jazz-20251231

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 10-K

(Mark One)

For the fiscal year ended December 31, 2025

For the transition period from to

Commission File Number: 001-33500

JAZZ PHARMACEUTICALS PUBLIC LIMITED COMPANY

(Exact name of registrant as specified in its charter)

Fifth Floor, Waterloo Exchange

Waterloo Road, Dublin 4, IrelandD04 E5W7

011-353-1-634-7800

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered

Securities registered pursuant to Section 12(g) of the Act:

None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes☒ No ☐

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes ☐No☒

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☒

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b). ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yes ☐ No ☒

The aggregate market value of the voting and non-voting common equity held by non-affiliates of the registrant, as of June 30, 2025, the last business day of the registrant’s most recently completed second fiscal quarter, was approximately $6,250,820,994 based upon the last sale price reported for the registrant’s ordinary shares on such date on The Nasdaq Global Select Market. The calculation of the aggregate market value of voting and non-voting common equity excludes 1,735,946 ordinary shares of the registrant held by executive officers, directors and shareholders that the registrant concluded were affiliates of the registrant on that date. Exclusion of such shares should not be construed to indicate that any such person possesses the power, direct or indirect, to direct or cause the direction of the management or policies of the registrant or that such person is controlled by or under common control with the registrant.

As of February 17, 2026, a total of 61,560,350 ordinary shares, nominal value $0.0001 per share, of the registrant were outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

Certain information required by Part III, Items 10-14 of this Annual Report on Form 10‐K is incorporated by reference to the registrant’s definitive Proxy Statement for the 2026 Annual General Meeting of Shareholders to be filed with the Securities and Exchange Commission pursuant to Regulation 14A. If such Proxy Statement is not filed within 120 days after the end of the registrant’s fiscal year covered by this Annual Report on Form 10‐K, such information will be included in an amendment to this Annual Report on Form 10‐K to be filed within such 120-day period.

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JAZZ PHARMACEUTICALS PLC

2025 ANNUAL REPORT ON FORM 10-K

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Page

PART I

Defined Terms and Products 3

Item 1. Business 11

Item 1A. Risk Factors 41

Item 1B. Unresolved Staff Comments 75

Item 1C. Cybersecurity 75

Item 2. Properties 77

Item 3. Legal Proceedings 77

Item 4. Mine Safety Disclosures 77

PART II

Item 6. Reserved 81

Item 7A. Quantitative and Qualitative Disclosures About Market Risk 105

Item 8. Financial Statements and Supplementary Data 106

Item 9A. Controls and Procedures 106

Item 9B. Other Information 109

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections 109

PART III

Item 10. Directors, Executive Officers and Corporate Governance 109

Item 11. Executive Compensation 109

Item 14. Principal Accountant Fees and Services 110

PART IV

Item 15. Exhibits and Financial Statement Schedules 110

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Defined Terms and Products

Defined terms

We use several terms in this Annual Report on Form 10-K, including but not limited to those that are finance, regulation and disease-state related, as well as names of other companies, which are given below.

Term Description

340B program U.S. Public Health Service’s 340B program

ACA Affordable Care Act

Adare Adare Pharma Solutions LLC

ADR administrative dispute resolution

Aetna Aetna Inc.

AG authorized generic

AI artificial intelligence

Alkermes Alkermes plc

ALL acute lymphoblastic leukemia

Amended Revolving Facility Maturity Date November 26, 2029

AML acute myeloid leukemia

Amneal Amneal Pharmaceuticals LLC

ANDA abbreviated NDA

API active pharmaceutical ingredient

Ascent Ascent Pharmaceuticals, Inc.

ASD ASD Specialty Healthcare LLC

ASP average sales price

ASU Accounting Standards Update

Audit Committee audit committee of our board of directors

Autifony Autifony Therapeutics Limited

Avadel Avadel Pharmaceuticals plc

Axsome Axsome Therapeutics, Inc.

Azur Pharma Azur Pharma Public Limited Company

BLA Biologics License Application

BPCIA Biologics Price Competition and Innovation Act

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Term Description

BTC biliary tract cancers

BTD Breakthrough Therapy designation

Cardinal Cardinal Health, Inc.

CAT Irish capital acquisitions tax

CBD cannabidiol

CDO Chief Digital Officer

Cencora Cencora, Inc. (formerly named AmerisourceBergen Corporation)

cGMP current Good Manufacturing Practices

Chimerix Chimerix, Inc.

Chimerix Acquisition our acquisition of Chimerix on April 21, 2025

Chimerix Common Stock the common stock, par value $0.001 per share, of Chimerix

CHMP Committee for Medicinal Products for Human Use

CISO Chief Information Security Officer

Clinigen Clinigen Group plc

ClpP mitochondrial caseinolytic protease P

CMS U.S. Centers for Medicare & Medicaid Services

CNX Therapeutics CNX Therapeutics Limited

Code U.S. Internal Revenue Code

CODM chief operating decision maker

COG Children’s Oncology Group

ConcERTos Employee Resource Teams

CREATES Creating and Restoring Equal Access To Equivalent Samples Act of 2019

CSA Federal Controlled Substances Act

DDI drug-drug interaction

DEA U.S. Drug Enforcement Administration

DOJ U.S. Department of Justice

DRD2 dopamine D2 receptor

DS Dravet syndrome

DTC Depository Trust Company

EC European Commission

EDS excessive daytime sleepiness

EEA European Economic Area

EMA European Medicines Agency

ESPP Amended and Restated 2007 Employee Stock Purchase Plan

ESSDS Express Scripts Specialty Distribution Services, Inc.

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Term Description

ETASU elements to assure safe use

EU European Union

EURIBOR Euro Inter-Bank Offered Rate

Exchange Act Securities Exchange Act of 1934, as amended

Exchangeable Senior Notes our 2026 Notes and 2030 Notes

FASB Financial Accounting Standards Board

FCP Federal Ceiling Price

FCPA U.S. Foreign Corrupt Practices Act

FDA U.S. Food and Drug Administration

FDCA Federal Food, Drug, and Cosmetic Act

FSS Federal Supply Schedule pricing program

FTC Federal Trade Commission

GDPR EU’s General Data Protection Regulation

GEA gastroesophageal adenocarcinoma

GHB gamma-hydroxybutyric acid

GMP Good Manufacturing Practice

Granules Granules India Limited

GW GW Pharmaceuticals plc

GW Acquisition our acquisition of GW in May 2021

Hatch-Waxman Act Drug Price Competition and Patent Term Restoration Act of 1984

HHS U.S. Department of Health and Human Services

Hikma Hikma Pharmaceuticals PLC

HRSA Health Resources and Services Administration

HSCT post-hematopoietic stem-cell transplantation

HTA health technology assessment

IFNα interferon alpha

IH idiopathic hypersomnia

IM intramuscular

IND investigational NDA

InvaGen InvaGen Pharmaceuticals, Inc.

IPR inter partes review

IPR&D in-process research and development

IRA Inflation Reduction Act of 2022

IRS U.S. Internal Revenue Service

Jazz Jazz Pharmaceuticals plc

Jazz Investments Jazz Investments I Limited

Jazz Ireland Jazz Pharmaceuticals Ireland Limited

Jazz Lux Jazz Financing Lux S.à.r.l.

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Term Description

Jazz Securities Jazz Securities Designated Activity Company

KRAS Kirsten rat sarcoma virus

LBL lymphoblastic lymphoma

LGS Lennox-Gastaut syndrome

Ligand Ligand Pharmaceuticals Incorporated

Lupin Lupin Inc.

MAA Marketing Authorization Application

MAHA Make America Healthy Again

MAPK mitogen-activated protein kinase

McKesson McKesson Corporation

MDS Myelodysplastic Syndrome

MFN Most-Favored-Nation

MWT Maintenance of Wakefulness Test

NDA New Drug Application

New Repurchase Program our share repurchase program announced on July 31, 2024

NHS U.K. National Health Service

NOL net operating loss

Non-FAMP non-federal average manufacturer price

ODE Orphan Drug Exclusivity in the U.S.

OECD Organization for Economic Co-operation and Development

OIG Office of Inspector General of the HHS

OME orphan market exclusivity in the EU

Par Par Pharmaceutical, Inc.

Patheon Patheon Pharmaceuticals Inc., together with its affiliates

Patheon Agreement our Master Manufacturing Services Agreement with Patheon

PBL Porton Biopharma Limited

PBMs pharmacy benefit managers

PDUFA Prescription Drug User Fee Act

Pfenex Pfenex, Inc.

PharmaMar Pharma Mar, S.A.

PRC People's Republic of China

PRSUs Performance-based restricted stock units

PRV priority review voucher

PTAB Patent Trial and Appeal Board of the USPTO

R&D research and development

R/R relapsed/refractory

Redx Redx Pharma plc

REMS risk evaluation and mitigation strategy

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Term Description

RFC Request for Comment

RLD reference listed drug

RSUs restricted stock units

RTOR Real-Time Oncology Review

Saniona Saniona A/S

sBLA supplemental BLA

SCLC small cell lung cancer

SEC U.S. Securities and Exchange Commission

Securities Act Securities Act of 1933, as amended

Siegfried Siegfried USA, LLC and its European affiliates

Simtra Simtra Biopharma Solutions

SmPC Summary of Product Characteristics

sNDA supplemental NDA

Sumitomo Sumitomo Pharma Co., Ltd.

Sunshine provisions Physician Payment Sunshine Act

sVOD severe VOD

Takeda Takeda Pharmaceutical Company Limited

T-DXd trastuzumab deruxtecan

TCA EU-U.K. Trade and Cooperation Agreement

Term SOFR U.S. dollar Secured Overnight Financing Rate

Teva Teva Pharmaceuticals, Inc.

Tricare program Tricare Retail Pharmacy program

Tris Pharma Tris Pharma, Inc.

TSC tuberous sclerosis complex

TSR total shareholder return

U.K. United Kingdom

U.K. Bribery Act U.K. Bribery Act of 2010

U.S. United States of America

U.S. GAAP U.S. generally accepted accounting principles

USPTO U.S. Patent and Trademark Office

VA U.S. Department of Veterans Affairs

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Term Description

VOD veno-occlusive disease

WAC Wholesale Acquisition Cost

WCLC World Conference on Lung Cancer

Werewolf Werewolf Therapeutics, Inc.

WuXi WuXi Biologics Co., Ltd.

WuXi (Hong Kong) WuXi Biologics (Hong Kong) Limited

XLp XL-protein GmbH

Zymeworks Zymeworks Inc.

Products

The brand names of our products, our delivery devices and certain of our product candidates and their associated generic names are given below.

Term Description

CombiPlex CombiPlex® (delivery technology platform)

Defitelio Defitelio® (defibrotide sodium), Defitelio® (defibrotide)

Modeyso ModeysoTM (dordaviprone)

Sativex* Sativex® (nabiximols) oral solution

Xyrem Xyrem® (sodium oxybate) oral solution

Xywav Xywav® (calcium, magnesium, potassium, and sodium oxybates) oral solution

Zepzelca Zepzelca® (lurbinectedin)

Ziihera Ziihera® (zanidatamab-hrii)

*On October 31, 2025, we completed the sale of Sativex to CNX Therapeutics.

We own or have rights to various copyrights, trademarks, and trade names used in our business in the U.S. and/or other countries, including the following: Jazz Pharmaceuticals®, Xywav® (calcium, magnesium, potassium, and sodium oxybates) oral solution, Xyrem® (sodium oxybate) oral solution, Epidiolex® (cannabidiol) oral solution, Epidyolex® (the trade name in Europe and other countries outside the U.S. for Epidiolex), Rylaze® (asparaginase erwinia chrysanthemi (recombinant)-rywn), Enrylaze® (the trade name in Europe and other countries outside the U.S. and Canada for Rylaze), Zepzelca® (lurbinectedin), Defitelio® (defibrotide sodium), Defitelio® (defibrotide), Vyxeos® (daunorubicin and cytarabine) liposome for injection, Vyxeos® liposomal 44 mg/100 mg powder for concentrate for solution for infusion, ModeysoTM (dordaviprone), CombiPlex® and Ziihera® (zanidatamab-hrii).

This Annual Report on Form 10‐K also includes trademarks, service marks and trade names of other companies. Trademarks, service marks and trade names appearing in this Annual Report on Form 10‐K are the property of their respective owners.

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Annual Report on Form 10‐K contains forward-looking statements within the meaning of Section 27A of the Securities Act, and Section 21E of the Exchange Act, which are subject to the “safe harbor” created by those sections. Forward-looking statements are based on our management’s beliefs and assumptions and on information currently available to our management. In some cases, you can identify forward-looking statements by terms such as “may,” “will,” “should,” “could,” “would,” “expect,” “plan,” “anticipate,” “believe,” “estimate,” “opportunity,” “project,” “predict,” “propose,” “intend,” “continue,” “potential,” “possible,” “strive,” “seek,” “designed,” “goal”, “foreseeable,” “likely” or the negative of these words or other similar expressions intended to identify forward-looking statements. These statements involve known and unknown risks, uncertainties and other factors which may cause our actual results, performance, time frames or achievements to be materially different from any future results, performance, time frames or achievements expressed or implied by the forward-looking statements. We discuss many of these risks, uncertainties and other factors in greater detail under Risk Factors in Part I, Item 1A of this Annual Report on Form 10‐K. Given these risks, uncertainties and other factors, you should not place undue reliance on these forward-looking statements. In addition, our goals and objectives are aspirational and are not guarantees or promises that such goals and objectives will be met. Also, these forward-looking statements represent our estimates and assumptions only as of the date of this filing. You should read this Annual Report on Form 10‐K completely and the documents that we file with the SEC with the understanding that our actual future results may be materially different from what we expect. We hereby qualify our forward-looking statements by our cautionary statements. Except as required by law, we assume no obligation to update our forward-looking statements publicly, or to update the reasons that actual results could differ materially from those anticipated in these forward-looking statements, even if new information becomes available in the future.

SUMMARY RISK FACTORS

Below is a summary of principal factors that make an investment in our ordinary shares speculative or risky. Importantly, this summary does not address all of the risks and uncertainties that we face. Additional discussion of the risks and uncertainties summarized in this risk factor summary, as well as other risks and uncertainties that we face, can be found under “Risk Factors” in Part I, Item 1A of this Annual Report on Form 10‐K, which you should carefully review and consider as part of your evaluation of an investment in our ordinary shares. The below risk factor summary is qualified in its entirety by that more complete discussion of such risks and uncertainties.

•Our inability to maintain revenues from our oxybate franchise would have a material adverse effect on our business, financial condition, results of operations and growth prospects.

•The introduction of new products in the U.S. market that compete with, or otherwise disrupt the market for, our oxybate products has adversely affected and may continue to adversely affect sales of our oxybate products.

