supn-20201231

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

FOR THE FISCAL YEAR ENDED December 31, 2020

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 52,923,107 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, 2020, 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 $1,205,174,821.

DOCUMENTS INCORPORATED BY REFERENCE

Certain portions of the registrant's definitive Proxy Statement for its 2021 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 2020 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, 2020

TABLE OF CONTENTS

Page

PART I

Item 1. Business 4

Item 1A. Risk Factors 26

Item 1B. Unresolved Staff Comments 65

Item 2. Properties 66

Item 3. Legal Proceedings 66

Item 4. Mine Safety Disclosures 66

PART II

Item 6. Selected Financial Data 69

Item 7A. Quantitative and Qualitative Disclosures about Market Risk 83

Item 8. Financial Statements and Supplementary Data 85

Item 9A. Controls and Procedures 132

Item 9B. Other Information 133

PART III

Item 10. Directors, Executive Officers and Corporate Governance 134

Item 11. Executive Compensation 134

Item 14. Principal Accounting Fees and Services 134

PART IV

Item 15. Exhibits, Financial Statement Schedules 135

SIGNATURES

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Unless the content requires otherwise, the words "Supernus," "we," "our" and "the Company" refer to Supernus Pharmaceuticals, Inc. and its subsidiaries

We 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®", “Xadago®”, “Myobloc®”, “Apokyn®”, "NeuroBloc®", 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 FDA concerning the New Drug Applications (NDA) for SPN-812 and SPN-830, the outcome of any additional device testing associated with the SPN-830 NDA submission, the potential approval of the NDAs for SPN-812, currently under review, and SPN-830 following resubmission, the planned submission to the FDA of a Supplemental New Drug Application for SPN-812 in adults, and the potential benefits and commercialization of SPN-812 and 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; completion of the purchase price allocation for the Company’s acquisition of USWM Enterprises, LLC; 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, hypomobility in Parkinson’s Disease (PD), cervical dystonia, and chronic sialorrhea. We are developing a broad range of novel CNS product candidates, including new potential treatments for attention-deficit hyperactivity disorder (ADHD), hypomobility in PD, epilepsy, depression, and rare 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 25 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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On April 21, 2020, we entered into a Development and Option Agreement (Development Agreement) with Navitor Pharmaceuticals, Inc. (Navitor). Under the terms of the Development Agreement, the Company and Navitor will jointly conduct a Phase II clinical program for NV-5138 (mTORC1 activator) (SPN-820) in treatment-resistant depression (TRD).

On April 28, 2020, we entered into a Sale and Purchase Agreement with US WorldMeds Partners, LLC to acquire the CNS portfolio of USWM Enterprises, LLC (USWM Enterprises) (USWM Acquisition). With the acquisition completed on June 9, 2020, we added three established commercial products, APOKYN, XADAGO, and MYOBLOC, and a product candidate in late-stage development, SPN-830 (apomorphine infusion pump), to our portfolio.

Our Strategy

Our vision is to become a leading biopharmaceutical company, 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. We will continue to drive the revenue growth of our commercial products by continuing to dedicate sales and marketing resources.

•Advance our current pipeline toward commercialization. We have a portfolio of early to late-stage product candidates. We continue to advance our late-stage product candidates, SPN-812 (viloxazine hydrochloride) for treatment of ADHD and SPN-830 (apomorphine infusion pump) for treatment of hypomobility in PD, to regulatory approval and commercialization.

•Target strategic business development opportunities. We are actively exploring a broad range of strategic opportunities that fit well with our strong presence in CNS. These include in-licensing products and entering into co-promotion partnerships, which are synergistic with our sales force call point for our commercial products and product candidates. We are also exploring co-development partnerships for our pipeline products and growth opportunities through value creation and transformative merger and acquisition transactions.

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

Commercial Products

The table below summarizes our portfolio of commercial products.

Trokendi XR

Trokendi XR is the first once-daily extended release topiramate product indicated for the treatment of epilepsy in the U.S. market. In 2013, we launched Trokendi XR for the treatment of epilepsy. In April 2017, we launched Trokendi XR for the prophylaxis of migraine headaches in adults and adolescents.

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Trokendi XR (topiramate) is indicated for: initial monotherapy in patients 6 years of age and older with partial onset or primary generalized tonic-clonic (PGTC) seizures; as add-on therapy in patients 6 years of age and older with partial onset or PGTC seizures or with seizures associated with Lennox-Gastaut Syndrome; and for prophylaxis of migraine headache in adults and adolescents 12 years of age and older. Trokendi 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. Trokendi XR's unique smooth pharmacokinetic profile results in lower peak plasma concentrations, higher trough plasma concentrations, and slower plasma uptake rates. This results in smoother and more consistent plasma concentrations than immediate release topiramate formulations. We believe that such a profile mitigates blood level fluctuations that are frequently associated with many side effects, thereby reducing the likelihood of breakthrough seizures or migraine headaches that patients can suffer when taking immediate release products. Side effects associated with immediate release products may lead patients to skip doses, which could place patients at higher risk for breakthrough seizures or migraine headaches.

