0001193125-26-333233 | 10-Q | XBRL Viewer | Ultragenyx Pharmaceutical INC

Strategic Restructuring Plan

6 Months Ended

Jun. 30, 2026

Restructuring and Related Activities [Abstract]

13. Strategic Restructuring Plan

In February 2026, the Company implemented a strategic restructuring plan designed to reduce operating expenses and focus resources on its highest value drivers. The restructuring plan included a reduction in workforce and the curtailment of certain

operating activities, including UX143 manufacturing activities. As part of the restructuring, the Company reduced its workforce by approximately 10%. The workforce reduction was substantially completed during the first quarter of 2026.

The following table presents the details of the Company’s restructuring charges and amounts paid or settled during the six months ended June 30, 2026 (in millions):


	Employee-Related			Manufacturing Related			Total
Balance as of December 31, 2025	$	—		$	—		$	—
Restructuring expense		8			22			30
Cash settled/ adjustment		(8	)		(22	)		(30	)
Balance as of June 30, 2026	$	—		$	—		$	—

Total restructuring charges recognized on the Condensed Consolidated Statements of Operations during the three and six months ended June 30, 2026 were as below (in millions):


	Three Months Ended		Six Months Ended
	June 30,		June 30,
	2026		2026
Research and development	$	—	$	28
Selling, general and administrative		—		2
Total restructuring expense	$	—	$	30

Liabilities for Sales of Future Royalties - Schedule of Key Terms and Activity of Sales of Future Royalties (Details) $ in Millions	6 Months Ended
	Jun. 30, 2026 USD ($)
2025 OMERS Agreement
Liability For Sale Of Future Royalties [Line Items]
Agreement counterparty	OMERS
Contract execution date	2025-11
Payment from sale of future royalties	$ 400
Royalties transaction costs net	$ 8
Royalties agreement territories	U.S. and Canada
Percentage of royalties sold	25.00%
Royalty start date	Jan. 01, 2028
Royalty purchase agreement cap amount	$ 620
Royalties Earned From Inception	$ 0
Effective annual interest rate	9.20%
2022 OMERS Agreement
Liability For Sale Of Future Royalties [Line Items]
Agreement counterparty	OMERS
Contract execution date	2022-07
Payment from sale of future royalties	$ 500
Royalties transaction costs net	$ 9
Royalties agreement territories	U.S. and Canada
Percentage of royalties sold	30.00%
Royalty start date	Apr. 01, 2023
Royalty purchase agreement cap amount	$ 725
Royalties Earned From Inception	$ 246
Effective annual interest rate	7.30%
RPI Finance Trust (RPI)
Liability For Sale Of Future Royalties [Line Items]
Agreement counterparty	RPI
Contract execution date	2019-12
Payment from sale of future royalties	$ 320
Royalties transaction costs net	$ 6
Royalties agreement territories	EU, U.K., and Switzerland
Percentage of royalties sold	100.00%
Royalty start date	Jan. 01, 2020
Royalty purchase agreement cap amount	$ 608
Royalty purchase agreement cap aggregate payment	800
Royalties Earned From Inception	$ 144
Effective annual interest rate	5.50%

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) (Unaudited) - $ / shares	Jun. 30, 2026	Dec. 31, 2025
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	25,000,000	25,000,000
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	250,000,000	250,000,000
Common Stock Shares Issued Not Disclosed	true	true
Common stock, shares outstanding	98,600,000	96,600,000
Treasury stock , shares	300,000	200,000

Summary of Significant Accounting Policies - Additional Information (Details) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2026 USD ($) Segment	Dec. 31, 2025 USD ($)
Accounting Policies [Abstract]
Number of reportable segments \| Segment	1
Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration]	srt:ChiefExecutiveOfficerMember
Segment Reporting, CODM, Profit (Loss) Measure, How Used, Description	The Company’s Chief Operating Decision Maker, or CODM, is the Company's Chief Executive Officer. The CODM manages the Company’s operations on an integrated basis for the purpose of allocating resources. When evaluating the Company’s financial performance, the CODM regularly reviews total revenues and total expenses and makes decisions using this information on a consolidated basis.
Credit losses recorded for receivables \| $	$ 0	$ 0

Stock-Based Awards (Tables)

6 Months Ended

Jun. 30, 2026

Share-Based Payment Arrangement [Abstract]

Summary of Stock-Based Compensation Expense

The table below sets forth the stock-based compensation expense for the periods presented (in millions):


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
Cost of sales	$	1	$	1	$	1	$	1
Research and development		18		21		34		42
Selling, general and administrative		15		17		29		36
Total stock-based compensation expense	$	34	$	39	$	64	$	79

Revenue

6 Months Ended

Jun. 30, 2026

Revenue from Contract with Customer [Abstract]

Revenue

5. Revenue

The following table disaggregates total revenues from external customers by product sales and royalty revenue (in millions):


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2026		2025		2026		2025
Product sales:
Crysvita	$	54	$	35	$	100	$	90
Dojolvi		27		23		45		40
Evkeeza		21		14		39		25
Mepsevii		10		9		17		17
Total product sales		112		81		201		172
Crysvita royalty revenue		102		86		149		134
Total revenues	$	214	$	167	$	350	$	306

The following table disaggregates total revenues based on geographic location (in millions):


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2026		2025		2026		2025
North America	$	121	$	103	$	180	$	161
Latin America		51		33		93		88
Europe, Middle East, and Africa		35		27		66		50
Asia-Pacific		7		4		11		7
Total revenues	$	214	$	167	$	350	$	306

The Company’s largest accounts receivable balance was from a collaboration partner and accounted for 47% and 62% of the total accounts receivable balance as of June 30, 2026 and December 31, 2025, respectively. Two other customers accounted for 11% and 10% of the total accounts receivable balance as of June 30, 2026 and 4% and 2% of the total accounts receivable balance as of December 31, 2025, respectively.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-9

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-10

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Subparagraph (a)
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-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147479806/606-10-50-13

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
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-URI https://asc.fasb.org/606/tableOfContent

+ Details

Strategic Restructuring Plan - Summary of total restructuring charges recognized on the condensed consolidated statements of operations (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2026	Jun. 30, 2026
Restructuring Cost and Reserve [Line Items]
Total restructuring expense	$ 0	$ 30
Research and development
Restructuring Cost and Reserve [Line Items]
Total restructuring expense	0	28
Selling, general and administrative
Restructuring Cost and Reserve [Line Items]
Total restructuring expense	$ 0	$ 2

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

Accumulated Other Comprehensive Loss

6 Months Ended

Jun. 30, 2026

Other Comprehensive Income (Loss), Net of Tax [Abstract]

Accumulated Other Comprehensive Loss

12. Accumulated Other Comprehensive Loss

Total accumulated other comprehensive loss consisted of the following (in millions):


	June 30,			December 31,
	2026			2025
Foreign currency translation adjustments	$	1		$	1
Unrealized loss on available-for-sale securities		(1	)		—
Total accumulated other comprehensive loss	$	—		$	1

Liabilities for Sales of Future Royalties

6 Months Ended

Jun. 30, 2026

Deferred Revenue Disclosure [Abstract]

Liabilities for Sales of Future Royalties

8. Liabilities for Sales of Future Royalties

The Company has entered into certain royalty purchase agreements pursuant to which it sold interests in certain future royalty payments arising from net sales of Crysvita in specified territories upon payment of the specified consideration. The

agreements will automatically terminate and the payments or royalties will cease once the aggregate payments as specified in the agreement, or the CAP, are reached.

The following table summarizes the key terms and activity to date for these arrangements (in millions except percentages):


Item	2025 OMERS Agreement	2022 OMERS Agreement	2019 RPI Agreement
Agreement counterparty	OMERS	OMERS	RPI
Contract execution date	November 2025	July 2022	December 2019
Upfront payment to Company	$400	$500	$320
Transaction costs	$8	$9	$6
Territories	U.S. and Canada	U.S. and Canada	EU, U.K., and Switzerland
Percentage of royalties sold	25%*	30%	100%
Royalty start date	January 1, 2028	April 1, 2023	January 1, 2020
CAP	$620	$725	$608 prior to Dec 31, 2030 or until aggregate payments reach $800
Royalties earned from inception to June 30, 2026	$—	$246	$144
Effective annual interest rate (as of June 30, 2026)	9.2%	7.3%	5.5%
* In addition, OMERS will continue to receive 30% of Crysvita net sales in the U.S. and Canada following the achievement of $725 million in aggregate payments under the 2022 OMERS Agreement.

Under the 2025 OMERS agreement, OMERS granted the Company an option to repurchase the entire purchased interest, that expires in November 2027, for 1.35 times the purchase price, or $540 million.

Proceeds from these transactions, net of transaction costs, were recorded as liabilities for sales of future royalties on the Consolidated Balance Sheets. The Company records the royalty revenue arising from the net sales of Crysvita in the applicable territories as royalty revenue in the Consolidated Statements of Operations over the term of the arrangements.

There are a number of factors that could materially affect the amount and timing of royalty payments from KKC in the applicable territories, most of which are not within the Company’s control. Such factors include, but are not limited to, the success of KKC’s sales and promotion of Crysvita, changing standards of care, macroeconomic and inflationary pressures, the introduction of competing products, pricing for reimbursement in various territories, manufacturing or other delays, intellectual property matters, adverse events that result in governmental health authority imposed restrictions on the use of Crysvita, significant changes in foreign exchange rates as the royalty payments are made in U.S. dollars, or USD, while significant portions of the underlying sales of Crysvita are made in currencies other than USD, and other events or circumstances that could result in reduced royalty payments from sales of Crysvita, all of which would result in a reduction of royalty revenue and the non-cash interest expense over the life of the arrangement. Conversely, if sales of Crysvita in the relevant territories are more than expected, the royalty revenue and the non-cash interest expense recorded by the Company would be greater over the term of the arrangements.

