wage increases, which may result in additional stress on our working capital resources.

Previous wording

Pursuant to the terms of the Hansoh Agreement, we received a net $18.0 million upfront payment in January 2022. In addition to the upfront payment and development milestones achieved to date, we are entitled to receive up to an aggregate of (i) $23.5 million upon the achievement of specified development milestones and (ii)$144.0 million upon the achievement of specified net sales thresholds for all licensed products in the Hansoh Territory. If a licensed product is approved for marketing in the Hansoh Territory, we will be entitled to receive royalty payments based on a tiered percentage of annual net sales in each region within the Hansoh Territory, with such percentage ranging from the low double digit to high teens, subject to specified potential royalty reductions. We recognized $3.0 million as revenue and $0.3 million in withholding tax upon the achievement of a development milestone related to the Hansoh Agreement on our consolidated statement of operations for the year ended December 31, 2024, and a receivable, net of withholding tax, on our consolidated balance sheet as of December 31, 2024.

Current wording

Pursuant to the terms of the Hansoh Agreement, we received a net $18.0 million upfront payment in January 2022. We recognized $3.0 million as revenue and $0.3 million in withholding tax upon the achievement of a development milestone related to the Hansoh Agreement on our consolidated statement of operations for the year ended December 31, 2024, and a receivable, net of withholding tax, on our consolidated balance sheet as of December 31, 2024. In addition to the upfront payment and development milestones achieved to date, we are entitled to receive up to an aggregate of (i) $23.5 million upon the achievement of specified development milestones and (ii) $144.0 million upon the achievement of specified net sales thresholds for all licensed products in the Hansoh Territory. If a licensed product is approved for marketing in the Hansoh Territory, we will be entitled to receive royalty payments based on a tiered percentage of annual net sales in each region within the Hansoh Territory, with such percentage ranging from the low double digit to high teens, subject to specified potential royalty reductions. No milestones were achieved during the year ended December 31, 2025.

Previous wording

Effective in June 2023, in connection with the Hansoh Agreement, we entered into a manufacturing technology transfer agreement, or the Tech Transfer Agreement, with Hansoh. The Tech Transfer Agreement governs the transfer to Hansoh of all documents and information required to complete the manufacturing technology transfer. Under the Tech Transfer Agreement, Hansoh is obligated to make certain payments to us, at the rates set forth in the Tech Transfer Agreement, as manufacturing technology transfer services are provided over the term of the Tech Transfer Agreement. We recognized $96.1 thousand and $150.8 thousand of service and other revenue for the years ended December 31, 2024 and 2023, respectively.

Current wording

Effective in June 2023, in connection with the Hansoh Agreement, we entered into a manufacturing technology transfer agreement, or the Tech Transfer Agreement, with Hansoh. The Tech Transfer Agreement governs the transfer to Hansoh of all documents and information required to complete the manufacturing technology transfer. Under the Tech Transfer Agreement, Hansoh is obligated to make certain payments to us, at the rates set forth in the Tech Transfer Agreement, as manufacturing technology transfer services are provided over the term of the Tech Transfer Agreement. We recognized $0.1 million and $0.1 million of service and other revenue for the years ended December 31, 2025 and 2024, respectively.

Previous wording

Effective in February 2024, in connection with the Hansoh Agreement, we entered into a clinical product supply agreement with Hansoh, or the Supply Agreement. We recognized $421.1 thousand of other revenue for the year ended December 31, 2024.

Current wording

Effective in February 2024, in connection with the Hansoh Agreement, we entered into a clinical product supply agreement with Hansoh, or the Supply Agreement. We recognized $0.1 million and $0.4 million of other revenue for the years ended December 31, 2025 and 2024, respectively.

Previous wording

Pursuant to the terms of the Takeda Agreement, we received a $200.0 million upfront payment in February 2025. In addition to the upfront payment, we are entitled to receive up to an aggregate of (i) $370.0 million upon the achievement of specified development and commercial milestones and (ii) $740.0 million upon the achievement of specified sales milestones. If a licensed product is approved for marketing in the Takeda Territory, we will be entitled to receive royalty payments based on tiered increments of annual net sales in the Takeda Territory, with such percentage ranging from the low double-digits to high teens, subject to specified potential royalty reductions.