•The distribution and sale of our oxybate products are subject to significant regulatory restrictions, including the requirements of a REMS and safety reporting requirements, and these regulatory and safety requirements subject us to risks and uncertainties, any of which could negatively impact sales of Xywav and Xyrem.

•Our inability to maintain or increase sales of Epidiolex/Epidyolex would have a material adverse effect on our business, financial condition, results of operations and growth prospects.

•While we expect Xywav and Epidiolex/Epidyolex to remain our largest products, our success also depends on our ability to effectively commercialize our other existing products and potential future products.

•We face substantial competition from other companies, including companies with larger sales organizations and more experience working with large and diverse product portfolios, and competition from generic drugs.

•Adequate coverage and reimbursement from third party payors may not be available for our products and we may be unable to successfully contract for coverage from PBMs and other organizations; conversely, to secure coverage from these organizations, we may be required to pay rebates or other discounts or other restrictions to reimbursement, either of which could diminish our sales or adversely affect our ability to sell our products profitably.

•The pricing of pharmaceutical products has come under increasing scrutiny as part of a global trend toward healthcare cost containment and resulting changes in healthcare law and policy, including changes to Medicare, may impact our business in ways that we cannot currently predict, which could have a material adverse effect on our business and financial condition.

•In addition to access, coverage and reimbursement, the commercial success of our products depends upon their market acceptance by physicians, patients, third party payors and the medical community.

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•Delays or problems in the supply of our products for sale or for use in clinical trials, loss of our single source suppliers or failure to comply with manufacturing regulations could materially and adversely affect our business, financial condition, results of operations and growth prospects.

•Global trade issues and changes in and uncertainties with respect to trade policies and export regulations, including import and export license requirements, trade sanctions, tariffs and international trade disputes, could increase our costs, reduce the competitiveness of our products and otherwise have a material adverse effect on our business, financial condition, results of operations and growth prospects.

•We may not realize the anticipated benefits from our acquisition of Chimerix.

•Our future success depends on our ability to successfully obtain and maintain regulatory approvals for our late-stage product candidates and, if approved, to successfully launch and commercialize those product candidates.

•We may not be able to successfully identify and acquire or in-license additional products or product candidates to grow our business, and, even if we are able to do so, we may otherwise fail to realize the anticipated benefits of these transactions.

•Conducting clinical trials is costly and time-consuming, and the outcomes are uncertain. A failure to prove that our product candidates are safe and effective in clinical trials, or to generate data in clinical trials to support expansion of the therapeutic uses for our existing products, could materially and adversely affect our business, financial condition, results of operations and growth prospects.

•It is difficult and costly to protect our proprietary rights, and we may not be able to ensure their protection.

•We have incurred, and may in the future incur, substantial costs as a result of litigation or other proceedings relating to patents, other intellectual property rights and related matters, and we may be unable to protect our rights to, or commercialize, our products.

•Significant disruptions of information technology systems or data security incidents could adversely affect our business.

•We are subject to significant ongoing regulatory obligations and oversight, which may subject us to civil or criminal proceedings, investigations, or penalties and may result in significant additional expense and limit our ability to commercialize our products.

•If we fail to comply with our reporting and payment obligations under the Medicaid Drug Rebate Program or other governmental pricing programs, we could be subject to additional reimbursement requirements, penalties, sanctions and fines, which could have a material adverse effect on our business, financial condition, results of operations and growth prospects.

•We have incurred substantial debt, which could impair our flexibility and access to capital and adversely affect our financial position, and our business would be adversely affected if we are unable to service our debt obligations.

•To continue to grow our business, we will need to commit substantial resources, which could result in future losses or otherwise limit our opportunities or affect our ability to operate and grow our business.

•If we fail to attract, retain and motivate members of our executive management team and key personnel, our operations and our future growth may be adversely affected.

NOTE REGARDING COMPANY REFERENCE

In this Annual Report on Form 10-K, unless otherwise indicated or the context otherwise requires, all references to “Jazz Pharmaceuticals,” “Jazz,” “the registrant,” “we,” “us,” and “our” refer to Jazz Pharmaceuticals plc and its consolidated subsidiaries.

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PART I

Item 1.Business

Overview

Jazz Pharmaceuticals plc is a global biopharmaceutical company whose purpose is to innovate to transform the lives of patients and their families. We are dedicated to developing life-changing medicines for people with rare disease – often with limited or no therapeutic options. We have a diverse portfolio of medicines, including leading therapies addressing epilepsies, cancers and sleep disorders. Our patient-focused and science-driven approach powers pioneering R&D advancements across our robust pipeline of innovative therapeutics.

Our lead marketed products, listed below, are approved in countries around the world to improve patient care.

•Xywav® (calcium, magnesium, potassium, and sodium oxybates) oral solution, a product approved by FDA in July 2020, and launched in the U.S. in November 2020 for the treatment of cataplexy or EDS in patients seven years of age and older with narcolepsy, and also approved by FDA in August 2021 for the treatment of IH in adults and launched in the U.S. in November 2021. Xywav contains 92% less sodium than Xyrem®. Xywav is also approved in Canada for the treatment of cataplexy in patients with narcolepsy.

•Epidiolex® (cannabidiol) oral solution, a product approved by FDA and launched in the U.S. in 2018 by GW and currently indicated for the treatment of seizures associated with LGS, DS, or TSC in patients one year of age or older; in the EU and Great Britain (where it is marketed as Epidyolex®) and other markets, it is approved for adjunctive treatment of seizures associated with LGS or DS, in conjunction with clobazam (EU and Great Britain only), in patients 2 years of age and older and for adjunctive treatment of seizures associated with TSC in patients 2 years of age and older.

•Ziihera® (zanidatamab-hrii), a product approved by FDA in November 2024 under FDA’s accelerated approval pathway and launched in the U.S. in December 2024 for the treatment of adults with previously treated, unresectable or metastatic HER2-positive (IHC3+) BTC, as detected by an FDA-approved test. In June 2025, the EC granted conditional marketing authorization for Ziihera for the treatment of adults with unresectable locally advanced or metastatic HER2-positive (IHC3+) BTC previously treated with at least one prior line of systemic therapy. In January 2026, Ziihera obtained conditional approval in Canada for the treatment of adults with previously treated, unresectable locally advanced or metastatic HER2-positive (IHC3+) BTC, as monotherapy.

•ModeysoTM (dordaviprone), a product approved by FDA in August 2025 under FDA's accelerated approval pathway for the treatment of adult and pediatric patients 1 year of age and older with diffuse midline glioma harboring an H3 K27M mutation with progressive disease following prior therapy.

•Zepzelca® (lurbinectedin), a product approved by FDA in June 2020 under FDA's accelerated approval pathway and launched in the U.S. in July 2020 for the treatment of adult patients with metastatic SCLC with disease progression on or after platinum-based chemotherapy; approved by FDA in October 2025 in combination with atezolizumab or atezolizumab and hyaluronidase-tqjs as a first-line maintenance treatment for adults with extensive-stage SCLC whose disease has not progressed after first-line induction therapy with atezolizumab, carboplatin and etoposide; and obtained conditional approval in Canada in September 2021 for the treatment of adults with Stage III or metastatic SCLC, who have progressed on or after platinum-containing therapy.

•Rylaze® (asparaginase erwinia chrysanthemi (recombinant)-rywn), a product approved by FDA in June 2021 and launched in the U.S. in July 2021 for use as a component of a multi-agent chemotherapeutic regimen for the treatment of ALL or LBL in adults and pediatric patients aged one month or older who have developed hypersensitivity to E. coli-derived asparaginase. In September 2023, the EC granted marketing authorization under the trade name Enrylaze®. This therapy is also approved in markets including Great Britain, Canada, Switzerland and Australia.

We continue to invest in pipeline programs that further our rare disease strategy. For a summary of our ongoing R&D activities, see “Business—Research and Development Progress” in this Part I, Item 1.

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Our Strategy

Our strategy for growth is rooted in executing commercial launches and ongoing commercialization initiatives, advancing robust R&D programs and delivering impactful clinical results, effectively deploying capital to strengthen the prospects of achieving our short- and long-term goals through strategic corporate development, and delivering strong financial performance. We focus on rare diseases, which often have high unmet needs and small patient populations, resulting in efficient, concentrated call points. We seek to identify and develop highly differentiated therapies for these patients that we expect will be long-lived assets and that we can support with an efficient commercialization model. In addition, we leverage our efficient, scalable operating model and integrated capabilities across our global infrastructure to effectively reach patients around the world.

Our strategy to deliver sustainable growth and enhanced value continues to be focused on:

•Strong commercial execution to drive diversified revenue growth and address unmet medical needs of our patients who often have limited or no therapeutic options;

•Expanding and advancing our pipeline to achieve a valuable portfolio of durable, highly differentiated products;

•Building an efficient and productive development engine to identify and progress early-, mid- and late-stage assets;

•Identifying and acquiring novel product candidates and approved therapies to complement our existing pipeline and commercial portfolio;

•Investing in an efficient, scalable operating model and differentiated capabilities to enable growth; and

•Unlocking further value through indication expansion and entry into global markets.

Our Commercialized Products

Our Rare Sleep Products. We are the leader in the development and commercialization of oxybate therapy for patients with rare sleep disorders. In 2020, we received FDA approval for Xywav for the treatment of cataplexy or EDS in patients seven years of age and older with narcolepsy. In August 2021, Xywav became the first and only therapy approved by FDA for the treatment of IH in adults. Xywav has become a standard of care for patients with narcolepsy and IH.

Xywav. In July 2020, FDA approved Xywav for the treatment of cataplexy and EDS in patients seven years of age and older with narcolepsy. Narcolepsy is a chronic, debilitating neurological disorder characterized by EDS and the inability to regulate sleep-wake cycles normally. Since there is no cure for narcolepsy and long-term disease management is needed, we believe that Xywav represents an important therapeutic option for patients with this sleep disorder. Narcolepsy affects an estimated one in 2,000 people in the U.S., with symptoms typically appearing in childhood. There are five primary symptoms of narcolepsy, including EDS, cataplexy, disrupted nighttime sleep, sleep-related hallucinations, and sleep paralysis. While patients with narcolepsy may not experience all five symptoms, EDS, an essential symptom of narcolepsy, is present in all narcolepsy patients and is characterized by chronic, pervasive sleepiness as well as sudden irresistible and overwhelming urges to sleep (inadvertent naps and sleep attacks). Narcolepsy may affect many areas of life, including limiting a patient’s education and employment opportunities, and may lead to difficulties at work, school, or in daily life activities like driving, operating machinery or caring for children. Patients with narcolepsy may also suffer from significant medical comorbidities in both adult and pediatric populations, including increased psychiatric comorbidity (including anxiety disorders and mood disorders), intentional self-injury, attempted suicide, suicide-related mortality, other sleep disorders (such as periodic limb movement disorder), cardiovascular disorders (such as hypertension, coronary atherosclerosis, acute myocardial infarction, and congestive heart failure), and metabolic disorders (such as obesity, metabolic syndrome and diabetes).

Cataplexy, the sudden loss of muscle tone with retained consciousness, can be one of the most debilitating symptoms of narcolepsy. Cataplexy is present in approximately 70% of patients with narcolepsy. Cataplexy can range from slight weakness or a drooping of facial muscles to the complete loss of muscle tone resulting in postural collapse. It may also impair a patient’s vision or speech. Cataplexy is often triggered by strong emotions such as laughter, anger or surprise. Cataplexy can severely impair a patient’s quality of life and ability to function.

Narcolepsy patients, by virtue of their diagnosis, are at increased risk of cardiovascular events and disease, and the impact of sodium on cardiovascular health is well established. There is also extensive scientific evidence that reducing sodium consumption, which is a modifiable risk factor, is associated with clinically meaningful reductions in blood pressure and cardiovascular disease risk. Therefore, we believe that reducing sodium intake compared to currently-marketed high-sodium oxybate products by 92% each day is a significant advancement for these patients. The 92% reduction of sodium translates into a reduction of approximately 1,000 to 1,500 milligrams per day for a patient prescribed high-sodium oxybate, depending on the dose. Our commercial efforts are focused on educating patients and physicians about the lifelong impact of high sodium intake, and how the use of Xywav enables them to address what is a modifiable risk factor. When patients transition from Xyrem to Xywav, Xywav treatment is initiated at the same dose and regimen (gram for gram) and titrated as needed based on efficacy and tolerability.

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We view the continued adoption of Xywav in narcolepsy as a positive indication that physicians and patients appreciate the benefits of a low-sodium oxybate option. In June 2021, FDA recognized seven years of ODE for Xywav in EDS and cataplexy in narcolepsy through July 21, 2027 (which was subsequently extended to January 21, 2028). Nevertheless, Lumryz, a fixed-dose, high-sodium oxybate, was approved by FDA on May 1, 2023 for the treatment of cataplexy or EDS in adults with narcolepsy and was launched in the U.S. market in June 2023. FDA continues to recognize seven years of ODE for Xywav in narcolepsy. In connection with granting ODE for Xywav, FDA stated that “Xywav is clinically superior to Xyrem by means of greater safety because Xywav provides a greatly reduced chronic sodium burden compared to Xyrem.” FDA's summary also stated that “the differences in the sodium content of the two products at the recommended doses will be clinically meaningful in reducing cardiovascular morbidity in a substantial proportion of patients for whom the drug is indicated.” FDA has also recognized that the difference in sodium content between Xywav and Lumryz is likely to be clinically meaningful in all patients with narcolepsy and that Xywav is safer than Lumryz in all such patients. Lumryz has the same sodium content as Xyrem. Our first medicine in rare sleep disorders was Xyrem, which contains 1640mg of sodium per 9-gram dose per night. Xyrem is indicated for the treatment of cataplexy and EDS in patients seven years of age and older with narcolepsy. Xywav contains 92% less sodium than Xyrem and is the only approved oxybate therapy that does not carry a warning and precaution related to high sodium intake.

On August 12, 2021, FDA approved Xywav for the treatment of IH in adults. Xywav remains the first and only FDA-approved therapy to treat IH. We initiated the U.S. commercial launch of Xywav for the treatment of IH in adults on November 1, 2021. In January 2022, FDA recognized seven years of ODE for Xywav in IH through August 12, 2028. IH is a debilitating neurologic sleep disorder characterized by chronic EDS (the inability to stay awake and alert during the day resulting in the irrepressible need to sleep or unplanned lapses into sleep or drowsiness), severe sleep inertia, and prolonged and non-restorative nighttime sleep. Although there are overlapping clinical features with other conditions, including narcolepsy, IH has its own specific diagnostic criteria. IH can significantly affect social, educational and occupational functioning. An estimated 37,000 people in the U.S. have been diagnosed with IH and are actively seeking healthcare.

We have agreements in place for Xywav with all three major PBMs in the U.S. To date, we have entered into agreements with various entities and have achieved benefit coverage for Xywav in both narcolepsy and IH indications for approximately 90% of commercial lives.