The following table shows the activity within the liability account (in millions):


	Liabilities for Sales of Future Royalties
	OMERS 2025		OMERS 2022			RPI 2019			Total
December 31, 2024	$	—	$	495		$	375		$	870
Net proceeds from sale of future royalties		392		—			—			392
Royalty revenue		—		(79	)		(29	)		(108	)
Non-cash interest expense		6		36			20			62
December 31, 2025		398		452			366			1,216
Royalty revenue		—		(41	)		(16	)		(57	)
Non-cash interest expense		18		15			10			43
June 30, 2026	$	416	$	426		$	360		$	1,202

Financial Instruments

6 Months Ended

Jun. 30, 2026

Fair Value Disclosures [Abstract]

Financial Instruments

3. Financial Instruments

Certain financial assets and liabilities are recorded at fair value. The carrying amount of certain financial instruments, including cash and cash equivalents, accounts receivable, accounts payable and accrued liabilities, approximate fair value due to their relatively short maturities. The carrying amounts of liabilities for the sales of future royalties also approximate their fair value. Assets and liabilities recorded at fair value on a recurring basis in the balance sheets are categorized based upon the level of judgment associated with the inputs used to measure their fair values. Fair value is defined as the exchange price that would be received for an asset or an exit price that would be paid to transfer a liability in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. The authoritative guidance on fair value measurements establishes a three-tier fair value hierarchy for disclosure of fair value measurements as follows:

Level 1—Inputs are unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date;

Level 2—Inputs are observable, unadjusted quoted prices in active markets for similar assets or liabilities, unadjusted quoted prices for identical or similar assets or liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the related assets or liabilities; and

Level 3—Unobservable inputs that are significant to the measurement of the fair value of the assets or liabilities that are supported by little or no market data.

The Company determines the fair value of its equity investment in Solid Biosciences Inc., or Solid, by using the quoted market prices, which are Level 1 fair value measurements.

The following tables set forth the fair value of the Company’s financial assets and liabilities remeasured on a recurring basis based on the three-tier fair value hierarchy (in millions):


	June 30, 2026
	Level 1		Level 2		Level 3		Total
Financial Assets:
Money market funds	$	60	$	—	$	—	$	60
Corporate bonds		—		275		—		275
Commercial paper		—		4		—		4
U.S. Government Treasury and agency securities		—		32		—		32
Investment in Solid common stock		5		—		—		5
Deferred compensation assets		—		21		—		21
Total financial assets	$	65	$	332	$	—	$	397

Financial Liabilities:
Deferred compensation liabilities	$	—	$	21	$	—	$	21


	December 31, 2025
	Level 1		Level 2		Level 3		Total
Financial Assets:
Money market funds	$	320	$	—	$	—	$	320
Time deposits		—		10		—		10
Corporate bonds		—		263		—		263
Commercial paper		—		37		—		37
U.S. Government Treasury and agency securities		12		23		—		35
Investment in Solid common stock		3		—		—		3
Deferred compensation assets		—		19		—		19
Total financial assets	$	335	$	352	$	—	$	687

Financial Liabilities:
Deferred compensation liabilities	$	—	$	19	$	—	$	19

License and Research Agreements - Kyowa Kirin Co., Ltd. - Additional Information (Details) - License Agreement - USD ($) $ in Millions		1 Months Ended	6 Months Ended
	Jul. 01, 2022	Nov. 30, 2025	Jun. 30, 2026	Dec. 31, 2025
Royalty Revenue in European Territory
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Percentage of royalty on net sales receives			10.00%
Kyowa Kirin Collaboration
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Profit loss sharing percentage on net sales			30.00%
Kyowa Kirin Collaboration \| Other Current Assets
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
License agreement other receivables			$ 1	$ 1
Kyowa Kirin Collaboration \| Commercial and Development Activity Reimbursements
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
License agreement accrued liabilities			16	12
Kyowa Kirin Collaboration \| Royalty
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
License agreement accounts receivable			$ 94	$ 98
Kyowa Kirin Collaboration \| Profit Share Territory
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Percentage of right to receive royalty payments on net sales	30.00%	25.00%
Kyowa Kirin Collaboration \| Royalty Revenue in North American Territory \| Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Percentage of royalty on net sales receives			30.00%
Kyowa Kirin Collaboration \| Royalty Revenue in North American Territory \| Minimum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Percentage of royalty on net sales receives			20.00%

Revenue (Tables)

6 Months Ended

Jun. 30, 2026

Revenue from Contract with Customer [Abstract]

Summary of Disaggregation of Total Revenues

The following table disaggregates total revenues from external customers by product sales and royalty revenue (in millions):


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2026		2025		2026		2025
Product sales:
Crysvita	$	54	$	35	$	100	$	90
Dojolvi		27		23		45		40
Evkeeza		21		14		39		25
Mepsevii		10		9		17		17
Total product sales		112		81		201		172
Crysvita royalty revenue		102		86		149		134
Total revenues	$	214	$	167	$	350	$	306

The following table disaggregates total revenues based on geographic location (in millions):


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2026		2025		2026		2025
North America	$	121	$	103	$	180	$	161
Latin America		51		33		93		88
Europe, Middle East, and Africa		35		27		66		50
Asia-Pacific		7		4		11		7
Total revenues	$	214	$	167	$	350	$	306

Net Loss Per Share (Tables)

6 Months Ended

Jun. 30, 2026

Earnings Per Share [Abstract]

Outstanding Shares of Common Stock Equivalents Excluded from Computation of Diluted Net Loss per Share

The following weighted-average outstanding common stock equivalents were excluded from the computation of diluted net loss per share for the periods presented because including them would have been antidilutive:


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
Options to purchase common stock, restricted stock units, and performance stock units		18.2		17.4		16.8		17.0

Stock-Based Awards - Summary of Stock-Based Compensation Expense (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 34	$ 39	$ 64	$ 79
Cost of sales
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	1	1	1	1
Research and development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	18	21	34	42
Selling, general and administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 15	$ 17	$ 29	$ 36

Investment in Amlogenyx Inc. (Tables)

6 Months Ended

Jun. 30, 2026

Investments, All Other Investments [Abstract]

Changes in the Carrying Value of Noncontrolling Interest

Changes in the carrying value of noncontrolling interest for the six months ended June 30, 2026 are as follows (in millions):


	Noncontrolling Interest
As of December 31, 2024	$	7
Changes and adjustments		—
As of December 31, 2025	$	7
Changes and adjustments		—
As of June 30, 2026	$	7

Balance Sheet Components - Additional Information (Details)	6 Months Ended
	Jun. 30, 2026
Maximum
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale securities remaining contractual maturities	3 years

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 320
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

+ Details

License and Research Agreements - Share of Collaboration and Royalty Revenue Related to Crysvita (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Disaggregation Of Revenue [Line Items]
Collaboration and license revenue	$ 214	$ 167	$ 350	$ 306
Royalty revenue
Disaggregation Of Revenue [Line Items]
Collaboration and license revenue	102	86	149	134
Royalty revenue \| Kyowa Kirin Collaboration \| Royalty Revenue in North American Territory
Disaggregation Of Revenue [Line Items]
Collaboration and license revenue	67	55	94	84
Non-cash royalty revenue \| Kyowa Kirin Collaboration \| Royalty Revenue in North American Territory
Disaggregation Of Revenue [Line Items]
Collaboration and license revenue	27	24	39	36
Non-cash royalty revenue \| Kyowa Kirin Collaboration \| Royalty Revenue in European Territory
Disaggregation Of Revenue [Line Items]
Collaboration and license revenue	8	7	16	14
Collaboration and Royalty \| Kyowa Kirin Collaboration
Disaggregation Of Revenue [Line Items]
Collaboration and license revenue	156	121	249	224
Collaboration and Royalty \| Kyowa Kirin Collaboration \| Royalty Revenue in North American Territory
Disaggregation Of Revenue [Line Items]
Collaboration and license revenue	94	79	133	120
Product sales
Disaggregation Of Revenue [Line Items]
Collaboration and license revenue	112	81	201	172
Product sales \| Kyowa Kirin Collaboration
Disaggregation Of Revenue [Line Items]
Collaboration and license revenue	$ 54	$ 35	$ 100	$ 90

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details

License and Research Agreements - GeneTx Biotherapeutics LLC - Additional Information (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended	67 Months Ended
	Jun. 30, 2026	Dec. 31, 2024	Jun. 30, 2026
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Regulatory milestone payments achieved		$ 30	$ 9
Future milestones payable	$ 75
GeneTx [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Eligible future milestone payments	85		85
Texas A&M University [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Clinical Milestone Aggregate	1		1
Texas A&M University [Member] \| Maximum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Future contingent milestone payments	23		23
Annual license fee payment	$ 2		$ 2

Insider Trading Arrangements

3 Months Ended

Jun. 30, 2026

Trading Arrangements, by Individual

Material Terms of Trading Arrangement

Item 5. Other Information

During the three months ended June 30, 2026 the following directors and Section 16 officers adopted a Rule 10b5-1 trading arrangement intended to satisfy the affirmative defense conditions of Rule 10b5-1(c).


Name and Title	Date Adopted	Aggregate Number of Shares of Common Stock to be Sold (Subject to Certain Conditions)	Plan End Date
Howard Horn, Executive Vice President, Chief Financial Officer, Corporate Strategy	June 5, 2026	Up to 9,394 shares	June 4, 2027
Theodore Huizenga Senior Vice President and Chief Accounting Officer	June 4, 2026	Up to 4,726 shares	January 31, 2027
John Pinion, EVP, Chief Quality Officer and Translational Sciences	May 19, 2026	Up to 19,936 shares	May 18, 2027

Howard Horn [Member]

Trading Arrangements, by Individual

Name

Howard Horn

Title

Executive Vice President, Chief Financial Officer, Corporate Strategy

Rule 10b5-1 Arrangement Adopted

true

June 5, 2026

June 4, 2027

364 days

9,394

Theodore Huizenga [Member]

Trading Arrangements, by Individual

Name

Theodore Huizenga

Title

Senior Vice President and Chief Accounting Officer

Rule 10b5-1 Arrangement Adopted

true

June 4, 2026

January 31, 2027

241 days

4,726

Trading Arrangements, by Individual

Name

John Pinion

Title

EVP, Chief Quality Officer and Translational Sciences

Rule 10b5-1 Arrangement Adopted

true

May 19, 2026

May 18, 2027

364 days

19,936

Equity

6 Months Ended

Jun. 30, 2026

Equity [Abstract]

Equity

11. Equity

At-the-Market Offerings

In February 2024, the Company entered into a Sales Agreement with Cowen and Company, LLC, or Cowen, pursuant to which the Company may offer and sell shares of the Company’s common stock having an aggregate offering proceeds up to $350 million, from time to time, in at-the-market, or ATM, offerings through Cowen. During the three and six months ended June 30, 2026, no shares were sold under the ATM. The Company sold 2.2 million shares under the ATM for net proceeds of $80 million during the three and six months ended June 30, 2025. To date, the Company has sold 2.2 million shares under the ATM for net proceeds of $80 million.