Current wording

Pursuant to the terms of the Takeda Agreement, we received a $200.0 million upfront payment in February 2025. In July 2025, we announced that the first patient was dosed in the Phase 3 RENEW clinical trial of elritercept, which triggered a $10.0 million milestone payment to us under the Takeda Agreement. We received the $10.0 million payment for the achievement of this development milestone in August 2025. In addition to the upfront payment and milestone payment, we are entitled to receive up to an aggregate of (i) $80.0 million upon the achievement of specified development milestones, (ii) $280.0 million upon the achievement of specified commercial milestones and (iii) $740.0 million upon the achievement of specified sales milestones. If a licensed product is approved for marketing in the Takeda Territory, we will be entitled to receive royalty payments based on tiered increments of annual net sales in the Takeda Territory, with such percentage ranging from the low double-digits to high teens, subject to specified potential royalty reductions.

Previous wording

Other income (expense), net primarily consists of unrealized and realized gains and losses on foreign currency.

Current wording

Other expense, net consists of unrealized and realized gains and losses on foreign currency and other taxes and fees.

Previous wording

The tax provision recorded for the year ended December 31, 2024 resulted from withholding tax related to taxable income generated from the Hansoh Agreement. We have not recorded any income tax benefits for the losses incurred as it is more likely than not that these benefits will not be realized based on our history of losses and expected future losses.

Current wording

The tax provision recorded for the year ended December 31, 2025 resulted from income tax related to taxable income generated from the Takeda Agreement. We continue to maintain a full valuation allowance against our net deferred tax assets due to our history of losses and expected future losses.

Previous wording

Research and development expenses were $173.6 million for the year ended December 31, 2024, compared to $135.3 million for the year ended December 31, 2023. The increase of $38.4 million was primarily due to an increase in program-related costs, including (i) an $8.8 million increase of cibotercept-related expenses, which was driven by a $7.1 million increase in clinical spend associated with our Phase 2 clinical trial and a $1.7 million increase in manufacturing costs; (ii) a $10.1 million increase in KER-065-related expenses, primarily driven by a net increase of $5.8 million in manufacturing and preclinical activities and an increase of $4.3 million in clinical spend associated with our ongoing Phase 1 clinical trial; (iii) a net increase of $3.1 million of elritercept-related expenses, primarily driven by a $9.7 million increase in clinical spend associated with our ongoing Phase 2 clinical trials, one in patients with MDS and one in patients with myelofibrosis, and the advancement of a Phase 3 clinical trial in patients with MDS, partially offset by a decrease of $6.6 million in manufacturing and preclinical activities; (iv) a $12.5 million increase in personnel costs, including an increase of $4.2 million of additional stock-based compensation costs, driven by the increase in headcount to support the advancement of our pipeline; (v) a $1.8 million increase in professional fees; and (v) a $2.4 million increase in facilities and supplies and other expenses due to the continued growth of our organization. These increases were partially offset by a $0.4 million decrease in preclinical pipeline and development activities.

Current wording

Research and development expenses were $129.6 million for the year ended December 31, 2025, compared to $173.6 million for the year ended December 31, 2024. The decrease of $44.0 million was primarily due to a decrease in program-related costs, including (i) a $9.0 million decrease of rinvatercept-related expenses, which was driven by a net decrease of $7.8 million in manufacturing and preclinical activities and a $1.2 million decrease in clinical spend associated with our completed Phase 1 clinical trial; (ii) a net decrease of $6.3 million in elritercept-related expenses, primarily driven by a decrease of $8.4 million in clinical spend associated with our ongoing Phase 2 clinical trials, one in patients with MDS and one in patients with myelofibrosis, and the advancement of the Phase 3 RENEW clinical trial, as clinical activities transitioned to Takeda during 2025, partially offset by an increase of $2.1 million in manufacturing activities; (iii) a $17.2 million decrease of cibotercept-related expenses, primarily driven by a $9.5 million decrease in clinical spend associated with our terminated Phase 2 clinical trial and a net decrease of $7.7 million in manufacturing and preclinical activities; (iv) a $5.2 million decrease in preclinical pipeline and development activities; and (v) a $8.3 million decrease in personnel costs, including a decrease of $5.0 million of stock-based compensation costs, driven by a reduction in headcount. These decreases were partially offset by (a) a $1.4 million increase in professional fees and (b) a net increase of $0.6 million in facilities and supplies and other expenses.

