supn-20221231

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

FOR THE FISCAL YEAR ENDED December 31, 2022

FOR THE TRANSITION PERIOD FROM TO

COMMISSION FILE NUMBER: 001-35518

SUPERNUS PHARMACEUTICALS, INC.

(Exact name of registrant as specified in its charter)

(Address of Principal Executive Offices) (zip code)

(Registrant's telephone number, including area code)

SECURITIES REGISTERED PURSUANT TO SECTION 12(b) OF THE ACT:

Common Stock, $0.001 Par Value 54,376,904 SUPN NASDAQ Stock Market LLC

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 an 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. (Check one):

Large accelerated filer ☒ Accelerated filer ☐

Non-accelerated filer ☐ Smaller reporting company ☐

Emerging growth company ☐

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. Yes ☒ No ☐

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

As of June 30, 2022, the aggregate market value of the common stock held by non-affiliates of the registrant based on the closing price of the common stock on the NASDAQ Global Market was $1,545,750,083.

DOCUMENTS INCORPORATED BY REFERENCE

Certain portions of the registrant's definitive Proxy Statement for its 2023 Annual Meeting of Stockholders, which will be filed with the Securities and Exchange Commission not later than 120 days after the end of the registrant's 2022 fiscal year end, are incorporated by reference into Part III of this Annual Report on Form 10-K.

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SUPERNUS PHARMACEUTICALS, INC.

FORM 10-K

For the Year Ended December 31, 2022

TABLE OF CONTENTS

Page

PART I

Item 1. Business 4

Item 1A. Risk Factors 27

Item 1B. Unresolved Staff Comments 67

Item 2. Properties 67

Item 3. Legal Proceedings 67

Item 4. Mine Safety Disclosures 73

PART II

Item 6. Reserved 75

Item 7A. Quantitative and Qualitative Disclosures about Market Risk 88

Item 8. Financial Statements and Supplementary Data 89

Item 9A. Controls and Procedures 135

Item 9B. Other Information 136

PART III

Item 10. Directors, Executive Officers and Corporate Governance 137

Item 11. Executive Compensation 137

Item 14. Principal Accounting Fees and Services 137

PART IV

Item 15. Exhibits, Financial Statement Schedules 138

SIGNATURES

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Unless the content requires otherwise, the words "Supernus," "we," "our" and "the Company" refer to Supernus Pharmaceuticals, Inc. and/or one or more of its subsidiaries, as the case may be. These terms are used solely for the convenience of the reader. Supernus Pharmaceuticals, Inc. and each of its subsidiaries are distinct legal entities. For example, MDD US Operations, LLC, a wholly-owned indirect subsidiary of Supernus Pharmaceuticals, Inc., is the exclusive licensee and distributor of APOKYN in the United States and its territories. Adamas Operations, LLC ("Adamas Operations"), a wholly-owned indirect subsidiary of Supernus Pharmaceuticals, Inc., wholly owns the patents and patent applications related to GOCOVRI and Osmolex ER and has a license agreement with Supernus Pharmaceuticals, Inc., granting Supernus Pharmaceuticals, Inc. rights to market and sell GOCOVRI and Osmolex ER.

We, including our subsidiaries, are the owner/licensee of various U.S. federal trademark registrations (®) and registration applications (TM), including the following marks referred to in this Annual Report on Form 10-K, pursuant to applicable U.S. intellectual property laws: "Supernus®", "Microtrol®", "Solutrol®", "Trokendi XR®", "Oxtellar XR®", "Qelbree®", "XADAGO®", "MYOBLOC®", "APOKYN®", "GOCOVRI®", "Osmolex ER®", "Namzaric®", and the registered Supernus Pharmaceuticals logo.

All trademarks or trade names referred to in this Annual Report are the property of their respective owners. Solely for convenience, the trademarks and trade names in this Annual Report on Form 10-K are referred to without the ® and TM symbols, but such references should not be construed as any indicator that their respective owners will not assert, to the fullest extent under applicable law, their rights thereto.

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PART I

This Annual Report on Form 10-K contains forward-looking statements within the meaning of the Securities Exchange Act of 1934 and the Securities Act of 1933 that involve risks and uncertainties. Forward-looking statements convey our current expectations or forecasts of future events. All statements contained in this Annual Report other than statements of historical fact are forward-looking statements. Forward-looking statements include statements regarding our future financial position, business strategy, budgets, projected costs, plans, and objectives of management for future operations. The words "may," "continue," "estimate," "intend," "plan," "will," "believe," "project," "expect," "seek," "anticipate," "should," "could," "would," "potential," or the negative of those terms and similar expressions may identify forward-looking statements, but the absence of these words does not necessarily mean that a statement is not forward-looking.

These forward-looking statements include expectations regarding the Company's recent and future interactions and communications with the U.S. Food and Drug Administration (FDA) concerning the New Drug Applications (NDA) for SPN-830, the outcome of any additional device testing associated with the SPN-830 NDA submission, the potential approval of SPN-830 following resubmission, and the potential benefits and commercialization of SPN-830. In addition to the factors mentioned in this annual report, such risks and uncertainties include, but are not limited to, the Company's ability to sustain and increase its profitability; the Company's ability to raise sufficient capital to fully implement its corporate strategy; the implementation of the Company’s corporate strategy, including the successful identification and implementation of business development opportunities; the Company's future financial performance and projected expenditures; the Company's product research and development activities, including the timing and progress of the Company's clinical trials, and projected expenditures; the Company's ability to receive, and the timing of any receipt of, regulatory approvals to develop and commercialize the Company's product candidates; the Company's ability to protect its intellectual property and operate its business without infringing upon the intellectual property rights of others; the Company's expectations regarding federal, state and foreign regulatory requirements; the therapeutic benefits, effectiveness and safety of the Company's product candidates; the accuracy of the Company's estimates of the size and characteristics of the markets that may be addressed by its products and product candidates; the Company's ability to increase its manufacturing capabilities for its products and product candidates; the Company's projected markets and growth in markets; the early entry into the market of generic equivalents to all the Company's approved products; the Company's ability to develop successful product formulations that are accepted by patients, physicians, and payors; availability of potential funding sources; the Company's ability to meet its staffing needs; the Company's ability to comply with the Corporate Integrity Agreement and other risk factors set forth from time to time in the Company's filings with the Securities and Exchange Commission made pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934, as amended.

You should not place undue reliance on these forward-looking statements, which speak only as of the date of this report. All of these forward-looking statements are based on information available to us at this time, and we assume no obligation to update any of these statements. Actual results could differ from those projected in these forward-looking statements as a result of many factors, including those identified in the "Business," "Risk Factors," "Management's Discussion and Analysis of Financial Condition and Results of Operations" sections, and elsewhere in this Annual Report on Form 10-K. We urge you to review and consider the various disclosures made by us in this report and those detailed from time to time in our filings with the Securities and Exchange Commission that attempt to advise you of the risks and factors that may affect our future results.

ITEM 1. BUSINESS.

Overview

Supernus Pharmaceuticals, Inc. (the Company) is a biopharmaceutical company focused on developing and commercializing products for the treatment of central nervous system (CNS) diseases. Our diverse neuroscience portfolio includes approved treatments for epilepsy, migraine, attention-deficit hyperactivity disorder (ADHD), hypomobility in Parkinson’s Disease (PD), cervical dystonia, chronic sialorrhea, dyskinesia in PD patients receiving levodopa-based therapy, and drug-induced extrapyramidal reactions in adult patients. The Company is developing a broad range of novel CNS product candidates including new potential treatments for hypomobility in PD, epilepsy, depression, and other CNS disorders.

The Company was incorporated in Delaware, commenced operations in 2005, became publicly traded in 2012, and is listed on the NASDAQ Stock Exchange under the ticker symbol SUPN. Our principal executive offices are located in Rockville, Maryland. Our extensive expertise in product development has been built over the past 30 years: initially as a stand-alone development organization; then, as a United States (U.S.) subsidiary of Shire Plc (Shire, a subsidiary of Takeda Pharmaceutical Company Ltd.); then upon our acquisition of substantially all of the assets of Shire Laboratories, Inc. in 2005, as Supernus Pharmaceuticals.

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Adamas Acquisition and Reorganization

On October 10, 2021, the Company entered into an Agreement and Plan of Merger by and among the Company, Adamas Pharmaceuticals, Inc. (Adamas) and Supernus Reef, Inc., a Delaware corporation and a wholly-owned subsidiary of the Company (Purchaser) (Adamas Agreement). On November 24, 2021 (the Closing Date), the Company completed its purchase of all of the outstanding equity of Adamas, pursuant to the Adamas Agreement dated October 10, 2021, and the Purchaser was merged with and into Adamas (the Merger), with Adamas continuing as the surviving corporation in the Merger as a wholly-owned subsidiary of the Company (Adamas Acquisition). On the Closing Date, Adamas owned two marketed products: GOCOVRI (amantadine) extended-release capsules, the first and only FDA approved medicine indicated for the treatment of both "off" episodes and dyskinesia in patients with PD receiving levodopa-based therapy and as an adjunctive treatment to levodopa/carbidopa in patients with PD experiencing "off" episodes; and Osmolex ER (amantadine) extended-release tablets, approved for the treatment of PD and drug-induced extrapyramidal reactions in adult patients. Adamas also owns the right to receive royalties from Allergan plc for sales of Namzaric (memantine hydrochloride extended-release and donepezil hydrochloride) in the United States.

In the first quarter of 2022 and subsequent to the Adamas Acquisition, the Company completed a reorganization of the Adamas legal entities in an effort to obtain operational, legal and other benefits that also resulted in certain state tax efficiencies. The reorganization had no effect on the consolidated financial statements other than certain state tax efficiencies. Refer to Note 12, Income Tax (Benefit) Expense in Part II, Item 8—Financial Statements of this report.

Our Strategy

Our mission is to improve the lives of patients suffering from CNS diseases. Our vision is to be a leader in the CNS industry by developing and commercializing new medicines for the treatment of CNS diseases. Key elements of our strategy to achieve this vision include:

•Drive growth and profitability. Using dedicated sales and marketing resources in the U.S., we will continue to drive the revenue growth of our marketed products.

•Advance product candidates toward commercialization. Several product candidates in our pipeline are in early-to-late stage clinical testing, and moving toward being commercially available to patients.

•Continue to grow our pipeline. We will continue to evaluate and develop additional CNS product candidates that we believe have significant commercial potential through our internal research and development efforts.

•Target strategic business development opportunities. We are actively exploring a broad range of strategic opportunities. This includes in-licensing products and entering into co-promotion and co-development partnerships for our commercial products and product candidates.

Commercial Products

Our commercial products, including those sold by or through our subsidiaries, include:

Qelbree®

Qelbree (viloxazine extended-release capsules) is a novel non-stimulant product indicated for the treatment of ADHD in adults and pediatric patients 6 years and older. On April 2, 2021, the FDA approved Qelbree for the treatment of ADHD in pediatric patients 6 to 17 years of age. In May 2021, the Company launched Qelbree for pediatric patients in the U.S. On April 29, 2022, the FDA approved Qelbree for treatment of ADHD in adult patients. The Company launched Qelbree for adult patients in May 2022.

Trokendi XR®

Trokendi XR is indicated for (1) Epilepsy: initial monotherapy for the treatment of partial-onset and primary generalized tonic-clonic (PGTC) seizure in patients 6 years of age and older (1.1); adjunctive therapy for the treatment of partial-onset, primary generalized tonic-clonic seizures, or seizures associated with Lennox-Gastaut Syndrome in patients 6 years of age and older (1.2); and for (2) preventive treatment of migraine in patients 12 years of age and older. Trokendi XR is the first once-daily extended release topiramate product indicated for the treatment of epilepsy and the prophylaxis of migraine headaches in adults and adolescents in the U.S. market.

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The Company entered into settlement agreements with third parties permitting the sale of a generic version of Trokendi XR on or after January 1, 2023. For more information, refer to Part I, Item I—Business—Intellectual Property and Exclusivity in this annual Report on Form 10-K.

Oxtellar XR®

Oxtellar XR is indicated for treatment of partial-onset seizure in adults and children 6 years of age and older. Oxtellar XR is the first once-daily extended release oxcarbazepine product indicated for the treatment of epilepsy in the U.S. market. In 2013, we launched Oxtellar XR for adjunctive therapy in the treatment of partial-onset seizures in adults and children 6 to 17 years of age. In January 2019, we launched Oxtellar XR for monotherapy treatment of partial onset epilepsy seizures in adults and children 6 to 17 years of age.

GOCOVRI®

GOCOVRI (amantadine) extended release capsules is the first and only FDA-approved medicine indicated for the treatment of dyskinesia in patients with PD receiving levodopa-based therapy, with or without concomitant dopaminergic medications, and as an adjunctive treatment to levodopa/carbidopa in patients with PD experiencing "off" episodes.

GOCOVRI was approved by the FDA in August 2017 for treatment of dyskinesia and in February 2021 as an adjunctive treatment for "off" episodes. The February 2021 update to the label indication makes GOCOVRI the only medicine clinically proven and approved to reduce both "off" episodes and dyskinesia in PD patients taking a levodopa-based medication, resulting in a clinically meaningful increase in good "on" time without the need for a "trade-off' when managing motor complications.

GOCOVRI has been granted orphan drug exclusivity until August 24, 2024 for the treatment of dyskinesia in patients with PD receiving levodopa-based therapy with or without concomitant dopaminergic medications.

APOKYN®

APOKYN (apomorphine hydrochloride injection) is a product indicated for the acute, intermittent treatment of hypomobility or "off" episodes ("end-of-dose wearing off" and unpredictable "on-off" episodes) in patients with advanced PD. APOKYN's adjustable dose subcutaneous injection pen is designed to quickly and reliably reverse the effects of oral levodopa wearing off in patients with inadequately controlled PD.

XADAGO®

XADAGO (safinamide) is a once-daily product indicated as adjunctive treatment to levodopa/carbidopa in patients with PD who are experiencing "off" episodes. XADAGO is a monoamine oxidase B (MAO-B) inhibitor that works by blocking the catabolism of dopamine, which is believed to result in an increase in dopamine levels, and therefore a subsequent increase in dopaminergic activity in the brain.

XADAGO was approved by the FDA in March 2017.