- Definition

The entire disclosure for equity.

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+ Details

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Revenues:
Total revenues	$ 214	$ 167	$ 350	$ 306
Operating expenses:
Cost of sales	34	23	64	52
Research and development	167	165	354	331
Selling, general and administrative	88	87	176	174
Total operating expenses	289	275	594	557
Loss from operations	(75)	(108)	(244)	(251)
Interest income	5	6	11	13
Non-cash interest expense on liabilities for sales of future royalties	(22)	(14)	(43)	(28)
Other income	1	2	1	2
Loss before income taxes	(91)	(114)	(275)	(264)
Provision for income taxes	(1)	(1)	(2)	(2)
Net loss	$ (92)	$ (115)	$ (277)	$ (266)
Net loss per share, basic	$ (0.9)	$ (1.17)	$ (2.73)	$ (2.73)
Net loss per share, diluted	$ (0.9)	$ (1.17)	$ (2.73)	$ (2.73)
Shares used in computing net loss per share, Basic	101.9	98.5	101.3	97.4
Shares used in computing net loss per share, Diluted	101.9	98.5	101.3	97.4
Product sales
Revenues:
Total revenues	$ 112	$ 81	$ 201	$ 172
Royalty revenue
Revenues:
Total revenues	$ 102	$ 86	$ 149	$ 134

Organization

6 Months Ended

Jun. 30, 2026

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Organization

1. Organization

Ultragenyx Pharmaceutical Inc., or the Company, is a biopharmaceutical company incorporated in Delaware.

The Company is focused on the identification, acquisition, development, and commercialization of novel products for the treatment of serious rare and ultra-rare genetic diseases. The Company operates as one reportable segment and has four commercially approved products.

Crysvita® (burosumab) is approved in the United States, or U.S., the European Union, or EU, and certain other regions for the treatment of X-linked hypophosphatemia, or XLH, in adult and pediatric patients one year of age and older. Crysvita is also approved in the U.S. and certain other regions for the treatment of fibroblast growth factor 23, or FGF23-related hypophosphatemia in tumor-induced osteomalacia, or TIO, associated with phosphaturic mesenchymal tumors that cannot be curatively resected or localized in adults and pediatric patients 2 years of age and older.

Mepsevii® (vestronidase alfa) is approved in the U.S., the EU and certain other regions, as the first medicine for the treatment of children and adults with mucopolysaccharidosis VII, or MPS VII, also known as Sly syndrome.

Dojolvi® (triheptanoin) is approved in the U.S. and certain other regions for the treatment of pediatric and adult patients severely affected by long-chain fatty acid oxidation disorders, or LC-FAOD.

Evkeeza® (evinacumab) is approved in the U.S. and the European Economic Area, or EEA, and Japan for the treatment of homozygous familial hypercholesterolemia, or HoFH. The Company has exclusive rights to commercialize Evkeeza® (evinacumab) outside of the U.S.

In addition to the approved products, the Company has the following ongoing clinical development programs:

•

DTX401 is an adeno-associated virus 8, or AAV8, gene therapy product candidate for the treatment of patients with glycogen storage disease type Ia, or GSDIa;

•

UX111 (formerly ABO-102) is an adeno-associated virus 9, or AAV9, gene therapy product candidate for the treatment of patients with Sanfilippo syndrome type A, or MPS IIIA, a rare lysosomal storage disease;

•

GTX-102 is an antisense oligonucleotide, or ASO for the treatment of Angelman syndrome, a debilitating and rare neurogenetic disorder caused by loss-of-function of the maternally inherited allele of the UBE3A gene;

•

DTX301 is an AAV8 gene therapy product candidate in development for the treatment of patients with ornithine transcarbamylase, or OTC deficiency, the most common urea cycle disorder;

•

UX701 is an AAV9 gene therapy designed to deliver stable expression of a truncated version of the ATP7B copper transporter following a single intravenous infusion to improve copper distribution and excretion from the body and reverse pathological findings of Wilson liver disease;

•

UX016 is a small-molecule prodrug of sialic acid, or SA, being evaluated as a substrate replacement therapy for GNE myopathy; and

•

UX143 which is subject to the Company’s collaboration agreement with Mereo BioPharma 3, or Mereo, is a fully human monoclonal antibody that inhibits sclerostin, a protein that acts on a key bone-signaling pathway and inhibits the activity of bone-forming cells for the treatment of patients with Osteogenesis Imperfecta, or OI.

The Company has sustained operating losses and expects such annual losses to continue in the near term. The Company’s ultimate success depends on the outcome of its research and development and commercialization activities. Through June 30, 2026, the Company has relied primarily on the sale of equity securities, revenues from commercial products, the sale of certain future royalties, and strategic collaboration arrangements to finance its operations. The Company may need to raise additional capital to fully implement its business plans through the issuance of equity, borrowings, or strategic alliances with partner companies. However, if such financing is not available at adequate levels, the Company would need to reevaluate its operating plans.

Accumulated Other Comprehensive Loss - Schedule of Total Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Foreign currency translation adjustments	$ 1	$ 1
Unrealized loss on available-for-sale securities	(1)	0
Total accumulated other comprehensive loss	$ 0	$ 1

- Definition

Amount, after tax, of accumulated increase (decrease) in equity from transaction and other event and circumstance from nonowner source.

+ References + Details

Accumulated Other Comprehensive Loss (Tables)

6 Months Ended

Jun. 30, 2026

Other Comprehensive Income (Loss), Net of Tax [Abstract]

Schedule of Total Accumulated Other Comprehensive Loss

Total accumulated other comprehensive loss consisted of the following (in millions):


	June 30,			December 31,
	2026			2025
Foreign currency translation adjustments	$	1		$	1
Unrealized loss on available-for-sale securities		(1	)		—
Total accumulated other comprehensive loss	$	—		$	1

Financial Instruments (Tables)

6 Months Ended

Jun. 30, 2026

Fair Value Disclosures [Abstract]

Summary of Financial Assets Measured on Recurring Basis

The following tables set forth the fair value of the Company’s financial assets and liabilities remeasured on a recurring basis based on the three-tier fair value hierarchy (in millions):


	June 30, 2026
	Level 1		Level 2		Level 3		Total
Financial Assets:
Money market funds	$	60	$	—	$	—	$	60
Corporate bonds		—		275		—		275
Commercial paper		—		4		—		4
U.S. Government Treasury and agency securities		—		32		—		32
Investment in Solid common stock		5		—		—		5
Deferred compensation assets		—		21		—		21
Total financial assets	$	65	$	332	$	—	$	397

Financial Liabilities:
Deferred compensation liabilities	$	—	$	21	$	—	$	21


	December 31, 2025
	Level 1		Level 2		Level 3		Total
Financial Assets:
Money market funds	$	320	$	—	$	—	$	320
Time deposits		—		10		—		10
Corporate bonds		—		263		—		263
Commercial paper		—		37		—		37
U.S. Government Treasury and agency securities		12		23		—		35
Investment in Solid common stock		3		—		—		3
Deferred compensation assets		—		19		—		19
Total financial assets	$	335	$	352	$	—	$	687

Financial Liabilities:
Deferred compensation liabilities	$	—	$	19	$	—	$	19

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Statement of Comprehensive Income [Abstract]
Net loss	$ (92)	$ (115)	$ (277)	$ (266)
Other comprehensive income (loss):
Foreign currency translation adjustments	0	0	0	1
Change in unrealized loss on available-for-sale securities	0	0	(1)	0
Other comprehensive income (loss):	0	0	(1)	1
Total comprehensive loss	$ (92)	$ (115)	$ (278)	$ (265)

- Definition

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References + Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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+ Details

License and Research Agreements - Mereo - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended	67 Months Ended
	Jan. 31, 2021	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2024	Jun. 30, 2026	Dec. 31, 2025
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Research and development		$ 167	$ 165	$ 354	$ 331
Regulatory milestone payments achieved						$ 30	$ 9
License and Collaboration Agreement \| Mereo
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Offset to research and development expense		$ 2	$ 2	$ 2	$ 2
License agreement accounts receivable								$ 1
Payments made under agreement	$ 50

Summary of Significant Accounting Policies - Summary of Reconciliation of Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025	Jun. 30, 2025	Dec. 31, 2024
Accounting Policies [Abstract]
Cash and cash equivalents	$ 125	$ 421	$ 176
Restricted cash included in other current assets	9		9
Restricted cash included in other non-current assets	6		4
Total cash, cash equivalents, and restricted cash shown in the statements of cash flows	$ 140	$ 436	$ 189	$ 184

Revenue - Summary of Disaggregation of Total Revenues from Customers (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Disaggregation Of Revenue [Line Items]
Total revenues	$ 214	$ 167	$ 350	$ 306
Product Revenue
Disaggregation Of Revenue [Line Items]
Total revenues	112	81	201	172
Product Revenue \| Crysvita
Disaggregation Of Revenue [Line Items]
Total revenues	54	35	100	90
Product Revenue \| Dojolvi
Disaggregation Of Revenue [Line Items]
Total revenues	27	23	45	40
Product Revenue \| Evkeeza
Disaggregation Of Revenue [Line Items]
Total revenues	21	14	39	25
Product Revenue \| Mepsevii
Disaggregation Of Revenue [Line Items]
Total revenues	10	9	17	17
Royalty revenue
Disaggregation Of Revenue [Line Items]
Total revenues	102	86	149	134
Royalty revenue \| Crysvita
Disaggregation Of Revenue [Line Items]
Total revenues	$ 102	$ 86	$ 149	$ 134