Pursuant to the U.S. Food and Drug Administration's (FDA) approval of Trokendi XR, the FDA granted a deferral for submission of post-marketing pediatric studies in the following categories: (1) adjunctive therapy in partial onset seizures (POS) for children one month to less than six years of age; (2) initial monotherapy in POS and PGTC for children two years to less than ten years of age; and (3) adjunctive therapy in PGTC and adjunctive therapy in Lennox-Gastaut Syndrome for patients aged two years to less than six years of age.

Oxtellar XR

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 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.

Oxtellar XR (oxcarbazepine) is indicated as therapy of POS in adults and children 6 years to 17 years of age. With its novel pharmacokinetic profile showing lower peak plasma concentrations, a slower rate of plasma input, and smoother and more consistent blood levels as compared to immediate release products, we believe Oxtellar XR improves the tolerability of oxcarbazepine and thereby reduces side effects. In addition, Oxtellar XR once-per-day dosing is designed to improve patient adherence compared to the current immediate release products that must be taken multiple times per day.

Pursuant to the FDA's approval of Oxtellar XR, we committed to conducting four pediatric post-marketing studies; however, the FDA granted a waiver for the pediatric study requirements for ages from birth to one month, and a deferral for submission of post-marketing assessments for children one month to six years of age.

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. 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.

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.

In March 2017, XADAGO received FDA approval.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.

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MYOBLOC

MYOBLOC (rimabotulinumtoxinB) is a product indicated for the treatment of cervical dystonia and sialorrhea in adults, and it is the only Type B toxin available on the market. 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 of between 12-16 weeks. In sialorrhea, patients generally experienced symptom relief for up to three months post-dosing in well-controlled studies. In well controlled studies, injections of MYOBLOC have been shown to reduce the unstimulated salivary flow rate (USFR) by 0.3g/minute compared to placebo. MYOBLOC must be administered by a physician.

MYOBLOC was first approved by the FDA in 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. Pursuant to the FDA's approval of MYOBLOC for the treatment of chronic sialorrhea in adults, we will be conducting a clinical program under a Special Protocol Assessment from the FDA, which will address post-marketing commitments and potentially provide expanded indications for MYOBLOC.

We market rimabotulinumtoxinB in select European countries under the trade name NeuroBloc.In addition, our collaboration partner Eisai has been marketing rimabotulinumtoxinB in Japan since 2013 under the trade name NerBloc.

Research and Development

We are developing a pipeline of novel CNS product candidates for the treatment of various CNS conditions.The tablebelow summarizes our product candidates.

Product Candidate Indication Development NDA

SPN-812 Pediatric ADHD Under Review (1)

SPN-817 Severe Epilepsy Phase I

SPN-820 Depression Phase I

MYOBLOC Neurological Disorders Phase IV

(1) SPN-812 NDA was assigned a Prescription Drug User Fee Act (PDUFA) target action date in early April 2021.

(2) Assumes approval of the SPN-812 NDA.

(3) SPN-830 Refusal to File (RTF) letter received from FDA in November 2020.

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.

SPN-812 (extended release viloxazine hydrochloride)

SPN-812 is a novel non-stimulant product being developed for the treatment of ADHD in children and adults. It has a mechanism of action which can be described as multimodal. We believe SPN-812 could be well-differentiated compared to other non-stimulant treatments due to its different pharmacological and pharmacokinetic profile. The active ingredient in SPN-812, viloxazine hydrochloride, has an extensive safety record in Europe, where it was previously marketed for many years as an antidepressant, albeit at much higher dosage levels. Viloxazine hydrochloride will have a new chemical entity (NCE) status in the U.S.

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SPN-812 for the treatment of ADHD in pediatric patients

The Phase III pivotal program for SPN-812 for the treatment of ADHD in pediatric patients with ADHD consisted of four three-arm, placebo-controlled trials: P301 and P303 trials in patients 6 to 11 years old; and P302 and P304 trials in patients 12 to 17 years old. We announced positive topline results from the pediatric trials (P301 and P303) and the first adolescent trial (P302) in December 2018. Results of the second adolescent Phase III trial (P304) were released in March of 2019. Refer to the Company's Annual Report on Form 10-K for the year ended December 31, 2019, for the results of the previously completed Phase III trials in patients 6 to 11 years old and patients 12 to 17 years old.