Previous wording

General and administrative expenses were $40.8 million for the year ended December 31, 2024, compared to $34.8 million for the year ended December 31, 2023. The increase of $5.9 million was primarily due to (i) a $3.6 million increase in personnel expenses, which includes an increase of $1.9 million of additional stock-based compensation costs, to support our organizational growth and achievement of our corporate goals; (ii) a net $0.6 million increase in facilities, supplies and other expenses due to growth of our organization; and (iii) a $2.3 million increase in professional fees. These increases were partially offset by a $0.6 million decrease in director and officer insurance premiums.

Current wording

General and administrative expenses were $46.8 million for the year ended December 31, 2025, compared to $40.8 million for the year ended December 31, 2024. The increase of $6.1 million was primarily due to (i) a $5.9 million increase in professional fees and (ii) a net $0.9 million increase in facilities, supplies and other expenses. These increases were partially offset by (a) a $0.6 million decrease in personnel expenses, which includes a decrease of $1.2 million of stock-based compensation costs, partially offset by a net increase of $0.5 million in salaries and bonus, severance, benefits and other payroll costs and (b) a $0.1 million decrease in director and officer insurance premiums.

Previous wording

Total other income (expense), net was $23.8 million for the year ended December 31, 2024, compared to $16.9 million for the year ended December 31, 2023. The increase of $6.8 million is primarily related to an increase of $8.7 million of dividend income, partially offset by (i) a decrease of $1.2 million in R&D Incentive income in Australia; and (ii) an increase of $0.7 million in other expense, net.

Current wording

Total other income, net was $24.3 million for the year ended December 31, 2025, compared to $23.8 million for the year ended December 31, 2024. The increase of $0.5 million was primarily related to (i) an increase of $1.4 million of dividend income and (ii) a decrease of $0.4 million in other expense, net, partially offset by a decrease of $1.2 million in R&D Incentive income in Australia.

Previous wording

Income tax provision was $0.3 million for the year ended December 31, 2024, compared to zero for the years ended December 31, 2023, and 2022, respectively. The increase of $0.3 million in income tax provision is attributed to withholding taxes related to the taxable income generated in 2024 from the Hansoh Agreement.

Current wording

Income tax provision was $4.9 million for the year ended December 31, 2025, compared to $0.3 million for the year ended December 31, 2024. The increase of $4.6 million in income tax provision is attributed to taxable income generated from the Takeda Agreement.

Previous wording

Since our inception, we have incurred significant operating losses. Our net losses were $187.4 million, $153.0 million, and $104.7 million for the years ended December 31, 2024, 2023, and 2022, respectively. As of December 31, 2024 and December 31, 2023, we had an accumulated deficit of $568.8 million and $381.4 million, respectively. To date, we have devoted the majority of our efforts into business planning, research and development of our product candidates, including conducting clinical trials and preclinical studies, raising capital and recruiting management and technical staff to support these operations. Our primary uses of cash are to fund operating expenses, primarily research and development expenditures. We expect our expenses to increase substantially in connection with our ongoing activities, particularly as we advance the preclinical activities and clinical trials of our product candidates. Furthermore, we expect to incur additional costs associated with operating as a public company, including significant legal, accounting, investor relations, director and officer insurance premiums and other expenses. In addition, if we obtain marketing approval for any of our product candidates, we expect to incur significant commercialization expenses related to establishing sales, marketing, distribution and other commercial infrastructure to commercialize such products.

Current wording

Since our inception, we have incurred significant operating losses each fiscal year through December 31, 2024. Our net income, which was primarily driven by the one-time upfront fee related to the Takeda Agreement, was $87.0 million for the year ended December 31, 2025, compared to a net loss of $187.4 million for the year ended December 31, 2024. As of December 31, 2025 and December 31, 2024, we had an accumulated deficit of $481.8 million and $568.8 million, respectively. To date, we have devoted the majority of our efforts into business planning, research and development of our product candidates, including conducting clinical trials and preclinical studies, raising capital and recruiting management and technical staff to support these operations. Our primary uses of cash are to fund operating expenses, primarily research and development expenditures. We expect to continue to incur substantial expenses in connection with our ongoing activities, particularly as we advance the preclinical studies and clinical trials of our product candidates. Furthermore, we expect to incur costs associated with operating as a public company, including significant legal, accounting, investor relations, director and officer insurance premiums and other expenses. In addition, if we obtain marketing approval for any of our product candidates, we expect to incur significant commercialization expenses related to establishing sales, marketing, distribution and other commercial infrastructure to commercialize such products.