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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License and Research Agreements - Regeneron - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended	54 Months Ended	67 Months Ended
	Jan. 31, 2022	Dec. 31, 2024	Jun. 30, 2026	Jun. 30, 2026	Dec. 31, 2025
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Regulatory milestone payments achieved		$ 30		$ 9
Regeneron Pharmaceuticals Inc
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Upfront payments of collaboration	$ 30
Regulatory milestone payments achieved			$ 33
Eligible future milestone payments			31	31
Accrued collaboration payables			$ 5	$ 5	$ 9
Maximum \| Regeneron Pharmaceuticals Inc
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Profit loss sharing percentage on net sales	40.00%
Minimum \| Regeneron Pharmaceuticals Inc
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Profit loss sharing percentage on net sales	20.00%

Balance Sheet Components (Tables)

6 Months Ended

Jun. 30, 2026

Investments, Debt and Equity Securities [Abstract]

Summary of Cash Equivalents and Marketable Securities Classified as Available For Sale Securities

The fair values of cash equivalents and marketable securities classified as available-for-sale securities consist of the following (in millions):


	June 30, 2026
				Gross Unrealized
		Amortized Cost		Gains		Losses			Estimated Fair Value
Money market funds		$	60	$	—	$	—		$	60
Corporate bonds			276		—		(1	)		275
Commercial paper			4		—		—			4
U.S. Government Treasury and agency securities			32		—		—			32
Total		$	372	$	—	$	(1	)	$	371


	December 31, 2025
				Gross Unrealized
		Amortized Cost		Gains		Losses		Estimated Fair Value
Money market funds		$	320	$	—	$	—	$	320
Time deposits			10		—		—		10
Corporate bonds			263		—		—		263
Commercial paper			37		—		—		37
U.S. Government Treasury and agency securities			35		—		—		35
Total		$	665	$	—	$	—	$	665

Summary of Inventory

Inventory consists of the following (in millions):


	June 30,		December 31,
	2026		2025
Work-in-process	$	32	$	27
Finished goods		27		25
Total inventory	$	59	$	52

Summary of Accrued Liabilities

Accrued liabilities consist of the following (in millions):


	June 30,		December 31,
	2026		2025
Research and clinical study expenses	$	23	$	23
Payroll and related expenses		63		89
Revenue related reserves		72		57
Manufacturing and related expenses		42		67
Other		21		29
Total accrued liabilities	$	221	$	265

- Definition

Tabular disclosure of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-9

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aaa)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-3

+ Details

Summary of Significant Accounting Policies

6 Months Ended

Jun. 30, 2026

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

Basis of Presentation

The accompanying unaudited Condensed Consolidated Financial Statements include the accounts of the Company and its wholly-owned subsidiaries. The Company consolidates any variable interest entity, or VIE, for which it is the primary beneficiary. Certain reclassifications have been made to prior periods in the Condensed Consolidated Financial Statements and accompanying notes to conform with the current presentation.

The financial statements have been prepared in accordance with U.S. generally accepted accounting principles, or GAAP, for interim financial information and in accordance with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. The unaudited interim Condensed Consolidated Financial Statements have been prepared on the same basis as the annual financial statements. In the opinion of management, the accompanying unaudited Condensed Consolidated Financial Statements reflect all adjustments (consisting only of normal recurring adjustments) considered necessary for a fair presentation. All intercompany accounts and transactions have been eliminated. These financial statements should be read in conjunction with the audited financial statements and notes thereto for the preceding fiscal year contained in the Company’s Annual Report on Form 10-K filed on February 18, 2026, or Annual Report, with the United States Securities and Exchange Commission, or the SEC.

The results of operations for the three and six months ended June 30, 2026 are not necessarily indicative of the results to be expected for the year ending December 31, 2026. The Condensed Consolidated Balance Sheet as of December 31, 2025 has been derived from audited financial statements at that date, but does not include all of the information required by GAAP for complete financial statements.

Segment Reporting

The Company operates as one reportable segment relating to the research, development and commercialization of its products. The segment derives its current revenues from its four commercially approved products.

The Company’s Chief Operating Decision Maker, or CODM, is the Company's Chief Executive Officer. The CODM manages the Company’s operations on an integrated basis for the purpose of allocating resources. When evaluating the Company’s financial performance, the CODM regularly reviews total revenues and total expenses and makes decisions using this information on a consolidated basis.

Use of Estimates

The accompanying Condensed Consolidated Financial Statements have been prepared in accordance with GAAP. The preparation of the Condensed Consolidated Financial Statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent liabilities and the reported amounts of expenses in the Condensed Consolidated Financial Statements and the accompanying notes. On an ongoing basis, management evaluates its estimates, including those related to clinical trial accruals, fair value of assets and liabilities, income taxes, stock-based compensation, revenue recognition, and the liabilities for sales of future royalties. Management bases its estimates on historical experience and on various other market-specific and relevant assumptions that management believes to be reasonable under the circumstances. Actual results could differ from those estimates.

Cash, Cash Equivalents and Restricted Cash

Restricted cash primarily consists of money market accounts used as collateral for the Company’s obligations under its facility leases and to guarantee the fulfillment of certain sales orders to certain government-sponsored customers. The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the Condensed Consolidated Balance Sheets that sum to the total of the same such amounts shown in the Condensed Consolidated Statement of Cash Flows (in millions):


	June 30,
	2026		2025
Cash and cash equivalents	$	125	$	176
Restricted cash included in other current assets		9		9
Restricted cash included in other non-current assets		6		4
Total cash, cash equivalents, and restricted cash shown in the statements of cash flows	$	140	$	189

Credit Losses

The Company is exposed to credit losses primarily through receivables from customers and collaborators and through its available-for-sale debt securities. For trade receivables and other financial instruments, the Company uses a forward-looking expected loss model that recognizes a current period charge for losses that are expected to be incurred over the life of the financial instrument.

The Company’s expected loss allowance methodology for the receivables is developed using historical collection experience, current and future economic market conditions, a review of the current aging status and financial condition of the entities. Specific allowance amounts are established to record the appropriate allowance for customers that have a higher probability of default. Balances are written off when determined to be uncollectible. The Company’s expected loss allowance methodology for the debt securities is developed by reviewing the extent of the unrealized loss, the size, term, geographical location, and industry of the issuer, the issuers’ credit ratings and any changes in those ratings, as well as reviewing current and future economic market conditions and the issuers’ current status and financial condition. There were no material credit losses recorded for receivables and available-for-sale debt securities which were attributable to credit risk as of June 30, 2026 and December 31, 2025.

Liabilities for Sales of Future Royalties

The Company sold the right to receive certain royalty payments from net sales of Crysvita in certain territories to RPI Finance Trust, or RPI, an affiliate of Royalty Pharma, and to OCM LS23 Holdings LP, an investment vehicle for Ontario Municipal Employees Retirement System, or OMERS, as further described in “Note 8. Liabilities for Sales of Future Royalties.” At inception, the Company recorded a liability based upon estimated future cash flows discounted at a market rate. The liability is amortized using the effective interest method over the estimated life of the applicable arrangement. To determine the amortization of the liability, the Company estimates the total amount of future royalty payments to be received by the Company and paid to RPI and OMERS. Any estimated royalty payments in excess of the initial liability are recorded as non-cash interest expense. Consequently, the Company estimates imputed interest on the unamortized portion of the liabilities and records interest expense based on the estimated term of the arrangements.

The Company periodically assesses the expected royalty payments using a combination of historical results, internal projections and forecasts from external sources. To the extent such payments are greater or less than the Company’s initial estimates or the timing of such payments is materially different than its original estimates, the Company employs the prospective method to adjust the amortization of the liabilities and the effective interest rate.

Revenue Recognition

Product Sales

The Company sells its approved products through a limited number of distributors. Under Accounting Standards Codification, or ASC, 606, Revenue from Contracts with Customers, revenue from product sales is recognized at the point in time when control is transferred to these distributors. The Company also recognizes revenue from sales of certain products on a “named patient” basis, which are allowed in certain countries prior to the commercial approval of the product. Prior to recognizing revenue, the Company makes estimates of the transaction price, including any variable consideration that is subject to a constraint. Amounts of variable consideration are included in the transaction price to the extent that it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur and when the uncertainty associated with the variable consideration is subsequently resolved. Product sales are recorded net of estimated government-mandated rebates and chargebacks, estimated product returns, and other deductions.

Provisions for returns and other adjustments are provided for in the period the related revenue is recorded, as estimated by management. These reserves are based on estimates of the amounts earned or to be claimed on the related sales and are reviewed periodically and adjusted as necessary. The Company’s estimates of government mandated rebates, chargebacks, estimated product returns, and other deductions depend on the identification of key customer contract terms and conditions, as well as estimates of sales volumes to different classes of payors. If actual results vary, the Company may need to adjust these estimates, which could have a material effect on earnings in the period of the adjustment.

Collaboration, License, and Royalty Revenue

The Company has certain license and collaboration agreements that are within the scope of ASC 808, Collaborative Agreements, which provides guidance on the presentation and disclosure of collaborative arrangements. Generally, the classification of the transactions under the collaborative arrangements is determined based on the nature of contractual terms of the arrangement, along with the nature of the operations of the participants. The Company records its share of collaboration revenue, net of transfer pricing related to net sales in the period in which such sales occur, if the Company is considered as an agent in the

arrangement. The Company is considered an agent when the collaboration partner controls the product before transfer to the customers and has the ability to direct the use of and obtain substantially all of the remaining benefits from the product. We generally classify funding received related to research and development services and commercialization costs as a reduction of research and development expenses and selling, general and administrative expenses, respectively, in the Condensed Consolidated Statements of Operations, because the provision of such services for collaborative partners are not considered to be part of the Company’s ongoing major or central operations.