In January 2020, the FDA accepted for review the NDA for SPN-812 for the treatment of ADHD in pediatric patients 6 to 17 years of age and assigned a Prescription Drug User Fee Act (PDUFA) target action date of November 8, 2020. In November 2020, the FDA issued a Complete Response Letter (CRL) regarding the NDA for SPN-812. The CRL indicated that the review cycle for the SPN-812 NDA was complete but was not ready for approval in its present form. The primary issue cited in the CRL relates to our in-house laboratory that conducts analytical testing, which recently moved to a new location. No clinical safety or efficacy issues were identified during the review.

In January 2021, we met with the FDA in a Type A meeting to discuss the CRL and the requirements for the NDA resubmission.In February 2021, we resubmitted the SPN-812 NDA and removed the reference to our in-house laboratory, and addressed other contents of the CRL.The FDA notified us that the NDA resubmission is a Class I resubmission with a PDUFA target action date in early April 2021.

We are preparing for the commercial launch of SPN-812 for the treatment of ADHD in pediatric patients, which is expected in the second quarter of 2021, if approved by the FDA.

SPN-812 for the treatment of ADHD in Adult patients

We initiated a Phase III program of SPN-812 for the treatment of ADHD in adult patients in the third quarter of 2019.

In December. 2020, we announced positive topline results from the P306 Phase III study of SPN-812 for the treatment of ADHD in adult patients. A total of 374 adult patients were randomized across placebo and a daily dose of SPN-812 starting with 200mg with flexible dose administration up to 600mg.At a daily dose of up to 600mg, the trial met the primary endpoint with statistical significance (p=0.0040) compared to placebo in improving the symptoms of ADHD from baseline to end of the study as measured by the Adult ADHD Investigator Rating Scale (AISRS).Patients receiving SPN-812 had a -15.5 point change from baseline in the primary endpoint compared to -11.7 for placebo at week 6 (p=0.0040).

In addition to meeting the primary efficacy endpoint, the Phase III study met the key secondary efficacy endpoint with statistical significance (p=0.0023) in the change from baseline of the Clinical Global Impression – Severity of Illness (CGI-S) Scale at week 6. The active dose was well tolerated. Patients who completed the study were offered the opportunity to continue into an ongoing open-label safety extension study.

At the end of the P306 study, SPN-812 reached statistical significance compared to placebo on the hyperactivity/impulsivity and inattention subscales of the AISRS with p-values of 0.0380 and 0.0015, respectively.

Assuming approval for SPN-812 for the treatment of ADHD in pediatric patients, we plan to submit a supplemental NDA (sNDA) to the FDA for SPN-812 for the treatment of ADHD in adult patients in the second half of 2021.

SPN-830 (Apomorphine Infusion Pump)

SPN-830 is a late-stage drug/device combination product candidate for the treatment of continuous prevention of “off” episodes in PD patients. 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 infusion may also limit some of the side effects of a subcutaneous injection of apomorphine.

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Results from the Phase III randomized Toledo study of SPN-830 for the continuous treatment of motor fluctuations (“on-off” episodes) in PD patients were published in The Lancet Neurology in 2018.The primary endpoint demonstrated that SPN-830 resulted in a 2.47 hours per day reduction in “off” time compared to placebo (0.58); p= 0.0025.Regina Katzenschlager et al. The Lancet Neurology. 2018;Vol 17(9):749-759.

In September 2020, we submitted an NDA to the FDA for SPN-830 for the continuous treatment of motor fluctuations (“on-off” episodes) in PD patients.In November 2020, we received a Refusal to File (RTF) letter from the FDA that stated the NDA was not sufficiently complete to permit a substantive review. In the RTF letter, the FDA requested certain documents and reports to be submitted in support of the application. We believe additional testing of the device will be necessary to support the SPN-830 NDA resubmission.

We have engaged in discussions with the FDA regarding the SPN-830 filing and expect to have ongoing future interactions with the FDA. We have scheduled a Type A meeting with the FDA in March 2021 to discuss the full contents of the RTF letter and clarify the steps required for the resubmission of the SPN-830 NDA. We plan to provide updates on the NDA status once we have agreed on the path forward for the program.

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 mechanism of action 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.

We plan on initially studying SPN-817 in severe epilepsy disorders. 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.

A pre-IND meeting with the FDA is planned for 2021 to enable a Dravet Syndrome Phase II study.

SPN-820 (NV-5138)

SPN-820 is a first-in-class, orally active small molecule that directly 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. This complex may be suppressed in people suffering from depression. 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 the novel MOA in depression may improve symptoms of depression in patients who have failed other agents.

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. Increased mTORC1 activity contributes to a broad array of aging diseases by increasing protein misfolding and driving cellular stress, inflammation, and fibrosis. 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.

Development activities are ongoing, including a multiple-ascending dose study in healthy volunteers, with the goal of initiating a Phase II clinical program in treatment-resistant depression by the end of 2021.

Market Overview

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.

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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. Extended release products may help patients improve adherence and, consequently, help patients enjoy a better quality of life.

