IONIS PHARMACEUTICALS INC
For the period ended Dec 31, 2025. Filed Feb 26, 2026.
View on SEC.govAbout this filing
A company's yearly report to the SEC, with audited financial statements. It is the fullest account a company gives of its business, its finances and the risks it sees.
FY2025 · Filed Feb 26, 2026
IONS$39.42+1.6%Stored close · as of Nov 6, 2026
What changed in Management’s Discussion and Analysis?
Read the current filingPrevious report: 10-K
Period ended 2024-12-31; filed 2025-02-19.
0000874015-25-000089
Item 7. Management’s Discussion and Analysis of Financial Condition and Results of OperationsCurrent report: 10-K
Period ended 2025-12-31; filed 2026-02-26.
0000874015-26-000115
Item 7. Management’s Discussion and Analysis of Financial Condition and Results of OperationsThe baseline is this issuer’s latest earlier reporting period of the same form that was filed before the current report. A previous 10-Q is a different quarter, not a year-over-year comparison. Amendments are excluded.
Compared 108 previous paragraphs and 116 current paragraphs.
78 unchanged; 22 reworded; 14 added; 7 removed; 1 previous and 2 current paragraphs rearranged.
Tables are not compared: 22 previous and 14 current tables excluded. Dates, whitespace, punctuation and numbering changes are ignored; changes to financial figures remain significant.
A changed paragraph is not evidence that risk increased or decreased. An unchanged paragraph does not establish that risk stayed the same.
Added paragraphs (14)
Current report
Commercial revenue in 2025 increased 49 percent compared to 2024. This increase was primarily driven by TRYNGOLZA product sales and higher royalty revenue.
Current report
The remainder of our revenue came from programs under our R&D collaborations, including a $280 million upfront payment for the global license of sapablursen to Ono in the second quarter of 2025, reflecting the value that our pipeline and technology continues to generate.
Current report
Costs of sales for recently launched products, such as TRYNGOLZA and DAWNZERA, does not include the full cost of manufacturing until we manufacture and sell additional inventory after exhausting pre-launch inventory, which we previously recorded as R&D expense.
Current report
Drug discovery expenses, excluding non-cash compensation expense related to equity awards, increased in 2025 compared to 2024 as we continued to advance our technologies discussed above.
Current report
R&D support expenses, excluding non-cash compensation expense related to equity awards, increased in 2025 compared to 2024 primarily due to increased costs relating to computer software and licenses.
Current report
Gain (Loss) on Investments
Current report
In July 2025, H.R.1 - 119th Congress was signed into law, introducing significant changes to U.S. federal tax law. The new law restores current expensing of domestic R&D costs and allows us to accelerate the deduction for a significant amount of such costs we capitalized since 2022. These tax law changes did not have a material effect on our tax expense for the year ended December 31, 2025.
Current report
Our working capital decreased from 2024 to 2025 as we reclassified our 0% Notes due 2026 from non-current liabilities to current liabilities in the second quarter of 2025 because the notes are due in April 2026. During the same period, our long-term obligations increased due to the issuance of our 0% Notes due 2030, which was partially offset by the partial repurchase of our 0% Notes due 2026, in the fourth quarter of 2025.
Current report
● Assessing the propriety of revenue recognition and associated deferred revenue;
Current report
● Determining the appropriate cost estimates for unbilled preclinical studies and clinical development activities; and
Current report
Identifying the performance obligations contained in the agreement
Current report
Determining the transaction price, including any variable consideration
Current report
Whether a milestone payment is probable (discussed in detail above under “Determining the transaction price, including any variable consideration”); and
Current report
If we are performing services, we recognize revenue over our estimated period of performance in a similar manner to the amortization of upfront payments (discussed above under “R&D Services with Upfront Payments”).
Removed paragraphs (7)
Previous report
Commercial revenue in 2024 included new sources of commercial revenue with the launch of WAINUA in the U.S. in late January 2024 and the launch of TRYNGOLZA in the U.S. in late December 2024. SPINRAZA royalties in 2024 compared to 2023 were impacted from an annual order from a single country that did not recur in 2024.
Previous report
R&D revenue decreased in 2024 compared to 2023 primarily due to the decrease in WAINUA joint development revenue as development activities relating to ATTRv-PN wound down with the commercial launch of WAINUA. In addition, R&D revenue decreased due to the timing of significant partner payments.
Previous report
Drug discovery expenses, excluding non-cash compensation expense related to equity awards, decreased in 2024 compared to 2023. In 2023, we recognized $15 million in R&D expense for licensing Vect-Horus’ platform technology.