Osmolex ER®

Osmolex ER (amantadine) extended release tablets is for the treatment of PD and drug-induced extrapyramidal reactions in adult patients.

Osmolex ER was approved by the FDA in February 2018.

MYOBLOC®

MYOBLOC (rimabotulinumtoxinB) is a product indicated for the treatment of cervical dystonia to reduce the severity of abnormal head position and neck pain associated with cervical dystonia in adults and treatment sialorrhea in adults. MYOBLOC is the only Type B toxin available on the market. MYOBLOC injections must be administered by a physician.

MYOBLOC was approved by the FDA in December 2000 for the treatment of adults with cervical dystonia.In August 2019, the FDA approved a supplemental Biologics License Application (sBLA) for MYOBLOC for the treatment of chronic sialorrhea in adults.

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Research and Development

We are committed to the development of innovative product candidates in neurology and psychiatry, including the following:

Product Candidate Indication Development NDA

SPN-820 Treatment-resistant depression Phase II

SPN-817 Focal seizures Phase I

We also engage in a variety of additional research and development effort including developing a pipeline of novel CNS product candidates for the treatment of various CNS conditions. We have devoted and continue to devote significant resources to research and development activities. We expect to incur significant expenses as we continue developing each of our product candidates through FDA approval or until the program terminates; and expanding product indications for approved products and intellectual property portfolio. Our expectations regarding our research and development programs are subject to the risks described under Item 1A—Risk Factors—Risks Related to Our Industry and Business, which includes the following risks among others — (1) The Company's financial condition and results of operations for fiscal year 2023 and beyond may be materially and adversely affected by the ongoing COVID-19 pandemic; and (2) Delays and failures in the completion of clinical development of our product candidates would increase our costs, delay, or limit our ability to generate revenues.

SPN-830 (apomorphine infusion device)

SPN-830 is a late-stage drug/device combination product candidate for the continuous treatment of motor fluctuations ("off" episodes) in PD patients that are not adequately controlled with oral levodopa and one or more adjunct PD medications. If approved, it would be the only continuous infusion of apomorphine available in the U.S. and an important step for PD patients that would have otherwise been candidates for potentially invasive surgical procedures, such as deep brain stimulation. Continuous slow infusion may also limit some of the side effects of a bolus injection of apomorphine.

In December 2021, we resubmitted the NDA to the FDA. In February 2022, we received a notice from the FDA that the resubmission of the NDA for SPN-830 was considered as a Standard Review and was assigned a PDUFA target action date in early October 2022. In October 2022, the FDA issued a Complete Response Letter (CRL) regarding the NDA for SPN-830. The CRL requires additional information and analysis related to the infusion device and drug product across several areas of the NDA including, but not limited to, labeling, product quality and manufacturing, device performance and risk analysis. In addition, the FDA mentions that approval of the NDA requires inspections that could not be completed in a timely manner due to COVID-19 travel restrictions. The CRL does not request additional efficacy and safety clinical studies. The FDA has made an initial determination that the amendment to the Company’s application in response to the CRL will be subject to a Class 2, or six-month, review timeline. In February 2023, the FDA granted the Company a Type C meeting request to discuss the CRL with the meeting scheduled in April 2023.

SPN-820 (NV-5138)

SPN-820 is a first-in-class, orally active small molecule that activates brain mTORC1 (mechanistic target of rapamycin complex 1), a gatekeeper of cellular metabolism and renewal. SPN-820 binds to and modulates sestrin, which senses amino acid availability in the brain, a potent natural activator of mTORC1.

Complex 1 of the mechanistic target of rapamycin (mTORC1) activity governs the pace and ability of the cell to synthesize protein and other cellular components. This complex may be suppressed in people suffering from depression. In other disease states such as severe depression, inadequate mTORC1 activity contributes to disease pathology by limiting energy utilization and protein synthesis, leading to impaired function. Multiple preclinical studies have shown that mTORC1 activation is required for the efficacy of many rapid-acting antidepressant compounds, including but not limited to modulators of the N-methyl-D-aspartic-acid (NMDA)-mediated signaling pathway like ketamine.

A Phase I trial demonstrated early proof of concept in which a single dose of SPN-820 showed a rapid and sustained improvement in core symptoms, with favorable safety and tolerability in patients with treatment resistant depression. We believe

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the novel MOA in depression may improve symptoms of depression in patients who have failed other agents.

An Investigational New Drug (IND) application was submitted to the FDA in September 2021. We initiated a Phase II multi-center, randomized double-blind placebo-controlled parallel design study of SPN-820 in adults with treatment resistant depression. The study will examine the efficacy and safety of SPN-820 over a course of five weeks of treatment in approximately 270 patients. The primary outcome measure is the change from baseline to end of treatment period on the Montgomery-Asberg Depression Rating Scale (MADRS) Total Score, a standard depression rating scale.

SPN-817 (huperzine A)

SPN-817 represents a novel mechanism of action (MOA) for an anticonvulsant. SPN-817 is a novel synthetic form of

huperzine A, whose MOA includes potent acetylcholinesterase inhibition, with pharmacological activities in CNS conditions such as epilepsy. The development will initially focus on the drug's anticonvulsant activity, which has been shown in preclinical models to be effective for the treatment of partial seizures and Dravet Syndrome. SPN-817 is in clinical development and has received Orphan Drug designation for both Dravet Syndrome and Lennox-Gastaut Syndrome from the FDA.

A Phase I, proof-of-concept trial is currently underway outside of the U.S. in adult patients with refractory complex partial seizures. We are studying the safety and pharmacokinetic profile of a new extended release formulation of non-synthetic SPN-817 (huperzine A). We are focused on completing and optimizing the synthesis process of the synthetic drug as well as developing a novel dosage form. Given the potency of SPN-817 (huperzine A), a novel extended release oral dosage form is critical to the success of this program because initial studies with the immediate release formulations of non-synthetic SPN-817 (huperzine A) have shown serious dose-limiting, side effects.

The Company has commenced an open-label Phase II clinical study of SPN-817 in patients with treatment-resistant seizures.

Sales and Marketing

We market our products through our own sales forces in the U.S. and seek strategic collaborations with other pharmaceutical companies to commercialize our products outside of the U.S. We have a commercial sales and marketing organization in the U.S. to support sales of our commercial products. We believe our current sales forces are effectively targeting healthcare providers to support and grow our current commercial products.

As a result of the acquisitions in 2021 and 2020, we established our commercial capabilities in the Parkinson's area with a focus on serving movement disorder specialists and other specialized health care providers in the U.S.

With the launches of Qelbree for both pediatric and adult patients, we expanded our sales efforts to market the commercial product to the relevant physician audience of psychiatrists, pediatricians, primary care physicians and allied health professionals. Our sales representatives who previously supported Trokendi XR and Oxtellar XR now devote their full efforts to the launch of Qelbree.

Customers

The majority of our product sales are to pharmaceutical wholesalers, specialty pharmacies, and distributors who, in turn, sell our products to pharmacies, hospitals, and other customers, including federal and state entities. The majority of sales of Oxtellar XR, Trokendi XR, Qelbree, and XADAGO are made to wholesalers and distributors. In addition, MYOBLOC is available for direct purchase by physicians and hospitals. The majority of sales of APOKYN and GOCOVRI are made to specialty pharmacies.

Each of our three major customers, AmerisourceBergen Drug Corporation, Cardinal Health, Inc., and McKesson Corporation, individually accounted for more than 25% of our total product revenue in 2022 and collectively accounted for more than 80% of our total product revenue in 2022.

Market and Competition

We are engaged in segments of the pharmaceutical industry that are highly competitive and rapidly changing. Many large pharmaceutical and biotechnology companies, academic institutions, governmental agencies, and other public and private research organizations are commercializing or pursuing the development of products for the same molecule, compound, or diseases that we are currently pursuing or may target in the future.

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ADHD

ADHD is a CNS disorder characterized by developmentally inappropriate levels of inattention, hyperactivity, and impulsivity. ADHD affects an estimated 6% to 9% of all school-age children, and an estimated 3% to 5% of adults in the U.S. An estimated 50% of children with ADHD continue to meet the criteria for ADHD into adolescence. Diagnosis of ADHD requires a comprehensive clinical evaluation based on identifying patients who exhibit the core symptoms of inattention, hyperactivity, and impulsivity. Although many patients may be inattentive, hyperactive, or impulsive, the level of severity and degree of functional impairment, and considerations as to what may be behind the underlying symptoms determine which patients meet the diagnosis and therefore should be treated for ADHD.

Qelbree is a novel nonstimulant taken once-daily for full-day exposure. Efficacy and symptom improvement was observed early in treatment in clinical studies. Also, it has a proven safety and tolerability profile, with no evidence of abuse potential in clinical studies. Qelbree is the first nonstimulant treatment for ADHD approved by the FDA in over a decade.

Competition in the U.S. ADHD market has increased with the commercial launch of several branded products in recent years, as well as the launch of generic versions of branded drugs, such as Adderall XR, Intuniv, Kapvay and Strattera. Treatment options for ADHD in the U.S. market can be broadly classified as either stimulant or as non-stimulant products.

Epilepsy

Epilepsy is a complex neurological disorder characterized by the spontaneous recurrence of unprovoked seizures, which are sudden surges of electrical activity in the brain that impair a person's mental and/or physical abilities. Adherence with drug treatment regimens is critically important to achieving effective control for patients with epilepsy. Non-adherence with anti-epileptic drug (AED) therapy is a serious issue and remains the most common cause of breakthrough seizures for patients. Not only is taking all prescribed doses critical to control breakthrough seizures, but the timing of when patients take their prescribed doses can also be crucial.

We believe extended release products, particularly Trokendi XR and Oxtellar XR, may offer important advantages in the treatment of epilepsy. The release profiles of extended release products can produce more consistent and steadier plasma concentrations as compared to immediate release products, potentially resulting in fewer side effects, better tolerability, fewer emergency room visits, improved efficacy, and fewer breakthrough seizures. In addition, Trokendi XR's and Oxtellar XR's once-daily dosing is designed to improve patient adherence over the current immediate release products, which must be taken multiple times per day. We believe a once-daily dosing regimen improves adherence, making it more probable that patients take their medication and maintain sufficient levels of medication in their bloodstreams. Extended release products may help patients improve adherence and, consequently, help patients enjoy a better quality of life.

Trokendi XR competes with all immediate release and extended release topiramate products, including Topamax, Qudexy XR, and their related generic products. Oxtellar XR competes with all immediate release oxcarbazepine products, including Trileptal and its related generic products. Both Oxtellar XR and Trokendi XR compete with other anti-epileptic products, both branded and generic. Many medications are used to treat epilepsy, including topiramate, oxcarbazepine, acetazolamide, brivaracetam, carbamazepine, clobazam, lacosamide, phenytoin, valproic acid, lamotrigine, gabapentin, levetiracetam phenobarbital, and zonisamide.

In addition, when considering treatment regimens for patients with epilepsy, neurologists and epileptologists take into consideration the MOA of the different AEDs that are available. By combining several different MOAs, it is sometimes possible to get significantly better seizure control. We acquired SPN-817, an antiepileptic, which we believe has an MOA different from that of other products and can therefore potentially represent a unique additional treatment alternative.

Migraine

Migraine is a painful, complex neurological disorder consisting of recurring painful attacks that can significantly disrupt time with loved ones, education, and careers. Migraine headaches are often characterized by throbbing pain, extreme sensitivity to light or sound, and potentially, nausea and vomiting. The World Health Organization categorizes migraine as one of the most disabling medical illnesses worldwide. The American Research Foundation categorizes migraine as the third most prevalent illness in the world, and nearly 1 in 4 U.S. households includes someone with migraines. Migraine is estimated to affect over 39 million individuals in the U.S.

As in epilepsy, we believe extended release products, particularly Trokendi XR, may offer important advantages for the treatment of migraines. Trokendi XR also competes with other products used for the prevention of migraine headaches. Most

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notably, this includes anti-CGRPs (calcitonin gene related peptide), which is a class of products first introduced in 2018; Botox; beta-blockers; valproic acid; and amitriptyline.

Parkinson's Disease

Parkinson's Disease is a progressive neurological disorder that is characterized by a loss of dopamine producing neurons in certain regions of the brain, causing symptoms like tremor, slowness of movement, stiffness, loss of balance, and lack of coordination. PD is the second most common progressive neurodegenerative disorder, affecting 1-2% of individuals 65 years and older. Patients with PD can also be affected with psychological symptoms such as anxiety, depression, aggression, and problems with cognition and memory. As the disease progresses, some patients may lose the ability to independently perform the tasks of daily living.

The most commonly prescribed medicine for PD is levodopa. PD patients are frequently prescribed levodopa to help replace dopamine, which is reduced in the brain. However, motor disabilities as a result of levodopa wearing off remain a significant problem for over half of PD patients. Patients in an "off" state, including those whose last dose of oral levodopa has worn off and whose next oral dose has not yet begun to take effect, can suffer from reduced coordination or mobility for several hours per day. Carbidopa may be used along with levodopa to improve its efficacy and reduce the amount of levodopa needed to control PD symptoms. There are a number of alternative adjunctive treatment options (FDA-approved and in clinical development) for Parkinson's patients, including various levodopa preparations, dopamine agonists, MAO-B inhibitors, and others.

APOKYN is given as needed as an adjunct to levodopa/carbidopa therapy in PD patients who experience "off" episodes. In well-controlled clinical studies, APOKYN injections were effective in treating "off" periods, as measured by the motor function subset of the Unified Parkinson's Disease Rating Scale (UPDRS). For patients for whom oral levodopa will not sufficiently control "off" periods, the Company has commercialized APOKYN, delivered via an injection pen. Patients taking APOKYN saw 95% of "off" episodes reversed, with improvement beginning as quickly as 10 minutes post-dosing in clinical studies. With the alternative of immobility and limited function, we believe the rapid and reliable reduction of "off" episode symptoms is of utmost importance to patients. APOKYN competes with all apomorphine hydrochloride products, including KYNMOBI. It also competes with other pro re nata (PRN) therapies such as Inbrija, and other adjunctive therapies, including NOURIANZ. APOKYN also competes with other products for the treatment of PD, both branded and generic, including levodopa products.