The Company utilizes certain information from its collaboration partners to record collaboration revenue, including revenue from the sale of the product, associated reserves on revenue, and costs incurred for development and sales activities. For the periods covered in the financial statements presented, there have been no material changes to prior period estimates of revenues and expenses. The Company also records royalty revenues under certain of the Company’s license or collaboration agreements in exchange for the license of intellectual property.

As described in “Note 8. Liabilities for Sales of Future Royalties”, for certain royalty payments from net sales of Crysvita in applicable territories that were sold to RPI and OMERS, the Company records the non-cash royalty revenue on a prospective basis in the Condensed Consolidated Statements of Operations over the term of the applicable arrangement.

The terms of the Company’s collaboration and license agreements may contain multiple performance obligations, which may include licenses and research and development activities. The Company evaluates these agreements under ASC 606, Revenue from Contracts with Customers, to determine the distinct performance obligations. The Company analogizes to ASC 606 for the accounting for distinct performance obligations for which there is a customer relationship. Prior to recognizing revenue, the Company makes estimates of the transaction price, including variable consideration that is subject to a constraint. Amounts of variable consideration are included in the transaction price to the extent that it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur and when the uncertainty associated with the variable consideration is subsequently resolved. Total consideration may include nonrefundable upfront license fees, payments for research and development activities, reimbursement of certain third-party costs, payments based upon the achievement of specified milestones, and royalty payments based on product sales derived from the collaboration.

If there are multiple distinct performance obligations, the Company allocates the transaction price to each distinct performance obligation based on its relative standalone selling price. The standalone selling price is generally determined based on the prices charged to customers or using expected cost-plus margin. The Company estimates the efforts needed to complete the performance obligations and recognizes revenue by measuring the progress towards complete satisfaction of the performance obligations using input measures.

Restructuring

Restructuring expense consists primarily of costs associated with exit or disposal activities, including contract terminations, employee terminations, and severance costs. For employee terminations accounted for as ongoing benefit arrangements, the Company recognizes a liability for termination benefits when it is probable that the benefits will be paid and the amounts are reasonably estimable. Contract termination costs and other costs associated with exit or disposal activities are recognized when it is probable that the costs will be incurred, i.e., upon contract termination or when the Company ceases using the rights conveyed by the contract and the amounts are reasonably estimable.

These costs are recorded within operating expenses in the Condensed Consolidated Statements of Operations and the related restructuring liabilities are included in accounts payable and accrued liabilities in the Condensed Consolidated Balance Sheets.

Recent Accounting Pronouncements

In November 2024, the FASB issued ASU 2024-03, Income Statement-Reporting Comprehensive Income-Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses, requiring public entities to disclose additional information about specific expense categories in the notes to the financial statements on an interim and annual basis. ASU 2024-03 is effective for fiscal years beginning after December 15, 2026, and for interim periods beginning after December 15, 2027, with early adoption permitted. The Company is currently evaluating the impact of adopting ASU 2024-03.

Organization - Additional Information (Details)	6 Months Ended
Organization - Additional Information (Details)	Jun. 30, 2026 Segment
Organization And Nature Of Business [Line Items]
Number of reportable segments	1

Balance Sheet Components - Summary of Inventory (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Inventory, Net [Abstract]
Work-in-process	$ 32	$ 27
Finished goods	27	25
Total inventory	$ 59	$ 52

Financial Instruments - Summary of Financial Assets Measured on Recurring Basis (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	$ 397	$ 687
Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	65	335
Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	332	352
Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	60	320
Money Market Funds \| Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	60	320
Time Deposits
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value		10
Time Deposits \| Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value		10
Corporate Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	275	263
Corporate Bonds \| Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	275	263
Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	4	37
Commercial Paper \| Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	4	37
U.S. Government Treasury and Agency Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	32	35
U.S. Government Treasury and Agency Securities \| Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	0	12
U.S. Government Treasury and Agency Securities \| Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	32	23
Investment in Solid common stock
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	5	3
Investment in Solid common stock \| Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	5	3
Deferred Compensation Assets
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	21	19
Deferred Compensation Assets \| Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	21	19
Deferred Compensation Liabilities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	21	19
Deferred Compensation Liabilities \| Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total fair value	$ 21	$ 19

Pay vs Performance Disclosure - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Millions	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Pay vs Performance Disclosure
Net Income (Loss)	$ (92)	$ (115)	$ (277)	$ (266)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

Strategic Restructuring Plan (Tables)

6 Months Ended

Jun. 30, 2026

Restructuring and Related Activities [Abstract]

Summary of restructuring charges and amounts paid or settled

The following table presents the details of the Company’s restructuring charges and amounts paid or settled during the six months ended June 30, 2026 (in millions):


	Employee-Related			Manufacturing Related			Total
Balance as of December 31, 2025	$	—		$	—		$	—
Restructuring expense		8			22			30
Cash settled/ adjustment		(8	)		(22	)		(30	)
Balance as of June 30, 2026	$	—		$	—		$	—

Summary of Total restructuring charges recognized on the Condensed Consolidated Statements of Operations

Total restructuring charges recognized on the Condensed Consolidated Statements of Operations during the three and six months ended June 30, 2026 were as below (in millions):


	Three Months Ended		Six Months Ended
	June 30,		June 30,
	2026		2026
Research and development	$	—	$	28
Selling, general and administrative		—		2
Total restructuring expense	$	—	$	30

Liabilities for Sales of Future Royalties - Schedule of Key Terms and Activity of Sales of Future Royalties - (Parenthetical) (Details) - 2022 OMERS Agreement - US And Canada - Royalty Purchase Agreement $ in Millions	6 Months Ended
	Jun. 30, 2026 USD ($)
Liability For Sale Of Future Royalties [Line Items]
Profit loss sharing percentage on net sales	30.00%
Royalty Agreement Termination Threshold Amount	$ 725

Net Loss Per Share - Outstanding Shares of Common Stock Equivalents Excluded from Computation of Diluted Net Loss per Share (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Options to Purchase Common Stock, RSUs, and PSUs
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Common stock equivalents excluded from computation of diluted net loss per share	18.2	17.4	16.8	17

Balance Sheet Components

6 Months Ended

Jun. 30, 2026

Investments, Debt and Equity Securities [Abstract]

Balance Sheet Components

4. Balance Sheet Components

Cash Equivalents and Marketable Securities

The fair values of cash equivalents and marketable securities classified as available-for-sale securities consist of the following (in millions):


	June 30, 2026
				Gross Unrealized
		Amortized Cost		Gains		Losses			Estimated Fair Value
Money market funds		$	60	$	—	$	—		$	60
Corporate bonds			276		—		(1	)		275
Commercial paper			4		—		—			4
U.S. Government Treasury and agency securities			32		—		—			32
Total		$	372	$	—	$	(1	)	$	371


	December 31, 2025
				Gross Unrealized
		Amortized Cost		Gains		Losses		Estimated Fair Value
Money market funds		$	320	$	—	$	—	$	320
Time deposits			10		—		—		10
Corporate bonds			263		—		—		263
Commercial paper			37		—		—		37
U.S. Government Treasury and agency securities			35		—		—		35
Total		$	665	$	—	$	—	$	665

At June 30, 2026, the remaining contractual maturities of available-for-sale securities were less than three years. The cost of securities sold is based on the specific-identification method. There have been no significant realized gains or losses on available-for-sale securities for the periods presented. All marketable securities with unrealized losses at June 30, 2026 have been in a loss position for less than 12 months or the loss is not material and is temporary in nature.

Inventory

Inventory consists of the following (in millions):


	June 30,		December 31,
	2026		2025
Work-in-process	$	32	$	27
Finished goods		27		25
Total inventory	$	59	$	52

Accrued Liabilities

Accrued liabilities consist of the following (in millions):


	June 30,		December 31,
	2026		2025
Research and clinical study expenses	$	23	$	23
Payroll and related expenses		63		89
Revenue related reserves		72		57
Manufacturing and related expenses		42		67
Other		21		29
Total accrued liabilities	$	221	$	265

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025
Operating activities:
Net loss	$ (277)	$ (266)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	64	78
Amortization of discount on marketable securities, net	(1)	(3)
Depreciation and amortization	16	18
Non-cash royalty revenue	(55)	(50)
Non-cash interest expense on liabilities for sales of future royalties	43	28
Other	(4)	(1)
Changes in operating assets and liabilities:
Accounts receivable	(43)	(3)
Inventory	(7)	(1)
Prepaid expenses and other assets	3	(17)
Accounts payable, accrued, and other liabilities	(33)	(58)
Net cash used in operating activities	(294)	(275)
Investing activities:
Purchase of property, plant, and equipment	(2)	(4)
Purchase of marketable securities	(188)	(16)
Proceeds from sale of marketable securities	38	0
Proceeds from maturities of marketable securities	155	226
Payments for intangible asset	(5)	(15)
Other	(3)	0
Net cash (used in) provided by investing activities	(5)	191
Financing activities:
Proceeds from the issuance of common stock in connection with at-the-market offering, net	0	80
Proceeds from the issuance of common stock under equity plans, net	3	4
Net cash provided by financing activities	3	84
Effect of exchange rate changes on cash	0	5
Net (decrease) increase in cash, cash equivalents and restricted cash	(296)	5
Cash, cash equivalents and restricted cash at beginning of period	436	184
Cash, cash equivalents and restricted cash at end of period	$ 140	$ 189

License and Research Agreements - Schedule of Cost Sharing Payments (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Cost Sharing Payments [Line Items]
Cost of sales	$ 34	$ 23	$ 64	$ 52
Kyowa Kirin Collaboration [Member]
Cost Sharing Payments [Line Items]
Research and development	(1)	(1)	(2)	(2)
Cost of sales	19	12	35	31
Regeneron Pharmaceuticals Inc
Cost Sharing Payments [Line Items]
Cost of sales	$ 6	$ 2	$ 12	$ 5

License and Research Agreements

6 Months Ended

Jun. 30, 2026

Research Grant Agreement [Abstract]

License and Research Agreements

7. License and Research Agreements

Kyowa Kirin Co., Ltd.

