SUPN US Equity☆

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 statements are described in Part II, Item 8—Financial Statements and Supplementary Data, Note 2, Summary of Significant Accounting Policies, in the Notes to the Consolidated Financial Statements. Our consolidated financial statements are prepared in accordance with U.S. generally accepted accounting principles (U.S. GAAP), requiring us to make estimates, judgments, and assumptions that affect the reported amounts of assets, liabilities, revenues, and expenses, and other related disclosures. Some judgments can be subjective and complex, and therefore, actual results could differ materially from those estimates under different assumptions or conditions.

We believe the judgments, estimates, and assumptions associated with the following critical accounting policies have the greatest potential impact on our consolidated financial statements:

•Revenue recognition;

•Business combination and valuation of acquired assets;

•Valuation of contingent consideration;

•Impairment of definite-lived intangible assets

Revenue Recognition

Our principal source of revenue is product sales. Revenue from product sales is recognized when physical control of our products is transferred to our customers, who are primarily pharmaceutical wholesalers, specialty pharmacies, and distributors. Product sales are recorded net of various forms of variable consideration, including: estimated rebates; sales discounts; and an estimated liability for future product returns (collectively, sales deductions).

The variability in the net transaction price for our products arises primarily from the aforementioned sales deductions. Significant judgment is required in estimating certain sales deductions, including rebates and returns. In making these estimates, we consider: historical experience; product price increases; current contractual arrangements under applicable payor programs; unbilled claims; processing time lags for claims; inventory levels in the wholesale, specialty pharmacy, and retail distribution channel; and product life cycle. We adjust our estimates at the earlier of when the most likely amount of consideration we expect to receive changes, or when the consideration becomes fixed. Variable consideration on product sales is only recognized when it is probable that a significant reversal will not occur. If actual results in the future vary from our estimates, we adjust our estimates in the period identified. These adjustments could materially affect net product sales and earnings in the period in which the adjustment(s) is recorded. Refer to Part II, Item 8—Financial Statements and Supplementary Data, Note 2, Summary of Significant Accounting Policies, in the Notes to the Consolidated Financial Statements, for further discussion on each of the different sales deductions. While sales rebates have been relatively predictable based on historical experience such that there have not been material changes in estimates in prior periods, there have been critical estimates associated with rebates and returns that may result in significant variability as further discussed below.

Returns

We maintain a return policy that allows our customers to return products within a specified period of time. Sales of our products are not subject to a general right of return; however, we will accept return of expired product 6 months prior to, and up to twelve months subsequent to, the product's expiry date for certain products. Our products have a shelf life of up to 48 months from date of manufacture. The product return accrual is estimated principally based on historical experience, the level and estimated shelf life of inventory in the distribution channel, changes in the current wholesaler prices, our return policy and expected market events, including generic competition. The time lag from date of sale of our products when we accrue our provision for product returns and the time at which we issue credit for expired product can occur up to several years after the sale of our product. Estimates associated with our provision for product returns are particularly susceptible to adjustment given the extensive time lag. The Company launched Qelbree in May 2021. The Company is actively monitoring returns activity in light of the timeline from the date of sale and the time at which we issue credit for expired products. We had favorable actual returns in 2024 and 2025 for Qelbree and as a result, the Company changed its estimated provision for Qelbree product returns based on the most recent experience. The Company has entered into settlement and license agreements with third parties, permitting the sale of a generic version of Trokendi XR beginning in January 2023. In addition, the Company entered into settlement and license agreements with third parties, permitting the sale of a generic version of Oxtellar XR beginning in September 2024. The Company is actively monitoring returns activity in light of the loss of exclusivity and actual and possible further future sales decline based on timing of generic entry. The entry of a generic competitor may cause our future Trokendi XR and Oxtellar XR product return rates to change from historical trends, and this change could have a material effect on the future provision for product returns.

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Historically, we have experienced changes in estimates in return reserve calculations, but those adjustments have not been material to net earnings (loss). Adjustments related to prior year sales for product returns in 2025 and 2024 was less than 4% of net product sales for each respective period and was less than 1% of net product sales in 2023. However, given the extensive number of inputs and assumptions, described above, future changes in our return reserves could be material.

Rebates

Rebates are discounts which we pay under either public sector or private sector health care programs. Rebates paid under public sector programs are generally mandated under law, whereas private sector rebates are generally contractually negotiated by us with managed care providers. Both types of rebates vary over time. Rebate amounts are typically based upon the volume of purchases using contractual or statutory prices, which may vary by product and by payer. For each type of rebate, the factors used in the calculations of the accruals for that rebate include the identification of the products subject to the rebate, applicable price terms and estimated lag time between sale and payment of the rebate, which can be significant. In order to establish the rebate accruals, we use both internal and external data to estimate the level of inventory in the distribution channel and the rebate claims processing lag time for each type of rebate. To estimate the rebate percentage or net price, we track sales by product and by customer or payer. We evaluate inventory data reported by wholesalers, available prescription volume information, product pricing, historical experience and other factors in order to determine the adequacy of our accruals. We regularly monitor our accruals and record adjustments when rebate trends, rebate programs and contract terms, legislative changes, or other significant events indicate that a change in reserve is appropriate. Historically, adjustments to rebate accruals have not been material to net earnings (loss).