For patients who experience significant "off" time each day, the Company has developed a product candidate as a continuous infusion device (SPN-830) to deliver apomorphine subcutaneously. The infusion may reduce the variability in motor symptoms of PD and offer improved tolerability versus the acute injection route.

For patients not ready to try parenteral therapy, oral MAO-B inhibitors, such as XADAGO, may provide a decrease in "off" time of up to one hour per day when combined with appropriate levodopa therapy. In the XADAGO clinical trials, patients experienced more beneficial "on" time, a time when Parkinson's symptoms are reduced, without troublesome uncontrolled involuntary movement (dyskinesia), compared to those receiving a placebo. The increase in "on" time was accompanied by a reduction in "off" time and better scores on a measure of motor function assessed during "on" time than before treatment. XADAGO competes with other MAO-B inhibitors used to treat "off" episodes in PD, including rasagiline (AZILECT) and selegiline (Zelapar and EMSAM). XADAGO also competes with other products for the treatment of PD, both branded and generic, including levodopa products.

GOCOVRI (amantadine) extended-release capsules is the first and only FDA-approved medicine indicated for the treatment of dyskinesia in patients with PD receiving levodopa-based therapy, with or without concomitant dopaminergic medications, and as an adjunctive treatment to levodopa/carbidopa in patients with PD experiencing "off" episodes. It is also the only medicine clinically proven to reduce both dyskinesia and “off” periods. GOCOVRI, taken once daily at bedtime, provides an initial lag and a slow rise in amantadine concentration during the night, resulting in a high concentration from the morning and throughout the waking day. Additionally, in the clinical trials, the adjunctive use of GOCOVRI did not require changes to dopaminergic therapies. GOCOVRI has been granted orphan drug exclusivity until August 24, 2024 for the treatment of dyskinesia in patients with PD receiving levodopa-based therapy with or without concomitant dopaminergic medications.

Osmolex ER is an extended release tablet formulation that contains both immediate-release and extended-release amantadine, that is dosed once daily in the morning. We believe Osmolex ER’s once-daily morning dose offers a more convenient option by reducing the number of pills a patient must take each day, which may improve patient compliance with treatment regimens. While Osmolex ER is bioequivalent to immediate-release amantadine, the product provides a consistent delivery of amantadine throughout the day. Peak serum drug concentration conveniently occurs in the middle portion of a patient’s day when the drug is administered in the morning.

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According to their prescribing information, neither GOCOVRI nor Osmolex ER are interchangeable with other amantadine immediate- or extended-release products for their respective approved indications.

Cervical Dystonia

Cervical dystonia, also known as spasmodic torticollis, is a condition characterized by involuntary muscle contractions in the neck, which cause the head to twist uncontrollably into an abnormal, often painful position. It is a rare disorder, most often presenting in middle age, whose symptoms begin gradually, worsen, and then plateau over a period of months. Estimates of the prevalence of cervical dystonia vary considerably, from 20 to 4,100 per million individuals. Injections of botulinum toxin into affected neck muscles can create temporary relief from symptoms.

In well-controlled studies, botulinum toxins like MYOBLOC have been shown to improve symptoms as measured on the Toronto Western Spasmodic Torticollis Rating Scale, including pain. Based on clinical studies, MYOBLOC injections offer patients struggling with painful cervical dystonia symptoms relief as early as two weeks after injection, with the duration of effect between 12-16 weeks.

MYOBLOC is the only available botulinum toxin B, whereas other available toxins are type A. MYOBLOC competes with type A toxins such as Botox, Dysport, and Xeomin. MYOBLOC also competes with oral agents used to treat cervical dystonia, including generic baclofen, anticholinergics, benzodiazepines, and tetrabenazine.

Sialorrhea

Sialorrhea can occur in conjunction with several neurologic disorders, such as amyotrophic lateral sclerosis (ALS), cerebral palsy (CP), PD, or as a side effect of some medications. It is characterized by overactive salivary glands. In adults, PD is the most common cause of sialorrhea, with 70%–80% of PD patients experiencing symptoms. In 30%–80% of schizophrenic patients taking clozapine, sialorrhea is evident. In addition to being embarrassing, complications of sialorrhea include aspiration, infection, skin breakdown, and bad odor.

MYOBLOC competes with Xeomin (incobotulinumtoxinA) for the treatment of sialorrhea in adults. Other pharmacologic treatments used to treat sialorrhea include generic glycopyrrolate tablets as well as behavior modification.

Manufacturing

We currently depend on third-party commercial manufacturing organizations (CMOs) for all manufacturing operations, including the production of raw materials, dosage form product, and product packaging. This encompasses products for commercial use, as well as some products for preclinical and clinical research. We do not own or operate manufacturing facilities for the production of any of our product candidates beyond that used in Phase II clinical trials, nor do we have plans to develop our own manufacturing operations in the foreseeable future to support Phase III clinical trials or support commercial production. We currently employ internal resources to manage our manufacturing contractors.

We have agreements with CMOs headquartered North America, including: Patheon Pharmaceuticals, Inc. (a subsidiary of Thermo Fisher Scientific Inc.), Packaging Coordinators, Inc., Aphena Pharma Solutions, and Catalent Pharma Solutions, Europe, and Asia for the manufacturing and packaging of some of our commercial products, including those of our subsidiaries, as well as for our pipeline product candidates. For Qelbree, Trokendi XR, GOCOVRI, and Oxtellar XR we currently rely on third-party CMOs for the manufacturing and packaging of final commercial products. We rely on third-party CMOs in Asia for the manufacturing of bulk drug substance for Trokendi XR and Oxtellar XR and rely on a third-party CMO in Europe for the raw materials and manufacturing of Qelbree and GOCOVRI. With respect to GOCOVRI, we have an additional manufacturer of bulk drug substance. These CMOs offer a comprehensive range of contract manufacturing and packaging services.

We purchase APOKYN, MYOBLOC, XADAGO, and Osmolex ER as finished goods. APOKYN is manufactured and packagedin Europe for the U.S. market and is supplied to us by our licensing partner, Britannia. Britannia (a subsidiary of Stada Arzneimittel AG) also supplies injectable apomorphine to the European market under the brand name Apo-go. MYOBLOC is manufactured and packaged in Europe by Merz GmbH & Co. KGaA (Merz). Under the contract manufacturing agreement with Merz for the manufacture and supply of MYOBLOC, the Company has an annual minimum purchase requirement of MYOBLOC amounting to an estimated €3.9 million. XADAGO is manufactured and packaged in Europe by Zambon S.p.A. (Zambon). Osmolex ER is manufactured and packaged in the U.S. by Osmotica Pharmaceutical US LLC (Osmotica), which is the sole manufacturer of Osmolex ER and a subsidiary of Osmotica Pharmaceuticals plc.

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Refer to Part I, Item 1A—Risk Factors—If we fail to produce our products and product candidates in the volumes that we require on a timely basis or fail to comply with stringent regulations applicable to pharmaceutical drug manufacturers, we may face delays in the development and commercialization of our products and product candidates or be required to withdraw our products from the marketfor risks associated with manufacturing and supply of our products and product candidates.

Our Proprietary Technology Platforms

We have a successful track record of developing and launching novel products by applying proprietary formulation technologies to known drugs to improve their side effect profile or improve patient adherence. In addition, we have developed new indications for existing therapies. Our key proprietary technology platforms include: Microtrol, Solutrol, and EnSoTrol. These technologies have been utilized to create novel, customized product profiles designed to enhance efficacy, reduce the frequency of dosing to improve patient adherence and improve tolerability. Our technologies have been used to create ten commercial products, including our products: Qelbree, Trokendi XR and Oxtellar XR; Adderall XR (developed for Shire); Intuniv (developed for Shire); Mydayis (developed for Shire); Orenitram (developed for United Therapeutics Corporation); and Namzaric (developed for Allergan plc).

We are also engaged in generating and assessing New Chemical Entities (NCEs). These NCEs are generated by leveraging our expertise in structure function relationships in active molecules. Our NCEs are being assessed in preclinical pharmacology models for CNS activity and are advancing towards Investigational New Drug application (IND), enabling toxicology studies to support potential future clinical investigation.

Intellectual Property and Exclusivity

Overview

We, including our subsidiaries, continue to build our intellectual property portfolio to provide protection for our technologies, products, and product candidates. We, including our subsidiaries, seek patent protection, where appropriate, both in the U.S. and internationally for products and product candidates.

Our policy is to protect our innovations and proprietary products, and that of our subsidiaries, by, among other things, filing patent applications in the U.S. and abroad, including Europe, Canada, and other countries when appropriate. We, including our subsidiaries, also rely on trade secrets, know-how, proprietary knowledge, continuing technological innovation, and in-licensing opportunities to develop and maintain our proprietary position. Neither we, nor our subsidiaries can be sure that patents will be granted with respect to our pending patent applications or with respect to any patent applications filed by us, or any of our subsidiaries in the future, nor can we be sure that any of our existing patents or any patents that may be granted to us, or any of our subsidiaries in the future will be commercially useful in protecting our technology, our products, or those of our subsidiaries. Neither we, nor any of our subsidiaries can be sure that any patents, if granted, will sustain a legal challenge.

Patent Portfolio

Our commercial products, including those of our subsidiaries, covered by active patents include Trokendi XR, Oxtellar XR, Qelbree, GOCOVRI, Osmolex ER and XADAGO. We, or our subsidiaries, own all of the issued patents for Trokendi XR, Oxtellar XR, Qelbree, GOCOVRI, Osmolex ER, as well as the pending U.S. patent applications for Oxtellar XR, Qelbree, GOCOVRI, and Osmolex ER. We have a license from Zambon for the U.S. patents that cover XADAGO.

The Company has ongoing litigations concerning Trokendi XR, Oxtellar XR and XADAGO. For more information, refer to Part I, Item 3—Legal Proceedings in this annual Report on Form 10-K.

Qelbree

We have three families of pending U.S. non-provisional and foreign counterpart patent applications for Qelbree. Patents, if issued, could expire from 2029 to 2033. We have patents issued in the U.S., Canada, and certain countries in Europe covering a method of treating ADHD using viloxazine hydrochloride. In a second family, covering the novel synthesis process of the active ingredient, we have patents issued in the U.S. as well as in certain foreign countries. In a third family, we have four patents issued in the U.S. covering modified release formulations of viloxazine hydrochloride, three of which cover Qelbree. We also have patents issued in certain foreign countries. We own all of the issued patents and the pending patent applications.

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Trokendi XR

We currently have 10 U.S. patents that cover Trokendi XR. We own all of the issued patents. We also own additional foreign patents for extended release topiramate. The ten issued U.S. patents covering Trokendi XR will expire no earlier than 2027.

The Company has entered into settlement agreements with third parties, permitting the sale of a generic version of Trokendi XR on or after January 1, 2023.

Oxtellar XR

Our extended release oxcarbazepine patent portfolio currently includes 13 U.S. patents, ten of which cover Oxtellar XR. The ten issued U.S. patents covering Oxtellar XR will expire no earlier than 2027. We own all of the issued patents and the pending U.S. patent applications. We also own additional foreign patents for extended release oxcarbazepine.

XADAGO

As an NCE, XADAGO was under the 5-year FDA exclusivity period that expired on March 21, 2022. The patent portfolio covering XADAGO has three U.S. patents licensed from Zambon. These patents will expire from 2027 to 2031.

GOCOVRI

The patent portfolio covering GOCOVRI includes 18 U.S. patents. We have additional pending applications containing method and composition claims relating to the pharmacokinetic profile and dosing, and formulations of amantadine extended release. The issued patents expire through 2038. These patents and patent applications are owned by Adamas Operations and, as of the first quarter of 2022 are licensed to Supernus Pharmaceuticals, Inc. We, through our subsidiary Adamas Operations, own additional foreign patents and patent applications covering amantadine extended release.

Prior to our acquisition of Adamas, Adamas entered into settlement agreements with third parties, permitting the sale of a generic version of GOCOVRI (amantadine) extended release capsules (including for any new indications approved under the GOCOVRI NDA) on or after March 4, 2030, or earlier under certain circumstances.

Osmolex ER

Osmolex ER is covered for its FDA-approved indications by 18 issued U.S. patents and additional applications containing method and composition claims relating to the pharmacokinetic profile and dosing, and formulations of amantadine extended release. These issued patents expire through 2038. These patents and patent applications are wholly owned by Adamas Operations and, as of the first quarter of 2022 are licensed to Supernus Pharmaceuticals, Inc. Adamas Operations also owns additional foreign patents covering Osmolex ER.

Namzaric

Namzaric is covered by 19 U.S. patents containing method and compositions claims relating to the pharmacokinetic profile and dosing of memantine. These patents expire as late as 2029. Namzaric is currently marketed by Allergan plc under an exclusive license agreement between Adamas Pharmaceuticals LLC (Adamas Pharmaceuticals) and Forest Laboratories Holdings Limited ("Forest"), an indirect, wholly-owned subsidiary of Allergan plc (collectively, "Allergan") in the United States. Adamas Pharmaceuticals also owns additional foreign patents and patent applications covering Namzaric.

SPN-830 (apomorphine infusion device)

Our SPN-830 development program is potentially eligible to receive the Orphan Drug Designation in the U.S. If such designation is granted by the FDA, SPN-830 would receive 7 years of U.S. exclusivity from the time of approval by the FDA.

SPN-817 (huperzine A)

We have two U.S. patents licensed from Harvard University covering the method of treating seizures to potentially cover our SPN-817 development program. We have one patent issued in the U.S. and one in China relating to extended release formulations of huperzine. We additionally have pending patent applications in the U.S. and certain foreign countries.

SPN-817 has received Orphan Drug designation for both Dravet Syndrome and Lennox-Gastaut Syndrome from the FDA.

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SPN-820 (NV-5138)

Under the terms of the April 2020 Development Agreement with Navitor, we have an exclusive option to license or acquire NV-5138 in all world territories, prior to initiation of the Phase III clinical program.

Other Intellectual Property Rights

We, including our subsidiaries, seek trademark protection in the U.S. and internationally, where available and when appropriate. We, including our subsidiaries, have filed for trademark protection for several marks, which are used in connection with our pharmaceutical research and development collaborations as well as with our products and those of our subsidiaries. We or our subsidiaries are the owner/licensee of various U.S. federal trademark registrations (®) and registration applications (TM), including the following marks referred to in this Annual Report on Form 10-K, pursuant to applicable U.S. intellectual property laws: "Supernus®", "Microtrol®", "Solutrol®", "Trokendi XR®", "Oxtellar XR®", "Qelbree®", "XADAGO®", "MYOBLOC®", "APOKYN®", "GOCOVRI®", "Osmolex ER®", "Namzaric®", and the registered Supernus Pharmaceuticals logo.