Previous wording

We currently do not have any products approved for sale. We do not expect to generate any revenue from product sales unless and until we successfully complete development and obtain regulatory approval for one or more of our product candidates, which we expect will take a number of years. Since our inception, we have funded our operations primarily through equity financings and through research collaborations or licensing of intellectual property.

Current wording

We currently do not have any products approved for sale. We do not expect to generate any revenue from product sales unless and until we successfully complete development and obtain regulatory approval for one or more of our product candidates, which we expect will take a number of years. Since our inception, we have funded our operations primarily through equity financings, research collaborations or licensing of intellectual property.

Previous wording

In December 2022, we filed a prospectus supplement to a registration statement on Form S-3ASR, including a base prospectus and sales agreement prospectus, or the Prior Shelf Registration Statement, for the issuance and sale of up to $250.0 million of shares of our common stock. On May 3, 2024, we filed a new registration statement on Form S-3ASR, or the New Shelf Registration Statement, to replace the Prior Shelf Registration Statement that was set to expire, which became automatically effective upon filing, and which permits us to offer, from time to time, an unspecified amount of common stock, preferred stock, debt securities and warrants, including through an “at the market” program with Leerink, as sales agent, or the ATM Program. As of and during the year ended December 31, 2024, we have sold a total of 4,290,096 shares of our common stock pursuant to the ATM Program for aggregate net proceeds of approximately $228.6 million after deducting sales agent commissions and estimated offering expenses. As of December 31, 2024, we were eligible to offer and sell, from time to time, shares of our common stock for an aggregate offering amount of up to the remaining $117.7 million available under the ATM Program. We anticipate that the filing of this Annual Report on Form 10-K will render us unable to use our currently effective New Shelf Registration Statement as we expect that, on the date of filing of this report, we will no longer meet the criteria of a well-known seasoned issuer. Accordingly, we will need to file a post-effective amendment to the New Shelf Registration Statement to convert it to a non-automatic shelf registration statement that we are eligible to use, or to file a new shelf registration statement on Form S-3. Such post-effective amendment or shelf registration statement on Form S-3 is subject to review by the SEC and must be declared effective by the SEC, which could delay our ability to raise debt or equity capital under the registration statement and may adversely affect our ability to access financing and the capital markets in a timely fashion.

Current wording

In December 2022, we filed a prospectus supplement to a registration statement on Form S-3ASR, including a base prospectus and sales agreement prospectus, or the Prior Shelf Registration Statement, for the issuance and sale of up to $250.0 million of shares of our common stock. On May 3, 2024, we filed a new registration statement on Form S-3ASR, or the New Shelf Registration Statement, to replace the Prior Shelf Registration Statement that was set to expire, which became automatically effective upon filing, and which permits us to offer, from time to time, an unspecified amount of common stock, preferred stock, debt securities and warrants, including through an “at the market” program with Leerink, as sales agent, or the ATM Program. As of the filing of our Annual Report on Form 10-K for the year ended December 31, 2024, we no longer qualified as a well-known seasoned issuer and therefore were not eligible to use the New Shelf Registration Statement as an automatic shelf registration statement. As of December 31, 2025, we have sold a total of 4,290,096 shares of our common stock pursuant to the ATM Program. As of December 31, 2025, we were not eligible to offer and sell any shares of our common stock under the ATM Program and did not sell any shares during the year ended December 31, 2025.