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 recently 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. 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, and improved efficacy. Extended release products may help patients improve adherence, have fewer breakthrough migraines, and consequently, help patients enjoy a better quality of life.

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.

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.

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. For patients who experience significant "off" time each day, the Company has developed a product candidate as a continuous infusion pump (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.

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

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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.

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.

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.

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.

Migraine and Epilepsy Competition

Trokendi XR competes with all immediate release and extended release topiramate products, including Topamax, Qudexy XR, and their related generic products. For example, in February 2021, Glenmark Pharmaceuticals Limited (Glenmark) received final approval by the FDA for topiramate extended release capsules, the generic version ofQudexy XR capsules of Upsher-Smith Laboratories.

Trokendi XR also competes with other products used for the prevention of migraine headaches. Most notably, this includes anti-CGRPs (calcitonin gene related peptide), which is a new class of products introduced in 2018; Botox; beta-blockers; valproic acid; and amitriptyline.

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.

Parkinson’s Disease Competition

The most commonly prescribed medicine for PD is levodopa (L-dopa). 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.

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APOKYN is given as needed as an adjunct to levodopa/carbidopa therapy in PD patients who experience "off" episodes. It competes with all apomorphine hydrochloride products, including KYNMOBI. It also competes with other PRN therapies such as Inbrija, and other adjunctive therapies, including NOURIANZ.

XADAGO competes with other MAO-B inhibitors used to treat "off" episodes in PD, including rasagiline (AZILECT) and selegiline (Zelapar and EMSAM).

APOKYN and XADAGO also compete with other products for the treatment of PD, both branded and generic, including levodopa products.

Sialorrhea and Cervical Dystonia Competition

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.

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.

ADHD Competition

ADHD medications prescribed to both children and adults are broadly categorized as stimulants and non-stimulants. Stimulants for ADHD include amphetamine, methylphenidate, amphetamine, dexmethylphenidate, methylphenidate. Non-stimulant treatments for ADHD include atomoxetine, guanfacine, and clonidine.Stimulants and non-stimulants may be prescribed together for some ADHD patients.

Sales and Marketing

We market our products through our own sales force 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. As a result of the USWM Acquisition, we acquired an experienced commercial team, which includes a proven sales force and a medical organization with expertise and focus on serving movement disorder specialists and other specialized health care providers in the U.S. that will continue to commercially promote APOKYN, MYOBLOC, and XADAGO. We believe our current sales force of over 240 sales representatives is effectively targeting healthcare providers, primarily neurologists, to support and grow our current commercial products. Simultaneously promoting our neurology products allows us to leverage our commercial infrastructure and gain efficiencies in operations.

Assuming we obtain FDA approval for SPN-812, we anticipate expanding our existing sales force to market the commercial product to the relevant physician audience of psychiatrists, pediatricians, and primary care physicians.

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, 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 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 2020 and collectively accounted for more than 85% of our total product revenue in 2020.

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. We currently employ internal resources to manage our manufacturing contractors.

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We have entered into agreements with leading CMOs headquartered in North America, including Patheon Pharmaceuticals, Inc. (a subsidiary of Thermo Fisher Scientific Inc.), Packaging Coordinators, Inc, and Catalent Pharma Solutions, for the manufacture and packaging of the commercial products Oxtellar XR and Trokendi XR, as well as for our pipeline product candidate, SPN-812. These CMOs offer a comprehensive range of contract manufacturing and packaging services. Commercial products, as well as our product candidates, are single sourced from third-party suppliers.

APOKYN is manufactured for the U.S. market 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 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 €3.0 million. XADAGO is provided to us as a finished product by Zambon S.p.A. (Zambon).

Refer to Part I, Item 1A—Risk Factors for 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: Trokendi XR and Oxtellar XR; Adderall XR (developed for Shire); Intuniv (developed for Shire); Mydayis (developed for Shire); and Orenitram (developed for United Therapeutics Corporation); as well as our product candidate SPN-812.

We are also engaged in generating and assessing 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 through Investigational New Drug application (IND), enabling toxicology studies to support potential future clinical investigation.

Intellectual Property and Exclusivity

Overview

We continue to build our intellectual property portfolio to provide protection for our technologies, products, and product candidates. We 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 by, among other things, filing patent applications in the U.S. and abroad, including Europe, Canada, and other countries when appropriate. We also rely on trade secrets, know-how, proprietary knowledge, continuing technological innovation, and in-licensing opportunities to develop and maintain our proprietary position. We cannot be sure that patents will be granted with respect to any of our pending patent applications or with respect to any patent applications filed by us in the future, nor can we be sure that any of our existing patents or any patents that may be granted to us in the future will be commercially useful in protecting our technology or products. We cannot be sure that any patents, if granted, will sustain a legal challenge.

