SUPERNUS PHARMACEUTICALS, INC. (SUPN)

Item 2. Management's Discussion and Analysis of Financial Condition and Results of Operations

Management's Discussion and Analysis of Financial Condition and Results of Operations is intended to help the reader understand the results of operations and the financial condition of Supernus Pharmaceuticals, Inc. The interim condensed consolidated financial statements included in this report and this Management's Discussion and Analysis of Financial Condition and Results of Operations should be read in conjunction with our audited consolidated financial statements and notes thereto for the year ended December 31, 2025 and the related Management's Discussion and Analysis of Financial Condition and Results of Operations, both of which are contained in our Annual Report on Form 10-K, filed with the Securities and Exchange Commission on March 2, 2026.

In addition to historical information, this Quarterly Report on Form 10-Q contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, which are intended to be covered by the safe harbors created thereby. These forward-looking statements may include declarations regarding the Company's belief or current expectations of management, such as statements including the words "budgeted," "anticipate," "project," "forecast," "estimate," "expect," "may," "believe," "potential," and similar statements or expressions, which are intended to be among the statements that are forward-looking statements, as such statements reflect the reality of risk and uncertainty that is inherent in our business. Actual results may differ materially from those expressed or implied by such forward-looking statements. Readers are cautioned not to place undue reliance on these forward-looking statements, which are made as of the date this report was filed with the Securities and Exchange Commission. Our actual results and the timing of events could differ materially from those discussed in our forward-looking statements because of many factors, including those set forth under the "Risk Factors" section of our Annual Report on Form 10-K and elsewhere in this report as well as in other reports and documents we file with the Securities and Exchange Commission from time to time. Except as required by law, we undertake no obligation to update any forward-looking statements to reflect events or circumstances occurring after the date of this Quarterly Report on Form 10-Q.

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

Solely for convenience, in this Quarterly Report on Form 10-Q, the trade names are referred to without the TM symbols and the trademark registrations are referred to without the circled R, but such references should not be construed as any indicator that the Company will not assert, to the fullest extent under applicable law, our rights thereto.

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Overview

We are 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 attention-deficit hyperactivity disorder (ADHD), dyskinesia in Parkinson's Disease (PD) patients receiving levodopa-based therapy, hypomobility in PD, postpartum depression (PPD), epilepsy, migraine, cervical dystonia, and chronic sialorrhea. We are developing a broad range of novel product candidates for CNS disorders.

Merger of Equals with Indivior Pharmaceuticals

On August 1, 2026, the Company entered into an Agreement and Plan Of Merger (the "Merger Agreement"), by and among the Company, Indivior Pharmaceuticals, Inc., a Delaware corporation (Indivior), and Artemis Merger Sub Inc., a Delaware corporation and a wholly-owned subsidiary of Indivior (Merger Sub).

Pursuant to the Indivior Merger Agreement, and upon the terms and subject to the conditions thereof, Merger Sub will merge with and into the Company (the "Merger"), with the Company continuing as the surviving corporation and a wholly-owned subsidiary of Indivior. Following the completion of the Merger, the combined company will be renamed "Supernus, Inc." and its shares of common stock are expected to continue trading on the Nasdaq Stock Market under the ticker symbol "SUPN". The Merger and the other transactions contemplated by the Indivior Merger Agreement are referred to collectively as the "Transactions". The consummation of the Transactions is subject to various regulatory approvals and customary terms and conditions set forth in the Indivior Merger Agreement.

At the effective time of the Merger (the "Effective Time"), each share of common stock, par value $0.001 per share, of the Company (each, a "Company Share") issued and outstanding immediately prior to the Effective Time (other than certain excluded shares) will be converted into the right to receive 1.5401 shares of common stock, par value $0.001 per share, of Indivior (each, an Indivior Share and, such ratio, the Exchange Ratio, and the Indivior Shares issuable in the Merger, the Merger Consideration). Immediately prior to the Effective Time, stockholders of Indivior will receive a one-time special cash dividend of $1.0 billion. Indivior has secured a debt commitment of $650 million through a term loan facility, and the remaining portion will be funded by existing cash of the then-combined company. The Exchange Ratio is fixed and will not be adjusted for changes in the market price of either the Company Shares or the Indivior Shares.