Specifically, a significant portion of rebates we pay are on state Medicaid programs. We participate in state Medicaid programs wherein the lag time from the date of sale of our product when we accrue for provision for rebates and the ultimate invoicing by the individual state Medicaid program can occur up to several quarters after the sale of our product. Because of the time lag for Medicaid, in any particular quarter, our adjustments may incorporate revisions of accruals for prior periods. Estimates associated with our participation in state Medicaid programs are particularly susceptible to adjustment given the extensive time lag. Historically, adjustments to rebate accruals have not been material to net earnings (loss), but there continues to be an extensive time lag related to certain programs that could result in variability in future periods.

For a roll-forward of the accrued sales deductions, see the section entitled Results of Operations - Revenues - Sales deductions and related accruals.

Business Combinations and Valuation of Acquired Assets

The Company completed the Sage Acquisition on July 31, 2025. The transaction was accounted for as a business combination.

The acquisition method of accounting requires that we recognize the assets acquired and liabilities assumed at their acquisition date fair values. Goodwill is measured as the excess of consideration transferred over the acquisition date net fair values of the assets acquired and the liabilities assumed. The purchase price allocation is a critical accounting policy because the estimation of fair values of acquired assets and assumed liabilities is judgmental and requires various assumptions. Further, the amounts and useful lives assigned to depreciable and amortizable assets versus amounts assigned to goodwill, which is not amortized, can significantly affect the results of operations in the period of and for periods subsequent to a business combination.

Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction, and therefore represents an exit price. When identifiable intangible assets, are acquired, we determine the fair values of the assets as of the acquisition date. An income approach, which generally relies upon projected cash flow models, is used in estimating the fair value of the acquired intangible assets. These cash flow projections are based on management's estimates of economic and market conditions including: the estimated future cash flows from revenues of acquired assets; the timing and projection of costs and expenses, discount rates; and tax rates.

While we use our best estimates and assumptions as part of the process to value assets acquired and liabilities assumed at the acquisition date, our estimates are inherently uncertain and subject to refinement. During the measurement period, which occurs before finalization of the purchase price allocation, changes in assumptions and estimates that result in adjustments to the fair values of assets acquired and liabilities assumed, if based on facts and circumstances existing at the acquisition date, are recorded on a retroactive basis as of the acquisition date, with the corresponding offset to goodwill. Any adjustments not based on facts and circumstances existing at the acquisition date, or if subsequent to the conclusion of the measurement period, will be recorded to our consolidated statements of earnings.

Refer to Note 3, Sage Acquisition, for further information.

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Valuation of Contingent Consideration

We record contingent consideration resulting from a business combination at its fair value on the acquisition date. During the measurement period, if we obtain new information regarding facts and circumstances that existed as of the Sage Acquisition Closing Date that, if known, would have resulted in revised estimates of fair values of acquired assets, assumed liabilities or contingent consideration, the Company will accordingly revise its estimates of fair values and purchase price allocation. In addition, on a quarterly basis, we will revalue the contingent consideration liability and record increases or decreases in their fair value as an adjustment to operating earnings. The determination of the initial and subsequent value of the contingent consideration liability requires significant judgment by management. Changes in any of the inputs not related to facts and circumstances existing as of the acquisition date may result in a significant fair value adjustment, which can impact the results of operations in the period in which the adjustment is made.

As of December 31, 2025 and December 31, 2024 the Company reported contingent consideration liability of $31.3 million and $47.3 million, respectively, in its consolidated balance sheets related to the Sage Acquisition, USWM Acquisition, and Adamas Acquisition. There was no contingent consideration liability related to the USWM Acquisition and Adamas Acquisition as of December 31, 2025.

The Sage contingent consideration liability was $11.4 million as of the Sage acquisition date, and $31.3 million as of December 31, 2025. The contingent consideration is primarily associated with the fair value of the regulatory and commercial milestone and the sales-based milestones contingent consideration payments. The contingent consideration is related to one non-tradable contingent value right (CVR) which represents the contractual right to receive a contingent payment upon the achievement of the applicable regulatory and commercial milestone and sales-based milestones. The estimated fair value of the contingent consideration was determined using the Monte Carlo simulation. The key assumptions considered in estimating the fair value includes the estimated probability and timing of milestone achievement, such as the probability and timing of obtaining regulatory approval and first commercial sale in Japan, the estimated amount and timing of projected revenues, volatility, estimated discount rates and risk-free interest rate. The drug regulatory approval process is inherently uncertain, and any adverse action taken by the Pharmaceuticals and Medical Devices Agency in Japan can potentially impact our estimated fair value of the regulatory and commercial activities milestone. The possible outcomes for the contingent consideration range from $0 to $234 million on an undiscounted basis. Refer to Note 3, Sage Acquisition, and Note 7, Contingent Consideration, for further information. Subsequent to the Sage Acquisition, in December 2025, Shionogi, the Company's collaboration business partner, announced that it obtained manufacturing and marketing approval in Japan for ZURZUVAE® Capsules 30 mg for the indication of depression and depressive state. As a result, the Company's contingent consideration liability increased as of December 31, 2025.