In August 2013, the Company entered into a collaboration and license agreement with Kyowa Kirin Co., Ltd., or KKC. Under the terms of this collaboration and license agreement, as amended, the Company and KKC collaborate on the development and commercialization of Crysvita in the field of orphan diseases in the U.S. and Canada, or the North American Territory, and in the European Union, United Kingdom, and Switzerland, or the European Territory, and the Company has the right to develop and commercialize such products in the field of orphan diseases in Mexico and Central and South America, or Latin America.

The collaboration and license agreements are within the scope of ASC 808, which provides guidance on the presentation and disclosure of collaborative arrangements.

Product Sales Revenue for Latin America and Türkiye

The Company is responsible for commercializing Crysvita in Latin America and Türkiye. The Company is considered the principal in these territories as the Company controls the product before it is transferred to the customer. Accordingly, the Company records revenue on a gross basis for the sale of Crysvita once the product is delivered and the risk and title of the product is transferred to the distributor. In Türkiye, KKC has the option to assume responsibility for commercialization efforts.

Transfer Price and Royalties on Product Sales Revenue

Under the collaboration agreement, KKC manufactures and supplies Crysvita, which is purchased by the Company for sales in Latin America and Türkiye. KKC charges the Company a transfer price of 30% of net sales for supply of product to Latin America. The Company also pays to KKC a low single-digit royalty on net sales in Latin America.

Royalty Revenue for Sales in the North American Territory

KKC has commercialization responsibilities for Crysvita in the North American Territory. The Company is entitled to receive a tiered double-digit revenue share from the mid-20% range up to a maximum rate of 30%, which is recorded as royalty revenue as the underlying sales occur.

In July 2022, the Company sold to OMERS its right to receive 30% of the future royalty payments beginning in April 2023, that are due to the Company based on net sales of Crysvita in the U.S. and Canada, subject to a cap. In November 2025, the Company sold to OMERS its right to an additional 25% of the future royalty payments, beginning in January 2028, that are due to the Company based on net sales of Crysvita in the U.S. and Canada, subject to a cap. These agreements are further described in “Note 8. Liabilities for Sales of Future Royalties.”

Royalty Revenue for Sales in the European Territory

KKC has commercial responsibility for Crysvita in the European Territory. The Company is entitled to receive royalties of up to 10% of net sales in the European Territory, which are recorded as royalty revenue as the underlying sales occur. In December 2019, the Company sold its right to receive these royalty payments to Royalty Pharma, effective January 1, 2020, as further described in “Note 8. Liabilities for Sales of Future Royalties.”

Total Crysvita revenue was as follows (in millions):


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
Product sales	$	54	$	35	$	100	$	90
Revenue in North American Territory:
Royalty revenue		67		55		94		84
Non-cash royalty revenue		27		24		39		36
Total revenue in North American Territory		94		79		133		120
Non-cash royalty revenue in European Territory		8		7		16		14
Total Crysvita revenue	$	156	$	121	$	249	$	224

Collaboration Cost Sharing and Payments

Under the collaboration agreement, KKC and the Company share certain development and commercialization costs, and as a result, the Company was reimbursed for these costs and operating expenses were reduced. KKC also receives a transfer price and royalty on net product sales revenue which is recorded in cost of sales. These amounts were recognized in the Company’s Condensed Consolidated Statements of Operations in connection with the collaboration agreement with KKC as follows (in millions):


	Three Months Ended June 30,						Six Months Ended June 30,
	2026			2025			2026			2025
Research and development	$	(1	)	$	(1	)	$	(2	)	$	(2	)
Cost of sales		19			12			35			31

Collaboration Receivable and Payable

The Company had accounts receivable from KKC in the amount of $94 million and $98 million from royalties, other receivables of $1 million and $1 million recorded in other current assets, and accrued liabilities of $16 million and $12 million from amounts owed for transfer price and royalties as well as commercial and development activity reimbursements, as of June 30, 2026 and December 31, 2025, respectively.

Regeneron

In January 2022, the Company entered into a collaboration with Regeneron to commercialize Evkeeza for HoFH outside of the U.S. Pursuant to the terms of the agreement, the Company received the rights to develop, commercialize and distribute the product for HoFH in countries outside of the U.S. The Company paid Regeneron a $30 million upfront payment. As of June 30, 2026, the Company has recognized an aggregate of $33 million for regulatory and sales milestones under the agreement. As these payments are for the Company’s use of intellectual property for Evkeeza for HoFH, they were recorded as intangible assets. The Company is required to pay up to an aggregate of $31 million in the future contingent upon the achievement of certain regulatory and sales milestones. The Company may share in certain costs for global trials led by Regeneron. Additionally, the Company pays Regeneron a product purchase price and royalties on certain revenues.

The collaboration agreement is within the scope of ASC 808 which provides guidance on the presentation and disclosure of collaborative arrangements. As the Company is the principal in sales transactions with the customer, the Company recognizes product sales and cost of sales in the period the related sales occur and the related revenue recognition criteria are met.

Under the collaboration agreement, Regeneron supplies the product and charges the Company a product purchase price from the low 20% range up to 40% on net sales, which is recognized as cost of sales in the Company’s Condensed Consolidated Statement of Operations. The Company also shares certain development and commercialization costs. Amounts recognized in connection with the collaboration agreement with Regeneron were recognized in the Company’s Condensed Consolidated Statements of Operations as follows (in millions):


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
Cost of sales	$	6	$	2	$	12	$	5

The Company had collaboration payables for this arrangement included in accrued liabilities on the Condensed Consolidated Balance Sheets of $5 million and $9 million as of June 30, 2026 and December 31, 2025, respectively.

GeneTx Biotherapeutics LLC

In August 2019, the Company entered into a Program Agreement and a Unitholder Option Agreement with GeneTx Biotherapeutics LLC, or GeneTx, as subsequently amended, or the Option Agreement, to collaborate on the development of GeneTx’s GTX-102, an ASO for the treatment of Angelman syndrome. In July 2022, the Company exercised its option to acquire GeneTx, pursuant to the terms of the Option Agreement. During the year ended December 31, 2024, the Company achieved a $30 million regulatory milestone upon the initiation of the Phase 3 Aspire clinical study for GTX-102. The Company is obligated to pay up to $85 million in additional regulatory approval milestones for the achievement of U.S. and EU product approvals, and up to $75 million in commercial milestone payments based on annual worldwide net product sales, contingent upon the achievement of the milestones. The Company will also pay tiered mid- to high single-digit percentage royalties based on licensed product annual net sales. If the Company receives and resells an FDA priority review voucher, or PRV, in connection with a new drug application approval, GeneTx unitholders are entitled to receive a portion of proceeds from the sale or a cash payment from the Company if the Company chooses to retain the PRV.

As part of the Company's acquisition of GeneTx, the Company assumed a License Agreement with Texas A&M University, or TAMU. The Company recognized an aggregate of $1 million for clinical milestones under the TAMU agreement, and has future obligations up to $23 million for various milestones and a nominal annual license fee that may increase up to a maximum of $2 million. The Company will also pay mid-single-digit percentage royalties based on licensed product annual net sales.

Prior to the achievement of certain development and regulatory milestones, amounts paid towards the milestones are classified as in-process research and development expense, as the acquired in-process research and development intangible asset has not yet reached technological feasibility and has no alternative future use.

Mereo

In December 2020, the Company entered into a License and Collaboration Agreement with Mereo to collaborate on the development of setrusumab and made a payment of $50 million to Mereo on closing of the transaction. As of June 30, 2026, the Company has recognized an aggregate of $9 million for regulatory milestones achieved.

In December 2024, the Company entered into a manufacturing and supply agreement with Mereo where it is responsible for the supply of setrusumab to Mereo in the Mereo territory. Mereo is responsible for reimbursing us for a portion of the manufacturing process development costs as well as future commercial supply costs.

Although Mereo is a VIE, the Company is not the primary beneficiary as it does not have the power to direct the activities that would most significantly impact the economic performance of Mereo. Prior to the achievement of certain development milestones, all consideration paid to Mereo represents rights to potential future benefits associated with Mereo’s in-process research and development activities, which have not reached technological feasibility and have no alternative future use.

The Company recorded offsets to research and development expense under this arrangement of a nominal amount and $2 million for the three and six months ended June 30, 2026, respectively, and $2 million and $2 million for the three and six months ended June 30, 2025, respectively.

The Company had receivables from Mereo in a nominal amount and $1 million recorded in other current assets as of June 30, 2026 and December 31, 2025, respectively.

Other Arrangements

The Company has also entered into several collaborations and/or licensing arrangements in prior periods. Except as disclosed above, there have been no material changes in these arrangements during the three and six months ended June 30, 2026 as compared to those disclosed in "Note 8. License and Research Agreements" to the Consolidated Financial Statements in the Annual Report.

Under the financial terms of these arrangements, the Company may be required to make payments upon achievement of developmental, regulatory, and commercial milestones, which could be significant. Future milestone payments, if any, will be reflected in the financial statements upon the occurrence of the contingent event. In addition, the Company may be required to pay royalties on future sales if products related to these arrangements are commercialized. The payment of these amounts, however, is contingent upon the occurrence of various future events, which have a high degree of uncertainty.

Stock-Based Awards

6 Months Ended

Jun. 30, 2026

Share-Based Payment Arrangement [Abstract]

Stock-Based Awards

9. Stock-Based Awards

As of June 30, 2026, there were 6.5 million shares available under the 2023 Incentive Plan, 6.1 million shares available under the Amended & Restated 2014 Employee Stock Purchase Plan, and 0.6 million shares available under the Employment Inducement Plan for the future issuance of equity awards.