Previous report
Interest expense for 2024 was $17.0 million compared to $12.7 million for 2023. In June 2023, we completed a $575.0 million offering of our 1.75% Notes and repurchased $504.4 million in principal of our 0.125% Notes. As a result, beginning in the second quarter of 2023, our interest expense related to our convertible notes included interest expense incurred for our 1.75% Notes. Interest expense in 2024 included a full year of interest expense related to our 1.75% Notes.
Previous report
Loss on Investments
Previous report
The decrease in income tax expense for 2024 compared to 2023 primarily related to the impact of the Royalty Pharma transaction in 2023. We reflected the Royalty Pharma transaction as a taxable sale, which required us to include the proceeds from the sale, net of currently deductible issuance costs, as taxable income in 2023.
Previous report
Our working capital increased from 2023 to 2024 primarily due to a decrease in current liabilities as a result of lower deferred contract revenue as of December 31, 2024 compared to December 31, 2023. During the same period, our long-term obligations did not change significantly.
Reworded paragraphs (22)
Previous wording
As noted in our Business Overview in Part I, Item 1, Business, for three decades, we have invented medicines that we believe bring better futures to people with serious diseases. Today, as a pioneer in RNA-targeted medicines, we continue to drive innovation in RNA therapies. We currently have six marketed medicines: TRYNGOLZA, WAINUA, SPINRAZA, QALSODY, TEGSEDI and WAYLIVRA. We also have a rich innovative late- and mid-stage pipeline in neurology, cardiology and rare diseases. We currently have nine medicines in Phase 3 development and additional medicines in early and mid-stage development. Refer to Part I, Item 1, Business, for further details on our business and key developments in our medicines.
Current wording
As noted in our Business Overview in Part I, Item 1, Business, for three decades, we have invented medicines that we believe bring better futures to people with serious diseases. Today, as a pioneer in RNA-targeted medicines, we continue to drive innovation in RNA therapies. We currently have seven marketed medicines: TRYNGOLZA, DAWNZERA, WAINUA, SPINRAZA, QALSODY, TEGSEDI and WAYLIVRA. We also have a rich innovative late- and mid-stage pipeline in neurology, cardiometabolic diseases and select areas of high patient needs. We currently have nine medicines in Phase 3 development and additional medicines in early and mid-stage development. Refer to Part I, Item 1, Business, for further details on our business and key developments in our medicines.
Previous wording
Below we have included our results of operations for 2024 compared to 2023. Refer to Part II, Item 7, Management’s Discussion and Analysis of Financial Condition and Results of Operations, of our 2023 Form 10-K for our results of operations for 2023 compared to 2022. The following table provides selected summary information from our consolidated statements of operations for 2024 and 2023 (in millions):
Current wording
The following table provides selected summary information from our consolidated statements of operations for 2025 and 2024 (in millions):
Previous wording
Total revenue for 2024 was $705.1 million compared to $787.6 million in 2023 and was comprised of the following (in millions):
Current wording
Total revenue for 2025 was $943.7 million compared to $705.1 million in 2024 and was comprised of the following (in millions):
Previous wording
Our financial results for the years ended December 31, 2024 and 2023 reflected the cost-sharing provisions related to our collaboration with AstraZeneca to develop and commercialize WAINUA for the treatment of ATTR. Under the terms of the collaboration agreement, AstraZeneca is currently paying 55 percent of the costs associated with the ongoing global Phase 3 development program. Because we are leading and conducting the Phase 3 development program, we are recognizing as R&D revenue the 55 percent of cost-share funding AstraZeneca is responsible for, net of our share of AstraZeneca’s development expenses, in the same period we incur the related development expenses.
Current wording
Our financial results for the years ended December 31, 2025 and 2024 reflected the cost-sharing provisions related to our collaboration with AstraZeneca to develop and commercialize WAINUA for the treatment of ATTR. Under the terms of the collaboration agreement, AstraZeneca was responsible for 55 percent of the costs associated with the ongoing global Phase 3 development program through December 31, 2025. After December 31, 2025, AstraZeneca is responsible for 75 percent and 87.5 percent of development costs in the U.S. and the rest of the world, respectively. Because we are leading and conducting the Phase 3 development program, we are recognizing as R&D revenue the percentage of cost-share funding AstraZeneca is responsible for, net of our share of AstraZeneca’s development expenses, in the same period we incur the related development expenses.
Previous wording
Our WAINUA joint development revenue in 2024 and 2023 includes a $30 million milestone payment from AstraZeneca that we earned when the MHRA approved WAINUA for ATTRv-PN in the UK as WAINZUA and a $50 million milestone payment from AstraZeneca that we earned when the FDA approved WAINUA for ATTRv-PN in the U.S., respectively.