From time to time, we, including our subsidiaries may find it necessary or prudent to obtain licenses from third party IP holders. Where licenses are readily available at a reasonable cost, such licenses are considered a normal cost of doing business. In other instances, however, we or our subsidiaries may use the results of freedom-to-operate inquiries and internal analyses to guide our early-stage research away from areas where we are likely to encounter obstacles in the form of third party IP. For example, where a third party holds relevant IP and is a direct competitor, a license might not be available on commercially reasonable terms or at all. We, and our subsidiaries, strive to identify potential third party IP issues in the early stages of our research programs in order to minimize the cost and disruption of resolving such issues.

To protect our competitive position and that of our subsidiaries, it may be necessary to enforce our patent rights through litigation against infringing third parties. See Part I, Item 3—Legal Proceedings. Litigation to enforce our own patent rights or those of our subsidiaries is subject to uncertainties that cannot be quantified in advance. In the event of an adverse outcome in litigation, we or our subsidiaries could be prevented from commercializing a product or precluded from using certain aspects of our technology platforms. This could have a material adverse effect on our business or that of our subsidiaries. In addition, litigation involving our patents or those of our subsidiaries carries the risk that one or more of our patents or those of our subsidiaries will be held invalid (in whole or in part; on a claim-by-claim basis) or held unenforceable. Such an adverse court ruling could allow third parties to commercialize products or use technologies that are similar to ours and then compete directly with us, without compensation to us or our subsidiaries. In addition, third parties could allege that our products or those of our subsidiaries infringe their intellectual property rights and pursue legal action against the Company or any of its subsidiaries. See Part I, Item 1A—Risk Factors for risk factors related to intellectual property.

U.S. Patent Application Process

The U.S. patent system permits the filing of provisional and non-provisional patent applications. A non-provisional patent application is submitted to the United States Patent and Trademark Office (USPTO) and can mature into a patent once the USPTO determines that the claimed invention meets the standards for patentability. The term of individual patents depends upon the legal term of the patents in the countries in which they are obtained. In most countries in which we file, the patent term is 20 years from the earliest date of filing a non-provisional patent application. In the U.S., a patent's term may be lengthened via a patent term adjustment (PTA), which compensates a patentee for administrative delays by the USPTO in granting a patent. Because of a recent court decision in which the USPTO erred in calculating the PTA by denying the patentee a portion of the patent term to which it was entitled, the USPTO is under greater scrutiny regarding its calculations of PTAs.

Alternatively, a patent's term may be shortened if a patent is terminally disclaimed over another patent.

In evaluating the patentability of a claimed invention, the filing date of a non-provisional patent application is used by the USPTO to determine what information constitutes prior art. If certain requirements are satisfied, a non-provisional patent application can claim the benefit of the filing date of a previously filed provisional patent application. In such an instance, the filing date accorded to the provisional patent application may supersede information that otherwise could preclude the patentability of an invention.

The term of a patent that covers an FDA-approved drug may also be eligible for patent term extension (PTE). This permits the patent term to be extended as compensation for that portion of a patent term lost during the FDA regulatory review process. The Drug Price Competition and Patent Term Restoration Act of 1984, or the Hatch-Waxman Amendments, permits a PTE of up to five years beyond the expiry date of the patent. The length of the PTE is related to the length of time the drug is under FDA review. However, the patent extension cannot extend the remaining term of a patent beyond a total of 14 years from

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the date of product approval. Only one patent for an approved drug may be extended. Similar provisions to extend the term of a patent that covers an approved drug are available in Europe and other foreign jurisdictions.

In the future, if and when our pharmaceutical products receive FDA or other regulatory approval, we may be able to apply for PTEs on patents covering those products. Depending upon the timing, duration, and specifics of FDA approval and the issuance of a U.S. patent, we may obtain limited patent term restoration.

Collaborations and Licensing Arrangements

We, including our subsidiaries, obtained exclusive licenses from third parties for proprietary rights to support our, and our subsidiaries', commercial products and product candidates. Under these in-licensing agreements, we or our subsidiaries may be required to pay certain amounts upon the achievement of defined milestones. If these products are ultimately commercialized, we or the applicable subsidiary are also obligated to pay royalties to third parties, computed as a percentage of net product sales, for each respective product under a license agreement.

We, including our subsidiaries, also have entered into out-licensing agreements to license our intellectual property and technology or that of our subsidiaries to third parties. Under these out-license agreements, we or our subsidiaries may be entitled to receive certain amounts upon the achievement of defined milestones and royalties from third parties, generally computed as a percentage of net product sales, for each respective product under a license agreement.

APOKYN and SPN-830 (apomorphine infusion device)

In January 2016, we entered into an Amended and Restated Distribution, Development, Commercialization, and Supply Agreement with Britannia that grants us certain intellectual property and product rights in relation to APOKYN, including the right to use and market APOKYN in the United States (Territory). Additionally, under the agreement, Britannia retains certain intellectual property and product rights in relation to APOKYN, including the right to use and market APOKYN in the rest of the world, excluding the United States. Under the Agreement, Britannia has an obligation to supply us with APOKYN for our marketing and sale of the product.

Under the agreement, we are obligated to pay Britannia a royalty based upon U.S. net sales, adjusted for other product related costs for APOKYN, SPN-830 and any other commercial products jointly developed under the agreement. The parties have also agreed to a cost sharing arrangement for the development of new products beyond APOKYN. Under the agreement, we are obligated to pay more than half of the related costs associated with the development of SPN-830 or other new products that are commercialized solely by the Company in the U.S. For costs associated with new products that are commercialized both inside and outside the Territory, we are obligated to pay less than half of related costs.

We have agreed to use commercially reasonable efforts to develop and commercialize products under the agreement. The initial 15 year term of the agreement is subject to automatic renewal periods unless canceled by either party. Either party may terminate the agreement under certain circumstances, including a material breach of the agreement by the other.

XADAGO

In February 2016, we entered into a License and Distribution Agreement and a Supply Agreement with Zambon. Under the License and Distribution Agreement, we are the exclusive distributor of XADAGO in the U.S. and we are prohibited from selling or distributing in the U.S. certain product that compete with XADAGO. Also, Zambon is eligible to receive up to $30.0 million in future payments upon the achievement of sales-based milestones, which are based upon specified annual net product sales of XADAGO in the U.S. During the term of the License and Distribution Agreement, we are also obligated to pay a royalty on net product sales of XADAGO in the U.S. In the event that XADAGO annual net sales exceed the specified U.S. annual net product sales thresholds, the royalty percent increases and could go as high as the mid-teens.

Under the Supply Agreement, we must purchase from Zambon and Zambon must provide to us all XADAGO finished products for the U.S. market.

We have agreed to use commercially reasonable efforts to develop and commercialize XADAGO under the agreement. Either party may terminate the agreement under certain circumstances, including a material breach of the agreement by the other.

MYOBLOC

In May 2004, we entered into an asset purchase agreement with Elan Pharmaceuticals (Elan agreement), now a subsidiary of Perrigo Company (Perrigo). Under the Elan agreement, we own the worldwide rights to MYOBLOC and pay a low double digit royalty to Perrigo based on U.S. annual net sales of MYOBLOC. If MYOBLOC is approved in the U.S. for cosmetic

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use, Perrigo is eligible to receive a milestone payment and the royalty rate will become subject to certain reductions based on cosmetic use net sales. Under a settlement agreement between Perrigo and Allergan, certain amounts of the royalty are owed to Allergan. We also have the right under the Elan agreement to make use of, develop and offer for sale worldwide products containing Botulinum Toxin Type B. The Elan agreement may not be terminated for convenience.

We also have an agreement with Elan and Eisai related to the marketing and distribution of NerBloc in Japan by Eisai. We also have the right under the agreement to make use of, develop and offer for sale in Japan human pharmaceutical drugs containing Botulinum Toxin Type B. This agreement will terminate upon certain conditions relating to Perrigo's patent rights and the commercial launch of products with respect to cervical dystonia and indications other than cervical dystonia.

We have a contract manufacturing agreement with Merz Pharma GmbH & Co. KGaA (Merz) for the manufacture and supply of MYOBLOC and NerBloc (Merz Agreement). Pursuant to the Merz Agreement, Merz is required to provide a dedicated manufacturing facility including a stand-alone building, dedicated clean room suites, dedicated manufacturing and purification equipment, and filling and packaging production lines (collectively, the manufacturing facility) to manufacture finished products. The Merz Agreement will expire in July 2027, unless the Company and Merz mutually agree to extend the term. The Merz Agreement may not be terminated for convenience. Under the terms of the Merz Agreement, the Company is required to purchase a minimum quantity of finished products on an annual basis. This minimum purchase requirement represents the in-substance fixed contract consideration associated with the dedicated manufacturing facility. The Company has an annual minimum purchase quantity requirement of finished products.

Osmolex ER

Our subsidiary Adamas Operations has the global rights to Osmolex ER. Pursuant to the Asset Purchase Agreement with Osmotica Pharmaceutical US LLC and Vertical Pharmaceuticals LLC (Osmotica) entered into on December 1, 2020 (transaction closed on January 4, 2021) both parties gave each other mutual releases and agreed to dismiss their respective claims relating to certain patent litigation; Adamas Operations acquired the global rights to Osmolex ER and existing inventory and the assumption of certain liabilities; and Osmotica agreed not to engage in the development, manufacture, or sale of any product in the U.S. that is a generic version of any dosage strength of Osmolex ER for a period of five years from the closing of the Asset Purchase Agreement.

SPN-817 (huperzine A)

In September 2018, we entered into a merger agreement to acquire Biscayne Neurotherapeutics (Biscayne), a privately-held company developing a novel treatment for epilepsy (SPN-817). Through this agreement, we obtained worldwide rights, excluding certain markets in Asia where rights have been previously out-licensed, to SPN-817. SPN-817 has received Orphan Drug designation from the FDA for the treatment of Dravet Syndrome, a severe form of childhood epilepsy and Lennox-Gastaut Syndrome. We may be obligated to pay up to $73 million to the prior Biscayne security holders if certain development milestones are achieved and up to an additional $95 million if certain sales milestones are achieved. In addition, we will be obligated to pay a low single digit royalty on net sales to the prior Biscayne security holders and any applicable royalties to third parties for the use of in-licensed IP. The maximum combined royalty we will pay to all parties on net product sales is approximately 12%, depending on the IP covering the commercial product and the applicable tiered sales levels.

SPN-820 (NV-5138)

In April 2020, we entered into a Development and Option Agreement with Navitor to collaborate on a clinical development program for NV-5138 (SPN-820), Navitor's mTORC1 activator. Under the terms of the agreement, the Company and Navitor will jointly conduct a Phase II clinical program in TRD. We will pay the costs of Phase II development up to $50 million, plus certain costs associated with nonclinical development and formulation. In addition, Navitor has granted the Company an exclusive option to license or acquire NV-5138 in all world territories, prior to initiation of the Phase III clinical program. We paid Navitor a one time, nonrefundable, and non-creditable fee of $10 million for the option to acquire or license NV-5138 (SPN-820) and made a $15 million equity investment representing approximately 13% ownership in Navitor. In December 2021, we received a $12.9 million cash distribution pursuant to our ownership position in Navitor LLC following the sale of one of its subsidiaries. There are certain additional payment amounts that could be incurred by the Company. These costs are contingent upon Navitor and the Company achieving defined development milestones.

Total payments, exclusive of royalty payments on net sales of NV-5138 and development costs under the agreement, have the potential to reach $410 million to $475 million, which includes the upfront payment of $25 million paid in 2020, an additional license or acquisition fee depending on whether the Company ultimately licenses or acquires NV-5138, and subsequent clinical, regulatory and sales based milestone payments. We also will have the first right of refusal for any compound with a similar MOA to NV-5138 on mTORC1 in the central nervous system.

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See Part II, Item 8, Financial Statements and Supplementary Data, Note 5, Investments, in the Notes to the Consolidated Financial Statements.

Namzaric

Namzaric (memantine hydrochloride extended release and donepezil hydrochloride) capsules for the treatment of moderate to severe dementia of an Alzheimer's type is currently marketed by Allergan plc under an exclusive license agreement between Adamas Pharmaceuticals and Forest Laboratories Holdings Limited ("Forest"), an indirect, wholly-owned subsidiary of Allergan plc (collectively, "Allergan") in the United States. Adamas Pharmaceuticals receives royalties on net sales of Namzaric from May 2020. Allergan is responsible for all manufacturing related to Namzaric.

In November 2012, Allergan was granted an exclusive license, with right to sublicense, certain of Adamas Pharmaceuticals' intellectual property rights relating to human therapeutics containing memantine in the United States. In connection with these rights, Allergan markets and sells Namzaric (memantine and donepezil hydrochlorides) extended-release capsules and NAMENDA XR (memantine hydrochloride) extended release capsules for the treatment of moderate to severe dementia related to Alzheimer's disease.

Adamas Pharmaceuticals is entitled to receive royalties on net sales in the United States by Allergan, its affiliates, or any of its sublicensees of controlled-release versions of memantine products covered by the terms of the license agreement. Allergan's obligation to pay royalties with respect to fixed-dose memantine-donepezil products, including Namzaric, continues until the later of (i) 15 years after the commercial launch of the first fixed-dose memantine-donepezil product by Allergan in the United States or (ii) the expiration of the Orange Book listed patents for which Allergan obtained rights from Adamas covering such product. However, Allergan's obligation to pay royalties for any product covered by the license is eliminated in any quarter where there is significant competition from generics.

Royalties recognized from Allergan are in the low double digits to mid-teens, as a percent of net sales of Namzaric in the United States. Based on recent trends of Namzaric sales, the tiered royalty is expected to be in the low double digits through the term of the agreement. Based on the current settlement agreements with the Namzaric Abbreviated New Drug Application (ANDA) filers to date, the earliest date on which any of these agreements grant a license to market a Namzaric ANDA filer's generic version of Namzaric is January 1, 2025 (or earlier in certain circumstances). Alternatively, the Namzaric ANDA filers with the earliest license date have the option to launch an authorized generic version of Namzaric beginning on January 1, 2026 instead of launching their own generic version of Namzaric on January 1, 2025.