Impairment of Definite-Lived Intangible Assets

Management assesses the potential impairment of our finite-lived intangibles whenever events or changes in circumstances indicate that the carrying value may not be recoverable. The carrying amount of the definite-lived intangible assets, net was $569.5 million as of December 31, 2025. Changes that could prompt such an assessment may include significant or adverse changes in the legal and regulatory environment, the introduction or advancement of competitive products and product candidates, changes in market demand, declining revenue and/or other events that indicate it is more likely than not that fair value is less than its carrying value. If a review of the definite-lived intangibles indicates that the carrying value of certain of these assets is more than the estimated undiscounted future cash flows, an impairment charge is made, as required, to adjust the carrying value to the estimated fair value. Evaluating for impairment requires judgment, including evaluating current economic and competitive circumstances, estimating future cash flows, future growth rates and future profitability. The primary inputs and assumptions used in the model included timing and projections of estimated future revenues and cash flows, loss of exclusivity, and discount rate. If the carrying amount of the asset exceeds its fair value, the Company writes down the asset to its estimated fair value, and an impairment loss equal to the difference between the assets fair value and carrying value is recognized in the consolidated statement of earnings (loss) in the period at which such determination is made. The use of different assumptions could increase or decrease the estimated fair value of assets and could therefore affect any impairment measurement. The Company recognized impairment charges of $20.2 million in 2023 mainly due to the partial write-off of the carrying value of some of its acquired intangible assets, primarily XADAGO. The primary factors that led to the impairment determinations were the following: (1) the performance of the commercial products; (2) forthcoming loss of exclusivity of XADAGO in December 2027, or earlier under certain circumstances, due to settlement agreements with third party generic companies; and (3) the change in the Company's future outlook of the brands.

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Results of Operations

In this section, we discuss the results of our operations for the year ended December 31, 2025, compared to the year ended December 31, 2024. Our Annual Report on Form 10-K for the year ended December 31, 2024, includes a discussion and analysis of our financial condition and results of operations for the year ended December 31, 2023, in Part II, Item 7—Management's Discussion and Analysis of Financial Condition and Results of Operations.

Revenues

Revenues consist primarily of net product sales of our commercial products in the U.S., supplemented by royalty and licensing revenues from our collaborative licensing arrangements. The following table provides information regarding our revenues during the years ended December 31, 2025 and 2024 (dollars in thousands):

Year Ended December 31, Change

Net product sales

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(1) Includes net product sales of MYOBLOC, XADAGO and Osmolex ER.

Net Product Sales

Net product sales decreased by $11.2 million from $637.7 million in 2024 to $626.5 million in 2025. The decrease was primarily due to the decline in net product sales of APOKYN due to lower volume, and decline in net product sales of Oxtellar XR and Trokendi XR due to generic erosion, partially offset by the increases in net product sales from Qelbree and GOCOVRI due to higher volume and higher price, and ONAPGO, which was launched in the second quarter of 2025.

On November 4, 2025, we announced that due to stronger than expected demand for ONAPGO, supplier constraints are impacting our ability to fully meet this demand. ONAPGO is manufactured in Europe, supplied to us by our ONAPGO licensing partner, and packaged in the U.S. by a third-party contract manufacturing organization. We currently rely on single source suppliers to produce and package final dosage forms for ONAPGO. On February 24, 2026, we announced that we have made progress in securing additional product supply of ONAPGO from the current supplier and as a result, has resumed new patient initiation. In addition, we are working with a second supplier that is expected to begin supplying ONAPGO in 2027. A change in any of the suppliers would require regulatory approval which could cause a further delay in manufacturing and a possible loss of sales, which could affect future operating results adversely.

Sales Deductions and Related Accruals

We record accrued product returns and accrued product rebates as current liabilities in Accrued product returns and rebates, on our consolidated balance sheets. We record sales discounts as a reduction against Accounts receivable, net on the consolidated balance sheets. Both amounts are generally affected by changes in gross product sales, changes in the provision for net product sales deductions, and the timing of payments/credits.

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The following table provides a summary of activities with respect to accrued product returns and rebates and sales discounts for the years ended December 31, 2025 and 2024 (dollars in thousands):

Accrued Product Returns and Rebates

ProductReturns ProductRebates Sales Discounts Total

Provision related to:

Provision related to:

Accrued Product Returns and Rebates

The accrued product returns balance decreased from $53.4 million as of December 31, 2024 to $37.8 million as of December 31, 2025. This decrease was primarily due to a decrease of $20.7 million of estimated provision for product returns related to prior year sales. The majority of the provision for product returns related to prior year sales is attributable to Qelbree, reflecting continued favorable actual returns experienced in 2025. As a result, the Company changed its estimated provision for product returns based on the most recent experience.

The accrued product rebates balance increased from $115.3 million as of December 31, 2024 to $123.3 million as of December 31, 2025 due to timing of payments associated with government programs.

Provision for Product Returns and Rebates

The provision for product returns decreased from $5.7 million in 2024 to $(10.2) million in 2025. The decrease was primarily due to the aforementioned $20.7 million of favorable adjustment in the estimated provision for product returns related to prior year sales.

The provision for product rebates increased from $387.8 million in 2024 to $432.8 million in 2025. The increase was primarily attributable to higher Qelbree sales and unfavorability in government programs as a result of product price increases in the first quarter of 2025.