Previous wording

As of December 31, 2024, we had cash and cash equivalents of $559.9 million. Based on our current operating assumptions, we believe that our existing cash and cash equivalents, together with the $200.0 million upfront payment pursuant to the license agreement with Takeda, or the Takeda Agreement, which we received in February 2025, will be sufficient to fund our projected liquidity requirements into 2029. We have based this estimate on assumptions that may prove to be wrong, and we could use our capital resources sooner than we currently expect. Due to the numerous risks and uncertainties associated with the development of our product candidates and programs, and because the extent to which we may enter into collaborations with third parties for development of our product candidates is unknown, we are unable to estimate the timing and amounts of increased capital outlays and operating expenses associated with completing the research and development of our product candidates. Our future funding requirements, both near and long-term, will depend on many factors, including:

Current wording

As of December 31, 2025, we had cash and cash equivalents of $287.4 million. Based on our current operating assumptions, we believe that our existing cash and cash equivalents will be sufficient to fund our projected liquidity requirements into the first half of 2028. We have based this estimate on assumptions that may prove to be wrong, and we could use our capital resources sooner than we currently expect. Due to the numerous risks and uncertainties associated with the development of our product candidates and programs, and because the extent to which we may enter into collaborations with third parties for development of our product candidates is unknown, we are unable to estimate the timing and amounts of increased capital outlays and operating expenses associated with completing the research and development of our product candidates. Our future funding requirements, both near and long-term, will depend on many factors, including:

Previous wording

▪the timing and amount of milestone and royalty payments we are required to make or are eligible to receive under our license agreements with each of The General Hospital Corporation and Hansoh;

Current wording

▪the timing and amount of milestone and royalty payments we are required to make or are eligible to receive under our license agreements with each of The General Hospital Corporation, Hansoh and Takeda;

Previous wording

▪the cost of manufacturing cibotercept, KER-065, elritercept and future product candidates for clinical trials in preparation for marketing approval and in preparation for commercialization;

Current wording

▪the cost of manufacturing rinvatercept and future product candidates for clinical trials in preparation for marketing approval and in preparation for commercialization;

Previous wording

In addition, public health crises, bank failures, geopolitical tensions and resulting global slowdown of economic activity continue to rapidly evolve and have already resulted in a significant disruption of global financial markets. If the disruption persists and deepens, we could experience an inability to access additional capital when and if needed. If we are unable to obtain funding, we could be forced to delay, reduce or eliminate some or all of our research and development programs and clinical development efforts, which would adversely affect our business prospects, or we may be unable to continue operations. We do not have any committed external source of funds or other support for our development efforts and we cannot be certain that additional funding will be available on acceptable terms, or at all. Until we can generate sufficient product or royalty revenue to finance our cash requirements, which we may never do, we expect to finance our future cash needs through a combination of public or private equity offerings, debt financings, collaborations, strategic alliances, licensing arrangements and other marketing or distribution arrangements. Adequate additional funding may not be available to us on acceptable terms, or at all. Any failure to raise capital as and when needed could have a negative impact on our financial condition and on our ability to pursue our business plans and strategies.

Current wording

In addition, implementation of tariffs, public health crises, bank failures, geopolitical tensions and resulting global slowdown of economic activity continue to rapidly evolve and have already resulted in a significant disruption of global financial markets. If the disruption persists and deepens, we could experience an inability to access additional capital when and if needed. If we are unable to obtain funding, we could be forced to delay, reduce or eliminate some or all of our research and development programs and clinical development efforts, which would adversely affect our business prospects, or we may be unable to continue operations. We do not have any committed external source of funds or other support for our development efforts and we cannot be certain that additional funding will be available on acceptable terms, or at all. Until we can generate sufficient product or royalty revenue to finance our cash requirements, which we may never do, we expect to finance our future cash needs through a combination of public or private equity offerings, debt financings, collaborations, strategic alliances, licensing arrangements and other marketing or distribution arrangements. Adequate additional funding may not be available to us on acceptable terms, or at all. Any failure to raise capital as and when needed could have a negative impact on our financial condition and on our ability to pursue our business plans and strategies.

Previous wording

Net cash used in investing activities was $1.9 million, $2.5 million, and $1.2 million for the years ended December 31, 2024, 2023, and 2022, respectively. The cash used in investing activities in each period was due to purchases of property and equipment.

Current wording

Net cash used in investing activities was $1.6 million and $1.9 million for the years ended December 31, 2025 and 2024, respectively. The cash used in investing activities in each period was due to purchases of property and equipment.