We have seen strong adoption of Xywav in narcolepsy since its launch in November 2020 and increasing adoption in IH since its launch in November 2021. At the end of 2025, there were approximately 16,175 patients taking Xywav, including approximately 10,950 patients with narcolepsy and approximately 5,225 patients with IH.

In 2025, net product sales of Xywav were $1,657.0 million, which represented 41% of our total net product sales for the year.

Xyrem. Xyrem was approved in the U.S. for the treatment of cataplexy in patients with narcolepsy in 2002 and was approved for treatment of EDS in patients with narcolepsy in 2005. In October 2018, Xyrem was also approved in the U.S. for the treatment of cataplexy or EDS in pediatric patients seven years of age and older with narcolepsy. As of January 2026, we are aware of two high-sodium oxybate generics of Xyrem that have been launched.

In 2025, net product sales of Xyrem were $146.0 million, which represented 4% of our total net product sales for the year.

Xywav and Xyrem REMS. Our marketing, sales and distribution of Xywav and Xyrem in the U.S. are subject to a REMS, which is required by FDA to mitigate the risks of serious adverse outcomes resulting from inappropriate prescribing, abuse, misuse and diversion of Xywav and Xyrem. The Xywav and Xyrem REMS has the same requirements for both products. Under this REMS, all of the Xywav and Xyrem sold in the U.S. must be dispensed and shipped directly to patients or caregivers through a central pharmacy. Xywav and Xyrem may not be stocked in retail pharmacies. Physicians and patients must complete an enrollment process prior to fulfillment of Xywav and Xyrem prescriptions, and each physician and patient must receive materials concerning the serious risks associated with Xywav and Xyrem before the physician can prescribe, or a patient can receive, the product. The central certified pharmacy must monitor and report instances of patient or prescriber behavior giving rise to a reasonable suspicion of abuse, misuse or diversion of Xywav and Xyrem, and maintains enrollment and prescription monitoring information in a central database. The central pharmacy ships the product directly to the patient (or caregiver) by a courier service.

Since 2002, we have had exclusive agreements with ESSDS, the central pharmacy for Xywav and Xyrem, to distribute Xywav and Xyrem in the U.S. and provide patient support services related to Xyrem. In December 2022, we entered into new agreements with ESSDS with a two-year term and our ability to extend the term for an additional year. Our current agreements with ESSDS were amended in November 2025 to extend the term of the central pharmacy agreement to December 31, 2026, and the patient support services agreement to September 1, 2026. The agreements may be terminated by either party at any time without cause on 180 days’ prior written notice to the other party.

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Our Rare Epilepsy Product

Epidiolex. We acquired Epidiolex (Epidyolex outside the U.S.) in May 2021 as part of our GW Acquisition, which added a durable and long-lived asset in rare epilepsies to our portfolio. Epidiolex was approved in the U.S. in June 2018 for the treatment of seizures associated with two rare and severe forms of epilepsy, LGS and DS, in patients two years of age and older, and subsequently approved in July 2020 for the treatment of seizures associated with TSC in patients one year of age and older. FDA also approved the expansion of the other approved indications, LGS and DS, to patients one year of age and older. In September 2019, the EC granted marketing authorization under the trade name Epidyolex for use as adjunctive therapy of seizures associated with LGS or DS, in conjunction with clobazam, for patients two years of age and older. The clobazam restriction is limited to the EU and Great Britain. Epidyolex was also approved for adjunctive therapy in seizures associated with TSC for patients 2 years of age and older in the EU in April 2021 and Great Britain in August 2021. Epidyolex is now launched and reimbursed in more than 40 countries. See “Research and Development Progress” below for a discussion of clinical development activities for Epidiolex.

LGS and DS are severe childhood-onset, drug-resistant epilepsy syndromes. LGS and DS affect approximately 35,000-50,000 and approximately 10,000 individuals in the U.S., respectively. TSC is a rare genetic disorder that causes non-malignant tumors to form in many different organs and is a leading cause of genetic epilepsy. TSC affects approximately 50,000 individuals in the U.S. Epidiolex has received ODE to treat seizures associated with TSC, which expires in July 2027. From October 2023 through January 2025, we entered into settlement agreements with each of the Epidiolex ANDA Filers that resolved our patent litigation with them related to Epidiolex. Under the settlement agreements, we granted each of the Epidiolex ANDA Filers a license to manufacture, market, and sell its own generic version of Epidiolex beginning in the very late 2030s, or earlier under certain circumstances, including but not limited to the launch of another generic Epidiolex product or a final decision that all unexpired claims of the Epidiolex patents are not infringed, or are invalid and/or unenforceable.

Net product sales of Epidiolex/Epidyolex in 2025 were$1,059.2 million, which represented 26% of our total net product sales for the year.

Our Rare Oncology Products

Ziihera. We acquired our exclusive development and commercialization rights to Ziihera in 2022 through an exclusive licensing and collaboration agreement with a subsidiary of Zymeworks providing development and commercialization rights to zanidatamab across all indications in the U.S., Europe, Japan and all other territories except for those Asia/Pacific territories previously licensed by Zymeworks. The term of the license agreement extends on a licensed product-by-licensed product and country-by-country basis until the expiration of the royalty term for such licensed product in such country. We have the right to terminate the license agreement at will upon a specified notice period, and either party can terminate the license agreement for the other party’s uncured material breach or bankruptcy.

Ziihera is a bispecific HER2-directed antibody that binds to two extracellular sites on HER2. Binding of zanidatamab-hrii with HER2 results in internalization leading to a reduction of the receptor on the tumor cell surface. In the U.S., Ziihera was granted accelerated approval by FDA in November 2024 and is indicated for the treatment of adults with previously treated, unresectable or metastatic HER2-positive (IHC3+) BTC, as detected by an FDA-approved test. Ziihera was launched in December 2024. Continued approval for BTC may be contingent upon verification and description of clinical benefit in the Phase 3 HERIZON-BTC-302 confirmatory trial.

In June 2025, the EC granted conditional marketing authorization for Ziihera for the treatment of adults with unresectable locally advanced or metastatic HER2-positive (IHC3+) BTC previously treated with at least one prior line of systemic therapy. In January 2026, Ziihera obtained conditional approval in Canada for the treatment of adults with previously treated, unresectable locally advanced or metastatic HER2-positive (IHC3+) BTC, as monotherapy.

In 2025, net product sales of Ziihera were $24.8 million, which represented less than 1% of our total net product sales for the year.

Modeyso. We completed the Chimerix Acquisition in April 2025 for a total of cash consideration of $944.2 million, adding Modeyso (dordaviprone), a protease activator of the mitochondrial ClpP that also inhibits DRD2, to our rare oncology portfolio. In August 2025, Modeyso was granted accelerated approval by FDA for the treatment of adult and pediatric patients 1 year of age and older with diffuse midline glioma harboring an H3 K27M mutation with progressive disease following prior therapy. Modeyso is the first and only treatment option approved by FDA for this ultra-rare and aggressive brain tumor that mainly affects children and young adults. Continued approval for this indication may be contingent upon verification and description of clinical benefit in the Phase 3 ACTION confirmatory trial. In connection with the approval by FDA of Modeyso in August 2025, we received a rare pediatric disease PRV, which we sold in January 2026 for total cash consideration of $200.0 million of which 50% is attributable to us.

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Net product sales of Modeyso in 2025 were$48.0 million, which represented 1%of our total net product sales for the year.

Zepzelca. We acquired U.S. development and commercialization rights to Zepzelca in early 2020, and launched six months thereafter, with an indication for treatment of patients with metastatic SCLC with disease progression on or after platinum-based chemotherapy. Zepzelca is an alkylating drug that binds guanine residues within DNA. This triggers a cascade of events that can affect the activity of DNA binding proteins, including some transcription factors, and DNA repair pathways, resulting in disruption of the cell cycle and eventual cell death. Our education and promotional efforts are focused on SCLC-treating physicians. We are continuing to market Zepzelca across academic and community cancer centers.

Our exclusive U.S. development and commercialization rights to Zepzelca were acquired through an exclusive license agreement we entered into with PharmaMar in December 2019. In October 2020, we entered into an amendment to the license agreement with PharmaMar to expand our exclusive license to include rights to develop and commercialize Zepzelca in Canada. The term of the amended license agreement extends on a licensed product-by-licensed product and country-by-country basis until the latest of: (i) expiration of the last PharmaMar patent covering Zepzelca in that country (subject to certain exclusions), (ii) expiration of regulatory exclusivity for Zepzelca in that country and (iii) 12 years after the first commercial sale of Zepzelca in that country. We have the right to terminate the amended license agreement at will upon a specified notice period, and either party can terminate the amended license agreement for the other party’s uncured material breach or bankruptcy.

Zepzelca was granted orphan drug designation for adults with metastatic SCLC with disease progression on or after platinum-based chemotherapy by FDA in August 2018. In December 2019, PharmaMar submitted an NDA to FDA for accelerated approval of Zepzelca for relapsed SCLC based on data from a Phase 2 trial, and in February 2020, FDA accepted the NDA for filing with priority review. In June 2020, FDA granted accelerated approval of Zepzelca for the treatment of adult patients with metastatic SCLC with disease progression on or after platinum-based chemotherapy. Zepzelca is approved based on response rate and duration of response. In October 2024, we announced positive top-line results from the Phase 3 IMforte trial showing a statistically significant and clinically meaningful progression-free survival and overall survival benefit for Zepzelca and atezolizumab in combination in the first-line maintenance setting. In June 2025, the sNDA submission for the combination of Zepzelca with atezolizumab or atezolizumab and hyaluronidase-tqjs was granted priority review by FDA and subsequently approved in October 2025 as a first-line maintenance treatment for adults with extensive-stage SCLC whose disease has not progressed after first-line induction therapy with atezolizumab, or atezolizumab and hyaluronidase-tqjs carboplatin and etoposide. In addition, our licensor PharmaMar is conducting a confirmatory trial in second-line SCLC. This is a three-arm trial comparing Zepzelca as either monotherapy or in combination with irinotecan to investigator’s choice of irinotecan or topotecan.

In 2025, net product sales of Zepzelca were $307.3 million, which represented 8% of our total net product sales for the year.

Rylaze. Rylaze was approved by FDA in June 2021 under the RTOR program, and was launched in the U.S. in July 2021, for use as a component of a multi-agent chemotherapeutic regimen for the treatment of patients with ALL, and LBL, in pediatric and adult patients one month and older who have developed hypersensitivity to E. coli-derived asparaginase. Rylaze is the only recombinant erwinia asparaginase manufactured product that maintains a clinically meaningful level of serum asparaginase activity throughout the entire intended course of treatment. We developed Rylaze to address the needs of patients and health care providers for an innovative, high-quality erwinia asparaginase with reliable supply.

The initial approved recommended dosage of Rylaze was for an IM administration of 25 mg/m2 every 48 hours. In November 2022, FDA approved an sBLA, for a Monday/Wednesday/Friday 25/25/50 mg/m2 IM dosing schedule. In September 2023, the EC granted marketing authorization for JZP458 (Rylaze) under the trade name Enrylaze®. Enrylaze was approved in Great Britain in January 2024, and is also approved in Canada, Switzerland and Australia.

In 2025, net product sales of Rylaze were $402.9 million, which represented 10% of our total net product sales for the year.

Revenue Diversification

As part of our objective to build a durable, growing commercial portfolio and reduce business risk by diversifying our revenue sources, we have been actively seeking to expand our commercial portfolio through a combination of launching internally developed therapies and commercial assets or investigational therapies acquired through corporate development. In 2020, 74% of total revenue was generated by one product, the high-sodium oxybate Xyrem. For the year ended December 31, 2025, 8% of total revenue was generated by Xyrem plus high-sodium oxybate AG royalty revenue.

Our lead marketed products, listed below, are approved in countries around the world to improve patient care.

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Product Indications Initial Approval Date Markets

Treatment of IH in adults. August 2021 U.S.

Treatment of cataplexy in patients with narcolepsy. May 2023 Canada

1 The clobazam restriction limited to EU and Great Britain

2 Accelerated approval received from FDA

3Conditional marketing authorization granted by EC

4 Conditional approval received from Health Canada

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Research and Development Progress

Our R&D activities encompass all stages of development and currently include clinical testing of new product candidates and activities related to clinical improvements of, or additional indications or new clinical data for, our existing marketed products. We also have active preclinical and early-stage programs for novel therapies that further our rare disease strategy and leverage the strong R&D capabilities we have built. We are increasingly leveraging our internal R&D function, and we have entered into collaborations with third parties for the R&D of innovative early-stage product candidates and have supported additional investigator-sponsored trials that are anticipated to generate additional data related to our products. We also seek out investment opportunities in support of the development of early- and mid-stage technologies in areas where we have deep expertise with a focus on validated targets and mechanisms. We have a number of licensing and collaboration agreements with third parties, including biotechnology companies, academic institutions and research-based companies and institutions, related to preclinical and clinical R&D activities.

Zanidatamab. Zanidatamab is a HER2-targeted bispecific antibody that can simultaneously bind two non-overlapping epitopes of HER2, known as biparatopic binding. Following positive data from a pivotal Phase 2 clinical trial evaluating zanidatamab monotherapy in patients with previously treated advanced or metastatic HER2-amplified BTC, we completed a BLA submission in second-line BTC in March 2024. In May 2024, FDA granted priority review of the BLA; we received FDA accelerated approval for this BLA in November 2024. In April 2025, we announced that CHMP adopted a positive opinion recommending the conditional marketing authorization of zanidatamab in second-line BTC. In June 2025, the EC granted conditional marketing authorization for Ziihera for the treatment of adults with unresectable locally advanced or metastatic HER2-positive (IHC3+) BTC previously treated with at least one prior line of systemic therapy.

In November 2025, we announced positive top-line results from the pivotal Phase 3 HERIZON-GEA-01 trial of zanidatamab in combination with chemotherapy, with or without tislelizumab, as first-line treatment for adults with HER2-positive locally advanced or metastatic GEA. In January 2026, we presented late-breaking results from the trial at ASCO GI. The investigational arm containing zanidatamab plus tislelizumab and chemotherapy demonstrated a statistically significant and clinically meaningful overall survival benefit of more than two years of median overall survival. The greater than seven-month improvement in median overall survival represents a 28% reduction in the risk of death versus the control arm. Both investigational arms led to a statistically significant and clinically meaningful median progression-free survival of more than one year, representing a greater than four-month improvement and 35% reduction in the risk of disease progression or death versus the control arm. FDA granted BTD for zanidatamab's development for patients with HER2+ unresectable locally advanced or metastatic GEA.