Sales Discounts

The provision for sales discounts increased from $69.5 million in 2024 to $73.0 million in 2025 primarily attributable to new product launched in 2025 and higher Qelbree sales in 2025 compared to 2024.

Adjustments related to prior year sales

Adjustments related to prior year sales in 2025 of $21.1 million was approximately 4% of both net product sales and total provision for the year ended December 31, 2025. Adjustments related to prior year sales in 2024 of $14.0 million was less than 3% of both net product sales and total provision for the year ended December 31, 2024. As aforementioned, the majority of this adjustment is attributable to Qelbree, reflecting favorable actual returns experienced in 2025 and 2024.

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Collaboration Revenue (ZURZUVAE)

Collaboration revenue (ZURZUVAE) was $53.0 million for the year ended December 31, 2025. The increase was due to the Sage Acquisition in July 2025.

Royalty, Licensing and Other Revenues

Royalty, licensing and other revenues increased by $15.3 million from $24.1 million in 2024 to $39.4 million in 2025, primarily due to an increase in licensing revenues related to the achievement of a regulatory milestone under our collaboration agreement with Shionogi. The royalty term for Orenitram is expected to cease in 2027 which may result in a future decrease to royalty revenues.

Cost of Revenues

The following table provides information regarding our cost of revenues for the years indicated (dollars in thousands):

Year Ended December 31, Change

Cost of revenues includes the cost of royalties; cost of materials, including active pharmaceutical ingredients (API); and cost to manufacture, including tableting, packaging, personnel, overhead, stability testing, and distribution. Cost of revenues also includes our proportionate share of ZURZUVAE manufacturing costs under the Biogen Collaboration Agreement.

Cost of revenuesdecreased from $77.9 million in 2024 to $74.6 million in 2025. The decrease was primarily driven by lower APOKYN royalties due to lower sales and decrease in Oxtellar XR sales due to generic erosion, primarily offset by increases in cost of revenues from Qelbree due to higher sales, increase in cost of revenues from ONAPGO, which was launched in the second quarter of 2025, and increase in manufacturing costs related to ZURZUVAE under the Biogen Collaboration Agreement from the acquisition of Sage in July 2025.

Research and Development Expense

The following table provides information regarding ourResearch and development (R&D) expenses for the years indicated (dollars in thousands):

Year Ended December 31, Change

R&D expenses decreased from $108.8 million in 2024 to $106.2 million in 2025. The decrease was primarily due to decreased clinical program costs on SPN-820, partially offset by the increase in clinical program costs on SPN-817 and the Company's share of R&D expenses from the collaboration arrangement with Biogen. The Company acquired a collaboration agreement with Biogen as part of the acquisition of Sage in July 2025.

Selling, General, and Administrative Expense

The table below provides information regarding our Selling, general, and administrative (SG&A) expenses for the years indicated (dollars in thousands):

Year Ended December 31, Change

Selling and marketing expenses increased from $227.3 million in 2024 to $288.7 million in 2025. The increase was primarily due to higher professional and consulting expenses, higher employee-related expenses due to an increase in headcount because of the acquisition of Sage, higher marketing expense related to ONAPGO, which was launched in second quarter of 2025, and the Company's share of commercial expenses from the collaboration arrangement with Biogen in 2025.

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General and administrative expenses increased from $94.3 million in 2024 to $196.9 million in 2025. The increase was primarily due to the acquisition-related costs associated with the acquisition of Sage in July 2025. The one-time acquisition-related costs consist primarily of transaction costs of $10.0 million, post-combination employee-related expenses of $38.3 million, and post-combination share-based compensation expense of $25.0 million associated with the acceleration of the vesting of certain Sage's equity awards under the terms of the Merger Agreement and change in value of contingent value rights of the portion of potential CVR payments to former Sage employees which are considered probable under the employee compensation accounting model as of the fourth quarter of 2025.

Amortization of Intangible Assets

The following table provides information regarding the amortization expense for intangible assets during the periods indicated (dollars in thousands):

Year Ended December 31, Change

Amortization of intangible assets increased from $78.0 million in 2024 to $89.5 million in 2025. The increase is primarily due to ONAPGO and ZURZUVAE intangible assets amortization expense in 2025 offset by amortization expense in 2024 for Oxtellar XR and Namzaric intangible assets, which were fully amortized in 2024. Prior to the FDA approval of ONAPGO in February 2024, ONAPGO was previously accounted for as an indefinite-lived intangible asset not subject to amortization. ZURZUVAE intangible asset was acquired as part of the Sage Acquisition in July 2025.

Contingent Consideration Loss (Gain)

The following table provides information regarding the Contingent consideration loss (gain) during the periods indicated (dollars in thousands):

Year Ended December 31, Change

Contingent consideration was a loss of $25.4 million for the year ended December 31, 2025, and a gain of $6.1 million for the year ended December 31, 2024, respectively. The change was primarily due to an increase in fair value of the Sage contingent consideration associated with the regulatory and commercial milestone with the approval of ZURZUVAE for the treatment of MDD in Japan in December 2025, and the accretion of the USWM contingent consideration liabilities to the full milestone payment amounts with the approval of ONAPGO by the FDA in February 2025.