Patent Portfolio

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

Trokendi XR

We currently have ten U.S. patents that cover Trokendi XR. We own all of the issued patents. We have one patent issued for extended release topiramate in each of the following countries: Mexico; Australia; Japan; and Canada. We have two patents issued in Europe. 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 by January 1, 2023, or earlier under certain circumstances.

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Oxtellar XR

Our extended release oxcarbazepine patent portfolio currently includes twelve U.S. patents, nine of which cover Oxtellar XR. The nine 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 have two issued patents for extended release oxcarbazepine in both Europe and Australia and one patent issued in each of the following countries: Canada; Japan; China, and Mexico. In addition, we have a pending U.S. patent application that covers various extended release formulations containing oxcarbazepine.

The Company is currently in litigation with Apotex concerning Oxtellar XR. For more information, refer to Part I,

Item 3—Legal Proceedings in this annual Report on Form 10-K.

XADAGO

As an NCE, XADAGO is under the 5 year FDA exclusivity period that expires on March 21, 2022. The patent portfolio covering XADAGO has three U.S. patents licensed from Zambon. Two of these patents will expire no earlier than 2027, and one will expire no earlier than 2028.

SPN-812 (extended release viloxazine hydrochloride)

On SPN-812, we have three families of pending U.S. non-provisional and foreign counterpart patent applications for SPN-812. Patents, if issued, could expire from 2029 to 2033. We have one patent issued each in Europe and Canada, covering a method of treating ADHD using viloxazine hydrochloride. In another family, covering the novel synthesis process of the active ingredient, we have four patents issued in the U.S., five patents issued in Mexico, and one patent issued each in Europe, Japan, Canada, and Australia. We have four patents issued in the U.S. covering modified release formulations of viloxazine hydrochloride, two patents issued in Japan and Australia, and one patent issued in Mexico. We own all of the issued patents and the pending patent applications.

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. Additionally, we have filed patent applications in the U.S., Canada, Japan, China, Australia, Europe, and Mexico for various extended release formulations of huperzine A.

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

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.

SPN-830 (Apomorphine Infusion Pump)

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.

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

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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 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.

Other Intellectual Property Rights

We seek trademark protection in the U.S. and internationally, where available and when appropriate. We have filed for trademark protection for several marks, which we use in connection with our pharmaceutical research and development collaborations as well as with our products. We 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®", “XADAGO®”, “MYOBLOC®”, “APOKYN®”, "NeuroBloc®", and the registered Supernus Pharmaceuticals logo.

From time to time, we 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 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 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, 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 is subject to uncertainties that cannot be quantified in advance. In the event of an adverse outcome in litigation, we 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. In addition, litigation involving our patents carries the risk that one or more of our patents 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. In addition, third parties could allege that our products infringe their intellectual property rights and pursue legal action against the Company. See Part I, Item 1A—Risk Factors for risk factors related to intellectual property.

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Collaborations and Licensing Arrangements

We obtained exclusive licenses from third parties for proprietary rights to support our product candidates. Under these license agreements, we may be required to pay certain amounts upon the achievement of defined milestones. If these products are ultimately commercialized, we 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.

APOKYN and SPN-830 (Apomorphine Infusion Pump)

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 make royalty payments to Britannia 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. Based on this formula, the effective royalty rate is in the mid-thirties percent of U.S. net product sales. 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 in the Territory. 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. any product that competes with XADAGO. We are also required to spend certain annual amounts on educational, marketing, and promotional activities for XADAGO through 2022 and cooperate with Zambon concerning such activities.

Zambon is eligible to receive up to $30 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 high single digit 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 use, Perrigo is eligible to receive a $4 million future 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

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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, NeuroBloc 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 amounting to an estimated €3.0 million.

SPN-817 (huperzine A)

In September 2018, the Company 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. In addition, we may be obligated to pay up to $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. 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 milestone payments. We also will have the first right of refusal for any compound with a similar MOA on mTORC1 as NV-5138 in the central nervous system.

See Part II, Item 9, Financial Statements and Supplementary Data, Note 12, Investments in Unconsolidated VIEs, in the Notes to the Consolidated Financial Statements.

Rune HealthCare Limited

We have a purchase and sale agreement with Rune HealthCare Limited (Rune), where we obtained exclusive worldwide rights to a product concept from Rune for SPN-809. If we receive approval to market and sell any products covered by the agreement, we will be obligated to pay royalties on worldwide net product sales, at a rate in the low-single digits. There are no future milestone payments to Rune under this agreement.

United Therapeutics

We have a license agreement with United Therapeutics Corporation 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 million milestone payment to the Company. In the third quarter of 2014, we received a cash payment of $30 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

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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.

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.

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. The Company is eligible to receive royalties under this agreement based on net product sales of Takeda's product, Mydayis.

Confidential Information and Inventions Assignment Agreements

We require our employees, temporary employees, and consultants to execute confidentiality agreements upon the commencement of employment, consulting, or collaborative relationships with us. These agreements provide that all confidential information developed by or made known during the course of the relationship with us 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, to the extent permitted by applicable law.