Current wording
Our WAINUA joint development revenue in 2024 included a $30 million milestone payment from AstraZeneca that we earned when the Medicines and Healthcare products Regulatory Agency, or MHRA, approved WAINUA for ATTRv-PN in the UK as WAINZUA. Research and development expenses related to the Phase 3 development of WAINUA decreased in 2025 compared to 2024 as development activities related to ATTRv-PN continued to wind down with the commercial launch of WAINUA.
Previous wording
Operating expenses, excluding non-cash compensation expense related to equity awards, increased slightly in 2024 compared to 2023. SG&A expenses increased year over year primarily due to the launches of WAINUA and TRYNGOLZA, including establishing the TRYNGOLZA field team in the second quarter of 2024, and advancing launch preparation activities for donidalorsen. R&D expenses were essentially flat year over year as several late-stage studies ended.
Current wording
Operating expenses, excluding non-cash compensation expense related to equity awards, increased in 2025 compared to 2024. SG&A expenses increased year over year primarily due to the launches of TRYNGOLZA, DAWNZERA and WAINUA.
Previous wording
Non-cash compensation expense related to equity awards increased in 2024 compared to 2023 due to increased headcount and a higher stock price on the grant date of annual equity awards in 2024 compared to 2023. We believe non-cash compensation expense related to equity awards is not indicative of our operating results or cash flows from our operations.
Current wording
Non-cash compensation expense related to equity awards were essentially flat year over year due to increased headcount offset by a lower stock price on the grant date of annual equity awards in 2025 compared to 2024. We believe non-cash compensation expense related to equity awards is not indicative of our operating results or cash flows from our operations.
Previous wording
Our cost of sales is comprised of costs related to our commercial revenue, which consisted of manufacturing costs, including certain fixed costs, transportation and freight, indirect overhead costs primarily associated with the manufacturing and distribution of TRYNGOLZA, TEGSEDI and WAYLIVRA and certain associated period costs.
Current wording
Our cost of sales is comprised of costs related to our commercial revenue, which consisted of manufacturing costs, transportation and freight, indirect overhead costs associated with the manufacturing and distribution of TRYNGOLZA, DAWNZERA, TEGSEDI and WAYLIVRA and associated period costs.
Previous wording
Our development expenses, excluding non-cash compensation expense related to equity awards, were essentially flat in 2024 compared to 2023. We expect our development expenses will continue to be stable as several late-stage studies end and we reallocate resources toward earlier stage programs.
Current wording
Our development expenses, excluding non-cash compensation expense related to equity awards, decreased in 2025 compared to 2024 as several late-stage studies ended. We expect our development expenses will continue to stabilize as several late-stage studies end and we reallocate resources toward earlier stage programs.
Previous wording
Manufacturing and development chemistry expenses, excluding non-cash compensation expense related to equity awards, decreased in 2024 compared to 2023 due to the timing of manufacturing performed by our contract manufacturing organizations for drug product related to several late-stage programs. Refer to the section titled, Manufacturing, in Part I, Item 1, Business, for further details on the activities and types of costs we incur in our manufacturing process.
Current wording
Manufacturing and development chemistry expenses, excluding non-cash compensation expense related to equity awards, increased in 2025 compared to 2024 due to the timing of manufacturing performed by our contract manufacturing organizations for drug product and active pharmaceutical ingredients related to several late-stage programs. Refer to the section titled, Manufacturing, in Part I, Item 1, Business, for further details on the activities and types of costs we incur in our manufacturing process.
Previous wording
SG&A expenses include personnel and outside costs associated with the pre-commercialization and commercialization activities for our medicines and costs to support our company, our employees and our stockholders including, legal, human resources, investor relations and finance. Additionally, we include in SG&A expenses such costs as rent, repair and maintenance of buildings and equipment, depreciation and utilities costs that we need to support the corporate functions listed above. We also include fees we owe under our in-licensing agreements related to SPINRAZA and QALSODY.
Current wording
SG&A expenses include personnel, information technology systems and outside costs associated with the commercialization and pre-commercialization activities for our medicines and costs to support our company, our employees and our stockholders including, legal, human resources, investor relations and finance. Additionally, we include in SG&A expenses such costs as rent, repair and maintenance of buildings and equipment, depreciation and utilities costs that we need to support the corporate functions listed above. We also include fees we owe under our in-licensing agreements related to SPINRAZA and QALSODY and cost sharing payments associated with the co-commercialization activities under our WAINUA collaboration with AstraZeneca.