The table below sets forth the stock-based compensation expense for the periods presented (in millions):


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
Cost of sales	$	1	$	1	$	1	$	1
Research and development		18		21		34		42
Selling, general and administrative		15		17		29		36
Total stock-based compensation expense	$	34	$	39	$	64	$	79

Balance Sheet Components - Summary of Accrued Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Payables and Accruals [Abstract]
Research and clinical study expenses	$ 23	$ 23
Payroll and related expenses	63	89
Revenue related reserves	72	57
Manufacturing and related expenses	42	67
Other	21	29
Total accrued liabilities	$ 221	$ 265

Revenue - Summary of Disaggregation of Total Revenues (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Disaggregation Of Revenue [Line Items]
Total revenues	$ 214	$ 167	$ 350	$ 306
North America
Disaggregation Of Revenue [Line Items]
Total revenues	121	103	180	161
Latin America
Disaggregation Of Revenue [Line Items]
Total revenues	51	33	93	88
Europe, Middle East, and Africa
Disaggregation Of Revenue [Line Items]
Total revenues	35	27	66	50
Asia-Pacific
Disaggregation Of Revenue [Line Items]
Total revenues	$ 7	$ 4	$ 11	$ 7

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-5

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 91
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479777/606-10-55-91

Reference 4: http://www.xbrl.org/2003/role/exampleRef
-Topic 606
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-Section 55
-Paragraph 91
-Subparagraph (b)
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Reference 5: http://www.xbrl.org/2003/role/exampleRef
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Reference 6: http://www.xbrl.org/2003/role/exampleRef
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Reference 7: http://www.xbrl.org/2003/role/exampleRef
-Topic 606
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-Paragraph 91
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Reference 8: http://www.xbrl.org/2003/role/exampleRef
-Topic 606
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Reference 9: http://www.xbrl.org/2003/role/exampleRef
-Topic 606
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-Name Accounting Standards Codification
-Section 55
-Paragraph 91
-Subparagraph (g)
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-URI https://asc.fasb.org/1943274/2147479777/606-10-55-91

Investment in Amlogenyx Inc. - Additional Information (Details) - USD ($) shares in Millions, $ in Millions	Jun. 30, 2026	Dec. 31, 2025	Dec. 31, 2024	Jul. 31, 2024
Schedule of Investments [Line Items]
Total assets	$ 1,264	$ 1,532
Total liabilities	1,548	1,605
Noncontrolling interest	$ 7	7	$ 7
Amlogenyx Inc [Member]
Schedule of Investments [Line Items]
Shares received				9.0
Contributed by affiliated entities				$ 7
Total assets		$ 5
Amlogenyx Inc [Member] \| Third-Party Investor [Member]
Schedule of Investments [Line Items]
Estimated fair value				$ 7
Amlogenyx Inc [Member] \| Series seed preferred stock [Member]
Schedule of Investments [Line Items]
Shares received				1.6

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Current assets:
Cash and cash equivalents	$ 125	$ 421
Marketable securities	167	259
Accounts receivable, net	200	158
Inventory	59	52
Prepaid expenses and other assets	55	61
Total current assets	606	951
Property, plant, and equipment, net	235	244
Marketable securities	144	57
Intangible assets, net	172	176
Goodwill	44	44
Other assets	63	60
Total assets	1,264	1,532
Current liabilities:
Accounts payable	39	31
Accrued liabilities	221	265
Liabilities for sales of future royalties	76	69
Other liabilities	15	19
Total current liabilities	351	384
Deferred tax liabilities	30	30
Liabilities for sales of future royalties	1,126	1,147
Other liabilities	41	44
Total liabilities	1,548	1,605
Noncontrolling interest	7	7
Stockholders' deficit:
Preferred stock, par value of $0.001 per share - 25.0 shares authorized; nil outstanding in 2026 and in 2025	0	0
Common stock, par value of $0.001 per share - 250.0 shares authorized; outstanding - 98.6 in 2026 and 96.6 in 2025	0	0
Treasury stock, at cost, 0.3 shares in 2026 and 0.2 shares in 2025	(10)	(8)
Deferred compensation obligation	10	8
Additional paid-in capital	4,518	4,451
Accumulated other comprehensive loss	0	1
Accumulated deficit	(4,809)	(4,532)
Total stockholders' deficit	(291)	(80)
Total liabilities, noncontrolling interest and stockholders' deficit	$ 1,264	$ 1,532

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (DEFICIT)(Unaudited) - USD ($) $ in Millions	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit	Treasury Stock	Deferred Compensation Obligation
Beginning balance at Dec. 31, 2024	$ 255		$ 4,213	$ (1)	$ (3,957)	$ (4)	$ 4
Beginning balance, shares at Dec. 31, 2024		92,500,000
Issuance of common stock in connection with at-the-market offering, net	80		80
Issuance of common stock in connection with at-the-market offering, net, shares		2,200,000
Stock-based compensation	77		77
Issuance of common stock under equity plan awards, net of tax	4		4
Issuance of common stock under equity plan awards, net of tax, shares		1,700,000
Deferred compensation						(4)	4
Other comprehensive income (loss)	1			1
Net Income (Loss)	(266)				(266)
Ending balance at Jun. 30, 2025	151		4,374	0	(4,223)	(8)	8
Ending balance, shares at Jun. 30, 2025		96,400,000
Beginning balance at Mar. 31, 2025	144		4,252		(4,108)	(8)	8
Beginning balance, shares at Mar. 31, 2025		93,900,000
Issuance of common stock in connection with at-the-market offering, net	80		80
Issuance of common stock in connection with at-the-market offering, net, shares		2,200,000
Stock-based compensation	38		38
Issuance of common stock under equity plan awards, net of tax	4		4
Issuance of common stock under equity plan awards, net of tax, shares		300,000
Other comprehensive income (loss)	0
Net Income (Loss)	(115)				(115)
Ending balance at Jun. 30, 2025	151		4,374	0	(4,223)	(8)	8
Ending balance, shares at Jun. 30, 2025		96,400,000
Beginning balance at Dec. 31, 2025	$ (80)		4,451	1	(4,532)	(8)	8
Beginning balance, shares at Dec. 31, 2025	96,600,000	96,600,000
Stock-based compensation	$ 64		64
Issuance of common stock under equity plan awards, net of tax	3		3
Issuance of common stock under equity plan awards, net of tax, shares		2,000,000
Deferred compensation						(2)	2
Other comprehensive income (loss)	(1)			(1)
Net Income (Loss)	(277)				(277)
Ending balance at Jun. 30, 2026	$ (291)		4,518		(4,809)	(10)	10
Ending balance, shares at Jun. 30, 2026	98,600,000	98,600,000
Beginning balance at Mar. 31, 2026	$ (236)		4,481	$ 0	(4,717)	(10)	10
Beginning balance, shares at Mar. 31, 2026		98,300,000
Stock-based compensation	34		34
Issuance of common stock under equity plan awards, net of tax	3		3
Issuance of common stock under equity plan awards, net of tax, shares		300,000
Other comprehensive income (loss)	0
Net Income (Loss)	(92)				(92)
Ending balance at Jun. 30, 2026	$ (291)		$ 4,518		$ (4,809)	$ (10)	$ 10
Ending balance, shares at Jun. 30, 2026	98,600,000	98,600,000

License and Research Agreements (Tables)

6 Months Ended

Jun. 30, 2026

Share of Collaboration and Royalty Revenue Related to Crysvita

Total Crysvita revenue was as follows (in millions):


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
Product sales	$	54	$	35	$	100	$	90
Revenue in North American Territory:
Royalty revenue		67		55		94		84
Non-cash royalty revenue		27		24		39		36
Total revenue in North American Territory		94		79		133		120
Non-cash royalty revenue in European Territory		8		7		16		14
Total Crysvita revenue	$	156	$	121	$	249	$	224

Kyowa Kirin Collaboration [Member]

Schedule of Cost Sharing Payments

These amounts were recognized in the Company’s Condensed Consolidated Statements of Operations in connection with the collaboration agreement with KKC as follows (in millions):


	Three Months Ended June 30,						Six Months Ended June 30,
	2026			2025			2026			2025
Research and development	$	(1	)	$	(1	)	$	(2	)	$	(2	)
Cost of sales		19			12			35			31

Regeneron Pharmaceuticals Inc

Schedule of Cost Sharing Payments


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
Cost of sales	$	6	$	2	$	12	$	5

Strategic Restructuring Plan - Additional Information (Details)	6 Months Ended
	Jun. 30, 2026
Restructuring Cost and Reserve [Line Items]
Restructuring plan, workforce reduction percentage	10.00%

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

Equity - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	Feb. 29, 2024	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Stockholders Equity [Line Items]
Net proceeds from at-the-market offering			$ 80	$ 0	$ 80	$ 80
Open Market Sale
Stockholders Equity [Line Items]
Option to sell common stock aggregate offering price	$ 350
At-the-Market Offerings
Stockholders Equity [Line Items]
Common stock shares sold		0	2,200,000	0	2,200,000	2,200,000

Liabilities for Sales of Future Royalties (Tables)

6 Months Ended

Jun. 30, 2026

Deferred Revenue Disclosure [Abstract]

Schedule of Key Terms and Activity of Sales of Future Royalties

The following table summarizes the key terms and activity to date for these arrangements (in millions except percentages):


Item	2025 OMERS Agreement	2022 OMERS Agreement	2019 RPI Agreement
Agreement counterparty	OMERS	OMERS	RPI
Contract execution date	November 2025	July 2022	December 2019
Upfront payment to Company	$400	$500	$320
Transaction costs	$8	$9	$6
Territories	U.S. and Canada	U.S. and Canada	EU, U.K., and Switzerland
Percentage of royalties sold	25%*	30%	100%
Royalty start date	January 1, 2028	April 1, 2023	January 1, 2020
CAP	$620	$725	$608 prior to Dec 31, 2030 or until aggregate payments reach $800
Royalties earned from inception to June 30, 2026	$—	$246	$144
Effective annual interest rate (as of June 30, 2026)	9.2%	7.3%	5.5%
* In addition, OMERS will continue to receive 30% of Crysvita net sales in the U.S. and Canada following the achievement of $725 million in aggregate payments under the 2022 OMERS Agreement.