We seek to protect our 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, to assess safety, tolerability, potential dosing, and if possible, early evidence on effectiveness.

•Phase II - Involves trials in a relatively small group of patients 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.

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•Phase III - Involves tests confirming favorable results in earlier phases, in a significantly larger patient population, and to further demonstrate efficacy and safety.

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.

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

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 healthcare professionals, and elements to assure safe use, such restricted distribution methods, patient registries, and other risk minimization tools. Moreover, product approval may require substantial post-approval 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.

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 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 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 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. 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.

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.

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 to further review and approval by the FDA before the change can be implemented.

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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 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 another type of exclusivity granted in the U.S. Pediatric exclusivity, if granted, provides an additional six months of exclusivity to be attached to any existing exclusivity (e.g., three or five year exclusivity) or 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.

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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 is 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 they 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.

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, ending in March 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 federally funded healthcare programs for a material breach of the CIA.

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; and security and transparency statutes and regulations.

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 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 from 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 1, Item 1A—Risk Factors, for discussion of risks associated with government regulations.

Pharmaceutical Coverage, Pricing, and Reimbursement

Significant uncertainty exists as to the 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 organizations. 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 the price 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. A payor’s decision to provide

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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.

In 2003, the U.S. government enacted legislation providing a partial prescription drug benefit for Medicare recipients, which became effective at the beginning of 2006. Government payment for some of the costs of prescription drugs may increase demand for any products for which we receive marketing approval. However, to obtain payments under this program, we would be required to sell products to Medicare recipients through prescription drug plans operating pursuant to this legislation. These plans will likely negotiate discounted prices for our products. Federal, state, and local governments in the U.S. continue to consider legislation to limit the growth of healthcare costs, including the cost of prescription drugs. Future legislation could limit payments for pharmaceuticals, such as the product candidates that we are developing.

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.

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.

Environmental Matters

We believe that our operations comply in all material respects with applicable laws and regulations concerning environmental protection.

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, 2020, we employed 563 full-time employees in the U.S. None of our employees is 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 practices, 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. Importantly during 2020, 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 during the COVID-19 pandemic.

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.

Investing in our common stock 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. In this eventuality, 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.

Risks Related to Our Industry and Business

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

•If other versions of extended or controlled release oxcarbazepine or topiramate, or other products including generics containing apomorphine hydrochloride for the treatment of Parkinson’s Disease, are approved and successfully commercialized, our business could be materially harmed.

•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.

•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.

•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.

•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 market.

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•If we do not obtain marketing exclusivity for our product candidates, our business may suffer.

•We depend on collaborators to work with us to develop, manufacture and commercialize their and our products and product candidates.

•We rely on and will continue to rely on outsourcing arrangements for certain of our critical activities, including clinical research of our product candidates, manufacture of our compounds and product candidates beyond Phase II clinical trials, and the manufacture of our commercial products.

•Delays or failures in the completion of clinical development of our product candidates would increase our costs, delay, or limit our ability to generate revenues.

•If we fail to comply with healthcare regulations, we could face substantial penalties. Our business, operations, and financial condition could be adversely affected.

•We could be involved in lawsuits to protect or enforce our patents, which could be expensive, time consuming, distracting, and ultimately unsuccessful.

•Limitations on our patent rights relating to our products and product candidates may limit our ability to prevent third parties from competing against us.

•The Company’s financial condition and results of operations for the fiscal year 2021 and beyond may be materially and adversely affected by the ongoing COVID-19 outbreak.

•Compliance with the terms and conditions of our Corporate Integrity Agreement requires significant resources and management time and, if we fail to comply, we could be subject to penalties or, under certain circumstances, excluded from government healthcare programs, which would materially adversely affect our business.

Risks Related to Our Finances and Capital Requirements

•We may identify material weaknesses in our internal controls over financial reporting or otherwise fail to maintain an effective system of internal controls, which might cause stockholders to lose confidence in our financial and other public reporting, which in turn would harm our business and the trading price of our common stock.

•We have and may further expand our business through acquisitions of new product lines or businesses, which exposes us to various risks, including difficulties in integrating acquisitions. Our recent acquisition poses certain incremental risks to the Company.

•Any impairment in the value of our intangible assets, including goodwill, would negatively affect our operating results and total capitalization.

Risks Related to Securities Markets and Investment in Our Stock

•The convertible note hedge transactions and the warrant transactions may affect the value of the notes and our common stock.

General Risk Factors

•Security breaches and other disruptions could compromise our information and expose us to liability, which would cause our business and reputation to suffer.

•Complying with increased financial reporting and securities laws reporting requirements has increased our costs and requires additional management resources. We may fail to meet these obligations.

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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.