Previous wording
SG&A expenses, excluding non-cash compensation expense related to equity awards, increased in 2024 compared to 2023 due to the launches of WAINUA and TRYNGOLZA, including establishing the TRYNGOLZA field team in the second quarter of 2024, and advancing launch preparation activities for donidalorsen. We expect SG&A expenses to increase as we continue to invest in our independent commercial launches.
Current wording
SG&A expenses, excluding non-cash compensation expense related to equity awards, increased in 2025 compared to 2024 primarily due to the launches of TRYNGOLZA, DAWNZERA and WAINUA. We expect SG&A expenses to increase as we continue to invest in our independent commercial launches.
Previous wording
Investment income for 2024 was $107.0 million compared to $89.0 million for 2023. The increase in investment income was primarily due to an increase in interest rates associated with our investments during a majority of 2024 compared to 2023. In addition, our cash available for investing increased due to the $489.1 million net proceeds we received from our public common stock offering in September 2024. Refer to Part IV, Item 15, Note 8, Stockholders’ Equity, in the Notes to the Consolidated Financial Statements for further details on the public offering.
Current wording
Investment income for 2025 was $97.8 million compared to $107.0 million for 2024. The decrease in investment income was primarily due to a decrease in interest rates associated with our investments during 2025 compared to 2024.
Previous wording
We recorded $73.5 million and $68.8 million of interest expense related to the sale of future royalties in 2024 and 2023, respectively. These amounts are related to the Royalty Pharma Investments, or Royalty Pharma, transaction, in which we sold a minority interest in our future SPINRAZA and pelacarsen royalties to Royalty Pharma for a $500 million upfront payment and $625 million of potential future payments. Refer to Part IV, Item 15, Note 7, Long-Term Obligations and Commitments, in the Notes to the Consolidated Financial Statements for further details.
Current wording
We recorded $73.3 million and $73.5 million of interest expense related to the sale of future royalties in 2025 and 2024, respectively. These amounts are related to the Royalty Pharma Investments, or Royalty Pharma, transaction, in which we sold a minority interest in our future SPINRAZA and pelacarsen royalties to Royalty Pharma for a $500 million upfront payment and $625 million of potential future payments. Refer to Part IV, Item 15, Note 7, Long-Term Obligations and Commitments, in the Notes to the Consolidated Financial Statements for further details.
Previous wording
We recorded a $2.9 million and $1.9 million loss on investments for 2024 and 2023, respectively. The period-over-period fluctuation in our loss on investments was primarily driven by changes in the fair value of our investments in privately held and publicly traded biotechnology companies.
Current wording
We recorded a $10.2 million gain on investments and a $2.9 million loss on investments for 2025 and 2024, respectively. The period-over-period fluctuation in our gain (loss) on investments was primarily driven by changes in the fair value of our investments in privately held and publicly traded biotechnology companies.
Previous wording
In 2023, we completed a $575.0 million offering of our 1.75% Notes and used $488.2 million of the net proceeds to repurchase $504.4 million in principal of our 0.125% Notes. As a result of these repurchases, we recorded a $13.4 million gain on early retirement of debt in 2023, which reflects the difference between the amounts we paid to repurchase portions of our 0.125% Notes and the net carrying balance of the liability at the time that we repurchased the debt. Refer to Part IV, Item 15, Note 7, Long-Term Obligations and Commitments, in the Notes to the Consolidated Financial Statements for further details regarding our convertible debt.
Current wording
In 2025, we completed a $770.0 million offering of our 0% Notes due 2030 and used $267.6 million of the net proceeds to repurchase $200.0 million in principal of our 0% Notes due 2026 at a premium. As a result of the repurchase, we recognized induced conversion expense of $16.3 million, which we recorded as other expense in our consolidated statement of operations for the year ended December 31, 2025. The induced conversion expense is the difference between the amount paid to repurchase the 0% Notes due 2026 and the if-converted value of the notes at the time that the debt repurchase terms were finalized. Refer to Part IV, Item 15, Note 7, Long-Term Obligations and Commitments, in the Notes to the Consolidated Financial Statements for further details regarding our convertible debt.
Previous wording
We recorded an income tax benefit of $6.2 million for 2024 compared to an income tax expense of $32.3 million for 2023.
Current wording
We recorded an income tax expense of $1.8 million for 2025 compared to an income tax benefit of $6.2 million for 2024.
Previous wording
The income tax benefit during 2024 primarily related to adjustments to prior year tax return positions for the royalty purchase agreement with Royalty Pharma and deductions related to foreign SPINRAZA royalties.