Zanidatamab is currently being evaluated in multiple clinical trials as a treatment for patients with HER2-expressing cancers: a Phase 2 DiscovHER-Pan-206 trial evaluating zanidatamab monotherapy in previously-treated patients with various HER2-positive (IHC3+) cancers, a Phase 2 EmpowHER-BC-208 trial to evaluate zanidatamab in patients with HER2-positive neoadjuvant and adjuvant breast cancer, a Phase 3 trial EmpowHER-303 to evaluate zanidatamab plus chemotherapy or trastuzumab plus chemotherapy in patients with HER2-positive breast cancer whose disease has progressed on previous T-DXd treatment, and a Phase 3 confirmatory trial examining zanidatamab in first-line patients with HER2-positive BTC.

Zepzelca. Our development plan for Zepzelca continues to progress. In October 2024, we announced positive top-line results from the Phase 3 IMforte trial showing a statistically significant and clinically meaningful benefit for Zepzelca and atezolizumab in combination in the first-line maintenance setting. In April 2025, we announced the submission of an sNDA to support this combination in the first-line maintenance setting. In June 2025, FDA granted priority review of the sNDA and we subsequently received FDA approval in October 2025 for the combination as a first-line maintenance treatment of adult patients with extensive-stage SCLC whose disease has not progressed after first-line induction therapy with atezolizumab or atezolizumab and hyaluronidase-tqjs, carboplatin and etoposide. In addition, our licensor PharmaMar is conducting a confirmatory trial in second-line SCLC. This ongoing three-arm trial is comparing Zepzelca as either monotherapy or in combination with irinotecan to investigator's choice of irinotecan or topotecan.

Updated results from the Phase 4 observational trial were presented at the 2025 WCLC that showed Zepzelca demonstrated clinically meaningful effectiveness across subgroups, including those with platinum-resistant disease and those with CNS metastases. The safety and tolerability profile observed in this Phase 4 study was consistent with prior findings, with no new safety signals reported.

JZP815. JZP815 is a pan-RAF kinase inhibitor that targets specific components of the MAPK pathway that, when activated by oncogenic mutations, can be a frequent driver of human cancer. In October 2022, we enrolled our first patient in a Phase 1 study to investigate the safety, dosing, and initial antitumor activity of JZP815 in participants with advanced or metastatic solid tumors harboring alterations in the MAPK pathway.

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JZP898. JZP898 is a differentiated, conditionally-activated IFNα INDUKINETM molecule. We acquired rights to JZP898 from Werewolf in 2022 under an exclusive, worldwide, royalty-bearing license to develop, manufacture and commercialize Werewolf's investigational WTX-613, now referred to as JZP898. In November 2023, we enrolled our first patient in a Phase 1 study to investigate the safety, tolerability, pharmacokinetics, immunogenicity and preliminary antitumor activity of JZP898 both as a monotherapy and in combination with pembrolizumab in adults with advanced/metastatic solid tumors.

Epidiolex. We have an ongoing Phase 1b study of Epidiolex for the treatment of focal-onset seizures. The study will assess the efficacy of Epidiolex as an adjunctive treatment in reducing the frequency of focal seizures compared to baseline as well as the effect of Epidiolex on health outcome endpoints in early line and refractory participants with focal-onset seizures.

Preclinical

Through third parties, we are also pursuing preclinical and clinical R&D activities under a number of licensing and collaboration agreements, including with:

•XLp for rights to use XLp’s PASylation® technology to extend the plasma half-life of selected asparaginase product candidates;

•Redx for preclinical collaboration activities related to G12D selective and pan-KRAS molecules that we purchased from Redx;

•Autifony to collaborate on discovering and developing drug candidates targeting two different ion channel targets associated with neurological disorders;

•Saniona to develop a small molecule activator of Kv7.2/Kv7.3 potassium channels for epilepsy and other potential indications; and

•We are also evaluating the use of our CombiPlex platform in a number of therapeutic formulations and combinations in oncology as part of our internal oncology R&D activities.

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Below is a summary of our key ongoing and planned development projects related to our products and pipeline and their corresponding current stages of development:

Product Candidates Description

Phase 3

Zanidatamab First-line HER2-positive GEA (HERIZON-GEA-01) (ongoing trial)

First-line HER2-positive BTC (HERIZON-BTC-302) (ongoing confirmatory trial)

Phase 2

Neoadjuvant and adjuvant breast cancer (EmpowHER-BC-208) (ongoing trial)

Phase 1

JZP815 Raf and Ras mutant tumors (acquired from Redx) (ongoing trial)

Epidiolex Focal-onset seizures

JZP047 Absence epilepsy

Preclinical

Undisclosed targets Oncology

CombiPlex® Hematology/oncology exploratory activities

Undisclosed targets SleepEpilepsyOther Neuroscience

1Also known as ONC206

2Also known as ONC212

3Also known as SAN2355

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Commercialization Activities

We have direct Jazz commercial operations in the U.S., Europe, Australia and Canada and a network of commercial distributors that represent our commercial interests in other key markets across the globe. In the U.S., our products are commercialized through a number of teams, including a team of experienced, trained sales professionals who provide education and promote Xywav, Epidiolex, Ziihera, Modeyso, Zepzelca, Rylaze, Vyxeos and Defitelio to healthcare providers in the appropriate specialties for each product. In addition, we have a team that interacts with payors and institutions to ensure access and coverage for the products, and a team that distributes the products throughout the U.S. healthcare system (wholesalers, pharmacies, hospitals, and community and academic institutions) and provides patient services.

In Canada and in approved markets in Europe and Australia where we commercialize Defitelio and Vyxeos, we have a field force of hematology sales specialists. In markets where these products either are not approved or are unable to be promoted under local regulation, we have medical affairs personnel responsible for responding to medical information requests and for providing information consistent with local treatment protocols with respect to such products. In certain European markets, Canada and Australia, we have a sales team and a team of medical science liaisons supporting our commercialization of Epidiolex/Epidyolex. In addition, we directly market Xywav, Zepzelca and Rylaze in Canada.

Other commercial activities include marketing related services, pricing and access, industry analytics and insights, distribution services and commercial support services. We employ third party vendors, such as advertising agencies, market research firms and suppliers of marketing and other sales support-related services, to assist with our commercial activities. We also provide reimbursement and patient assistance support for our U.S. markets.

We intend to scale the size of our sales force as appropriate to effectively reach our target audience in the specialty markets in which we currently operate. We promote Ziihera, Modeyso, Zepzelca, Rylaze, Vyxeos and Defitelio to many hematology and oncology specialists who operate in the same hospitals and outpatient clinical sites, and we believe that we benefit from operational synergies from this overlap. Continued growth of our current marketed products and the launch of any future products may require a reevaluation of our field force and support organization in and outside the U.S.

High Performance Organization and Human Capital Management

We are committed to creating a high performing organization grounded in purpose, defined by disciplined execution, and united by our mission to innovate to transform the lives of patients. Our goals are clear: (1) create a purpose-driven, people-centric, and exceptional place to work, and (2) live our core values of Integrity, Collaboration, Passion, Innovation, and Pursuit of Excellence in everything we do.

Employee Demographics. As of December 31, 2025, Jazz employed approximately 2,890 people worldwide, with approximately 53% in the U.S. and approximately 47% outside the U.S., primarily in the U.K., Ireland and across the EU. More than 740 employees – approximately 26% of our workforce – support our R&D activities, reflecting our continued investment in scientific excellence and innovation. We consider our employee relations to be good.

Company Culture. Our culture is rooted in purpose to make an impact on patients’ lives, shaped by deep scientific expertise and defined by disciplined execution. We bring a rare-disease mindset to our work – moving with urgency, clarity, and accountability. By fostering a people-centric and performance driven environment, we aim to create a workplace where purpose fuels passion and accountability drives results. At Jazz, our people and culture are central to driving innovation, performance, and long-term growth – we aim to foster a workplace where employees feel supported, connected, and empowered to deliver their best work.

We strive to create an environment where employees live our values, bring bold ideas forward, and operate with clarity and focus. We are committed to fostering an inclusive culture where all employees feel they belong – a culture that reflects the diverse perspectives of the patients and communities we serve and strengthens our ability to innovate and compete. Our belonging and inclusion strategy focuses on: (1) cultivating a workforce that reflects unique backgrounds, experiences, and talents (2) investing in and ensuring equal opportunities for our talent to develop; and (3) building a culture where inclusion and belonging are core to how we work.

We believe in a workforce and culture that fosters belonging and inclusion, and strengthens innovation, engagement, and performance. Our employee resource groups are open to all employees and include three ConcERTos, and six Affinity Forums. They provide platform engagement, education and community involvement. As of the end of 2025, 38% of our global workforce participated in at least one of these groups.

While we are proud of our progress, we remain committed to building an inclusive, high-performing workplace that supports employees of all backgrounds, including within our broader leadership.

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Employee Engagement. We have a strong employee value proposition anchored in our shared commitment to our purpose to innovate to transform the lives of patients and their families. We believe employee engagement and the power of employee voice is foundational to belonging and strong performance. Our teams are motivated by the opportunity to deliver meaningful impact for patients and are supported by a culture that values clarity, accountability, and scientific rigor. We maintain transparent and regular communication channels – including all-employee meetings, leadership messages, town halls, top leadership forums, pulse checks, and employee feedback surveys.

Our surveys consistently achieve participation rates above 75% and reflect strong engagement, including connection to purpose, sense of belonging, and confidence in Jazz as a great place to work. We continue to strengthen high-performance practices such as decision-making discipline, planning and prioritizing work, constructive challenge, accountability, and a growth mindset. Survey insights inform programs and activities that support our strategic priorities and our goal of building an agile, scalable operating culture.

Community Beat ConcERTo plays a key role in strengthening culture and belonging through local engagement activities that connect employees to our strategy, support communities, and promote well-being. They help foster connection across our hybrid working model by engaging remote employees and maximizing meaningful time together at our sites and offices.

Capabilities and Talent – Growth, Development and Total Rewards. As we enter our next chapter, we are strengthening the capabilities and culture that support our long-term growth ambition – expanding our rare-disease portfolio, executing with discipline, and building durable franchises that deliver meaningful value for patients and shareholders. We invest in the specialized scientific, clinical, and commercial capabilities that differentiate Jazz in rare disease and strengthen our right to win. Our talent strategy focuses on building and sustaining the capabilities required to advance our rare disease portfolio and deliver a disciplined approach to drive innovation.

We believe our people are the foundation of our future. Their expertise, resilience, and commitment to patients enable us to advance our strategy with focus and confidence. We aim to attract exceptional talent, recognize and reward high performance, and continually develop our people through meaningful experiences and learning opportunities. We maintain a strong focus on capability development and succession planning for critical roles. We regularly review talent development and succession plans across functions to support business continuity and develop a strong pipeline of future leaders.

We encourage our employees to engage in regular dialogue with their leaders to create development plans aligned to their aspirations and business needs. Our performance management process reinforces continual feedback, coaching, and growth through new experiences and learning. We encourage all employees to maintain an individual development plan outlining learning interests and focus areas.

We continue to sharpen the capabilities that fuel our performance – investing in capability development in key areas such as patient insights and evidence generation, clinical development excellence, AI-enabled tools, and customer experience platforms that support long-term success. Broadly across the organization, we leverage digital learning platforms to provide on demand learning across leadership, personal effectiveness, and well-being. We also offer self-service learning resources on topics such as high-performance teamwork, decision-making, hybrid working, and digital skills. Tuition reimbursement is available in our major markets to support career development.

We have strengthened our operating discipline through clearer enterprise priorities, aligned quarterly expectations, and cross functional ways of working that support consistent high-quality execution. In 2025, we continued to focus on the capabilities of our Global Leadership Team (Top 80 leaders) to strengthen leadership excellence and cross functional collaboration in pursuit of our enterprise strategic goals. We focused on a broader leadership group of people managers in 2025 to strengthen leadership behaviors linked to a high-performance culture, including constructive challenge, accountability, and enterprise-wide alignment to our goals.

We provide our employees with competitive and locally relevant compensation and benefits that support our overarching strategy to attract, retain and reward highly talented employees. This includes (1) broad-based participation in our annual incentive plan, which rewards employees based on the company’s achievement of pre-established goals (or sales targets in the case of sales incentive plans) as well as performance against their personal objectives (2) participation in our long-term equity incentive plans, which fosters an ownership culture and (3) benefits that support employee well-being.

We are committed to building and maintaining a culture of health and wellbeing. We support employees and their families through programs that inspire them to focus mental and emotional health, physical well-being, financial wellness, and work/life balance.

•We provide a robust set of offerings centered on mental and emotional health, including resilience, stress management, mindfulness and managing clinical conditions.

•We offer programs that promote activity, healthy nutrition habits, chronic condition prevention and early detection of more serious disease/illness.

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•We offer an enhanced suite of global paid leave and other time-off policies to address the differing needs of our employee population through varying stages of life, including minimum standards for new parent leave (irrespective of gender or how a family is created), family caregiver leave and bereavement leave. We offer a global volunteer day to provide employees time off with full pay to give back to their communities.

•Our Wellbeing Reimbursement Account reimburses employees for a wide array of expenses that support their overall wellbeing, empowering them to choose what is most important to them.

•In 2026, we will hold our second-ever Jazz Wellbeing Week, providing dedicated time off for self-care.

Employee Care. We are committed to providing a workplace where people feel invested in, valued and cared for, and a sense of belonging. We strive to enable our employees to live our values and support one another while delivering on our patient mission. Leader expectations and tools are essential as employee needs evolve – including flexibility, whole-person support, and productive work environments.

We provide productivity and collaboration tools and resources for remote work, training and tools for leaders managing distributed teams, flexibility within work schedules and leave programs, expanded employees assistance and mindfulness programs, and increased investment in resources focused on inclusion and belonging.

Through direct input from employees, external insights and best practices, we developed our flexible working model; expanding the power of intentional collaboration and our ability to more effectively manage our global and highly distributed team workforce. This approach to work, called “Jazz Remix,” aims to provide eligible employees with the greatest flexibility and agility to globally connect, collaborate, innovate and perform.

Environment, Health and Safety. Our operations are subject to complex and increasingly stringent environmental, health and safety laws and regulations in the countries where we operate and, in particular, in Ireland, the U.K. and Italy where we have manufacturing facilities. Our manufacturing activities involve the controlled storage, use and disposal of chemicals and solvents. Environmental and health and safety authorities administer laws governing, among other matters, the emission and discharge of pollutants, hazardous substances, workplace exposure, and employee and public welfare. In certain cases, such laws, directives and regulations may impose strict liability for pollution of the environment and contamination resulting from spills, disposals or other releases of hazardous substances or waste. Costs, damages and/or fines may result from the presence, investigation and remediation of such contamination at properties currently or formerly owned, leased or operated by us or at off-site locations, including where we have arranged for the disposal of hazardous substances or waste. In addition, we may be subject to third party claims, including for natural resource damages, personal injury and property damage, in connection with such contamination.