Adamas expects that it will not receive royalties on sales of NAMENDA XR because of the entry of multiple generic versions of NAMENDA XR.

United Therapeutics

We have a license agreement with United Therapeutics Corporation for it to use one of our proprietary technologies in an oral formulation of treprostinil diethanolamine, or treprostinil, for the treatment of pulmonary arterial hypertension, and other indications. United Therapeutics Corporation launched Orenitram (treprostinil) in 2014, which triggered a $2.0 million milestone payment to the Company. In the third quarter of 2014, we received a cash payment of $30.0 million from HealthCare Royalty Partners III, L.P.'s (HC Royalty), for the purchase of certain of our rights under our license agreement with United Therapeutics Corporation related to the commercialization of Orenitram.This is a non-recourse liability for which we have no obligation to make any cash payments to HC Royalty, under any circumstances. Ownership of the royalty rights will return to us if/when a certain cumulative threshold payment to HC Royalty is reached.

We are entitled to receive milestones and royalties for the use of this formulation in indications other than arterial hypertension.

Takeda Pharmaceuticals Company Ltd.

The Company has entered into a licensing agreement with Takeda Pharmaceuticals Company Ltd. (Takeda) under which Takeda received the right to use the Company's intellectual property as a functional license. Microtrol, one of our key proprietary technology platforms, was utilized to develop Mydayis. The Company is eligible to receive royalties under this agreement based on net product sales of Takeda's product, Mydayis.

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Stendhal

The Company has entered into a collaboration agreement with Stendhal to commercialize both Oxtellar XR and Trokendi XR outside of the U.S. Those agreements include the right to use the Company’s intellectual property as a functional license, and generally include an up-front license fee and ongoing milestone payments upon the achievement of certain specific events. These agreements may also require minimum royalty payments, based on sales of products which use the applicable intellectual property.

Zydus Pharmaceuticals (USA), Inc.

The Company has settlement and licensing agreements dated in March 2017 and December 2022 with Zydus Pharmaceuticals (USA), Inc. (Zydus) (collectively, the "Zydus Agreements") to settle patent litigation and to grant Zydus with a non-exclusive license to market a generic version of Trokendi XR in the U.S. The Company is eligible to receive royalties under the Zydus Agreements based on net product sales and the number of generic equivalent products on the market in the U.S. Zydus launched its generic version of Trokendi XR in the first quarter of 2023.

Confidential Information and Inventions Assignment Agreements

We, including our subsidiaries, require our employees, temporary employees, and consultants to execute confidentiality agreements upon the commencement of employment, consulting, or collaborative relationships with us or our subsidiaries. These agreements provide that all confidential information developed by or made known during the course of the relationship with us or our subsidiaries be kept confidential and not disclosed to third parties, except in specific circumstances. The agreements provide that all inventions resulting from work performed for us or relating to our business and conceived of or completed by the individual during employment or assignment, as applicable, shall be our exclusive property or the exclusive property of the applicable subsidiary, in each case, to the extent permitted by applicable law.

We and our subsidiaries seek to protect our respective products, product candidates, and our technologies through a combination of patents, trade secrets, proprietary know-how, FDA exclusivity, and contractual restrictions on disclosure.

Government Regulation

U.S. Drug Development Process

The research and development process generally begins with discovery research, which focuses on the identification of a molecule that has the desired effect against a given disease. The FDA requires submission of an IND, which must become effective before human clinical trial testing may commence. The results of pre-clinical testing, along with other information, including information about product chemistry, product manufacturing and controls, and a proposed clinical trial protocol, are submitted to the FDA as part of the IND. Until the IND is approved or becomes effective following a waiting period, we may not start the clinical trials. This is typically followed by additional preclinical laboratory and animal testing, and adequate and well-controlled human clinical trials to establish the safety and efficacy of the proposed drug for its intended use. The satisfaction of FDA approval requirements typically takes many years. The actual time required may vary substantially based upon the type, complexity, and novelty of the product or disease.

Preclinical tests include laboratory evaluation, as well as animal studies to assess the characteristics and potential pharmacology, pharmacokinetics, and toxicity of the product. The conduct of the preclinical tests must comply with FDA regulations and requirements, including acceptable laboratory practices.

If preclinical testing of an identified compound proves successful, the compound moves into clinical development. While these are generally conducted in three sequential phases, the phases may overlap or be combined.

•Phase I - Involves the first human tests of the drug, in a small number of healthy volunteers or in patients (15 to 30 individuals), to assess safety, tolerability, potential dosing, and if possible, early evidence on effectiveness.

•Phase II - Involves trials in a relatively small group of patients (fewer than 100) to determine the effectiveness of the drug for a particular indication(s); dosage tolerance, and optimum dosage; and to identify common adverse effects and safety risks.

•Phase III - Involves tests confirming favorable results in earlier phases, in a significantly larger patient population, and to further demonstrate efficacy and safety. Phase III trials include both a control group that receives the standard treatment and a study group that receives the new treatment that is being tested.

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Clinical trials must be conducted in compliance with applicable regulations and consistent with acceptable clinical practices, as well as protocols detailing the objectives of the trial, the parameters to be used in monitoring safety, and the parameters to determine effectiveness. Each protocol involving testing on patients, and subsequent protocol amendments, must be submitted to the FDA as part of the IND. The FDA may order the temporary halt or permanent discontinuation of a clinical trial at any time, or to impose other sanctions if they believe that the clinical trial is not being conducted in accordance with the applicable requirements, or if continuing the trial presents an unacceptable risk to the clinical trial patients. The study protocol and informed consent information for patients in clinical trials must also be submitted to an institutional review board (IRB) or ethics committee for approval. The IRB/ethics committee may also require the clinical trial at the site to be halted, either temporarily or permanently, for failure to comply with the IRB/ethics committee requirements, or they may impose other sanctions.

Concurrent with clinical trials, companies usually complete additional animal studies and must develop additional information about the chemistry and physical characteristics of the product candidate. They must finalize a process for manufacturing the product in commercial quantities in accordance with current good manufacturing practice (cGMP) requirements. Moreover, the product used in late-stage clinical trials must be manufactured under the proposed commercial process and at the same scale as will be used commercially. The manufacturing process must be capable of consistently producing quality batches of the product candidate. The manufacturer must develop methods for testing the identity, strength, quality, and purity of the final product. Additionally, appropriate packaging must be selected and tested. Stability studies must be conducted to demonstrate that the product candidate does not undergo unacceptable deterioration over its shelf life under various conditions and for commercially viable lengths of time.

The research and development process, from discovery through a new drug launch, requires substantial time, effort, skill, and financial resources. The research and development of any product candidate has a significant amount of inherent uncertainty. Often, substantial resources must be committed even though success is far from assured. There is no guarantee when, or if, a product candidate will receive the regulatory approval required to launch a new drug or new indication of an existing drug.

In addition to the development of new products and new formulations, research and development projects also may include Phase IV trials, sometimes called post-marketing studies. For such projects, clinical trials are designed and conducted to collect additional data regarding, among other parameters, the benefits and risks of an approved drug. Alternatively, these trials may be conducted to assess the effectiveness of a product candidate in a new patient population.

U.S. FDA Review and Approval Processes

Drug development is an inherently uncertain process with a high risk of failure at every stage of development. After the completion of the required clinical testing, an NDA is prepared and submitted to the FDA. FDA approval of the NDA is required before marketing of the product may begin in the U.S. The NDA must include the results of all preclinical, clinical, and other testing, along with a description of the manufacturing process, validation of the manufacturing process, analytical tests conducted on the drug, proposed labeling, and other relevant information. The NDA requests approval to market the product. Each NDA is subject to a substantial user fee at the time of submission unless a waiver is granted by the FDA. A holder of an approved NDA may also be subject to annual product and establishment user fees. These fees typically increase annually.

The FDA has 60 days from its receipt of an NDA to determine whether the application will be accepted for filing, which is based on the agency's threshold determination that the NDA is sufficiently complete to permit substantive review. Additional information may be requested, rather than accepting an application for filing.

Once the submission is accepted for filing, the FDA begins an in-depth review. Review status could be either standard or priority. The review period for standard review applications is typically ten months and, for priority review applications, it is typically six months post acceptance. The review process may be extended by the FDA for three additional months to consider new information submitted during the review for clarification purposes.

The FDA may also refer applications for novel drug products or drug products that present difficult questions of safety or efficacy to an advisory committee, which is typically a panel that includes clinicians and other experts. The advisory committee reviews and evaluates information and prepares a recommendation as to whether the application should be approved. The FDA is not bound by the recommendation of an advisory committee, but it generally follows such recommendations. After the FDA evaluates the information provided in the NDA, it issues either an approval letter or a complete response letter. A complete response letter outlines the deficiencies in the submission and may require substantial additional testing or information in order for the FDA to reconsider the application. If and when those deficiencies have been addressed, the FDA will re-initiate review. If it is satisfied that the deficiencies have been addressed, the FDA will issue an approval letter.

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During the review period, the FDA will typically inspect one or more clinical sites to assure compliance with good clinical practice regulations. The FDA will inspect the facility(ies) at which the drug is manufactured to ensure compliance with cGMP regulations. The FDA may also undertake an audit of nonclinical and clinical sites. The FDA will not approve the product unless compliance is satisfactory and unless the application contains the data that provide substantial evidence that the drug is safe and effective in the indication studied.

A marketing approval authorizes commercial marketing of the drug, with specific prescribing information for specific indications. As a condition of NDA approval, the FDA may require a risk evaluation and mitigating strategy (REMS) to help ensure that the benefits of the drug outweigh the potential risks. REMS can include medication guides, communication plans for health care professionals, and elements to assure safe use, such as restricted distribution methods, patient registries, and other risk minimization tools. Moreover, as a condition to product approval, the FDA may require substantial post-marketing testing and surveillance to monitor the drug's safety or efficacy in commercial use and may impose other conditions, including distribution and labeling restrictions, which can materially affect the potential addressable market and profitability of the drug. Once granted, product approvals may be withdrawn if compliance with regulatory standards is not maintained, if problems are identified following initial marketing, or if post-marketing commitments are not met. Certain of the Company's commercial products have post-marketing commitments.

The approval process is lengthy and difficult. The FDA may refuse to approve the NDA if the applicable regulatory criteria are not satisfied. Further, data obtained from clinical trials are not always conclusive, or the FDA may interpret data differently than us. In addition, if a product receives regulatory approval, the approval may be significantly limited to specific diseases, dosages, or indications. This could restrict the commercial value of the product. Also, the FDA may require that certain contraindications, warnings, or precautions be included in the product labeling, as well as requiring Phase IV testing.

New Drug Application

Our activities encompass two types of NDAs: Section 505(b)(1) NDA (Full NDA) and Section 505(b)(2) NDA.

A Section 505(b)(1), which is a "full" or "stand-alone" NDA, must contain all pertinent information and full reports of investigations conducted by the applicant to demonstrate the safety and effectiveness of the drug, as well as complete preclinical, clinical, and manufacturing information.

Section 505(b)(2) NDAs often provide an alternative path to FDA approval for new or improved formulations or new uses of previously approved products. For a Section 505(b)(2) application, the FDA permits the submission of an NDA where at least some of the information required for approval comes from clinical trials not conducted by or for the applicant, and for which the applicant has not obtained a right of reference. The FDA permits the applicant to rely upon the FDA's previous findings of safety and effectiveness for an approved product. The FDA requires submission of information needed to support any changes to a previously approved drug, such as published data or new studies conducted by the applicant, including bioavailability or bioequivalence studies or clinical trials demonstrating safety and effectiveness. The FDA may then approve the new product candidate for all or some of the label indications for which the referenced product has been approved, as well as for any new indication sought by the Section 505(b)(2) applicant. The Section 505(b)(2) regulatory approval process is designed to allow for potentially expedited, lower cost and lower risk regulatory approval, based on previously established safety, efficacy, and manufacturing information on a drug which has been already approved by the FDA for the same or a different indication.

To the extent that the Section 505(b)(2) applicant is relying on studies conducted on previously approved drug product, the Section 505(b)(2) applicant must submit patent certifications with respect to any patents for the approved product on which the application relies that are listed in the FDA's publication, Approved Drug Products with Therapeutic Equivalence Evaluations, commonly referred to as the Orange Book. Specifically, the applicant must certify for each listed patent that either: (1) the required patent information has not been filed; or (2) the listed patent has expired; or (3) the listed patent has not expired but will expire on a particular date, and approval is not sought until after patent expiration; or (4) the listed patent is invalid, unenforceable or will not be infringed by the proposed new product. A certification that the new product will not infringe the previously approved product's listed patent or that such patent is invalid or unenforceable is known as a Paragraph IV certification.

If the applicant does not challenge one or more listed patents through a Paragraph IV certification, the FDA will not approve the Section 505(b)(2) NDA application until all the listed patents claiming the referenced product have expired. Further, the FDA also will not approve, as applicable, a Section 505(b)(2) NDA application until any non-patent exclusivity has expired, for example: five-year exclusivity period for obtaining approval of an NCE; or three year exclusivity period for an approval based on new clinical trials; or pediatric exclusivity, listed in the Orange Book for the referenced product.

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A section 505(b)(2) NDA applicant must send notice of the Paragraph IV certification to the owner of the referenced NDA for the previously approved product and relevant patent holders within 20 days after the Section 505(b)(2) NDA has been accepted for filing by the FDA. If the relevant patent holder elects to initiate litigation, the Section 505(b)(2) applicant may invest a significant amount of time and expense in the development of its product, only to be subject to significant delay and patent litigation before its product may be commercialized. Alternatively, if the NDA applicant or relevant patent holder does not file a patent infringement lawsuit within the specified 45 day period, the FDA may approve the Section 505(b)(2) application at any time.

Notwithstanding the approval of many products by the FDA pursuant to Section 505(b)(2) over the last few years, some pharmaceutical companies and others have objected to the FDA's interpretation of Section 505(b)(2). If the FDA changes its interpretation of Section 505(b)(2), or if the FDA's interpretation is successfully challenged in court, this could delay or even prevent the FDA from approving any Section 505(b)(2) NDA that we submit.