Previous wording

We enter into agreements in the normal course of business with contract manufacturing organizations for process development, raw material purchases and manufacturing services. These contracts typically do not contain minimum purchase commitments and are generally cancellable by us upon written notice. Payments due upon cancellation consist of payments for services provided or expenses incurred, including noncancellable obligations of our service providers, up to the date of cancellation and, in the case of certain arrangements with contract manufacturing organizations, may include noncancellable fees. Under such agreements, the exact amounts owed by us in the event of termination will be based on the timing of the termination and the exact terms of the agreement. As of December 31, 2024, we have committed up to approximately $27.2 million under these agreements which are expected to be paid through 2029.

Current wording

We enter into agreements in the normal course of business with contract manufacturing organizations for process development, raw material purchases and manufacturing services. These contracts typically do not contain minimum purchase commitments and are generally cancellable by us upon written notice. Payments due upon cancellation consist of payments for services provided or expenses incurred, including noncancellable obligations of our service providers, up to the date of cancellation and, in the case of certain arrangements with contract manufacturing organizations, may include noncancellable fees. Under such agreements, the exact amounts owed by us in the event of termination will be based on the timing of the termination and the exact terms of the agreement. As of December 31, 2025, we have committed up to approximately $1.6 million under these agreements which are expected to be paid through 2029.

Previous wording

The consideration allocated to each performance obligation is recognized as revenue when control is transferred for the related goods or services. For performance obligations which consist of licenses and other promises, we utilize judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress. We evaluate the measure of progress each reporting period and, if necessary, adjust the measure of performance and related revenue recognition.

Current wording

The consideration allocated to each performance obligation is recognized as revenue when control is transferred for the related goods or services. If the license to our intellectual property is determined to be distinct from the other performance obligations identified in the arrangement, we recognize revenue from consideration allocated to the license when the license is transferred to the customer and the customer can use and benefit from the license. For performance obligations which consist of licenses and other promises, we utilize judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress. We evaluate the measure of progress each reporting period and, if necessary, adjust the measure of performance and related revenue recognition.

Previous wording

We account for all stock-based compensation awards granted to employees and non-employees as stock-based compensation expense at fair value. Our stock-based awards include stock options and performance-based stock options. The measurement date for awards is the date of grant. For stock options that vest based on service conditions, stock-based compensation costs are recognized as expense over the requisite service period, which is the vesting period, on a straight-line basis. For stock options with performance conditions, stock-based compensation costs are recognized as expense using the accelerated attribution method when it is probable that the performance condition will be achieved. Our Black-Scholes option-pricing model requires the input of subjective assumptions, including the expected volatility of the price of our common stock. We lack company-specific historical and implied volatility information. Therefore, we estimate our expected stock volatility based on the historical volatility of a publicly traded set of peer companies and expect to continue to do so until such time as we have adequate historical data regarding the volatility of our own traded stock price. These estimates involve inherent uncertainties and the application of management’s judgment. If factors change and these assumptions either increase or decrease, our stock-based compensation expense could materially differ in the future. Stock-based compensation expense is classified in the accompanying statements of operations based on the function to which the related services are provided. We recognize stock-based compensation expense for the portion of awards that have vested. Forfeitures are recorded as they occur. The fair value of each stock option grant is estimated on the date of grant using the Black-Scholes option-pricing model.

Current wording

We account for all stock-based compensation awards granted to employees and non-employees as stock-based compensation expense at fair value. Our stock-based awards include stock options and restricted stock unit, or RSU, awards. The measurement date for awards is the date of grant. For stock-based awards that vest based on service conditions, stock-based compensation costs are recognized as expense over the requisite service period, which is the vesting period, on a straight-line basis. For stock options and RSUs with performance conditions, stock-based compensation costs are recognized as expense using the accelerated attribution method when it is probable that the performance condition will be achieved. Our Black-Scholes option-pricing model requires the input of subjective assumptions, including the expected volatility of the price of our common stock. We lack company-specific historical and implied volatility information. Therefore, we estimate our expected stock volatility based on the historical volatility of a group of publicly traded peer companies, weighted with our own historical volatility for the period during which our stock has been publicly traded. These estimates involve inherent uncertainties and the application of management’s judgment. If factors change and these assumptions either increase or decrease, our stock-based compensation expense could materially differ in the future. Stock-based compensation expense is classified in the accompanying statements of operations based on the function to which the related services are provided. We recognize stock-based compensation expense for the portion of awards that have vested. Forfeitures are recorded as they occur. The fair value of each stock option grant is estimated on the date of grant using the Black-Scholes option-pricing model.