We seek to operate our manufacturing facilities in an environmentally responsible way to protect our people, our business, our environment and the local communities in which we operate. We have adopted internal environmental policies and management systems designed to support compliance with applicable laws, directives and regulations on environmental protection and in support of environmental sustainability and local biodiversity. These include procedures for assessing compliance with applicable environmental laws and regulations and reporting incidents of non-compliance to applicable governmental authorities. For example, we have environmental policies governing our manufacturing facilities in Ireland, the U.K. and Italy, which demonstrate our commitment to environmental sustainability and require us to minimize resource use (e.g., energy and water) and waste generation, optimize the use of raw materials, and undertake continuous improvement in environmental performance, with an emphasis on pollution prevention.

Competition

The biopharmaceutical industry is highly competitive. Our products compete, and our product candidates may in the future compete, with currently existing therapies, product candidates currently under development by us and others and/or future product candidates, including new chemical entities that may be safer, more effective or more convenient than our products. Any products that we develop may be commercialized in competitive markets, and our competitors, which include large global pharmaceutical companies and small research-based companies and institutions, may succeed in developing products that render our products obsolete or noncompetitive.

With respect to competition we face from generic drugs, certain U.S. state laws allow for, and in some instances in the absence of specific instructions from the prescribing physician mandate, the dispensing of generic products rather than branded products when a generic version is available. Generic competition often results in decreases in the net prices at which branded products can be sold.

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In particular, our products and most advanced product candidates face or may face competition as described below:

•Xywav and Xyrem. Xywav and Xyrem are approved by FDA and marketed in the U.S. for the treatment of both cataplexy and EDS in both adult and pediatric patients with narcolepsy. We and others have launched products to treat EDS in narcolepsy and may in the future launch additional products to treat cataplexy in narcolepsy that are competitive with or disrupt the market. Xywav and Xyrem face competition from Alkermes’ Lumryz (acquired through its acquisition of Avadel), a branded product for treatment of cataplexy and/or EDS in narcolepsy. Lumryz, a once-nightly dose, high-sodium oxybate, was launched in the U.S. market in June 2023, as well as potential future competition from generic versions of high-sodium oxybate, including a generic version of high-sodium oxybate from Amneal approved in September 2025 and from Ascent approved in November 2025. We and Avadel were engaged in various litigation regarding Lumryz and our oxybate products, which was settled in September 2025. For additional information on litigation and the related settlement involving this matter, see “FDA Litigation” and “Avadel Litigation” in Note 13, Commitments and Contingencies-Legal Proceedings of the Notes to Consolidated Financial Statements, included in Part IV of this Annual Report on Form 10‐K.

In addition, since January 2023, our oxybate products have faced competition from AG high-sodium oxybate pursuant to a settlement agreement we entered into with an ANDA filer, and from July 2023 through the end of 2025, an additional AG version of high-sodium oxybate from a volume-limited ANDA filer. Collectively, these AG versions of high-sodium oxybate have negatively impacted and are expected to continue to negatively impact Xyrem and Xywav sales for patients with narcolepsy. Specifically, a wholly owned subsidiary of Hikma launched its AG version of high-sodium oxybate in January 2023. In September, 2023, Hikma had elected to continue to sell the Hikma AG product, with royalties to be paid to us, for an additional four years beginning in January 2024. Pursuant to amendments to our AG agreement with Hikma, effective January 1, 2026, we extended the period during which Hikma is permitted to sell the Hikma AG product until December 31, 2029. Either we or Hikma may provide notice of intent to terminate the amended agreement as early as October 1, 2026, in accordance with notice provisions in the agreement. Under these amendments, we continue to have the right to a meaningful royalty from Hikma on net sales of the Hikma AG product throughout the extended Hikma AG period, which royalty rate was fixed through the end of 2025 and then subject to specified reductions as set forth in our agreement with Hikma. We are also paid for supply of the Hikma AG product and are reimbursed by Hikma for a portion of the services costs associated with the operation of the Xywav and Xyrem REMS, and distribution of the Hikma AG product. Hikma also maintains a license to launch its own generic sodium oxybate product, but, if it elects to launch its own generic product, Hikma will no longer have the right to sell the Hikma AG product. In addition, Hikma would need to set up its own REMS (or join an existing REMS operated by another company), which must be open to any other company seeking to commercialize a sodium oxybate product. Amneal also had rights to sell a low-single-digit percentage of historical Xyrem sales over each 6-month sales period, which terminated at the end of 2025. In September 2025, Amneal received FDA approval for a generic version of high-sodium oxybate. In addition, in November 2025, Ascent received FDA approval for a generic version of high-sodium oxybate. For a description of generic versions of sodium oxybate and/or new products for the treatment of cataplexy and/or EDS that currently compete or could in the future compete with, or otherwise disrupt the market for, Xywav and Xyrem, as well as a description of our settlement agreements with ANDA filers, see the risk factor under the heading “The introduction of new products in the U.S. market that compete with, or otherwise disrupt the market for, our oxybate products has adversely affected and may continue to adversely affect sales of our oxybate products” in Part I, Item 1A of this Annual Report on Form 10‐K.

In addition, Xywav and Xyrem may face competition in the future from other new sodium oxybate formulations for treatment of narcolepsy. Also, in the future we expect competition from generic versions of sodium oxybate. For example, we received notices in June 2021, February 2023 and July 2025, that Lupin, Teva and Granules, respectively, filed ANDAs for generic versions of Xywav. Furthermore, in January 2026, we received notices from Tris Pharma that it had filed with FDA a Section 505(b)(2) NDA for generic versions of Xyrem and Xywav. On October 13, 2023, Lupin announced that it has received tentative approval for its application to market a generic version of Xywav.

Non-oxybate products intended for the treatment of EDS or cataplexy in narcolepsy or IH (Xywav is the first and only FDA-approved therapy to treat IH), including new market entrants, even if not directly competitive with Xywav or Xyrem, could have the effect of changing treatment regimens and payor or formulary coverage of Xywav or Xyrem in favor of other products, and indirectly materially and adversely affect sales of Xywav and Xyrem. Xywav and Xyrem face competition from Sunosi, which we sold to Axsome in 2022. Xywav and Xyrem may face increased competition from new branded entrants to treat EDS or cataplexy in narcolepsy such as pitolisant, which has been approved by FDA for the treatment of both cataplexy and EDS in adult patients with narcolepsy. Harmony Biosciences has announced a phase 3 study for pitolisant for IH after receiving a refusal to file from FDA in February 2025. In addition, Alkermes acquired Avadel in February 2026, which may strengthen both companies and

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we may experience increased competition from the combined company. Other companies have announced that they have product candidates in various phases of development to treat the symptoms of narcolepsy, such as Axsome’s reboxetine, and various companies are performing R&D on orexin 2 receptor agonists for the treatment of sleep disorders, including narcolepsy and IH, which companies include Takeda, Merck & Co., Inc., Eisai Co., Ltd., Centessa Pharmaceuticals plc and Alkermes.

In addition, we are also aware that prescribers often prescribe branded or generic medications for cataplexy and IH before prescribing or instead of prescribing oxybate therapy, and that payors often require patients to try such medications before they will cover Xywav or Xyrem, even if they are not approved for this use. For example, prescribers often treat mild cataplexy with drugs that have not been approved by FDA for this indication, including tricyclic antidepressants and selective serotonin reuptake inhibitors or selective norepinephrine reuptake inhibitors. We are also aware that branded or generic stimulants may be prescribed off-label for treatment of EDS in narcolepsy. Wake-promoting agents modafinil and armodafinil, including both branded and generic equivalents, are approved for the treatment of EDS in narcolepsy and other conditions, and may be used in conjunction with or instead of Xywav or Xyrem.

•Epidiolex. Patients in the U.S. suffering from seizures associated with DS, LGS or TSC are treated with a variety of FDA-approved products, including clobazam, clonazepam, valproate, lamotrigine, levetiracetam, rufinamide, topiramate, ethosuximide, and zonisamide. FDA approved Zogenix, Inc.'s low-dose fenfluramine in DS in June 2020, and for LGS in March 2022. In March 2022, UCB S.A. announced that it had completed its acquisition of Zogenix. FDA approved Marinus Pharmaceuticals, Inc.’s ganaxolone for the treatment of seizures associated with cyclin-dependent kinase-like 5 deficiency disorder in March 2022. Ovid Therapeutics Inc./Takeda, Eisai Company Limited, Praxis Precision Medicines, Inc., Bright Minds Biosciences Inc., H Lundbeck A/S and others are developing therapies for treating Developmental and Epileptic Encephalopathies (includes DS and LGS). Stiripentol has been approved in Europe for several years to treat DS and was approved in 2018 by FDA. There are a number of public and private companies in various stages of developing genetic therapies for DS, including Stoke Therapeutics, Inc., which has an antisense oligonucleotide, STK-001, in clinical trials.

In addition, there are non-FDA approved CBD preparations being made available from companies in the medical marijuana industry, which might attempt to compete with Epidiolex. While federal law prohibits the sale and distribution of most marijuana products not approved or authorized by FDA, the vast majority of states and the District of Columbia have legalized either CBD or marijuana for either recreational or medical use, or both. Under the U.S. Farm Bill, enacted in late 2018, certain extracts and other material derived from cannabis are no longer controlled under the CSA. However, the marketing of such products as a food, dietary supplement, or for medical purposes remains subject to FDA requirements. With respect to the marketing of CBD as a food or dietary supplement, in January 2023, FDA concluded that the existing regulatory frameworks for foods and supplements were not appropriate for CBD products and denied three citizen petitions that had asked the agency to conduct rulemaking to allow the marketing of CBD products as dietary supplements. In addition, U.S. Congressional efforts related to legalization of marijuana continue. Although our business is distinct from that of entities marketing FDA-unapproved marijuana and CBD-containing dietary supplements, future legislation or federal government action authorizing the sale, distribution, use, and insurance reimbursement of non-FDA approved marijuana or CBD products could increase competition for and adversely affect our ability to generate sales of Epidiolex and our cannabinoid product candidates.

We are aware of exploratory research into the effects of tetrahydrocannabinol, often referred to as THC, and CBD drug formulations; discovery research within the pharmaceutical industry into synthetic agonists and antagonists of CB1 and CB2 receptors; companies that supply synthetic cannabinoids and cannabis extracts to researchers for pre-clinical and clinical investigation; and various companies that cultivate cannabis plants with a view to supplying herbal cannabis or nonpharmaceutical cannabis-based formulations to patients. These activities have not been approved by FDA but may in the future compete with our products.

Moreover, we expect that Epidiolex will face competition from generic products in the future. In November and December 2022, we received notices from various ANDA filers that they have each filed with FDA an ANDA for a generic version of Epidiolex (cannabidiol) oral solution. In January 2023, we filed patent infringement suits against these ANDA filers. From October 2023 through January 2025, we entered into settlement agreements with each of the Epidiolex ANDA Filers that resolved our patent litigation with them related to Epidiolex. Under the settlement agreements, we granted each of the Epidiolex ANDA Filers a license to manufacture, market, and sell its own generic version of Epidiolex beginning in the very late 2030s, or earlier under certain circumstances, including but not limited to the launch of another generic Epidiolex product or a final decision that all unexpired claims of the Epidiolex patents are not infringed, or are invalid and/or unenforceable.

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•Zepzelca. Zepzelca faces competition from topotecan and tarlatamab, which are approved treatments in second line SCLC in the U.S., as well as other regimens for relapsed SCLC currently recommended in compendia guidelines, including rechallenge with first-line platinum chemotherapy. There are also a number of products for the treatment of first and second line SCLC in various phases of development, including Amgen Inc.’s tarlatamab, which was approved for second line use in the U.S. in May 2024. Moreover, we expect that Zepzelca will face competition from generic products in the future. In July and August 2024, we received notices from various ANDA filers that they have each filed with FDA an ANDA for a generic version of Zepzelca. In September 2024, we filed patent infringement suits against these ANDA filers. In September 2025, we filed an additional lawsuit against each of the Zepzelca ANDA Filers, alleging that, by filing its ANDA, each party infringed the newly-issued patent related to a method of treatment using Zepzelca. For a description of this litigation, see “Zepzelca Patent Litigation” in Note 13, Commitments and Contingencies-Legal Proceedings of the Notes to Consolidated Financial Statements, included in Part IV of this Annual Report on Form 10‐K. As a result of these lawsuits, we expect that a stay of approval of up to 30 months will be imposed by FDA on these ANDA filers.

•Rylaze. Rylaze may face competition from Erwinaze in the future. Erwinaze was previously approved and commercialized by us as a treatment for ALL patients with hypersensitivity to E. coli-derived asparaginase. In April 2020, PBL granted Clinigen a global license for Erwinaze. However, in December 2021, Clinigen announced that FDA issued a complete response letter to PBL’s BLA for Erwinaze, indicating that the BLA cannot be approved in its current form. Outside of the U.S., Enrylaze faces competition from Erwinase. Rylaze may also face competition from other companies who have developed or are developing new treatments for ALL. In addition, some new asparaginase treatments could reduce the rate of hypersensitivity in patients with ALL, and new treatment protocols are being developed and approved for ALL that may not include asparaginase-containing regimens, including some for the treatment of relapsed or refractory ALL patients.

•Vyxeos. With respect to Vyxeos, there are a number of alternative established therapies in AML. A key consideration in the treatment of AML patients is the patient’s suitability for chemotherapy. The AML patient population studied in the Vyxeos Phase 3 clinical trial supporting our NDA included 60-75 year old fit patients, or those deemed able to tolerate intensive induction chemotherapy. Prior to Vyxeos, the most widely recognized option for the treatment of newly-diagnosed t-AML and AML-MRC in fit patients was cytarabine in combination with daunorubicin, known as 7+3, which is still used today in this population, along with other intensive chemotherapy regimens, particularly in patients under the age of 60. Also, since Vyxeos was approved, several other products have been approved by FDA or are in development as treatment options for newly diagnosed AML patients eligible for intensive chemotherapy, such as targeted agents (e.g. midostaurin, enasidenib and ivosidenib), immunotherapies (e.g., gemtuzumab ozogamicin and chimeric antigen receptor T-cell therapy), and agents disrupting leukemia cell survival (e.g., glasdegib). We are also aware of the increasing use of venetoclax combined with either a hypomethylating agent or low-dose cytarabine, a treatment approved by FDA in newly diagnosed AML patients who are age 75 years or older, or who have comorbidities that preclude use of intensive induction chemotherapy. With ongoing trends in the U.S. towards lower-intensity treatments and away from intensive chemotherapy regimens for AML, we note increasing competition from other therapeutic options as we continue to educate providers on the clinical benefits of Vyxeos in appropriate patients.