Other Income (Expense)

The following table provides the components of other income (expense) during the years indicated (dollars in thousands):

Year Ended December 31, Change

Interest and other income, net decreased to $13.3 million in 2025 from $16.2 million in 2024. The decrease was due to lower interest income on marketable securities largely driven by sale of marketable securities holdings of which the proceeds were used to partially fund the Sage Acquisition in July 2025.

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Income Tax Expense (Benefit)

The following table provides information regarding our income tax expense (benefit) during the periods indicated (dollars in thousands):

Year Ended December 31, Change

Effective tax rate 21 % 25 %

Income tax expense (benefit) was a benefit of $10.5 million and expense of $24.0 million for the years ended December 31, 2025 and December 31, 2024, respectively. The 2025 income tax benefit is primarily driven by pre-tax book loss as compared to prior year. The effective tax rate is impacted by the favorable effect of state taxes and the research and development credit, which is offset by the effect of expenses related to current and prior year transactions that are not deductible for tax purposes. Included within transaction costs are payments to former employees of Sage which are not deductible for tax purposes.

Net Earnings (Loss)

The following table provides information regarding our Net earnings (loss) during the periods indicated (dollars in thousands):

Year Ended December 31, Change

The decrease in Net earnings (loss) was primarily due to higher amortization of intangible assets, higher selling, general, and administrative expenses, and higher contingent consideration loss as a result of the acquisition of Sage in 2025, offset by higher revenues.

Financial Condition, Liquidity and Capital Resources

Summary of Cash Flows

The following table summarizes the major sources and uses of cash for the periods set forth below (dollars in thousands):

Year Ended December 31, Change

Net cash provided by (used in):

Operating Activities

Net cash provided by operating activitieswas $47.3 million in 2025 compared to $172.0 million in 2024. The decrease in cash flows provided by operating activities was primarily due to the decrease in net earnings for the year ended December 31, 2025 as well as changes in working capital. The Company reported a net loss of $38.6 million and net earnings of $73.9 million for the years ended December 31, 2025 and December 31, 2024, respectively. The decline in earnings is principally due to higher costs and expense in 2025 primarily due to the Sage Acquisition in July 2025. The Company recorded $72.9 million acquisition-related costs in 2025.

Investing Activities

Net cash provided by investing activities was $4.1 million in 2025 compared to $189.9 million used in investing activities in 2024. The change was primarily due to the following:

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•Net cash inflows from marketable securities activity were higher in 2025 compared to the same period in 2024 due to maturities of the marketable securities, whereby the proceeds were used to fund the Sage Acquisition in 2025 offset by

•Cash outflows related to the Sage Acquisition in 2025 (net of cash acquired) of $293.1 million.

Net cash used in investing activities in 2024 was primarily due to purchases of marketable securities, partially offset by higher cash inflows from the maturities of marketable securities.

Financing Activities

Net cash provided by financing activities was $9.1 million in 2025 compared to $12.2 million provided in the same period in 2024. The change was primarily due to the payment of the USWM contingent consideration milestones, offset by higher proceeds from the issuances of common stock in 2025 due to exercising of stock options.

Cash, Cash Equivalents, Marketable Securities, and Restricted Cash

Cash and cash equivalents, marketable securities, and restricted cashare comprised of the following (dollars in thousands):

Restricted cash 1,450 —

We have financed our operations primarily with cash generated from product sales, supplemented by revenues from royalty and licensing arrangements, as well as proceeds from the sale of equity and debt securities. Continued cash generation is highly dependent on the success of our commercial products, as well as the success of our product candidates if approved by the FDA. While we expect continued profitability in future years, we anticipate there may be significant variability from year to year in the level of our profits particularly due to continued market and payor pressures for our commercial products; the unfavorable impact of the loss of patent exclusivity for Trokendi XR in January 2023 and Oxtellar XR in September 2024; the potential unfavorable impact of the forthcoming loss of exclusivity of XADAGO; funding for research and development of our product candidates; the additional funding for the launch of ONAPGO, which was approved by the FDA in February 2025 and launched in April 2025, and the additional funding for the marketing of ZURZUVAE which was acquired as part of the Sage Acquisition in July 2025. Our marketable securities were lower in 2025 than during 2024 as a portion of the marketable securities we held were sold to fund the Sage Acquisition.

The Company believes its balances of cash, cash equivalents and unrestricted marketable securities, which totaled $308.7 million as of December 31, 2025, along with cash generated from ongoing operations and continued access to debt markets, will be sufficient to satisfy its cash requirements over the next twelve months and beyond.

We may, from time to time, consider raising additional capital through: new collaborative arrangements; strategic alliances; additional equity and/or debt financings; or financing from other sources, especially in conjunction with opportunistic business development initiatives. We will continue to actively manage our capital structure and to consider all financing opportunities that could strengthen our long-term financial profile. Any such capital raises may or may not be similar to transactions in which we have engaged in the past. There can be no assurance that any such financing opportunities will be available on acceptable terms, if at all.

Material Cash Requirements

Our material cash requirements include the following contractual and other obligations.