Current wording
The income tax expense for 2025 primarily relates to state income taxes, partially offset by a federal tax benefit related to a capital loss carryback. The income tax benefit for 2024 primarily related to adjustments to prior year tax return positions for the royalty purchase agreement with Royalty Pharma and deductions related to foreign SPINRAZA royalties.
Previous wording
We generated a net loss of $453.9 million for 2024 compared to $366.3 million for 2023. Our net loss increased for 2024 compared to 2023 primarily due to factors discussed in the sections above. Basic and diluted net loss per share for 2024 were $3.04 compared to $2.56 for 2023. Our net loss per share increased for 2024 compared to 2023 primarily due to factors discussed in the sections above.
Current wording
We generated a net loss of $381.4 million for 2025 compared to $453.9 million for 2024. Our net loss decreased for 2025 compared to 2024 primarily due to factors discussed in the sections above. Basic and diluted net loss per share for 2025 were $2.38 compared to $3.04 for 2024. Our net loss per share decreased for 2025 compared to 2024 primarily due to factors discussed in the sections above.
Previous wording
We have financed our operations primarily from research and development collaborative agreements. We also financed our operations from commercial revenue from SPINRAZA royalties and TEGSEDI and WAYLIVRA commercial revenue. In addition, we began receiving commercial revenue from WAINUA royalties in 2024. From our inception through December 31,2024, we have earned approximately $7.9 billion in revenue. We have also financed our operations through the sale of our equity securities, the issuance of long-term debt, the sale leaseback of facilities and the sale of future royalties. From the time we were founded through December 31, 2024, we have raised net proceeds of approximately $2.6 billion from the sale of our equity securities, which includes our sale of 11.5 million shares of common stock for net proceeds of $489 million in September 2024. Additionally, from our inception through December 31, 2024, we have borrowed approximately $2.7 billion under long-term debt arrangements and received proceeds of approximately $0.5 billion from the sale of future royalties to finance a portion of our operations.
Current wording
We have financed our operations primarily from research and development collaborative agreements. We also financed our operations from commercial revenue from SPINRAZA, WAINUA and QALSODY royalties and TEGSEDI and WAYLIVRA commercial revenue. In addition, we began earning commercial revenue from TRYNGOLZA product sales in late December 2024 and DAWNZERA product sales in late August 2025. From our inception through December 31,2025, we have earned approximately $8.9 billion in revenue. We have also financed our operations through the sale of our equity securities, the issuance of long-term debt and the sale of future royalties. From the time we were founded through December 31, 2025, we have raised net proceeds of approximately $2.8 billion from the sale of our equity securities. Additionally, from our inception through December 31, 2025, we have borrowed approximately $3.5 billion under long-term debt arrangements and received proceeds of approximately $0.5 billion from the sale of future royalties to finance a portion of our operations.
Previous wording
Our contractual obligations consist primarily of our convertible debt. In addition, we also have a facility mortgage, facility leases, equipment financing arrangements and other obligations. We believe our cash, cash equivalents and short-term investments, as well as plans for cash in the future, will be sufficient to fund our planned operations and these obligations. We have not entered into, nor do we currently have, any off-balance sheet arrangements (as defined under SEC rules).
Current wording
Our contractual obligations consist primarily of our convertible debt. In addition, we also have a facility mortgage, facility leases, equipment financing arrangements and other obligations. In the third quarter of 2025, our build-to-suit lease in Carlsbad, California commenced, resulting in an increase to our contractual obligations related to operating leases. We believe our cash, cash equivalents and short-term investments, as well as plans for cash in the future, will be sufficient to fund our planned operations and these obligations. We have not entered into, nor do we currently have, any off-balance sheet arrangements (as defined under SEC rules).
Previous wording
As of December 31, 2024, a hypothetical 10 percent increase in our liability for preclinical and clinical development costs would have resulted in an increase in our loss before income tax benefit and accrued liabilities of approximately $7.7 million.
Current wording
As of December 31, 2025, a hypothetical 10 percent increase in our liability for preclinical and clinical development costs would have resulted in an increase in our loss before income tax benefit and accrued liabilities of approximately $5.4 million.
Rearranged current paragraphs (2)
Current report — wording carried from elsewhere
● Assessing the appropriate estimate of anticipated future royalty payments under our royalty purchase agreement.
Current report — wording carried from elsewhere
Allocating the transaction price to each of our performance obligations
Rearranged previous paragraphs (1)
Previous report — wording carried elsewhere
R&D support expenses, excluding non-cash compensation expense related to equity awards, were essentially flat in 2024 compared to 2023.