By its very nature, a Section 505(b)(1) NDA submission carries a higher degree of regulatory approval risk than a Section 505(b)(2) NDA submission. In addition, a requirement for more extensive testing and development can adversely impact our ability to compete with alternative products that arrive on the market sooner than our product candidate. Further, the time and financial resources required to obtain FDA approval could substantially and materially increase.

Review and Approval of Combination Products

Products comprised of separate components (e.g., a drug and a device; a biologic and a device; a drug and a biologic; or a drug, device, and a biologic) are known as "combination products." Such products often raise regulatory, policy, and review management challenges because they integrate components that are regulated under different types of regulatory requirements and by different FDA Centers, namely, Center for Drug Evaluation and Research (CDER), Center for Devices and Radiological Health (CDRH), and the Center for Biologics Evaluation and Research (CBER) (each a "Center"). Differences in regulatory pathways for each component can impact the regulatory processes for all aspects of product development and management, including preclinical testing, clinical investigation, marketing applications, manufacturing and quality control, adverse event reporting, promotion and advertising, user fees, and post-approval modifications.

The FDA's Office of Combination Products (OCP) determines which Center will have primary jurisdiction (the "Lead Center") for the combination product based on the combination product's "primary mode of action" (PMOA). A mode of action is the means by which a product achieves an intended therapeutic effect or action. The PMOA is the mode of action that provides the most important therapeutic action of the combination product or the mode of action expected to make the greatest contribution to the overall intended therapeutic effects of the combination product. The Lead Center has primary responsibility for the review and regulation of a combination product; however, a second Center is often involved in the review process, especially to provide input regarding the "secondary" component(s). In most instances, the Lead Center applies its usual regulatory pathway. For example, a drug-device combination product assigned to CDER will typically be reviewed under an NDA, while a drug-device combination product assigned to CDRH is typically reviewed through a 510(k), Premarket Approval Application (PMA), or de novo reclassification request.

Often it is difficult for OCP to determine with reasonable certainty the most important therapeutic action of the combination product. In those difficult cases, OCP will consider consistency with other combination products raising similar types of safety and effectiveness questions, or which Center has the most expertise to evaluate the most significant safety and effectiveness questions raised by the combination product. A sponsor may use a voluntary formal process, known as a Request for Designation, when the product classification is unclear or in dispute to obtain a binding decision as to which a product's primary mode of action as well as which center will regulate the combination product. If the sponsor objects to that decision, it may request that the agency reconsider that decision.

Combination products are subject to application User Fees based on the type of application submitted for the product's premarket approval or clearance. For example, a combination product for which an NDA is submitted is subject to the NDA fee under the Prescription Drug User Fee Act. Likewise, a combination product for which a PMA is submitted is subject to the PMA fee under the Medical Device User Fee and Modernization Act.

Since a combination product incorporates two or more components with different regulatory requirements, a combination product manufacturer must comply with all cGMP and Quality System (QS) Regulation/Medical Device Good Manufacturing Practices (QSR) requirements that apply to each component. The FDA has issued a combination product cGMP regulation, along with final guidance, describing two approaches a combination product manufacturer may follow to demonstrate compliance. Under these two options, the manufacturer demonstrates compliance with:

•All cGMP regulations applicable to each separate regulated component included in the combination product; or

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•Either the drug cGMPs or the QSR, as well as with specified provisions from the other of these two sets of requirements (also called the "streamlined approach”).

Pediatric Information

Under the Pediatric Research Equity Act of 2007 (PREA), NDAs or supplements to NDAs must contain data to assess the safety and effectiveness of the drug for the claimed indication(s) in all relevant pediatric subpopulations and to support dosing and administration for each pediatric subpopulation for which the drug is safe and effective. The intent of the PREA is to compel sponsors whose drugs have pediatric applicability to study those drugs in pediatric populations, rather than ignoring pediatric indications for adult indications that could be more economically desirable. The FDA may grant deferrals for submission of data, full waivers, or partial waivers of the data requirements. Unless otherwise required by regulation, PREA does not apply to any drug for an indication for which an orphan drug designation has been granted.

Orphan Drug Designation

Orphan drug designation is granted by the FDA to drugs intended to treat a rare disease or condition, which is generally a disease or condition that affects fewer than 200,000 individuals in the U.S., but there is no reasonable expectation that the cost of developing and making the product available in the U.S. for the disease or condition will be recovered from sales of the product. Orphan drug designation must be requested before submitting an NDA. Orphan drug designation does not convey any advantage or shorten the duration of the regulatory review and approval process. However, if an orphan drug later receives approval for the indication for which it has an orphan designation, the FDA may not approve any other applications to market the same drug for the same indication. Exceptions to this policy include showing clinical superiority to the product with the orphan drug exclusivity or if the license holder cannot supply sufficient quantities of the product. Orphan drug exclusivity in the U.S., which is seven years, does not prevent the FDA from approving a different drug for the same disease or condition, or the same drug for a different disease or condition, provided the sponsor has conducted appropriate clinical trials required for approval. Among the other benefits of an orphan drug designation, are tax credits for certain research expenses and waiver of the NDA application user fee for the orphan indication. However, a competitor obtaining orphan product exclusivity for a therapeutic agent before we do, could block the approval of one of our products for seven years for the same indication, unless we are able to demonstrate that our product is clinically superior, or the competitor cannot supply sufficient quantities of the product.

Priority Review

Under FDA policies, a drug candidate is eligible for priority review, or review within six months from filing, for a new molecular entity (NME). In addition, a six month review period may pertain to a non-NME if the drug candidate provides a significant improvement as compared to marketed drugs in the treatment, diagnosis, or prevention of disease. A fast track designated drug candidate would ordinarily meet the FDA's criteria for priority review. The FDA makes its determination of priority or standard review during the 60-day filing period post the initial NDA submission.

Fast Track Designation

The FDA is required to facilitate the development and expedite the review of drugs that are intended for the treatment of a serious or life-threatening condition and for which there is currently no effective treatment. These products must demonstrate the potential to address unmet medical needs for the condition. The FDA must determine if the drug candidate qualifies for the fast track designation within 60 days of receipt of the sponsor's request. Once the FDA designates a drug as a fast track candidate, it is required to facilitate the development and expedite the review of that drug by providing more frequent communication and guidance to the sponsor. In addition to other benefits such as greater interaction with the FDA, the FDA may initiate a review of the sections of a fast track drug's NDA before the application is complete. This rolling review is available if the applicant provides and the FDA approves a schedule for the submission of the remaining information, and if the applicant pays the applicable user fees. However, the FDA's review period for filing and reviewing an application does not begin until the last section of the NDA has been submitted. Additionally, a fast track designation may be withdrawn by the FDA, if the FDA believes that the designation is no longer supported by data emerging in the clinical trial process.

Post-Approval Regulatory Requirements

Any drugs for which we receive FDA approval are subject to continuing regulation by the FDA, including, among other things: record-keeping requirements; reporting of AE’s with the product; providing the FDA with updated safety and efficacy information; product sampling and distribution requirements; complying with certain electronic records and signature requirements; and complying with FDA promotion and advertising requirements.

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Drugs may be promoted only for the approved indication and in accordance with the provisions of the approved label. Changes to some of the conditions established in an approved application, including changes in indications, labeling, or manufacturing processes or facilities, may require submission for further review and approval by the FDA before the change can be implemented.

Adverse event reporting and submission of periodic reports is required following marketing approval. The FDA may also require post-marketing testing, known as Phase IV testing, REMS, and surveillance to monitor the effects of an approved product, or place conditions on an approval that could restrict the distribution and use of the product.

In addition, quality control, as well as the manufacture, packaging and labeling procedures must continue to conform to cGMPs after approval. Drug manufacturers and other entities involved in the manufacturing and distribution of approved drugs are subject to periodic unannounced inspections by the FDA and certain state agencies for compliance with cGMPs. Accordingly, manufacturers must continue to expend time, money, and effort in the areas of production and quality control to maintain compliance with cGMPs. Regulatory agencies may withdraw product approval, or request product recalls if a company fails to comply with regulatory standards, or if it encounters problems following initial marketing, or if previously unrecognized problems are subsequently discovered. In addition, prescription drug manufacturers in the U.S. must comply with applicable provisions of the Drug Supply Chain Security Act, provide and receive product tracing information; maintain appropriate licenses, ensure they only work and contract with other properly licensed entities, and have procedures in place to identify and properly handle suspect and illegitimate products.

Patent Term Restoration and Marketing Exclusivity

Depending upon the timing, duration, and specifics of FDA marketing approval of our product candidates, some of our U.S. patents may be eligible for limited PTE under the Hatch-Waxman Amendments. The Hatch-Waxman Amendments permit a patent term restoration of up to five years as compensation for patent term lost during product development and during the FDA regulatory review process. However, patent term restoration cannot extend the remaining term of a patent beyond a total of 14 years from the product's approval date. The patent term restoration period is generally 50% of the time between the effective date of an IND and the submission date of an NDA, plus the time between the submission date of an NDA and the approval of that application. Only one patent applicable to an approved drug is eligible for the extension, and the application for the extension must be submitted prior to the expiration of the patent and within sixty days of approval of the drug. The USPTO, in consultation with the FDA, reviews and approves the application for any patent term extension or restoration.

Market exclusivity provisions under the FDCA can also delay the submission or the approval of certain applications. The Federal Food, Drug, and Cosmetic Act (FDCA) provide a five-year period of non-patent marketing exclusivity within the U.S. to the first applicant to gain the approval of an NDA for an NCE. A drug is an NCE if the FDA has not previously approved any other new drug containing the same active pharmaceutical ingredient (API) or active moiety, which is the molecule or ion responsible for the therapeutic action of the drug substance. During the exclusivity period, the FDA may not accept for review an abbreviated new drug application (ANDA) or a Section 505(b)(2) NDA submitted by another company for another version of such drug, where the applicant does not own or have a legal right of reference to all the data required for approval. As an alternative to submission via 505(b)(2) approval, an applicant may choose to submit a full Section 505(b)(1) NDA, wherein the applicant would be required to conduct its own preclinical and adequate, well-controlled clinical trials to demonstrate safety and effectiveness. They may not refer to other clinical trials or data.

The FDCA also provides three years of marketing exclusivity for an NDA, Section 505(b)(2) NDA, or supplement to an existing NDA, if new clinical investigations (other than bioavailability studies) that were conducted or sponsored by the applicant are deemed by the FDA to be essential to the approval of the application. Such clinical trials may, for example, support: new indications; dosages; routes of administration; or strengths of an existing drug. Alternatively, these trials may be for a new use if the new clinical investigations conducted or sponsored by the applicant are determined by the FDA to be essential to the approval of the application. This exclusivity, sometimes referred to as clinical investigation exclusivity, prevents the FDA from approving an application under Section 505(b)(2) for the same conditions of use associated with the new clinical investigations before the expiration of three years from the date of approval. Such three-year exclusivity, however, would not prevent the approval of another application if the applicant submits a Section 505(b)(1) NDA and has conducted its own adequate, well-controlled clinical trials demonstrating safety and efficacy, nor would it prevent approval of a Section 505(b)(2) product that did not incorporate the exclusivity-protected changes of the approved drug product. The FDCA, FDA regulations, and other applicable regulations and policies provide incentives to manufacturers to create modified, non-infringing versions of a drug to facilitate the approval of an ANDA or other application for generic substitutes.

Pediatric exclusivity is a type of non-patent marketing exclusivity granted in the U.S. If granted, pediatric exclusivity, provides an additional six months of exclusivity to be attached to any existing exclusivity (e.g., three or five year exclusivity) or

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to patent protection for a drug. This six month exclusivity, which runs from the end of other exclusivity protection or patent delay, may be granted based on the voluntary completion of a pediatric trial in accordance with an FDA-issued "Written Request" for such a trial.

Other Regulatory Requirements

In March 2019, MDD US Operations, LLC (formerly US WorldMeds, LLC) and its subsidiary, Solstice Neurosciences, LLC (US) (collectively, the MDD Subsidiaries), each of which are now subsidiaries of the Company, entered into a Corporate Integrity Agreement (CIA) with the Office of Inspector General of the U.S. Department of Health and Human Services. Under the CIA, the MDD Subsidiaries agreed to pay $17.5 million to resolve U.S. Department of Justice allegations that the MDD Subsidiaries violated the False Claims Act by paying kickbacks to induce the use of APOKYN and MYOBLOC (collectively, the MDD Products). The fine was paid by the MDD Subsidiaries prior to the closing of the USWM Acquisition. The False Claims Act provides that any Person who knowingly submits false claims to the government is liable for treble damages as well as additional penalties.

As a consequence of the USWM Acquisition, and under the terms of the CIA, the Company has assumed the extensive obligations of the MDD Subsidiaries concerning the ongoing maintenance of an effective compliance and disclosure program to promote compliance with the statutes, regulations and written directives of Medicare, Medicaid and all other Federal health care programs and with the statutes, regulations and written directives of the FDA. The CIA has a term of five years, with the final Reporting Period ending in April 2024, and imposes material burdens on the Company, its officers and directors to take actions designed to insure compliance with applicable healthcare laws, including requirements to maintain specific compliance positions within the Company, to report any non-compliance with the terms of the agreement, to submit annual reports to the Office of Inspector General of the U.S. Department of Health and Human Services and to have prepared an annual audit by an Independent Review Organization. The CIA sets forth potentially substantial stipulated monetary penalties for non-compliance with the terms of the agreement. In addition, the Company may be excluded from participation in federally funded healthcare programs for a material breach of the CIA, which would result in substantial losses to the Company.

The U.S. has enacted a number of legislative and regulatory proposals to change the healthcare system in ways that could affect our ability to sell our products profitably. In the U.S., the Patient Protection and Affordable Care Act of 2010, as amended by the Health Care and Education Reconciliation Act of 2010 (as amended), is a sweeping measure intended to improve quality of care, constrain healthcare spending, and expand healthcare coverage within the U.S. This is accomplished primarily through the imposition of health insurance mandates on employers and individuals and the expansion of the Medicaid program.

In addition to FDA restrictions on the marketing of pharmaceutical products, several other types of state and federal laws have been applied to restrict certain business and marketing practices in the pharmaceutical industry in recent years. These laws include: anti-kickback; false claims; patient data privacy; civil monetary penalties statute; and security and transparency statutes and regulations.