•Defitelio. Defitelio is the first and only approved treatment for patients with VOD, sVOD, or VOD with renal or pulmonary dysfunction following HSCT by regulatory authorities in the U.S., Europe, Japan and other markets. Utilization of Defitelio is in part driven by evolving treatment practices in HSCT. While there is currently no direct competition to Defitelio to treat sVOD, changes in the types of conditioning regimens used as part of HSCT may affect the incidence of VOD diagnosis and demand for Defitelio. In December 2024, FDA accepted an ANDA for a generic version of Defitelio. In March 2025, we received a notice from Almaject that it had filed with FDA an ANDA for a generic version of Defitelio. In April 2025, we filed a patent infringement lawsuit against Almaject. For a description of this litigation, see “Defitelio Patent Litigation” in Note 13, Commitments and Contingencies-Legal Proceedings of the Notes to Consolidated Financial Statements, included in Part IV of this Annual Report on Form 10‐K. As a result of this lawsuit, we expect that a stay of approval of up to 30 months will be imposed by FDA on Almaject’s ANDA.

•Ziihera. Ziihera faces competition from generic chemotherapies, including cisplatin/gemcitabine rechallenge, and other HER2 directed therapies, including Enhertu and trastuzumab.

An important part of our corporate strategy is to build a diversified product pipeline, including by acquiring or in-licensing and developing, or partnering to license and develop, additional products and product candidates that we believe are highly differentiated and have significant commercial potential. Our ability to continue to grow our product portfolio requires that we compete successfully with other pharmaceutical companies, many of which may have substantially greater financial sales and marketing resources, to acquire or in-license products and product candidates.

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Customers

In the U.S., Xywav and Xyrem are sold to one certified specialty pharmacy, ESSDS, that ships Xywav and Xyrem directly to patients. Also in the U.S., Epidiolex is sold to specialty pharmacies and specialty distributors. Modeyso is sold to one certified specialty pharmacy, Onco360, that ships Modeyso directly to patients. Defitelio is sold to hospital customers through subsidiary specialty distributors of McKesson. Zepzelca, Rylaze, Ziihera and Vyxeos are sold to customers through subsidiary specialty distributors of McKesson, Cencora, and Cardinal. We have distribution services agreements made in the ordinary course of business with McKesson, Cencora and Cardinal and a pharmacy services agreement with ESSDS. For more information regarding our relationship with ESSDS, see “Business—Our Commercialized Products—Xywav and Xyrem REMS” in this Part I, Item 1. Purchases are made on a purchase order basis.

In certain countries in Europe, Defitelio and Vyxeos are sold pursuant to marketing authorizations. We distribute these products through Durbin PLC, a U.K.-based wholesaler and distributor, and O&M Movianto Nederland BV, our centralized European logistics services provider, to hospitals and local wholesalers in Europe where we market these products directly and, in other markets in Europe and elsewhere where we do not market these products directly, to local distributors and wholesalers. In certain countries in Europe, Epidyolex is sold pursuant to marketing authorizations. We distribute Epidyolex through a variety of wholesalers and distributors. In countries where there is no marketing authorization, Epidyolex is available pursuant to named patient programs, temporary use authorizations or similar authorizations in accordance with local regulations controlling the medical use of unapproved products.

We commercialize and distribute Xyrem in Canada for the treatment of cataplexy in adult patients with narcolepsy. Xyrem is also sold in certain countries outside the U.S. and Canada by UCB under the UCB license. In July 2024, the parties agreed to terminate the UCB license. UCB has up to two years from the execution of the termination agreement to withdraw the marketing authorization for Xyrem in all applicable territories.

Manufacturing

We have a manufacturing and development facility in Athlone, Ireland where we manufacture Xywav and Xyrem, a manufacturing and development facility in Kent Science Park, U.K. where we produce Epidiolex/Epidyolex, and a manufacturing plant in Villa Guardia, Italy where we produce defibrotide drug substance. We currently do not have our own commercial manufacturing or packaging capability for our other products, product candidates or their APIs. As a result, our ability to develop and supply products in a timely and competitive manner depends on third party suppliers being able to meet our ongoing commercial and clinical trial needs for API, other raw materials, packaging materials and finished products.

Marketed Products

Xywav and Xyrem. Xywav and Xyrem are manufactured by Patheon under the Patheon Agreement entered into with Patheon in 2015 and also by us in our Athlone facility. Most of our U.S. commercial supply is manufactured by Patheon. The current term of the Patheon Agreement will expire in December 2026, subject to further automatic two-yearly extensions if Patheon is then providing manufacturing services for any product, unless either party provides prior notice of termination. In addition, we may terminate the Patheon Agreement for any reason upon 12 months’ prior written notice.

Xywav, like Xyrem, is a Schedule III controlled substance in the U.S. The API of Xywav are the calcium, magnesium, potassium and sodium salts of GHB, which are Schedule I controlled substances in the U.S. As a result, Xywav and Xyrem are subject to regulation by the DEA under the CSA, and its manufacturing and distribution are highly restricted. Quotas from the DEA are required in order to manufacture or procure calcium, magnesium, potassium and sodium salts of GHB in the U.S. For information related to DEA quota requirements, see “Business—Government Regulation—Other Post-Approval Pharmaceutical Product Regulation—Controlled Substance Regulations” in this Part I, Item 1.

Siegfried supply sodium oxybate, the API of Xyrem, to Patheon and our Athlone facility. Although Siegfried has been our only supplier of sodium oxybate since 2012, we have the right to purchase a portion of our worldwide requirements of sodium oxybate from other suppliers. The agreement with Siegfried expires in April 2027, subject to automatic three-year extensions until either party provides advance notice of its intent to terminate the agreement. During the term of the agreement and, under certain circumstances for 18 months after the agreement terminates, Siegfried is not permitted to manufacture sodium oxybate for any other company.

Epidiolex. Epidiolex/Epidyolex is manufactured by us in our Kent Science Park facility in the U.K. Epidiolex is a pharmaceutical formulation comprising highly purified plant-derived CBD. We cultivate our cannabinoid plants in the U.K. under highly controlled and standardized conditions.

Ziihera. Ziihera is manufactured by WuXi (Hong Kong) at their manufacturing site in WuXi, PRC. The term of the agreement with WuXi (Hong Kong) will expire in March 2029 and will then be subject to automatic three year extensions, unless either party provides advance notice of its intent to terminate the agreement. We have the right to appoint an alternate

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contract manufacturer at our discretion. In January 2026, we entered into a development and services agreement with Lonza AG and Lonza Sales AG for the commercial supply of Ziihera in the U.S. beginning in 2029.

Modeyso. Modeyso is manufactured by Adare, which is a sole source supplier. We source the API of Modeyso from ChemSpec USA, LLC. Adare is the sole provider of our commercial and clinical supply of Modeyso; however, we are not required to purchase Modeyso exclusively from Adare. If Adare does not or is not able to supply us with Modeyso for any reason, it may take time and resources to implement and execute the necessary technology transfer to another processor, this could be executed with a relative low technical risk and minimal risk of delay, as such this is unlikely to negatively impact our anticipated revenues from Modeyso.

Zepzelca. Zepzelca is manufactured by Simtra. The current term of the agreement with Simtra will expire in December 2029 and will then be subject to automatic two-year extensions, unless either party provides advance notice of its intent to terminate the agreement. PharmaMar retains manufacturing rights for the API for U.S. and Canadian commercial supply of Zepzelca.

Rylaze. Rylaze is currently manufactured by Patheon, and the API of Rylaze is manufactured by AGC Biologics A/S. The initial term of the agreement with Patheon expired in December 2025 and allows for automatic two-year extensions, unless either party provides advance notice of its intent to terminate the agreement. Patheon informed us that they will terminate the manufacturing agreement effective end of 2026. The initial term of the agreement with AGC Biologics A/S will expire in October 2026 and will then be subject to automatic three-year extensions, unless either party provides advance notice of its intent to terminate the agreement.

Vyxeos. Vyxeos is manufactured by Simtra, which is a sole source supplier from a single site location, using our CombiPlex platform. CombiPlex products represent formulations with increased manufacturing complexities associated with producing drug delivery vehicles encapsulating two or more drugs that are maintained at a fixed ratio and, in the case of Vyxeos, two drugs that are co-encapsulated in a freeze-dried liposomal format. Our manufacturing agreement with Simtra expires in December 2029, subject to automatic three-year renewal terms, unless either party provides advance notice of its intent to terminate the agreement. While other contract manufacturers may be able to produce Vyxeos, the proprietary technology that supports the manufacture of Vyxeos is not easily transferable.

Defitelio. We are our own sole supplier of, and we believe that we are currently the sole worldwide producer of, defibrotide API. We manufacture defibrotide API from porcine DNA in a single facility located in Villa Guardia, Italy. Patheon currently processes defibrotide API into its finished vial form under a specific product agreement entered into under a separate agreement with Patheon. Patheon is the sole provider of our commercial and clinical supply of Defitelio; however, we are not required to purchase Defitelio exclusively from Patheon. If Patheon does not or is not able to supply us with Defitelio for any reason, it may take time and resources to implement and execute the necessary technology transfer to another processor, and such delay could negatively impact our anticipated revenues from Defitelio and could potentially cause us to breach contractual obligations with customers or to violate local laws requiring us to deliver the product to those in need.

Product Candidates

For discussion of the challenges we face with respect to supply of our products and product candidates, see the risk factor under the heading “Delays or problems in the supply of our products for sale or for use in clinical trials, loss of our single source suppliers or failure to comply with manufacturing regulations could materially and adversely affect our business, financial condition, results of operations and growth prospects” in Part I, Item 1A of this Annual Report on Form 10‐K.

Patents and Proprietary Rights

We actively seek to patent, or to acquire or obtain licenses to third party patents, to protect our products and product candidates and related inventions and improvements that we consider important to our business. We own a portfolio of U.S. and ex-U.S. patents and patent applications and have licensed rights to a number of issued patents and patent applications. Our owned and licensed patents and patent applications cover or relate to our products and product candidates, including certain formulations, used to treat particular conditions, distribution methods and methods of administration, drug delivery technologies and delivery profiles and methods of making and use. Patents extend for varying periods according to the date of the patent filing or grant and the legal term of patents in the various countries where patent protection is obtained. The patent laws of ex-U.S. countries differ from those in the U.S., and the degree of protection afforded by ex-U.S. patents may be different from the protection offered by U.S. patents. In addition to patents, our products and product candidates are in some instances protected by various regulatory exclusivities. For a description of those exclusivities and their regulatory background, see “Business—Government Regulation—Marketing Exclusivity—The Hatch-Waxman Act” in this Part I, Item 1.

The patents, patent applications and regulatory exclusivities that relate to our marketed products include:

•Xywav. We have 15 U.S. patents that relate to Xywav. These patents expire from 2033 to 2041. In addition, we have patent applications that relate to Xywav for use in additional indications that would, if issued, expire between

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2040 and 2041. Xywav has been granted ODE by FDA to treat narcolepsy through January 2028 (inclusive of six months of pediatric exclusivity) and to treat IH through August 2028. Some of our Xywav patents have been subject to patent litigation with the companies who filed ANDAs seeking to market a generic version of Xywav. For example, we received notices in June 2021, February 2023 and July 2025 that Lupin, Teva and Granules, respectively, filed ANDAs for generic versions of Xywav. In January 2026, we received notices from Tris Pharma that it had filed with FDA a Section 505(b)(2) NDA for generic versions of Xyrem and Xywav. For additional information on litigation involving these matters, see Note 13, Commitments and Contingencies-Legal Proceedings of the Notes to Consolidated Financial Statements, included in Part IV of this Annual Report on Form 10‐K.

•Xyrem. We currently have seven issued patents in the U.S. relating to Xyrem listed in the Orange Book. Our patents relate to a DDI between Xyrem and divalproex sodium. In October 2018, due to FDA’s grant of pediatric exclusivity, an additional six months was added to the original expiration dates of all of our Orange Book-listed patents that existed at that time. As a result, our Orange Book-listed patents have periods of exclusivity between March and September 2033. Although we have settled all patent litigation against the ten companies that filed ANDAs seeking to market a generic version of Xyrem, additional companies may challenge our U.S. patents for Xyrem in the future. For a description of our Xyrem settlements, see the risk factor under the heading “The introduction of new products in the U.S. market that compete with, or otherwise disrupt the market for, our oxybate products has adversely affected and may continue to adversely affect sales of our oxybate products” in Part I, Item 1A of this Annual Report on Form 10‐K.

The European Patent Office issued a method of administration patent relating to the DDI between Xyrem and divalproex sodium that expires in 2034.

•Epidiolex. Our patent portfolio relating to the use of CBD in the treatment of epileptic encephalopathies includes 32 issued U.S. patents listed in the Orange Book. These patents claim the use of CBD for the treatment of convulsive, drop and atonic seizures associated with both LGS and DS, an oral composition of CBD, as well as the use of CBD in combination with clobazam, and the teaching that dose adjustment may be needed when concomitantly prescribed. The patents currently listed in the Orange Book will expire between 2035 and 2041. We have filed corresponding patent applications in many jurisdictions worldwide, including Europe, U.K., Canada, Japan, Mexico, Australia and New Zealand. The USPTO has granted two patents based on data that demonstrates that Epidiolex provides a benefit over synthetic CBD in an animal model of epilepsy, which will expire in 2039 and which are listed in the Orange Book. Epidiolex has received ODE to treat seizures associated with LGS and DS, which expired in September 2025, and TSC, which expires in July 2027.

•Ziihera. In 2022, we obtained a license from Zymeworks BC Inc., which included rights to a portfolio of U.S. and ex-U.S. patents and patent applications, including compositions and methods of using Ziihera. The portfolio contains a U.S. composition of matter patent relating to Ziihera, which expires in 2034 (excluding any adjustments or extensions).

•Modeyso. As a result of the Chimerix Acquisition, we acquired a portfolio of U.S. and international patents and patent applications for Modeyso, which cover methods of use and pharmaceutical formulations. There are seven patents listed in the Orange Book, with the last patent set to expire on January 30, 2037. This expiration excludes an additional two years of patent term extension, for which the application is currently pending with the USPTO. Modeyso has also received orphan drug designation and new chemical entity status, which will expire on August 6, 2030. ODE for Modeyso is expected and, if granted, will expire on August 6, 2032.

•Zepzelca. In December 2019, we entered into an exclusive license agreement with PharmaMar pursuant to which we obtained exclusive U.S. development and commercialization rights to Zepzelca. In October 2020, we entered into the amended license agreement which expanded our exclusive license to include rights to develop and commercialize Zepzelca in Canada. We have a portfolio of in-licensed U.S. and Canadian patents for lurbinectedin relating to compositions, methods of use, and processes. For example, one Orange Book listed U.S. patent (expiring in 2029, with granted patent term extension) covers a genus of compounds, including lurbinectedin, and use in treating various cancers. A request for extension (CSP) has also been filed in Canada. Zepzelca has also been granted ODE for the treatment of adults with metastatic SCLC with disease progression on or after platinum-based chemotherapy until 2027 and new chemical entity exclusivity, which expired in 2025. In October 2025, we received approval for Zepzelca in a second indication, as a first-line maintenance treatment for adults with ES-SCLC in combination use of lurbinectedin with atezolizumab. ODE for the second indication is anticipated, which if granted, would expire in October 2032. In July and August 2024, we received notices from various ANDA filers that they have each filed with FDA an ANDA for a generic version of Zepzelca. In September 2024, we filed patent infringement suits against these ANDA filers. For a description of this litigation, see “Zepzelca Patent Litigation” in Note 13, Commitments and Contingencies-Legal Proceedings of the Notes to Consolidated Financial Statements, included in Part IV of this

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Annual Report on Form 10‐K. As a result of these lawsuits, we expect that a stay of approval of up to 30 months will be imposed by FDA on these ANDA filers.