Leases

Our operating lease commitments include leases of fleet vehicles, leases of certain facilities, including the lease of the current headquarters office and laboratory space. As of December 31, 2025, we have fixed lease payment obligations of $47.0

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million, with $12.4 million payable within twelve months. Refer to Note 13, Leases in the Notes to the Consolidated Financial Statements in Part II, Item 8 of this report.

Manufacturing Purchase Obligations

In October 2021, we entered into an amendment to the Merz Agreement which increased the price of the annual purchase commitment of MYOBLOC from €3.0 million to approximately €3.9 million. An amendment to the contract manufacturing agreement with Merz was executed in July 2025. Amendments to the contract manufacturing agreement in July 2025 included, among other things, the removal of the annual minimum purchase requirement of MYOBLOC, and the Company's agreement to pay a nonrefundable annual fee of €3.0 million to cover general maintenance and reservation costs for the manufacturing facilities. For further discussion on the embedded operating lease related to the Merz Agreement, refer to Note 13, Leases in the Notes to the Consolidated Financial Statements in Part II, Item 8 of this report.

Milestone Payment Obligations from Acquisitions

As of December 31, 2025, no amounts are due from the contingent consideration milestone payable related to the Adamas Acquisition. As of December 31, 2024, there was one remaining outstanding milestone, Milestone 2025. Milestone 2025 (subject to certain terms and conditions and may only be achieved once) is payable upon the first occurrence of the achievement of aggregate worldwide net sales of GOCOVRI in excess of $225 million during any consecutive twelve-month period ending on or before December 31, 2025. At December 31, 2025, Milestone 2025 was not met in 2025 and therefore is no longer outstanding nor payable.

We also had contingent consideration milestones payable related to the USWM Acquisition. At December 31, 2024, there were two remaining outstanding milestones, one related to the approval of ONAPGO and the other related to the commercial launch of ONAPGO. Both milestones were met in 2025 and the liability was accreted to the milestone amounts due resulting in the recognition of $7.7 million change in fair value of contingent consideration during 2025. In February 2025, the Company paid the $25 million milestone related to the FDA's approval of ONAPGO in February 2025. ONAPGO was launched in April 2025 and the $30 million milestone payment related to the commercial launch of ONAPGO, subject to certain holdbacks as permitted under the Sale and Purchase Agreement Relating to USWM Enterprises, LLC, dated April 28, 2020, by and between US WorldMeds Partners, LLC and Supernus Pharmaceuticals, Inc., (USWM Sale and Purchase Agreement) became due and payable. Of the $30 million, the Company paid $2.3 million in the second quarter of 2025 and the remaining amount held was reclassified to Other current liabilities in the consolidated balance sheet as the milestone had been met but payment remains subject to certain holdbacks permitted under the USWM Sale and Purchase Agreement. The Company paid $1.9 million of the principal amount held back in the third quarter of 2025. The outstanding liability as of December 31, 2025 is $26.6 million, which included the principal amount held back and the interest. During the third quarter of 2025, USWorldsMeds Partners, LLC filed a complaint in the Superior Court of the State of Delaware seeking payment for the withheld amount, plus interest, attorney's fees and costs. See Part I Item 3 Legal Proceedings for further information on this matter.

The Company has contingent consideration milestones payable related to the Sage Acquisition. As of December 31, 2025, all milestone payments remain outstanding and payable upon achievement. Subject to the terms of the Sage CVR Agreement, $1.00 per share (equal to aggregate of $66.9 million) would be payable if in any calendar year between closing and end of 2027, annual net sales (as defined in the Sage CVR Agreement) of ZURZUVAE allocable to Supernus or any of its affiliates reach $250 million or more in the U.S., $1.00 per share (equal to aggregate of $66.9 million) would be payable if in any calendar year between closing and end of 2028, annual net sales (as defined in the Sage CVR Agreement) of ZURZUVAE allocable to Supernus or any of its affiliates reach $300 million or more in the U.S., (3) $1.00 per share (equal to aggregate of $66.9 million) would be payable if in any calendar year between closing and end of 2030, annual net sales (as defined in the Sage CVR Agreement) of ZURZUVAE allocable to Supernus or any of its affiliates reach $375 million or more in the U.S., and (4) $0.50 per share (equal to aggregate of $33.4 million) per share would be payable upon the first commercial sale in Japan to a third-party customer after regulatory approval for ZURZUVAE for the treatment of major depressive disorder (MDD) in Japan by June 30, 2026. As of December 31, 2025, the possible outcomes for the contingent consideration range, on an undiscounted basis, range from $0 to $234 million.

Further, with the Sage Acquisition in the third quarter of 2025, our investment balance decreased as marketable securities were sold to fund the acquisition of Sage. Refer to Part II, Item 7 - Management's Discussion and Analysis of Financial Condition and Results of Operations and Management's discussion on Financial Condition, Liquidity and Capital Resources of this Annual Report on Form 10-K for the period ended December 31, 2025, and Note 1, Business Organization, in the Notes to the Consolidated Financial Statements in Part II, Item 8 of this Annual Report.

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In January 2026, the Company entered into an agreement with former Biscayne security holders wherein the Company will pay $10.0 million on June 30, 2026 for settlement of certain developmental milestones under the merger agreement entered into in 2018.