The Federal Open Payments program requires certain manufacturers, including those that engage in the production, preparation, propagation, compounding, or conversion of drugs, devices, biological, and medical supplies for which payment is available under Medicare, Medicaid, or the Children's Health Insurance Program, with certain exceptions, to report annually to the federal government information related to payments and other transfers of value made to physicians (defined to include doctors, dentists, optometrists, podiatrists, and chiropractors) and teaching hospitals, as well as certain ownership and investment interests held by physicians and their immediate family members. Effective with the 2022 report filing, we are also required to report information regarding payments and other transfers of value provided during the previous year to physician assistants, nurse practitioners, clinical nurse specialists, certified nurse anesthetists and anesthesiologist assistants, and certified nurse-midwives.

The U.S. Foreign Corrupt Practices Act (FCPA), to which we are also subject, prohibits corporations and individuals from engaging in certain activities to obtain or retain business or influence a person working in an official capacity. Under FCPA, it is illegal to pay, offer to pay, or authorize the payment of anything of value to any foreign government official, government staff member, political party, or political candidate in an attempt to obtain or retain business or otherwise influence a person working in an official capacity. Historically, pharmaceutical companies have been the target of FCPA and other anti-corruption investigations and penalties.

In addition, we are subject to data privacy and security regulations by the federal government, the states, and certain foreign governments in which we conduct our business. The legislative and regulatory landscape for privacy and data protection continues to evolve, and there has been an increasing focus on privacy and data protection issues which may affect our business. Numerous federal and state laws and regulations, including state security breach notification laws, state health information privacy laws and federal and state consumer protection laws, govern the collection, use, disclosure, and protection of personal information. Failure to comply with such laws and regulations could result in government enforcement actions and create liability

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for us (including the imposition of significant penalties), private litigation and/or adverse publicity that negatively affects our business. In addition, healthcare providers who prescribe our products and research institutions we collaborate with are subject to privacy and security requirements under the Health Insurance Portability and Accountability Act of 1996 (HIPAA), as amended by the Health Information Technology for Economic and Clinical Health Act (HITECH). HIPAA and its implementing regulations impose certain requirements on covered entities, including certain healthcare providers, health plans, and healthcare clearinghouses as well as their respective business associates (including us) that create, receive, maintain or transmit individually identifiable health information for or on behalf of a covered entity and their subcontractors that use, disclose, access, or otherwise process individually identifiable protected health information, relating to the privacy, security and transmission of individually identifiable health information. Among other things, HITECH makes HIPAA's privacy and security standards directly applicable to business associates, which are independent contractors or agents of covered entities that receive or obtain protected health information in connection with providing a service on behalf of a covered entity. HITECH also created four new tiers of civil monetary penalties, amended HIPAA to make civil and criminal penalties directly applicable to business associates and possibly other persons, and gave state attorneys general new authority to file civil actions for damages or injunctions in federal courts to enforce the federal HIPAA laws and seek attorneys' fees and costs associated with pursuing federal civil actions. In addition, state laws govern the privacy and security of health information in certain circumstances, many of which differ from each other in significant ways and may not have the same effect, thus complicating compliance efforts.

In order to be eligible to have our products paid for with federal funds under the Medicaid and Medicare Part B programs and purchased by certain federal agencies and grantees, we must comply with the Veterans Health Care Act of 1992 (VHCA). The VHCA requires manufacturers to offer their covered drugs (biologics and single source and innovator multiple source drugs) for sale to certain federal agencies, including but not limited to, the Department of Veterans Affairs (VA), on a Federal Supply Schedule contract, at a price no higher than the statutory Federal Ceiling Price (FCP). The FCP is based on the non-federal average manufacturer price, or Non-FAMP, which we will have to calculate and report to the VA on a quarterly and annual basis. In addition, the Federal Supply Schedule contract requires compliance with applicable federal procurement laws.

Depending on the circumstances, failure to comply with these laws can result in penalties, including significant criminal, civil, and/or administrative criminal penalties, damages, fines, disgorgement, exclusion of products from reimbursement under government programs, "qui tam" actions brought by individual whistleblowers in the name of the government, imprisonment, additional reporting requirements and oversight if we become subject to a corporate integrity agreement or similar agreement to resolve allegations of non-compliance with these laws, refusal to allow us to enter into supply contracts, including government contracts, reputational harm, diminished profits, and future earnings, and the curtailment or restructuring of our operations, any of which could adversely affect our business.

In addition to regulations in the U.S., we are subject to a variety of foreign regulations governing clinical trials, commercial sales, as well as the distribution of our product candidates, to the extent we choose to clinically evaluate or sell products outside of the U.S. Whether or not we obtain FDA approval for a product, we must obtain approval of a product by the appropriate regulatory authorities of foreign countries before we can commence clinical trials or marketing of the product in those countries. The requirements, approval process and the time frame varies for each jurisdiction. As in the U.S., post-approval regulatory requirements, such as those regarding product manufacture, marketing, or distribution, would apply to any product that is approved outside the U.S. We generally market our products outside of the U.S. through licensing arrangements.

Refer to Part I, Item 1A—Risk Factors, for discussion of risks associated with government regulations.

Pharmaceutical Coverage, Pricing, and Reimbursement

Significant uncertainty exists as to the third-party payor coverage and reimbursement status of any of our products and product candidates for which we obtain regulatory approval. Sales of any products for which we receive regulatory approval for commercial sale will depend in part on the availability of reimbursement from third-party payors. Third-party payors include government health administrative authorities, managed care providers, private health insurers, and other entities. The process for determining whether a payor will provide coverage for a drug product may be separate from the process for setting the price or reimbursement rate that the payor will pay for the drug product. Third-party payors may limit coverage to specific drug products on an approved list, or formulary, which might not include all of the FDA-approved drug products for a particular indication. Third-party payors are increasingly challenging prices and examining the medical necessity and cost-effectiveness of medical products and services, in addition to their safety and efficacy. We may need to conduct expensive pharmaco-economic studies in order to demonstrate the medical necessity and cost-effectiveness of our products, in addition to the costs required to obtain the FDA approvals. Our product candidates may not be considered medically necessary or cost-effective by such third-party payors. A third-party payor's decision to provide coverage for a drug product does not imply that an adequate reimbursement rate will be approved. Adequate third-party reimbursement may not be available to enable us to maintain price levels sufficient to realize an appropriate return on our investment in product development.

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The Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act, collectively known as the Affordable Care Act (ACA), substantially changed the way healthcare is financed by both governmental and private insurers and significantly impacted the pharmaceutical industry. Federal, state, and local governments in the U.S. continue to consider legislation to limit the growth of health care costs, including the cost of prescription drugs. Future legislation could limit payments for pharmaceuticals, such as the product candidates that we are developing.

The marketability of any drug candidates for which we receive regulatory approval for commercial sale may suffer if the government and third-party payors fail to provide adequate coverage and reimbursement. In addition, emphasis on managed care in the United States has increased, and we expect will continue to increase the pressure on pharmaceutical drug pricing. Coverage policies and third-party reimbursement rates may change at any time. Even if favorable coverage and reimbursement status is attained for one or more products for which we receive regulatory approval, less favorable coverage policies and reimbursement rates may be implemented in the future.

Over the past several years an increasing number of U.S. states have passed, or are in the process of passing, new regulations designed to increase pricing transparency associated with pharmaceutical manufacturers. Many states have determined that it's in their preferred interest to take legislative action in order to curb drug price increases and to decrease their annual pharmaceutical spend. This momentum is likely to continue in the years ahead. Many of the enacted state price transparency regulations fall into the following categories: advance notice of price increases; price increase reporting; periodic price reports; new drug reporting; price information disclosures to Health Care Professionals and state agencies. The potential penalties for noncompliance vary by state regulation. While certain regulations do not contain specific penalty clauses most do and can contain penalties that can be significant per violation for noncompliance.

Environmental Matters

Our operations and those of our third-party manufacturers and suppliers are subject to national, state and local environmental laws. We have made, and intend to continue to make, expenditures and undertake efforts to comply with applicable laws. We believe the safety procedures utilized by us for the handling and disposing hazardous materials comply with the standards prescribed by applicable laws and regulations.

Human Capital

Our success begins and ends with our people. Our solid progress to date reflects the talent and hard work of all of our employees. We consider the intellectual capital of our employees to be an essential driver of our business and key to our future prospects. Attracting, developing, and retaining talented people in technical, marketing, sales, research, and other positions is crucial to executing our strategy and our ability to compete effectively. As of December 31, 2022, we employed 612 full-time employees in the U.S. None of our employees are represented by a labor union. We consider relations with our employees to be good.

Talent Acquisition, Retention and Development

Our key human capital objectives are to attract, retain and develop the highest quality talent. We employ various human resource programs in support of these objectives. Our ability to recruit and retain such talent depends on a number of factors, including compensation and benefits, talent development and career opportunities, and the work environment.

We attract and reward our employees by providing market competitive compensation and benefit packages, including incentives and recognition plans that extend to all levels in our organization. To that end, we offer a comprehensive total rewards program aimed at health, home-life, and financial needs of our employees. Our total rewards package includes market-competitive pay, broad-based stock grants, bonuses, healthcare benefits, retirement savings plans, paid time off and family leave, and an Employee Assistance Program, and mental health services.

We are committed to the safety, health, and security of our employees. We believe a hazard-free environment is critical for the success of our business. Throughout our operations, we strive to ensure that all our employees have access to safe workplaces that allow them to succeed in their jobs. Our experience and continuing focus on workplace safety has enabled us to preserve business continuity without sacrificing our commitment to keeping our colleagues and workplace visitors safe.

Inclusion and Diversity

We place a strong value on collaboration, inclusion, and diversity, and we believe that working together leads to better outcomes for our customers. This extends to the way we treat each other as team members. We strive to create an environment where innovative ideas can flourish by demonstrating respect for each other and valuing the diverse opinions, backgrounds, and

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viewpoints of employees. We believe a diverse and inclusive workplace results in business growth and encourages increased innovation, retention of talent, and a more engaged workforce.

In recent years we have been named to a number of best company lists, including the 2021 Forbes Best Small Companies list and the 2020 Best of Rockville – Pharmaceutical Companies list.

Other Information

We are listed on the NASDAQ Stock Exchange under the ticker symbol SUPN. Our principal executive offices are located at 9715 Key West Ave., Rockville, Maryland, 20850. Our website address is www.supernus.com.

We make available free of charge on our website our annual report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and any amendments to those reports, as well as proxy statements, and, from time to time, other documents, as soon as reasonably practicable after we electronically file such material with, or furnish such material to, the U.S. Securities and Exchange Commission (SEC). Through a link on the Investor Relations portion of our website, you can access our filings with the SEC. Information contained on our website is not a part of this Annual Report on Form 10-K.

The SEC also maintains a website at www.sec.gov that contains reports, proxy, and other information statements, and other information regarding issuers, including us, that file electronically with the SEC.

References to our website and the SEC’s website in this report are provided as a convenience and do not constitute, and should not be viewed as, incorporation by reference of the information contained on, or available through, such websites. Such information should not be considered a part of this report unless otherwise expressly incorporated by reference in this report.

ITEM 1A. RISK FACTORS.

Any investment in our business involves a high degree of risk. Before making an investment decision, you should carefully consider the risks described below, with all of the other information we include in this report and the additional information in the other reports we file with the Securities and Exchange Commission (the "SEC" or the "Commission"). These risks may result in material harm to our business, our financial condition, and the results of our operations. If a material, adverse event was to occur, the market price of our common stock may decline, and you could lose part or all of your investment.

RISK FACTORS SUMMARY

We are subject to a variety of risks and uncertainties, including risks related to our industry and business, risks related to our finances and capital requirements, risks related to securities markets and investment in our stock, and certain general risks, which could have a material adverse effect on our business, financial condition, results of operations and cash flows. The summary below is not exhaustive and is qualified by reference to the full set of risk factors set forth in this "Risk Factors” section.

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Risks Related to Our Industry and Business

• We are dependent on the commercial success of our products in the U.S. 29

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ITEM 1A. RISK FACTORS.

Risks Related to Our Finances and Capital Requirements

• Our operating results may fluctuate significantly. 55

Risks Related to Securities Markets and Investment in Our Stock

General Risk Factors

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ITEM 1A. RISK FACTORS.

Risks Related to Our Industry and Business

We are dependent on the commercial success of our products in the U.S.

Our financial performance, including our ability to replace revenue and income lost to generic products and other competitors as well as to grow our business, depends heavily on the commercial success of our products. A substantial amount of our resources are focused on generating, maintaining and/or expanding the revenue generated by our approved products in the U.S. If any of our major products, including, Oxtellar XR®, Qelbree®, GOCOVRI®, or APOKYN®, were to become subject to problems, such as changes in prescription growth rates, unexpected side effects, loss of intellectual property protection, supply chain or product supply shortages, regulatory proceedings, changes in labeling, publicity adversely affecting doctor or patient confidence in our product, material product liability litigation, pressure from new or existing competitive products, or adverse changes in coverage under managed care programs, the adverse impact on our revenue and profit could be significant. As noted in the "Business" section of this report, sales of a generic version of Trokendi XR® began in January 2023 and we expect those competitive products to significantly impact the sales of Trokendi XR and have an adverse impact on our revenue and profit. In addition, our revenue and profit could be significantly impacted by the timing and rate of commercial acceptance of key new products.

Our ability to generate significant product revenue from sales of our products in the near term will depend on, among other things, our ability to:

•Defend our patents, intellectual property, and products from the competition, both branded and generic;

•Maintain commercial manufacturing arrangements with third-party manufacturers;

•Produce, through a validated process, sufficiently large quantities of our products to meet demand;

•Continue to maintain a wide variety of internal sales, distribution, and marketing capabilities, sufficient to sustain and grow revenue;

•Continue to maintain and grow widespread acceptance of our products from physicians, health care payors, patients, pharmacists, and the medical community;

•Properly price and obtain adequate reimbursement coverage of these products by governmental authorities, private health insurers, managed care organizations, and other third-party payors;

•Maintain compliance with ongoing FDA labeling, packaging, storage, advertising, promotion, recordkeeping, safety, and other post-market requirements;

•Obtain approval from the FDA to expand the labeling of our approved products for additional indications;

•Adequately protect against and effectively respond to any claims by holders of patents and other IP rights alleging that our products infringe their rights; and

•Adequately protect against and effectively respond to any unanticipated adverse effects or unfavorable publicity that develops with respect to our products, as well as respond to the emergence of new or existing competitive products, which may be proven to be more clinically effective and cost-effective.