•Rylaze. In 2016, we obtained worldwide rights from Pfenex, including Pfenex’s patent rights relating to Rylaze, to develop and commercialize multiple early-stage hematology product candidates, including a license to two U.S. process patents relating to Rylaze, with respective expirations in 2026 and 2038. Pfenex has been acquired by Ligand. Rylaze has been granted orphan drug designation for the treatment of patients with ALL or LBL. We have two patent application families relating to dosing regimens. One covers the dosing regimen (25mg/m2 intramuscularly every 48 hours), while the other covers various dosing regimens of interest. If issued, these would expire in 2040 and 2042, respectively. Another patent application relating to formulations of asparaginase would expire in 2042, if issued.

•Vyxeos. We have a portfolio of U.S. and ex-U.S. patents and patent applications for Vyxeos and the CombiPlex platform relating to various compositions and methods of making and use. These include six Orange Book listed U.S. patents covering Vyxeos compositions and methods of use expiring between 2026 and 2033 (including pediatric extensions) and two U.S. patents covering CombiPlex (which also cover Vyxeos) expiring in July 2027 (including pediatric extensions). In March 2021, FDA approved an expanded label for Vyxeos for the treatment of t-AML or AML-MRC in pediatric patients 1 year and older. In addition, Vyxeos was granted OME by the EC until August 2028, ten years from its EC approval for the treatment of adults with newly-diagnosed t-AML or AML-MRC. Vyxeos was approved by Health Canada for treatment of adults with newly diagnosed t-AML or AML-MRC in April 2021. Vyxeos was approved in March 2024 in Japan and designated as an orphan drug.

•Defitelio. The unique process of deriving defibrotide from porcine DNA is extensive and uses both chemical and biological processes that rely on complex characterization methods. We have U.S. and ex-U.S. patents and patent applications relating to various compositions, methods of use and methods of characterization, with the issued patents expiring at various times between 2021 and 2035. Three U.S. patents are listed in the Orange Book. In December 2024, FDA accepted an ANDA from Almaject for a generic version of Defitelio. We received notice by Almaject of this ANDA filing in March 2025. In April 2025, we filed a patent infringement lawsuit against Almaject. For a description of this litigation, see “Defitelio Patent Litigation” in Note 13, Commitments and Contingencies-Legal Proceedings of the Notes to Consolidated Financial Statements, included in Part IV of this Annual Report on Form 10‐K. As a result of this lawsuit, we expect that a stay of approval of up to 30 months will be imposed by FDA on Almaject’s ANDA. Defibrotide has also been granted orphan drug designation by the Korean Ministry of Food and Drug Safety to treat and prevent VOD, by the Commonwealth of Australia-Department of Health for the treatment of VOD and by the EC for the prevention of acute Graft-versus-Host Disease. We acquired the rights to defibrotide for the treatment and prevention of VOD in North America, Central America and South America from Sigma-Tau Pharmaceuticals, Inc. in 2014.

The patents and/or patent applications that relate to our product candidates include:

•JZP815. Through a collaboration agreement and an asset purchase agreement with Redx in 2019, we acquired a portfolio of U.S. and ex-U.S. patents and patent applications, including rights relating to compositions and methods of using JZP815. The portfolio contains a U.S. composition of matter patent relating to JZP815, which expires in 2035 (excluding any adjustments or extensions).

•JZP898. Through a license agreement with Werewolf in 2022, we obtained a license to a portfolio of U.S. and ex-U.S. patents and patent applications, including rights relating to compositions and methods of using JZP898. The portfolio contains a U.S. composition of matter patent relating to JZP898, which, if granted, expires in 2040 (excluding any adjustments or extensions).

In addition, we have rights to a number of trademarks and service marks, and pending trademark and service mark applications, in the U.S. and elsewhere in the world to further protect the proprietary position of our products. For a discussion of the challenges we face in obtaining or maintaining patent and/or trade secret protection, see the risk factors under the heading “Risks Related to Our Intellectual Property” in Part I, Item 1A of this Annual Report on Form 10‐K.

Government Regulation

As a global pharmaceutical company, our activities are subject to extensive regulation in the U.S., Europe and other countries where we do business. Regulatory requirements encompass the entire life cycle of pharmaceutical products, from R&D activities to marketing approval, manufacturing, labeling, packaging, adverse event and safety reporting, storage, advertising, promotion, sale, pricing and reimbursement, recordkeeping, distribution, importing and exporting. Regulations differ from country to country and are constantly evolving.

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Testing and Approval of Pharmaceutical Products

We are not permitted to market a product in a country until we receive approval from the relevant regulatory authority, such as FDA in the U.S. and the EC or the competent authorities of the EU member states. An application for marketing approval must contain information generated by the applicant, also called a sponsor, demonstrating the quality, safety and efficacy of the product candidate, including data from preclinical and clinical trials, proposed product packaging and labeling and information pertaining to product formulation and the manufacture and analytical testing of the API and the finished product.

In the U.S., FDA reviews and, if warranted, approves applications for marketing approval. The process for obtaining marketing approval in the U.S. for a drug or biologic product candidate generally includes:

•conducting preclinical laboratory and animal testing and submitting the results to FDA in an IND application requesting approval to test the product candidate in human clinical trials;

•conducting adequate and well-controlled human clinical trials to establish the safety and efficacy of the product candidate in the desired indication;

•submitting an NDA, sNDA, BLA or sBLA as appropriate, to FDA seeking approval for a specific indication; and

•completing inspections by FDA of the facilities where the product candidate is manufactured, analyzed and stored to demonstrate compliance with cGMP, and any requested FDA audits of the clinical trial sites that generated the data supporting the application.

Human clinical trials conducted before approval of a product generally proceed in three sequential phases, although the phases may overlap. In Phase 1, the initial introduction of the product candidate in humans, the product candidate is typically tested to assess metabolism, pharmacokinetics, pharmacological actions and tolerability, including side effects associated with increasing doses. Phase 2 usually involves clinical trials in a limited patient population to determine the effectiveness of the product candidate for a particular indication or indications, dosage tolerance and optimum dosage and to identify common adverse effects and safety risks. If a product candidate demonstrates evidence of effectiveness and an acceptable safety profile in Phase 2, Phase 3 clinical trials are undertaken to obtain additional information about clinical efficacy and safety in a larger number of patients. Clinical trials must be conducted in accordance with specific protocols, as well as FDA requirements related to conducting the trials and recording and reporting the results, commonly referred to as good clinical practices, to ensure that the resulting data are credible and accurate and that the trial participants are adequately protected. FDA enforces good clinical practices through periodic inspections of trial sponsors, clinical investigators and trial sites.

Once an NDA, sNDA, BLA or sBLA has been compiled and submitted, FDA performs an initial review before it accepts the application for filing. FDA may refuse to file an application and/or request additional information before acceptance. Once accepted for filing, FDA begins an in-depth review of the application. Under the current goals and policies agreed to by FDA under the PDUFA for a new molecular entity, FDA has ten months from the filing decision in which to complete its initial review of a standard application and respond to the applicant, and six months from the filing decision for a priority application. FDA does not always meet its PDUFA goal dates, and in certain circumstances, the PDUFA goal date may be extended.

FDA also has various programs, including fast track, priority review, breakthrough therapy and accelerated approval (Subpart H and E), RTOR pilot program, that are intended to expedite the process for reviewing certain applications and/or provide for approval on the basis of surrogate endpoints or restricted distribution. Generally, products may be eligible for one or more of these programs if they are intended for serious or life-threatening diseases or conditions, have potential to address unmet medical needs, or may provide meaningful benefit over existing treatments. In addition, a PRV may be used to obtain priority review by FDA for one of our future regulatory submissions. Modeyso was also granted fast track designations and priority review for the treatment of adult and pediatric patients 1 year of age and older with diffuse midline glioma harboring an H3 K27M mutation, which was granted accelerated approval in August 2025.

During its review of an application, FDA evaluates whether the product demonstrates the required level of safety and efficacy for the indication for which approval is sought and conducts the inspections and audits described above. FDA may also refer an application to an advisory committee, typically a panel of clinicians, for review, evaluation and a non-binding recommendation as to whether the application should be approved. When FDA completes its evaluation, it issues either an approval letter or a complete response letter. A complete response letter generally outlines what FDA considers to be the deficiencies in the application and may indicate that substantial additional testing or information is required prior to FDA approval of the product. If and when identified deficiencies have been addressed to FDA’s satisfaction after a review of the resubmission of the application FDA will issue an approval letter.

Even if a product is approved, the approval may be subject to limitations based on FDA’s interpretation of the data submitted in the application. For example, as a condition of approval, FDA may require the sponsor to agree to certain post-marketing requirements, such as conducting Phase 4, or post-approval, clinical trials to gain additional safety data or to

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document a clinical benefit in the case of products approved under accelerated approval regulations. FDA granted accelerated approval to Zepzelca for relapsed SCLC based on data from a Phase 2 trial and to Modeyso for diffuse midline glioma harboring an H3 K27M mutation with progressive diseases following prior therapy; both approvals are contingent upon verification and description of clinical benefit in a post-marketing clinical trial.

In addition, if FDA determines that a REMS is necessary to ensure that the benefits of the product outweigh the risks, a sponsor may be required to include a proposed REMS (either as part of the application or after approval), which may include a patient package insert or a medication guide to provide information to consumers about the product’s risks and benefits; a plan for communication to healthcare providers; or conditions on the product’s prescribing or distribution referred to as ETASU. Xywav and Xyrem are required to have a REMS. For more discussion regarding the Xywav and Xyrem REMS, see the risk factors under the headings “The distribution and sale of our oxybate products are subject to significant regulatory restrictions, including the requirements of a REMS, and these regulatory requirements subject us to risks and uncertainties, any of which could negatively impact sales of Xywav and Xyrem” and “Risks Related to Our Intellectual Property” in Part I, Item 1A of this Annual Report on Form 10‐K.

The EU and many individual countries have regulatory structures similar to the U.S. for conducting preclinical and clinical testing and applying for marketing approval or authorization, although specifics may vary widely from country to country. Clinical trials in the EU must be conducted in accordance with the requirements of the EU Clinical Trials Regulation and applicable good clinical practice standards.

In the EU, there are several procedures for requesting marketing authorization which can be more efficient than applying for authorization on a country-by-country basis. There is a “centralized” procedure allowing submission of a single MAA to EMA. If EMA issues a positive opinion, the EC will grant a centralized marketing authorization that is valid in all EU member states and three of the four European Free Trade Association countries (Iceland, Liechtenstein and Norway). The centralized procedure is mandatory for certain medicinal products, including orphan medicinal products and biotechnology-derived medicinal products, and optional for others. There is also a “decentralized” procedure allowing companies to file identical applications to several EU member states simultaneously for product candidates that have not yet been authorized in any EU member state and a “mutual recognition” procedure allowing companies that have a product already authorized in one EU member state to apply for that authorization to be recognized by the competent authorities in other EU member states. The U.K.’s withdrawal from the EU on January 31, 2020, commonly referred to as Brexit, has created uncertainty concerning the future relationship between the U.K. and the EU. Among the changes that have had a direct impact are that Great Britain (England, Scotland and Wales) is now treated as a third country. To mitigate the immediate impact of this in December 2020, the EU and U.K. reached an agreement in principle on the framework for their future relationship, the TCA. With regard to EU regulations, Northern Ireland continues to follow the EU regulatory rules. As part of the TCA, the EU and the U.K. recognize GMP, inspections carried out by the other party and the acceptance of official GMP documents issued by the other party. The TCA also encourages, although it does not oblige, the parties to consult one another on proposals to introduce significant changes to technical regulations or inspection procedures. Among the areas of absence of mutual recognition are batch testing and batch release. The U.K. has unilaterally agreed to accept EU batch testing and batch release; there is a list of approved countries for import into Great Britain, currently including EU and EEA countries, which require no import testing or U.K. “qualified person” release certification. However, the EU continues to apply EU laws that require batch testing and batch release to take place in the EU territory. This means that medicinal products that are tested and released in the U.K. must be retested and re-released when entering the EU market for commercial use. As regards marketing authorizations, Great Britain has introduced a separate regulatory submission process, approval process and a separate national marketing authorization. Northern Ireland, however, continues to be covered by the marketing authorizations granted by the EC.

The maximum timeframe for the evaluation of a MAA in the EU under the centralized procedure is 210 days, subject to certain exceptions and clock stops. An initial marketing authorization granted in the EU is valid for five years, with renewal subject to re-evaluation of the risk-benefit profile of the medicinal product. Once renewed, the authorization is usually valid for an unlimited period unless the national competent authority or the EC decides on justified grounds to proceed with one additional five-year renewal.

In the EU, if an applicant can demonstrate that comprehensive data on the efficacy and safety of the product under normal conditions of use cannot be provided due to certain specified objective and verifiable reasons, products may be granted marketing authorization “under exceptional circumstances.” A marketing authorization granted under exceptional circumstances is valid for five years, subject to an annual reassessment of conditions imposed by the EC. The marketing authorization in the EU for Defitelio was granted under exceptional circumstances because it was not possible to obtain complete information about the product due to the rarity of the disease and because ethical considerations prevented conducting a study directly comparing Defitelio with best supportive care or a placebo. As a result, the marketing authorization requires us to comply with a number of post-marketing obligations, including obligations relating to the manufacture of the drug substance and finished product, the submission of data concerning patients treated with the product collected through a third-party patient registry and the establishment of a multi-center, multinational and prospective observational patient registry to investigate the

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long-term safety, health outcomes and patterns of utilization of Defitelio during normal use. We are in the process of conducting the post-authorization study in the EU to provide further data on long-term safety, health outcomes and patterns of utilization of Defitelio in normal use.

Similar to the use of REMS in the U.S. to ensure that the benefits of a product outweigh its risks, in the EU and other countries we are required and may, in the future in relation to new products, be required to agree to post-marketing obligations or conditions in the marketing authorization for our products, to include a patient package insert or a medication guide to provide information to consumers about the product’s risks and benefits, to implement a plan for communication to healthcare providers, and to impose restrictions on the product’s distribution. For example, the marketing authorization in the EU for Vyxeos requires us to comply with certain manufacturing-related post-approval commitments.