Biogen Collaboration Obligations

Pursuant to the Biogen Collaboration Agreement, we are jointly commercializing ZURZUVAE in the United States with Biogen. We have a contractual obligation to share equally in all operating profits and losses arising from the sales of ZURZUVAE in the U.S. Consequently, we are required to fund 50% of the development and commercialization expenses incurred for the U.S. market, including 50% of the costs associated with non-discretionary FDA post-marketing requirements, such as required studies in adolescent populations. To the extent that shared commercialization and development expenses exceed net revenues in any given period, we are obligated to make cash payments to fund our share of the operating loss.

While Biogen records net product sales for ZURZUVAE in the U.S., the collaboration necessitates a periodic reconciliation process to ensure the equal sharing of economics, which results in net expense reimbursement payments between the parties. We may incur obligations to reimburse Biogen for our share of selling, general, and administrative expenses, and research and development expenses, in each case, when Biogen’s incurred costs exceed ours.

We are also currently responsible for the manufacturing supply chain for the collaboration. This requires us to finance the costs of manufacturing active pharmaceutical ingredients (API) and bulk drug product for commercialization in territories outside of the United States other than Japan, the Republic of Korea and Taiwan (the Biogen Territory). While Biogen is obligated to reimburse us for the costs of supply related to marketing and sales in the Biogen Territory, we are required to fund the initial cash payments to third-party contract manufacturing organizations prior to receiving reimbursement from Biogen. These manufacturing activities result in working capital requirements that fluctuate based, in part, on Biogen’s long-term demand forecasts for sales in the Biogen Territory and will continue until such time as Biogen assumes manufacturing responsibilities for the Biogen Territory as permitted under the agreement.

Navitor Development Agreement

We have obligations from the Development Agreement with Navitor Inc. we entered into in April 2020. The Company can terminate the Development Agreement upon 30 days' notice. Under the terms of the Development Agreement, the Company and Navitor Inc. will jointly conduct a Phase 2 clinical program for NV-5138 (SPN-820) for treatment-resistant depression. The Company will bear all of Phase 1 and Phase 2 development costs incurred by either party, up to a maximum of $50 million. There are certain additional payments which could be incurred by the Company that are contingent upon Navitor Inc. achieving defined milestones. These milestone payments include 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. The Company has an option to acquire or license NV-5138 (SPN-820), for which additional payments would be required. In the second quarter of 2024, the Company consented to payment of additional Phase II development costs for NV-5138 (SPN-820) as they are incurred, but reserves the right to terminate payment of future development costs at its discretion. On May 5, 2025, the Company entered into a binding memorandum of understanding (MOU) with Navitor Inc. Under the MOU, the Company agreed to conduct further development activities at its own cost and Navitor Inc. agreed to waive its right to receive the $100 million Initial Acquisition Fee under the Development Agreement. In addition, pursuant to the MOU the Company exercised the Purchase Option to purchase all assets of Navitor and its affiliates pursuant to the Development Agreement, subject to, among other things, completion of satisfactory due diligence by the Company, and negotiation and execution of a definitive Purchase Agreement. On June 24, 2025, October 31, 2025 and December 22, 2025, the Company amended the MOU with Navitor to extend the negotiation period.

Royalty Payments

We obtained exclusive licenses from third parties for proprietary rights to support our commercial products and product candidates. We are obligated to pay royalties to third parties, computed as a percentage of net product sales, for each respective product under a license agreement, beginning upon commercialization. The amount of future royalty obligations are dependent on future net product sales of each of the respective products under a license agreement.

Other Obligations

We have other obligations in which the timing, likelihood and, in some situations, the amount of such payments are not known, which include the following:

•any milestone payments which may become payable to third parties under license agreements or contractual agreements regarding our clinical trials, or those which may become payable upon achieving sales, regulatory, and developmental milestones

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per contractual agreements.

•liabilities related to uncertain tax positions. Due to uncertainties in the timing of potential tax audits, the timing and the amounts associated with the resolution of these positions is uncertain. As such, we are unable to make a reasonably reliable estimate regarding the timing of payments beyond twelve months.

Off-Balance Sheet Arrangements

We do not currently have, nor have we ever had, any relationships with unconsolidated entities or financial partnerships, such as entities often referred to as structured finance or special purpose entities, which would have been established for the purpose of facilitating off-balance sheet arrangements or for other contractually narrow or limited purposes. In addition, we do not engage in trading activities involving non-exchange traded contracts.

Recently Issued Accounting Pronouncements

For a discussion of new accounting pronouncements, see Note 2, Summary of Significant Accounting Policies in the Notes to Consolidated Financial Statements in Part II, Item 8 of this report.

ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK.

The primary objective of our investment activities is to preserve our capital to fund operations and to facilitate business development activities. We also seek to maximize income from our investments without assuming significant interest rate risk, liquidity risk, or risk of default by investing in investment grade securities with maturities of four years or less. Our exposure to market risk is confined to investments in cash and cash equivalents, and marketable securities. As of December 31, 2025, we had unrestricted cash and cash equivalents and marketable securities of $308.7 million.

We fully repaid the outstanding principal and interest on the 2023 Notes in April 2023. We borrowed funds pursuant to our Credit Line in connection with the payment of the 2023 Notes. We fully repaid the outstanding debt under the Credit Line in June 2023. In the future, we may borrow funds under the Credit Line. Variable rate borrowing, which may occur under the Credit Line, exposes us to interest rate risk as increases in interest rates would increase our borrowing costs.