Pursuant to the terms of the Merger Agreement, as of the Effective Time, (i) the board of directors of the Combined Company (the "Combined Company Board") will consist of eight individuals, including four individuals who are nominees of the board of directors of Indivior immediately prior to the Effective Time and four individuals who are nominees of the board of directors of Supernus immediately prior to the Effective Time; (ii) the Chair of the Combined Company Board will be a nominee of Indivior; (iii) Jack A. Khattar will serve as Chief Executive Officer and as a member of the Combined Company Board; and (iv) Timonthy C. Dec will serve as Chief Financial Officer.

Commercial Products

•Qelbree® (viloxazine) extended-release capsules is a novel non-stimulant product indicated for the treatment of ADHD in adults and pediatric patients 6 years and older. The United States Food and Drug Administration (FDA) approved Qelbree for the treatment of ADHD in pediatric patients 6 to 17 years of age in April 2021, and in adult patients in April 2022. The Company launched Qelbree for pediatric patients in May 2021 and for adult patients in May 2022 in the United States (U.S.). In January 2025, the FDA approved an expanded label update for Qelbree to include new data on the pharmacodynamics and use in breastfeeding mothers.

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

•ONAPGOTM (apomorphine hydrochloride) injection is the first and only subcutaneous apomorphine infusion device for the treatment of motor fluctuations in adults with advanced PD. ONAPGO was approved by the FDA in February 2025. ONAPGO was launched in April 2025.

•ZURZUVAE® (zuranolone) capsules is the first and only FDA approved oral medicine indicated for the treatment of PPD in adults. ZURZUVAE is a neuroactive steroid that is a positive allosteric modulator of GABAA receptors, targeting both synaptic and extrasynaptic GABAA receptors, and is the first oral, once-daily, 14-day treatment specifically indicated for adults with PPD. ZURZUVAE became commercially available in the U.S. in December 2023 as a treatment option for women with PPD. The Company and our collaboration partner, Biogen, are jointly commercializing

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ZURZUVAE in the U.S. under the Biogen Collaboration Agreement. The Company and Biogen equally share in all operating profits and losses arising from sales of ZURZUVAE in the U.S., with Biogen recording such product sales.

•APOKYN® (apomorphine hydrochloride injection) is a product indicated for the acute, intermittent treatment of hypomobility, "OFF" episodes ("end-of-dose wearing off" and unpredictable "ON/OFF" episodes) in patients with advanced PD.

•Trokendi XR® (topiramate) is the first once-daily extended-release topiramate product indicated for the treatment of epilepsy in patients 6 years of age and older in the U.S. market. It is also indicated for the prophylaxis of migraine headache in adults and adolescents 12 years and older.

•Oxtellar XR® (oxcarbazepine) is indicated as therapy for the treatment of partial onset seizures in patients 6 years of age and older. It is also the first once-daily extended-release oxcarbazepine product indicated for the treatment of epilepsy in the U.S. market.

•XADAGO® (safinamide) is a once-daily product indicated as adjunctive treatment to levodopa/carbidopa in patients with PD experiencing "OFF" episodes.

•MYOBLOC® (rimabotulinumtoxinB injection) is a product indicated for the treatment of cervical dystonia and chronic sialorrhea in adults. It is the only botulinum toxin type B available on the market.

Research and Development

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

SPN-817 (huperzine A)

SPN-817 represents a novel mechanism of action (MOA) for an anticonvulsant. SPN-817 is a novel synthetic form of huperzine A, whose MOA includes potent acetylcholinesterase inhibition, with pharmacological activities in CNS conditions such as epilepsy. The development will initially focus on the drug's anticonvulsant activity, which has been shown in preclinical models to be effective for the treatment of partial seizures and Dravet Syndrome. SPN-817 is in clinical development.

SPN-820 (NV-5138)

SPN-820 is a novel, first in class, intracellular enhancer of mechanistic target of rapamycin complex 1 (mTORC1) signaling. Depression is associated with synapse loss and reduced synaptic plasticity in key brain regions including the prefrontal cortex and increasing mTORC1-mediated synaptic plasticity is a promising avenue to treat depression and associated symptoms. SPN-820 selectively binds to intracellular sestrin proteins and subsequently engages a cascade of multi-protein complexes, enhancing mTORC1 signaling. The intracellular mechanism and the lack of binding to cell surface receptors suggests the potential for a differentiated safety profile and is unlikely to have abuse potential.

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In February 2025, the Company reported topline results from a randomized double-b

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ITEM 7.     MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS.