After approval, certain changes to the approved product, such as adding new indications, making certain manufacturing changes, modifying a REMS, or making certain additional labeling claims, are subject to further regulatory review and approval. Obtaining approval for a new indication generally requires that additional clinical studies be conducted to demonstrate that the product is safe and effective for the new intended use. Such regulatory reviews can result in denial or modification of the planned changes, or requirements to conduct additional tests or evaluations that can substantially delay or increase the cost of the planned changes.

Manufacture of Pharmaceutical Products

The manufacturing process for pharmaceutical products is highly regulated, and regulators may shut down manufacturing facilities that they believe do not comply with regulations. We and the third party suppliers of our products are subject to cGMP, which are extensive regulations governing manufacturing processes, stability testing, recordkeeping and quality standards as defined by FDA, the EC, EMA, competent authorities of EU member states and other regulatory authorities. FDA also periodically inspects manufacturing facilities and the sponsor’s and manufacturer’s records related to manufacturing, and assesses compliance with cGMP. Following such inspections, FDA may issue notices on Form FDA 483 and warning letters. In addition to Form FDA 483 notices and warning letters, failure to comply with the statutory and regulatory requirements may result in suspension of manufacturing, product seizure, withdrawal of the product from the market, administrative, civil and criminal penalties, among other enforcement remedies both in the U.S. and in non-U.S. countries.

In the EU, a manufacturing authorization is required to manufacture medicinal products, and the manufacturing authorization holder must comply with various requirements set out in applicable EU laws, regulations and guidance. These requirements include compliance with EU cGMP standards when manufacturing products and their APIs, including APIs manufactured outside of the EU with the intention of importing them into the EU. In addition to inspection reports, manufacturers and marketing authorization holders may be subject to civil, criminal or administrative sanctions, including suspension of manufacturing authorization, in cases of non-compliance with the EU or EU member states’ requirements applicable to manufacturing.

Sales and Marketing of Pharmaceutical Products

Advertising and Promotional Activities

FDA regulates advertising and promotional activities for products in the U.S., requiring advertising, promotional materials and labeling to be truthful and not misleading, and products to be marketed only for their approved indications and in accordance with the provisions of the approved label. FDA actively investigates allegations of off-label promotion in order to enforce regulations prohibiting these types of activities. FDA routinely issues informal and more formal communications such as untitled letters or warning letters interpreting its authority over these matters. While such communications may not be considered final agency decisions, many companies may decide not to contest the agency’s interpretations so as to avoid disputes with FDA, even if they believe the claims they were making to be truthful, not misleading and otherwise lawful.

In the EU, the advertising and promotion of our products are subject to laws governing promotion of medicinal products, interactions with physicians, misleading and comparative advertising and unfair commercial practices. For example, applicable laws require that promotional materials and advertising in relation to medicinal products comply with the product’s SmPC as approved by the competent authorities in connection with a marketing authorization. The SmPC is the document describing the properties and the officially approved conditions of use of a medicine and providing information to physicians concerning the safe and effective use of the medicinal product. Promotional activity that does not comply with the SmPC is considered off-label and is prohibited in the EU. Other applicable laws at the EU level and in the individual EU member states also apply to the advertising and promotion of medicinal products, including laws that prohibit the direct-to-consumer advertising of prescription-only medicinal products and further limit or restrict the advertising and promotion of our products to the general public and to health care professionals. Violations of the rules governing the promotion of medicinal products in the EU could be penalized by administrative measures, fines and imprisonment.

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Fraud and Abuse

We are also subject to numerous fraud and abuse laws and regulations globally. In the U.S., there are a variety of federal and state laws restricting certain marketing practices in the pharmaceutical industry pertaining to healthcare fraud and abuse, including anti-kickback laws and false claims laws. Our sales, marketing, patient support and medical activities may be subject to scrutiny under these laws. The U.S. federal healthcare program Anti-Kickback Statute prohibits, among other things, knowingly and willfully offering, paying, soliciting or receiving anything of value to induce (or in return for) the referral of business, including the purchase, recommendation or prescription of a particular drug reimbursable under Medicare, Medicaid or other federally financed healthcare programs. The statute has been interpreted to apply to arrangements between pharmaceutical companies on one hand and patients, prescribers, purchasers and formulary managers on the other. Although there are a number of statutory exemptions and regulatory safe harbors protecting certain common manufacturer business arrangements and activities from prosecution and administrative sanction, the exemptions and safe harbors are drawn narrowly and are subject to regulatory revision or changes in interpretation by the DOJ and the OIG. Practices or arrangements that involve remuneration may be subject to scrutiny if they do not qualify for an exemption or safe harbor. For example, in November 2020, the OIG issued a Special Fraud Alert to highlight certain inherent risks of remuneration related to speaker programs sponsored by drug and device companies, which may not in all circumstances qualify under either safe harbor or statutory exception protection. The Special Fraud Alert sent a clear signal that speaker programs will be subject to potentially heightened enforcement scrutiny, in particular for those programs with certain characteristics identified as risk factors by the OIG, including meals exceeding modest value or where alcohol is made available; lack of substantive or new content presented; programs held at venues not conducive to the exchange of educational information; repeat attendees or attendees without a legitimate business interest; sales or marketing influence on speaker selection; and excessive speaker compensation. Violations of the federal Anti-Kickback Statute may be established without providing specific intent to violate the statute, and may be punishable by civil, criminal, and administrative fines and penalties, damages, imprisonment, and/or exclusion from participation in federal healthcare programs.

The federal civil False Claims Act prohibits, among other things, any person from knowingly presenting, or causing to be presented, a false or fraudulent claim for payment of federal funds, or knowingly making, or causing to be made, a false record or statement to get a false claim paid. A claim resulting from a violation of the federal Anti-Kickback Statute constitutes a false or fraudulent claim. The False Claims Act also permits a private individual acting as a “whistleblower” to bring actions on behalf of themselves and the federal government alleging violations of the statute and to share in any monetary recovery. Violations of the False Claims Act may result in significant financial penalties (including mandatory penalties on a per claim or statement basis), treble damages and exclusion from participation in federal health care programs.

Pharmaceutical companies are subject to other federal false claim and statements laws, some of which extend to non-government health benefit programs. For example, the healthcare fraud provisions under HIPAA impose criminal liability for, among other things, knowingly and willfully executing, or attempting to execute, a scheme to defraud any health care benefit program, including private third party payors, or falsifying or covering up a material fact or making any materially false or fraudulent statement in connection with the delivery of or payment for health care benefits, items or services. Violations of HIPAA fraud provisions may result in criminal, civil and administrative penalties, fines and damages, including exclusion from participation in federal healthcare programs.

The majority of individual states also have statutes or regulations similar to the federal Anti-Kickback Statute and the False Claims Act, which apply to items and services reimbursed under Medicaid and other state programs, or, in several states, apply regardless of the payor. Other states restrict whether and when pharmaceutical companies may provide meals to health care professionals or engage in other marketing-related activities, and certain states and cities require identification or licensing of sales representatives.

Other Post-Approval Pharmaceutical Product Regulation

Safety Reporting/Pharmacovigilance

FDA, EMA and other governmental authorities track information on side effects and adverse events reported during clinical studies and after marketing approval. We are required to file periodic safety update reports with the authorities concerning adverse events. If, upon review, an authority determines that any events and/or reports indicate a trend or signal, they can require a change in a product label, restrict sales and marketing, require post-approval safety studies, require a labor intensive collection of data regarding the risks and benefits of marketed products and ongoing assessments of those risks and benefits and/or require or conduct other actions, potentially including withdrawal or suspension of the product from the market. For example, if EMA has concerns that the risk-benefit profile of a product has changed, it can, following an investigation procedure, adopt an opinion advising that the existing marketing authorization for the product be varied or suspended and requiring the marketing authorization holder to conduct post-authorization safety studies. The opinion is then submitted for approval by the EC. Also, from time to time, FDA issues drug safety communications on its adverse event reporting system based on its review of reported adverse events.

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FDA and the competent authorities of the EU member states on behalf of EMA also periodically inspect our records related to safety reporting. Following such inspections, FDA may issue notices on FDA Form 483 and warning letters that could cause us to modify certain activities. An FDA Form 483 notice, if issued, can list conditions FDA investigators believe may have violated relevant FDA regulations or guidance. Failure to adequately and promptly correct the observation(s) can result in a warning letter or other regulatory enforcement action. Similarly, EMA’s Pharmacovigilance Risk Assessment Committee may propose to the CHMP that the marketing authorization holder be required to take specific steps. Non-compliance can lead to the variation, suspension or withdrawal of marketing authorization or imposition of financial penalties or other enforcement measures.

Sunshine Act and Transparency Laws

The Sunshine provisions require tracking of payments and transfers of value to physicians and teaching hospitals and ownership interests held by physicians and their families, and reporting to the federal government and public disclosure of these data. Since 2022, reporting has been required of information regarding payments and transfers of value provided to physician assistants, nurse practitioners, clinical nurse specialists, certified nurse anesthetists, and certified nurse-midwives. A number of states now require pharmaceutical companies to report expenses relating to the marketing and promotion of pharmaceutical products and to report gifts and payments to healthcare providers in the states. Government agencies and private entities may inquire about our marketing practices or pursue other enforcement activities based on the disclosures in those public reports.

Outside the U.S., interactions between pharmaceutical companies and physicians are also governed by strict laws, regulations, industry self-regulation codes of conduct and physicians’ codes of professional conduct. The provision of benefits or advantages to physicians to induce or encourage the prescription, recommendation, endorsement, purchase, supply, order or use of medicinal products, which is prohibited in the EU, is governed by the national anti-bribery laws of the EU member states, as described below in “Business—Government Regulation—Anti-Corruption Legislation” in this Part I, Item 1. Violation of these laws could result in substantial fines and imprisonment. Certain EU member states, or industry codes of conduct, require that payments made to physicians be publicly disclosed. Moreover, agreements with physicians must often be the subject of prior notification and approval by the physician’s employer, his/her competent professional organization, and/or the competent authorities of the individual EU member states. Failure to comply with these requirements could result in reputational risk, public reprimands, administrative penalties, fines or imprisonment.

Controlled Substance Regulations

The DEA is the U.S. federal agency responsible for domestic enforcement of the federal CSA and similar state and foreign laws based on the drug’s potential for abuse, among other factors. Controlled substances are subject to a high degree of regulation under the CSA, which establishes, among other things, certain registration, manufacturing quotas, security, recordkeeping, reporting, import, export and other requirements administered by the DEA. The DEA classifies controlled substances into five schedules. Schedule I substances have a high potential for abuse, have no currently “accepted medical use” in the U.S., lack accepted safety for use under medical supervision, and may not be prescribed, marketed or sold in the U.S. Pharmaceutical products approved for use in the U.S. may be classified as Schedule II, III, IV or V, with Schedule II substances considered to present the highest potential for abuse or dependence and Schedule V substances the lowest relative risk of abuse. The API of Xywav and Xyrem, oxybate salts, are regulated by the DEA as Schedule I controlled substances, and Xywav and Xyrem drug products are regulated as Schedule III controlled substances. Certain product candidates we are developing contain controlled substances as defined in the CSA. Drug products approved by FDA that contain cannabis or cannabis extracts may be controlled substances and, if so, will be rescheduled to Schedules II-V after approval or, like Epidiolex, removed completely from the schedules by operation of other laws.

The DEA limits the quantity of certain Schedule I and II controlled substances that may be manufactured and procured in the U.S. in any given calendar year through a quota system and, as a result, quotas from the DEA are required in order to manufacture and procure oxybate salts in the U.S. Accordingly, we require DEA quotas for Siegfried, our U.S. based sodium oxybate supplier, to manufacture sodium oxybate and for Patheon, our U.S.-based Xyrem supplier, to procure sodium oxybate from Siegfried in order to manufacture and supply us with Xyrem drug product. We also require DEA quotas for Patheon to manufacture and procure the API of Xywav oxybate salt. Xywav and Xyrem manufactured at our plant in Ireland enter the U.S. as Schedule III drugs and therefore do not require a DEA manufacturing or procurement quota.

As Schedule III drugs, Xywav and Xyrem are also subject to DEA and state regulations relating to the importation, manufacturing, storage, distribution and physician prescription procedures, including limitations on prescription refills. In addition, the third parties who perform certain activities related to our products that contain controlled substances, including manufacturing, distributing, dispensing and conducting clinical studies for Xywav and Xyrem, are required to maintain necessary DEA registrations and state licenses and comply with federal and state controlled substance requirements. The DEA periodically inspects facilities for compliance with its rules and regulations. For all controlled substances, there are potential criminal and civil penalties that apply for the failure to meet applicable legal requirements, and, in general, healthcare

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professionals may be required to have a federal and/or state license in order to handle, prescribe, or dispense controlled substances.

Other Regulations

There are many other requirements and restrictions in the U.S. and elsewhere imposed on pharmaceutical companies and their activities, including those related to the posting of information relating to clinical studies and their outcomes, the export and importation of products, required authorizations for distributors, the identification or licensing of sales representatives, restrictions on the ability of manufacturers to offer co-pay support to patients for certain prescription drugs, implementation of required compliance programs or marketing codes of conduct, protection of the environment, taxation and work safety. Non-compliance with such requirements may result in civil, criminal or administrative sanctions.

Anti-Corruption Legislation

Our business activities outside of the U.S. are subject to the FCPA, and similar anti-bribery or anti-corruption laws, regulations, industry self-regulation codes of conduct and physicians’ codes of professional conduct or rules of other countries in which we operate, including the U.K. Bribery Act. The FCPA and similar anti-corruption laws in other countries generally prohibit the offering, promising, giving, or authorizing others to give anything of value, either directly or indirectly, to U.S. or non-U.S. government officials in order to improperly influence any act or decision, secure an improper advantage, or obtain or retain business. The FCPA also requires public companies to make and keep books and records that accurately and fairly reflect the transactions of the company and to devise and maintain an adequate system of internal accounting controls. The U.K. Bribery Act prohibits giving, offering, or promising bribes to any person, including U.K. and non-U.K. government officials and private persons, as well as requesting, agreeing to receive, or accepting bribes from any person. In addition, under the U.K. Bribery Act, companies that carry on a business or part of a business in the U.K. may be held liable for bribes given, offered or promised to any person, including U.K. and non-U.K. government officials and private persons in any country, by employees and persons associated with the company in order to obtain or retain business or a business advantage for the company. Liability is strict, with no element of a corrupt state of mind, but a defense of having in place adequate procedures designed to prevent bribery is available under the U.K. Bribery Act and certain other laws; under the FCPA, it might be considered as a mitigating factor.

JAZZ US Equity

JAZZ · 10-K · period ended 2025-12-31

Item 1.Business

JAZZ US Equity☆

JAZZ · 10-K · period ended 2025-12-31

Item 1.Business

JAZZ US Equity