Schedule of Activity Within Liability for Sale of Future Royalties

The following table shows the activity within the liability account (in millions):


	Liabilities for Sales of Future Royalties
	OMERS 2025		OMERS 2022			RPI 2019			Total
December 31, 2024	$	—	$	495		$	375		$	870
Net proceeds from sale of future royalties		392		—			—			392
Royalty revenue		—		(79	)		(29	)		(108	)
Non-cash interest expense		6		36			20			62
December 31, 2025		398		452			366			1,216
Royalty revenue		—		(41	)		(16	)		(57	)
Non-cash interest expense		18		15			10			43
June 30, 2026	$	416	$	426		$	360		$	1,202

Summary of Significant Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2026

Accounting Policies [Abstract]

Summary of Reconciliation of Cash, Cash Equivalents and Restricted Cash

The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the Condensed Consolidated Balance Sheets that sum to the total of the same such amounts shown in the Condensed Consolidated Statement of Cash Flows (in millions):


	June 30,
	2026		2025
Cash and cash equivalents	$	125	$	176
Restricted cash included in other current assets		9		9
Restricted cash included in other non-current assets		6		4
Total cash, cash equivalents, and restricted cash shown in the statements of cash flows	$	140	$	189

Stock-Based Awards - Additional Information (Details)	Jun. 30, 2026 shares
Amended & Restated 2014 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share reserved for future issuance	6,100,000
Employment Inducement Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share reserved for future issuance	600,000
2023 Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share reserved for future issuance	6,500,000

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Revenue - Additional Information (Details)	Jun. 30, 2026	Dec. 31, 2025
Customer One
Disaggregation of Revenue [Line Items]
Percentage of gross accounts receivable balance	47.00%	62.00%
Customer Two
Disaggregation of Revenue [Line Items]
Percentage of gross accounts receivable balance	11.00%	4.00%
Customer Three
Disaggregation of Revenue [Line Items]
Percentage of gross accounts receivable balance	10.00%	2.00%

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

Balance Sheet Components - Summary of Cash Equivalents and Marketable Securities Classified as Available For Sale Securities (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 372	$ 665
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(1)	0
Estimated Fair Value	371	665
Money Market Funds
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	60	320
Estimated Fair Value	60	320
Time Deposits
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost		10
Estimated Fair Value		10
Corporate Bonds
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	276	263
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(1)	0
Estimated Fair Value	275	263
Commercial Paper
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	4	37
Estimated Fair Value	4	37
U.S. Government Treasury and Agency Securities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	32	35
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	$ 32	$ 35

Liabilities for Sales of Future Royalties - Additional Information (Details) - 2025 OMERS Agreement $ in Millions	1 Months Ended
	Nov. 30, 2025 USD ($)
Liability For Sale Of Future Royalties [Line Items]
Royalty repurchase option description	Under the 2025 OMERS agreement, OMERS granted the Company an option to repurchase the entire purchased interest, that expires in November 2027, for 1.35 times the purchase price, or $540 million.
Share repurchase expiration date	Nov. 30, 2027
Royalty repurchase amount	$ 540

Document and Entity Information - shares	6 Months Ended
Document and Entity Information - shares	Jun. 30, 2026	Jul. 31, 2026
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2026
Document Fiscal Year Focus	2026
Document Fiscal Period Focus	Q2
Trading Symbol	RARE
Entity Registrant Name	ULTRAGENYX PHARMACEUTICAL INC.
Entity Central Index Key	0001515673
Entity Current Reporting Status	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		98,588,873
Entity Shell Company	false
Entity File Number	001-36276
Entity Tax Identification Number	27-2546083
Entity Address, Address Line One	60 Leveroni Court
Entity Address, City or Town	Novato
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94949
City Area Code	415
Local Phone Number	483-8800
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common Stock, $0.001 par value
Security Exchange Name	NASDAQ
Entity Incorporation, State or Country Code	DE
Document Quarterly Report	true
Document Transition Report	false

Liabilities for Sales of Future Royalties - Schedule of Activity Within Liability Related to Sale of Future Royalties (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2026	Dec. 31, 2025
Liability For Sale Of Future Royalties [Line Items]
Liability for sale of future royalties at beginning of year	$ 1,216	$ 870
Net proceeds from sale of future royalties		392
Royalty revenue	(57)	(108)
Non-cash interest expense	43	62
Liability for sale of future royalties at end of year	1,202	1,216
2025 OMERS Agreement
Liability For Sale Of Future Royalties [Line Items]
Liability for sale of future royalties at beginning of year	398	0
Net proceeds from sale of future royalties		392
Royalty revenue	0	0
Non-cash interest expense	18	6
Liability for sale of future royalties at end of year	416	398
2022 OMERS Agreement
Liability For Sale Of Future Royalties [Line Items]
Liability for sale of future royalties at beginning of year	452	495
Net proceeds from sale of future royalties		0
Royalty revenue	(41)	(79)
Non-cash interest expense	15	36
Liability for sale of future royalties at end of year	426	452
RPI Finance Trust 2019
Liability For Sale Of Future Royalties [Line Items]
Liability for sale of future royalties at beginning of year	366	375
Net proceeds from sale of future royalties		0
Royalty revenue	(16)	(29)
Non-cash interest expense	10	20
Liability for sale of future royalties at end of year	$ 360	$ 366

Summary of Significant Accounting Policies (Policies)

6 Months Ended

Jun. 30, 2026

Accounting Policies [Abstract]

Basis of Presentation

Segment Reporting

Use of Estimates

Cash, Cash Equivalents and Restricted Cash


	June 30,
	2026		2025
Cash and cash equivalents	$	125	$	176
Restricted cash included in other current assets		9		9
Restricted cash included in other non-current assets		6		4
Total cash, cash equivalents, and restricted cash shown in the statements of cash flows	$	140	$	189

Credit Losses

Liabilities for Sales of Future Royalties

Revenue Recognition

Product Sales

Collaboration, License, and Royalty Revenue

Restructuring

Recent Accounting Pronouncements

Investment in Amlogenyx Inc. - Changes in the Carrying Value of Noncontrolling Interest (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2026	Dec. 31, 2025
Investments, All Other Investments [Abstract]
Beginning Balance	$ 7	$ 7
Changes and adjustments	0	0
Ending Balance	$ 7	$ 7

- Definition

Carrying amount, attributable to parent and noncontrolling interests, of an entity's issued and outstanding stock which is not included within permanent equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. Includes stock with a put option held by an ESOP and stock redeemable by a holder only in the event of a change in control of the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Net Loss Per Share

6 Months Ended

Jun. 30, 2026

Earnings Per Share [Abstract]

Net Loss Per Share

10. Net Loss Per Share

Basic net loss per share has been computed by dividing the net loss by the weighted-average number of shares of common stock outstanding, pre-funded warrants, and treasury stock for deferred compensation obligations required to be settled in shares of common stock. Diluted net loss per share is calculated by dividing net loss by the weighted-average number of shares of common stock outstanding, pre-funded warrants, and treasury stock for deferred compensation obligations required to be settled in shares of common stock, and potential dilutive securities outstanding during the period.


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
Options to purchase common stock, restricted stock units, and performance stock units		18.2		17.4		16.8		17.0

Investment in Amlogenyx. Inc.

6 Months Ended

Jun. 30, 2026

Investments, All Other Investments [Abstract]

Investment in Amlogenyx Inc.

6. Investment in Amlogenyx Inc.

In July 2024, the Company contributed certain intellectual property rights to Amlogenyx Inc., or Amlogenyx, a subsidiary of the Company, and received 9.0 million shares of common stock of Amlogenyx. A third-party investor along with one of its affiliated entities, and the Company each contributed $7 million to Amlogenyx and in exchange, each received approximately 1.6 million shares of series seed preferred stock of Amlogenyx. The purpose of Amlogenyx is to pursue the application of the Company’s novel adeno-associated virus, or AAV, gene therapy to treat beta-amyloid disorders and related neurodegenerative diseases.

Amlogenyx was determined to be a VIE and the Company is the primary beneficiary as it has the power to direct the activities that would most significantly impact the economic performance of Amlogenyx, including the performance of R&D activities relating to its sole product candidate. As the primary beneficiary, the Company has consolidated the financial position, results of operations and cash flows of Amlogenyx in its financial statements and all intercompany balances have been eliminated in consolidation. Upon initial consolidation, the non-controlling interest of the third-party investor was recorded at its estimated fair value of $7 million, which is equal to their original investment.

As of June 30, 2026 and December 31, 2025, the Condensed Consolidated Balance Sheets included Amlogenyx assets of a nominal amount and $5 million, respectively. The assets primarily consisted of cash and cash equivalents which may only be used to settle obligations of Amlogenyx.

Noncontrolling interest related to the third-party investment in Amlogenyx is reported on the Condensed Consolidated Balance Sheets in mezzanine equity.

Changes in the carrying value of noncontrolling interest for the six months ended June 30, 2026 are as follows (in millions):


	Noncontrolling Interest
As of December 31, 2024	$	7
Changes and adjustments		—
As of December 31, 2025	$	7
Changes and adjustments		—
As of June 30, 2026	$	7

Strategic Restructuring Plan - Summary of restructuring charges and amounts paid or settled (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2026	Jun. 30, 2026
Restructuring Cost and Reserve [Line Items]
Balance as of December 31, 2025		$ 0
Restructuring expense	$ 0	30
Cash settled/ adjustment		(30)
Balance as of June 30, 2026	0	0
Emplooyee-Related
Restructuring Cost and Reserve [Line Items]
Balance as of December 31, 2025		0
Restructuring expense		8
Cash settled/ adjustment		(8)
Balance as of June 30, 2026	0	0
Manufacturing Related
Restructuring Cost and Reserve [Line Items]
Balance as of December 31, 2025		0
Restructuring expense		22
Cash settled/ adjustment		(22)
Balance as of June 30, 2026	$ 0	$ 0

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details