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 maintaining and/or expanding the revenue generated by our approved products in the U.S. If any of our major products, Trokendi XR, Oxtellar XR, and 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. 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;

•Relative convenience and ease of administration;

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

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•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 other versions of extended or controlled release oxcarbazepine or topiramate, or other products including generics containing apomorphine 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 oxcarbazepine or 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 a generic company to launch a generic to Qudexy XR in 2020 and a separate settlement with Glenmark to enter the market at a date that is unknown to us. In February 2021, Glenmark entered the U.S. market with its own therapeutically equivalent generic products to Qudexy XR. The entry of new generic products could adversely impact the sales or prescriptions for Trokendi XR or could result in an earlier than anticipated entry of generics to compete with Trokendi XR. We have the right to defend our products against third parties who may infringe or are infringing our patents.

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 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 hydrocholoride, in 2020. The success of these products and the entry of new products could adversely impact the sales of prescriptions for APOKYN.

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 intense, 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 SPN-812 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.

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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, including Oxtellar XR, Trokendi XR, and APOKYN, 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.

We expect that private insurers and managed care organizations will consider the efficacy, cost effectiveness, and safety of our products or product candidates, including Oxtellar XR, Trokendi XR, and APOKYN, 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.

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.

Moreover, increasing efforts by governmental and third-party payors in the U.S. to cap or reduce healthcare costs may cause such organizations to limit both coverage and the level of reimbursement for newly approved products. As a result, they may not cover or provide adequate reimbursement for our products or product candidates.

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.

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.

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 or product candidates 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.

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We expect these challenges to continue and to potentially intensify in 2021 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, as well as on our reputation.

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 the sales of Oxtellar XR, Trokendi XR, XADAGO, and MYOBLOC are made to wholesalers and distributors who, in turn, sell our products to pharmacies, hospitals, and other customers. The majority of sales of APOKYN are made to specialty pharmacies, including Accredo Health Group, Inc. and Caremark LLC. For the year ended December 31, 2020, three wholesale pharmaceutical distributors, AmerisourceBergen Drug Corporation, Cardinal Health, Inc., and McKesson Corporation, each individually accounted for more than 25% of our total revenue from sales of our commercial products and collectively accounted for more than 85% of our total revenue from sales of these products in 2020. For the year ended December 31, 2020, the two specialty pharmacies, Accredo Health Group, Inc. and Caremark LLC, accounted for more than 35% individually and more than 80% collectively of the total revenue from sales of APOKYN.

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 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.

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

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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.

The FDA has substantial discretion in the drug approval process, including the ability to delay, limit or deny approval of a product candidate or deny a prior approval supplement(1) for many reasons. For example, the FDA

•Could reject or delay the marketing application for an NCE;

•Could determine that we cannot rely on Section 505(b)(2) for any approval of our product candidates;

•Could determine that the information provided by us was inadequate, contained clinical deficiencies, or otherwise failed to demonstrate the safety and effectiveness of any of our product candidates for a specific indication;

•May not find the data from bioequivalence studies and/or clinical trials sufficient to support the submission of an NDA or to obtain marketing approval in the U.S.;

•May find the clinical and other benefits of our product candidates do not outweigh their safety risks;

•May disagree with our trial design or our interpretation of data from preclinical studies, bioequivalence studies, and/or clinical trials, or may change the requirements for approval even after they have reviewed and commented on the design for our trials; the outcome and measurement scale used in the trials; or the clinical protocols whether with or without a special protocol assessment process;

•May determine that we have identified the wrong reference listed drug or drugs, or that approval of our Section 505(b)(2) application of our product candidate is blocked by patent or non-patent exclusivity of the reference listed drug or drugs;

•May identify deficiencies in the manufacturing processes or facilities of third-party manufacturers with which we enter into agreements for the supply of raw materials, including the active pharmaceutical ingredient (API) or formulated product used in our product candidates, wherein those deficiencies may result in an interruption in the ability to supply product;

•May approve our product candidates for fewer or more limited indications than we request, or may grant approval contingent on the performance of costly post-approval clinical trials;

•May change their approval policies or adopt new regulations;

•May not approve the labeling claims that we believe are necessary or desirable for the successful commercialization of our product candidates or may approve them with warnings and precautions that could limit the acceptance of our product candidates and their commercial success; or

•May not approve the addition of new indications to the label of our existing products.

(1) Changes that have a substantial potential to have an adverse effect on product quality, identity strength, purity, or potency (i.e., major changes) require submission of a "prior approval supplement" and approval by the FDA prior to distribution of the drug product made using the change.

Notwithstanding the approval of many products by the FDA pursuant to Sections 505(b)(1) and 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) application that we submit. Any failure to obtain regulatory approval of our product candidates would eliminate our ability to generate revenues for that candidate. Any failure to obtain such approval for all of the indications and labeling claims we deem desirable could reduce our potential revenues.