You should read the following discussion and analysis of our financial condition and results of operations together with our consolidated financial statements and related notes thereto, appearing elsewhere in this Annual Report on Form 10-K. In addition to historical information, some of the information in this discussion and analysis contains forward-looking statements reflecting our current expectations and involving risk and uncertainties. For example, statements regarding our expectations as to our plans and strategy for our business, future financial performance, expense levels, and liquidity sources are forward-looking statements. Our actual results and the timing of those events could differ materially from those discussed in our forward-looking statements because of many factors, including those set forth under the "Risk Factors" section and elsewhere in this report.

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

Overview

We are 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 attention-deficit hyperactivity disorder (ADHD), dyskinesia in Parkinson's Disease (PD) patients receiving levodopa-based therapy, hypomobility in PD, postpartum depression (PPD), epilepsy, migraine, cervical dystonia, and chronic sialorrhea. We are developing a broad range of novel CNS product candidates including new potential treatments for epilepsy, depression, and other CNS disorders.

2025 Acquisition of Sage Therapeutics, Inc. (Sage) and Reorganization

On July 31, 2025, the Company completed its previously announced acquisition of Sage when Saphire, Inc., a Delaware corporation and wholly owned subsidiary of the Company (Purchaser), was merged with and into Sage (the Merger), with Sage continuing as the surviving corporation in the Merger as a wholly owned subsidiary of the Company (the Sage Acquisition). At the time of the Sage Acquisition, Sage had an established commercial product in its portfolio, ZURZUVAE.

Following the Sage Acquisition, during the third quarter of 2025, Sage Therapeutics, Inc. was reorganized into Sage Therapeutics, LLC.

We have a portfolio of commercial products and product candidates.

Commercial Products

•Qelbree® (viloxazine) extended-release capsules are a novel non-stimulant product indicated for the treatment of ADHD in adults and pediatric patients 6 years and older. The United States Food and Drug Administration (FDA) approved Qelbree for the treatment of ADHD in pediatric patients 6 to 17 years of age in April 2021, and in adult patients in April 2022. The Company launched Qelbree for pediatric patients in May 2021 and for adult patients in May 2022 in the United States (U.S.). In January 2025, the FDA approved an expanded label update for Qelbree to include new data on the pharmacodynamics and use in breastfeeding mothers.

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

•ONAPGOTM (apomorphine hydrochloride) injection is the first and only subcutaneous apomorphine infusion device for the treatment of motor fluctuations in adults with advanced PD. ONAPGO was approved by the FDA in February 2025. ONAPGO was launched in April 2025.

•ZURZUVAE® (zuranolone) capsules are the first and only FDA approved oral medicine indicated for the treatment of PPD in adults. ZURZUVAE is a neuroactive steroid that is a positive allosteric modulator of GABAA receptors, targeting

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both synaptic and extrasynaptic GABAA receptors, and is the first oral, once-daily, 14-day treatment specifically indicated for adults with PPD. ZURZUVAE became commercially available in the U.S. in December 2023 as a treatment option for women with PPD. We and our collaboration partner, Biogen, are jointly commercializing ZURZUVAE in the U.S. under a collaboration agreement (Biogen Collaboration Agreement). The Company and Biogen equally share in all operating profits and losses arising from sales of ZURZUVAE in the U.S., with Biogen recording such product sales.

•APOKYN® (apomorphine hydrochloride injection) is a product indicated for the acute, intermittent treatment of hypomobility, "OFF" episodes ("end-of-dose wearing off" and unpredictable "ON/OFF" episodes) in patients with advanced PD.

•Trokendi XR® (topiramate) is the first once-daily extended-release topiramate product indicated for the treatment of epilepsy in patients 6 years of age and older in the U.S. market. It is also indicated for the prophylaxis of migraine headache in adults and adolescents 12 years and older.

•Oxtellar XR® (oxcarbazepine) is indicated as therapy for the treatment of partial onset seizures in patients 6 years of age and older. It is also the first once-daily extended-release oxcarbazepine product indicated for the treatment of epilepsy in the U.S. market.

•XADAGO® (safinamide) is a once-daily product indicated as adjunctive treatment to levodopa/carbidopa in patients with PD experiencing "OFF" episodes.

•MYOBLOC® (rimabotulinumtoxinB injection) is a product indicated for the treatment of cervical dystonia and chronic sialorrhea in adults. It is the only botulinum toxin type B available on the market.