There are no guarantees that we will be successful in completing these tasks. We will need to continue investing substantial financial and management resources to maintain our commercial sales and marketing infrastructure and recruit and train qualified marketing, sales, and other personnel.

Sales of our products may slow for a variety of reasons, including competing products or safety issues. Any increase in sales of our products will be dependent on several factors, including our ability to educate physicians, to increase physician awareness, and physician acceptance of the benefits and cost-effectiveness of our products relative to competing products.

Our ability to increase market acceptance of any of our products or to gain market acceptance of approved product candidates among physicians, patients, health care payors, and the medical community will depend on a number of factors, including:

•Acceptable evidence of safety and efficacy;

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•Relative convenience and ease of administration;

•Prevalence, nature, and severity of any adverse side effects;

•Availability of alternative treatments, including branded and generic products; and

•Pricing and cost effectiveness.

Further, our products are subject to continual review by the FDA. We cannot provide assurance that newly discovered or reported safety issues would not arise. With the use of any marketed drug by a broader patient population, serious adverse events may occur from time to time that initially does not appear to be related to the drug itself. Any safety issues could cause us to suspend or to cease marketing of our approved products; cause us to modify how we market our approved products; subject us to substantial liabilities; and adversely affect our revenues and financial condition. In the event of a withdrawal of any of our products from the market, our revenues would decline significantly, and our business would be seriously harmed and could fail.

In addition, we have expressed certain long term revenue expectations. If we are not successful in broadening and/or maintaining the current commercial acceptance of our products, such that we cannot achieve those revenue expectations with respect to such products, this could result in a material adverse impact on our anticipated revenue, earnings, and liquidity.

If generics or other versions of extended or controlled release oxcarbazepine or topiramate, or other products including generics containing apomorphine hydrochloride, amantadine, or viloxazine hydrochloride, are approved and successfully commercialized, our business could be materially harmed.

Third parties have, and in the future may, receive approval to manufacture and market their own versions of extended release topiramate in the U.S. For example, Upsher-Smith launched Qudexy XR (extended release topiramate) and a branded generic version of Qudexy XR in 2014. Upsher Smith also entered into a settlement with two generic companies to launch a generic to Qudexy XR in 2020. In February 2021, one of the generic companies, Glenmark, entered the U.S. market with its own therapeutically equivalent generic products to Qudexy XR. The Company has entered into settlement agreements with third parties permitting the sale of a generic version of Trokendi XR on January 1, 2023. Sales of a generic version of Trokendi XR® began in January 2023. We have the right to defend our products against third parties who may infringe or are infringing our patents.

Third parties in the future may receive approval to manufacture and market their own versions of extended release oxcarbazepine or generics of Oxtellar XR in the U.S. In addition, we are aware of companies who are marketing modified-release oxcarbazepine products outside of the U.S., such as Apydan, which was developed by Desitin Arzneimittel GmbH and which requires twice-daily administration. If companies with modified-release oxcarbazepine products outside of the U.S. pursue or obtain approval of their products within the U.S., such competing products may limit the potential success of Oxtellar XR in the U.S. Our business and growth prospects could be materially impaired.

Accordingly, if any third party is successful in obtaining approval to manufacture and market a generic or its own version of extended release oxcarbazepine or topiramate in the U.S., we may not be able to prospectively realize revenues from Oxtellar XR or Trokendi XR.

In addition, third parties have, and in the future may, receive approval to manufacture and market their own products, including generics containing apomorphine hydrochloride for the treatment of Parkinson’s Disease in the U.S. For example, Acorda Therapeutics, Inc. launched Inbrija, an inhalable form of levodopa in 2019 and Sunovion Pharmaceuticals, Inc.'s (Sunovion, a subsidiary of Sumitomo Dainippon Pharma Co. Ltd) launched KYNMOBI, a sublingual film formulation of apomorphine hydrochloride, in 2020. In February 2022, the FDA approved the first generic of APOKYN (apomorphine hydrochloride injection) to treat hypomobility "off" episodes ("end-of-dose wearing off" and unpredictable "on/off" episodes) associated with advanced Parkinson's Disease. This approval is for an application of the drug cartridges only, which are compatible for use with the APOKYN pen, the brand-name pen injector. Patients treated with generic apomorphine hydrochloride will need to separately obtain the APOKYN pen. The success of these products and the entry of new products could adversely impact the sales of APOKYN.

Third parties in the future may receive approval to manufacture and market their own versions of viloxazine hydrochloride. Accordingly, if any third party is successful in obtaining approval to manufacture and market its own version of viloxazine hydrochloride, such competing products may limit the potential success of Qelbree in the U.S. Our business and growth prospects could be materially impaired.

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We are subject to uncertainty relating to payment or managed care reimbursement policies, which, if not favorable for our products or product candidates, could hinder or prevent our commercial success.

Our business is operating in an ever more challenging environment, with significant economic pressures exerted by federal and state governments, insurers, and private payors on the pricing of our products, affecting our ability to obtain and/or maintain satisfactory rates of reimbursement for our products. The U.S. federal and state governments and private payors are under intense pressure to control healthcare spending even more tightly than in the past. These pressures are further compounded by consolidation among distributors, retailers, private insurers, managed care organizations, and other private payors, resulting in an increase in their negotiating power, particularly with respect to our products. In addition, these pressures are intensified by increased, adverse publicity about pricing for pharmaceuticals. These prices are sometimes characterized as excessive, leading to government investigations and legal proceedings regarding pharmaceutical pricing practices.

Our ability, or our collaborators' ability, to successfully commercialize our products and product candidates, including Qelbree and SPN-830, will depend in part on the coverage and reimbursement levels set by governmental authorities, private health insurers, managed care organizations, and other third-party payors.

As a threshold for coverage and reimbursement, third-party payors require that drug products be approved for marketing by the FDA. Third-party payors are increasingly challenging the effectiveness of and prices charged for medical products and services. Government authorities and third-party payors have attempted to control costs, in some instances, by limiting coverage, by limiting the amount of reimbursement for particular medications, or by encouraging the use of lower-cost generic products.

We cannot be sure that reimbursement will be available for any of the products that we develop and, if reimbursement is available, the level of reimbursement. Moreover, that level of reimbursement may change over time as a result of requests from payors for higher levels of fees. Reduced or partial payment, or reduced reimbursement coverage, could make our products or product candidates less attractive to patients and prescribing physicians. We also may be required to sell our products or product candidates at a significant discount, which would adversely affect our ability to realize an appropriate return on our investment in our products or product candidates or to maintain profitability. Our business would also be adversely affected if private insurers, managed care organizations, the Medicare program, or other reimbursing bodies or payors limit the indications for which our products or product candidates will be reimbursed.

We expect that private insurers and managed care organizations will consider the efficacy, cost effectiveness, and safety of our products or product candidates in determining whether to approve reimbursement for such products or product candidates and to what extent they will provide reimbursement. Moreover, they will consider the efficacy and cost effectiveness of comparable or competitive products, including generic products, in making reimbursement decisions for our products. Because each third-party payor individually approves payment or reimbursement, obtaining these approvals can be a time consuming and expensive process, requiring us to provide scientific or clinical support for the use of each of our products or product candidates separately to each third-party payor. In some cases, it could take months or years before a particular private insurer or managed care organization reviews a particular product. Prior to that time, reimbursement may be negligible. We may ultimately be unsuccessful in obtaining coverage. In addition, our competitors may have more extensive existing business relationships with third-party payors that could adversely impact the coverage for our products.

Our business would be materially and adversely affected if we do not receive reimbursement for our products or product candidates from private insurers in a timely fashion or on a satisfactory basis. Our products and product candidates may not be considered cost-effective, and coverage and reimbursement may not be available or economically sufficient to allow us to sell our products or product candidates on a profitable basis.

In addition, many managed care organizations negotiate the reimbursement price of products through the use of formularies, which establish reimbursement levels. Exclusion of a product from a formulary can lead to sharply reduced usage in the managed care organization's patient population because reimbursement is limited and/or negligible. If our products are not included within an adequate number of managed care formularies or reimbursed at adequate levels, or if those policies increasingly favor generic products, our market share and gross margins could be negatively affected. This would have a material adverse effect on our overall business and financial condition.

There has been increasing legislative and enforcement interest in the U.S. with respect to specialty drug pricing practices. Specifically, there have been several recent U.S. Congressional inquiries and proposed federal and state legislative initiatives designed to, among other things, bring more transparency to drug pricing, reduce the cost of prescription drugs under the Medicare program, to review the relationship between pricing and manufacturer patient programs, and to reform government reimbursement methodologies for drugs. We expect to experience pricing pressures in connection with the sale of any of our products and product candidates due to the trend toward managed healthcare, the increasing influence of health maintenance organizations, additional cost containment initiatives, and additional legislative changes.

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In some foreign jurisdictions, particularly Canada and Europe, the pricing of prescription pharmaceuticals is subject to strict governmental control. In these countries, pricing negotiations with governmental authorities can take 6 to 12 months, or longer, after the receipt of regulatory approval and product launch. To obtain favorable reimbursement for the indications sought, or to obtain pricing approval in some countries, we may be required to conduct a clinical trial that compares the cost-effectiveness of our products or product candidates, if approved, to other available therapies. If reimbursement for our products or product candidates is unavailable in any country in which reimbursement is sought or is limited in scope or amount, or if pricing is set at unsatisfactory levels, our business could be materially harmed and unprofitable.

As evidenced by the passage of the American Rescue Plan Act of 2021 and the Inflation Reduction Act of 2022, discussed in greater detail below, we expect these challenges to continue and to potentially intensify in 2023 and following years, as political pressures mount, and healthcare payors, including government-controlled health authorities, insurance companies, and managed care organizations, step up initiatives to reduce the overall cost of healthcare, restrict access to higher-priced new medicines, increase the use of generic products and impose overall price cuts. Such pressures could have a material adverse impact on our business, financial condition, and results of operations.

We depend on wholesalers, distributors, and specialty pharmacies for the retail distribution of our products. If we lose any of our significant wholesaler, distributor, or specialty pharmacy accounts, our business could be harmed.

The majority of our product sales are to pharmaceutical wholesalers, specialty pharmacies, and distributors who, in turn, sell our products to pharmacies, hospitals, and other customers, including federal and state entities. The majority of sales of Oxtellar XR, Trokendi XR, XADAGO, and MYOBLOC are made to wholesalers and distributors. In addition, MYOBLOC is available for direct purchase by physicians and hospitals. The majority of sales of APOKYN, GOCOVRI, and Osmolex ER are made to specialty pharmacies.

The loss of any of these wholesale pharmaceutical distributors or wholesale and specialty pharmacy accounts, or a material reduction in their purchases, could have a material adverse effect on our business, results of operations, financial condition, and prospects. In addition, these wholesale customers comprise a significant part of the distribution network for pharmaceutical products in the U.S. This distribution network has undergone and may continue to undergo significant consolidation marked by mergers and acquisitions. As a result, a small number of large wholesale distributors control a significant share of the market.

Consolidation of drug wholesalers has increased. This may result in increased competition and pricing pressures on pharmaceutical products. We cannot assure you that we can manage these pricing pressures or that wholesaler purchases will not fluctuate unexpectedly from period to period.

Sales of our products can be greatly affected by the inventory levels that our respective wholesalers, specialty pharmacies, and distributors carry. We monitor wholesalers, specialty pharmacies, and distributor inventory of our products using a combination of methods. Pursuant to distribution service agreements with our three largest wholesale customers, we receive product inventory reports. For other wholesalers where we do not receive inventory reports, our estimates of wholesaler inventories may differ significantly from actual inventory levels. Significant differences between actual and estimated inventory levels may result in excessive stocking, resulting in our holding substantial quantities of unsold inventory, or, alternatively, inadequate supplies of product in the distribution channels. This could result in our inability to support sales at the retail level. These changes may cause our revenues to fluctuate significantly from quarter to quarter and, in some cases, may cause our operating results for a particular quarter to be below our expectations, the expectations of securities analysts, and/or the expectations of investors.

At times, wholesalers and distributors may increase inventory levels in response to anticipated price increases, resulting in both greater wholesaler purchases prior to the anticipated price increase and in reduced wholesaler purchases in later quarters. Accordingly, this may cause substantial fluctuations in our results of operations from period to period. If our financial results are below expectations for a particular period, the market price of our common stock may drop significantly.

We may not be able to effectively market and sell our product candidates, if approved, in the U.S.

We plan on building or expanding our sales and marketing capabilities in the U.S. to commercialize our product candidates if approved. This will require investing significant amounts of financial and management resources. If we are unable to establish and maintain adequate sales and marketing capabilities for our product candidates or do so in a timely manner, we may

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not be able to generate sufficient product revenues from our product candidates to be profitable. The cost of establishing and maintaining such marketing and sales capabilities may not be economically justifiable in light of the revenues generated by any of our product candidates. With the approval of Qelbree, our sales representatives who supported Trokendi XR and Oxtellar XR now devote their full efforts to the launch of Qelbree. This could have a detrimental impact on the future sales performance of Trokendi XR and Oxtellar XR.

Final marketing approval of any of our product candidates or approval of additional indications for existing products by the FDA or other regulatory authorities may be delayed, limited, or denied, any of which would adversely affect our ability to generate operating revenues.

We are dependent on obtaining regulatory approval of our product candidates and approval for additional indications for existing products. Our business depends on successful clinical development; i.e., successful completion of clinical trials and completion of requisite manufacturing information. We are not permitted to market any of our product candidates in the U.S. until we receive approval of an NDA from the FDA or market in any foreign jurisdiction until we receive approval from the requisite authority. Satisfaction of regulatory requirements typically takes many years, is dependent upon the type, complexity, and novelty of the product, and requires the expenditure of substantial resources. We cannot predict whether or when we will obtain regulatory approval to commercialize our product candidates. We cannot, therefore, predict the timing of any future revenues from these product candidates.

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