The process of obtaining regulatory clearances or approvals to market a medical device can be costly and time consuming. We may not be able to obtain these clearances or approvals on a timely basis, if at all. The FDA exercises significant discretion over the regulation of combination products, including drug and device components in a combination product.

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The FDA could in the future require additional regulation under the medical device provisions of the FDCA. We must comply with the QSR, which sets forth the FDA’s cGMP, requirements for medical devices, and other applicable government regulations and corresponding foreign standards for drug cGMPs. If we fail to comply with these regulations, it could have a material adverse effect on our business and financial condition.

In November 2020, we received a CRL from the FDA regarding the NDA for SPN-812. The FDA issued the CRL to indicate that the review cycle for the application was complete and that the application was not ready for approval in its present form. The FDA cited that the primary issue relates to our in-house laboratory that conducts analytical testing, which recently moved to a new location. In January 2021, we met with the FDA in a Type A meeting to discuss the CRL and the requirements for the NDA resubmission. In February 2021, we resubmitted the SPN-812 NDA and removed the reference to our in-house laboratory, and addressed other contents of the CRL. The FDA notified us that the NDA resubmission is a Class I resubmission with a PDUFA target action date in early April 2021.

After the expected approval for SPN-812 for one indication, additional indications may be submitted using the Section 505(b)(2) regulatory pathway. The FDA may not approve our filing under Section 505(b)(2) for SPN-812 for other indication(s), and therefore we would be required to submit a full NDA filing. In such a case, the time and financial resources required to obtain approval could also significantly increase.

In addition, we intend to complete the development of an infusion-pump delivery system containing apomorphine (SPN-830) and have submitted the NDA for SPN-830 to the FDA in September 2020. We received a refusal to file letter from the FDA and are seeking guidance from the FDA to clarify the steps required for the resubmission of the NDA for SPN-830. We are investing significant amounts of resources into the continued development of the infusion-pump delivery system. If we are unable to gain FDA approval for the infusion-pump delivery system or are unable to successfully commercialize the infusion-pump delivery system, we may not be able to generate revenue from the infusion-pump delivery system to justify the cost of invested company resources. In addition, as discussed further below, failure to gain FDA approval could have an adverse effect on the infusion-pump product’s commercial potential or could require additional costly studies.

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 market.

We do not currently own or operate manufacturing facilities for the commercial production of any of our products or our product candidates, nor do we have plans to develop our own manufacturing operations at a commercial scale in the foreseeable future. We currently depend on third-party CMOs in various countries for the supply of API for our products and product candidates, including drug substances for our preclinical research and clinical trials. For Trokendi XR, Oxtellar XR, MYOBLOC, XADAGO, and APOKYN, we currently rely on single source suppliers for raw materials, including API, as well as single source suppliers to produce and package final dosage forms.

There is a risk that supplies of our products or product candidates may be significantly delayed by or may become unavailable as a result of manufacturing, equipment, process, or business-related issues affecting our suppliers. Any future curtailment in the availability of raw materials or finished goods could result in production or other delays, with consequent adverse business effects. In addition, because regulatory authorities must generally approve raw material sources for pharmaceutical products, changes in raw material suppliers may result in production delays or higher raw material costs. For example, as it relates to SPN-812, we may encounter additional manufacturing and supply-chain risks due to the regulatory and political structure of Switzerland or as a result of the international relationship between Switzerland and the U.S. We may also encounter similar risks with the other products and product candidates where raw materials or finished goods are purchased from suppliers outside the U.S., such as the case for example for SPN-830 where the supplier for the infusion pump device is based in Italy and for APOKYN, XADAGO and MYOBLOC where the API manufacturer and finished goods supplier, respectively, are in Europe.

The manufacture of pharmaceutical products requires significant expertise and capital investment, including the development of advanced manufacturing techniques and process controls. Pharmaceutical companies often encounter difficulties in manufacturing, particularly in scaling up the production of their products. These problems can adversely affect production costs and yields, quality control, the stability of the product and quality assurance testing, as well as compliance with federal, state, and foreign regulations. If we are unable to demonstrate stability in accordance with commercial requirements, or if our manufacturers were to encounter difficulties or otherwise fail to comply with their obligations to us, our ability to obtain or maintain FDA approval and to market our products and product candidates, respectively, would be jeopardized. In addition, any delay or interruption in producing clinical trial supplies could delay or prohibit the completion of our clinical trials, increase the costs

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associated with conducting our clinical trials and, depending upon the period of delay, require us to commence new trials at the significant additional expense or to terminate a trial.

SUPN US Equity

SUPN · 10-K · period ended 2020-12-31

ITEM 1. BUSINESS.

ITEM 1A. RISK FACTORS.

SUPN US Equity☆

SUPN · 10-K · period ended 2020-12-31

ITEM 1. BUSINESS.

ITEM 1A. RISK FACTORS.

SUPN US Equity