Research and Development

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

SPN-817 (huperzine A)

SPN-817 represents a novel mechanism of action (MOA) for an anticonvulsant. SPN-817 is a novel synthetic form of huperzine A, whose MOA includes potent acetylcholinesterase inhibition, with pharmacological activities in CNS conditions such as epilepsy. The development will initially focus on the drug's anticonvulsant activity, which has been shown in preclinical models to be effective for the treatment of partial seizures and Dravet Syndrome. SPN-817 is in clinical development.

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SPN-820 (NV-5138)

SPN-820 is a novel, first in class, intracellular enhancer of mechanistic target of rapamycin complex 1 (mTORC1) signaling. Depression is associated with synapse loss and reduced synaptic plasticity in key brain regions including the prefrontal cortex and increasing mTORC1-mediated synaptic plasticity is a potential avenue to treat depression and associated symptoms. SPN-820 selectively binds to intracellular sestrin proteins and subsequently engages a cascade of multi-protein complexes, enhancing mTORC1 signaling. The intracellular mechanism and the lack of binding to cell surface receptors suggests the potential for a differentiated safety profile and is unlikely to have abuse potential.

In February 2025, the Company reported topline results from a randomized double-blind placebo-controlled Phase 2b study of SPN-820 in adults with treatment-resistant depression (TRD) following four weeks of chronic daily dosing. The study did not demonstrate a statistically significant improvement on the primary and secondary endpoints. The safety profile of SPN-820 was consistent with previous clinical trials, showing few adverse events.

The Company initiated a follow-on Phase 2b multi-center, randomized, double-blind, placebo-controlled trial in approximately 200 adults with MDD. The study will examine the safety and tolerability of SPN-820 2400 mg given intermittently (twice weekly) as an adjunctive treatment to the current baseline antidepressant therapy, as well as assess the rapid onset of improvement in depressive symptoms.

SPN-443 – Novel stimulant for the treatment of ADHD/CNS

The Company completed a Phase 1 single dose study in healthy adults in 2024 following submission of an Investigational New Drug Application. The study was a first in human, pilot pharmacokinetic study of two oral formulations of SPN-443 in healthy adults. The primary objective of the study was to assess safety and tolerability. This molecule, along with its major metabolites, is an inhibitor of norepinephrine, dopamine and serotonin, also known as a triple reuptake inhibitor. Both formulations of SPN-443 showed adequate bioavailability and were well tolerated. The Company plans to initiate Single Ascending Dose (SAD) and Multiple Ascending Dose (MAD) studies in the second half of 2026.

Zuranolone

The Company has granted Biogen sole rights to develop and commercialize zuranolone outside the U.S., other than in Japan, Taiwan and South Korea where it has granted those rights to Shionogi & Co., Ltd. (Shionogi). Shionogi is currently developing zuranolone for the treatment of patients with MDD in Japan, and in the third quarter of 2024, Shionogi reported that it submitted a new drug application (NDA) in Japan for zuranolone for the treatment of MDD. In the third quarter of 2025, Biogen received approval for zuranolone for the treatment of PPD by the European Medicines Agency (EMA) and Medicines Healthcare Regulatory Agency (MHRA) in Europe and the United Kingdom (U.K.) respectively. In the fourth quarter of 2025, zuranolone received Health Canada Authorization in Canada for treatment indicated for adults with PPD. Also in the fourth quarter of 2025, Shionogi received approval for a product containing zuranolone for the treatment of MDD by the Pharmaceuticals and Medical Devices Agency in Japan. No product containing zuranolone is approved for the treatment of MDD in the United States.

Product Pipeline Update

SPN-817 – Novel first-in-class highly selective AChE inhibitor for epilepsy

•The Phase 2b randomized, double-blind, placebo-controlled study of 3mg and 4mg twice daily doses is ongoing with a targeted enrollment of approximately 258 adult patients with treatment resistant focal seizures.

SPN-820 – Novel first-in-class molecule that increases mTORC1 mediated synaptic function for depression

•The Company initiated a follow-on Phase 2b multi-center, randomized, double-blind, placebo-controlled trial in approximately 200 adults with MDD. The study will examine the safety and tolerability of SPN-820 2400 mg given intermittently (twice weekly) as an adjunctive treatment to the current baseline antidepressant therapy, as well as assess the rapid onset of improvement in depressive symptoms.

SPN-443 – Novel stimulant for attention-deficit/hyperactivity disorder (ADHD)

•The Company expects to initiate a Phase 1 single-ascending/multiple-ascending dose study in adult healthy volunteers in the second half of 2026.

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Critical Accounting Policies and the Use of Estimates

The significant accounting policies and basis of presentation for our consolidated financial

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