Any borrowed funds pursuant to our Credit Line are subject to a collateral maintenance requirement. The Credit Line is secured primarily by our portfolio of marketable securities, which is primarily comprised of corporate and U.S. government agency and municipal debt securities and may fluctuate in value. The fluctuations may be driven by, among other things, changes in interest rates, economic conditions, and other financial conditions as well as idiosyncratic factors related to a security’s issuer. To the extent a fluctuation in value results in the value of the collateral decreasing below the required collateral maintenance requirements we may be required to promptly post additional collateral. Additionally, our Credit Line is an uncommitted facility that may be terminated by the lender at any time. During periods of rapidly changing interest rates, economic conditions or other financial conditions, the Credit Line may be terminated by the lender and/or the lender may declare that all borrowings thereunder are immediately due.

Our cash and cash equivalents consist primarily of cash held at banks and investments in highly liquid financial instruments with an original maturity of three months or less. Our marketable securities, which are reported at fair value, consist of investments in U.S. Treasury bills and notes; bank certificates of deposit; various U.S. governmental agency debt securities; and corporate and municipal debt securities. We place all investments with governmental, industrial, or financial institutions whose debt is rated as investment grade. We generally hold these securities to maturities of one to four years. Because of the relatively short period that we hold our investments and because we generally hold these securities to maturity, we do not believe that an increase in interest rates would have any significant impact on the realizable value of our investments.

We may contract with clinical research organizations (CROs) and investigational sites globally. Currently, we have ongoing clinical trials being conducted outside the U.S. We do not hedge our foreign currency exchange rate risk. Transactions denominated in currencies other than the U.S. dollar are recorded based on exchange rates at the time such transactions arise. As of December 31, 2025, and December 31, 2024, substantially all of our liabilities were denominated in the U.S. dollar.

Inflation generally affects us by increasing our cost of labor and the cost of services provided by our vendors. We do not believe that inflation and changing prices over the years ended December 31, 2025, and 2024 had a significant impact on our consolidated results of operations. While we expect significant year-to-year variability in labor and vendor service costs due to uncontrollable inflation factors like natural disasters, geopolitical conflicts, and government regulations, we strive to mitigate future price risks. We do this by forming strong partnerships with key suppliers and our CMOs, and by directly managing the

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procurement and supply levels of key raw materials for our commercial products. However, these efforts may not fully protect us from cost increases, which could adversely impact our profitability.

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ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA.

Supernus Pharmaceuticals, Inc.

Consolidated Financial Statements

Reports of Independent Registered Public Accounting Firm (PCAOB ID 185) 103

Consolidated Balance Sheets 107

Consolidated Statements of Earnings (Loss) 108

Consolidated Statements of Comprehensive Earnings (Loss) 109

Consolidated Statements of Changes in Stockholders' Equity 110

Consolidated Statements of Cash Flows 111

Notes to Consolidated Financial Statements 112

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Report of Independent Registered Public Accounting Firm

To the Stockholders and Board of Directors

Supernus Pharmaceuticals, Inc.:

Opinion on the ConsolidatedFinancial Statements

We have audited the accompanying consolidated balance sheets of Supernus Pharmaceuticals, Inc. and subsidiaries (the Company) as of December 31, 2025 and 2024, the related consolidated statements of earnings (loss), comprehensive earnings (loss), changes in stockholders’ equity, and cash flows for each of the years in the three-year period ended December 31, 2025, and the related notes (collectively, the consolidated financial statements). In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2025 and 2024, and the results of its operations and its cash flows for each of the years in the three-year period ended December 31, 2025, in conformity with U.S. generally accepted accounting principles.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Company's internal control over financial reporting as of December 31, 2025, based on criteria established in Internal Control - Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission, and our report dated March 2, 2026 expressed an unqualified opinion on the effectiveness of the Company's internal control over financial reporting.

Basis for Opinion

These consolidated financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on these consolidated financial statements based on our audits. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud. Our audits included performing procedures to assess the risks of material misstatement of the consolidated financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the consolidated financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the consolidated financial statements. We believe that our audits provide a reasonable basis for our opinion.

Critical Audit Matter

The critical audit matter communicated below is a matter arising from the current period audit of the consolidated financial statements that was communicated or required to be communicated to the audit committee and that: (1) relates to accounts or disclosures that are material to the consolidated financial statements and (2) involved our especially challenging, subjective, or complex judgments. The communication of a critical audit matter does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the accounts or disclosures to which it relates.

Accrued sales deductions related to product returns

As disclosed in Notes 2 and 16 to the consolidated financial statements, the Company recorded accrued product returns of $37,800 (dollars in thousands) as of December 31, 2025. The related provision for product returns is reflected as a reduction of gross product sales, and is recorded at the time of sale when the customer takes title to the product. Sale of the Company’s products are not subject to a general right of return; however, the Company will accept return of expired product six months prior to and up to 12 months subsequent to the product’s expiry date for certain products. The Company's products have a shelf life of up to 48 months from date of manufacture.

We identified the evaluation of accrued sales deductions related to Trokendi XR, Oxtellar XR and Qelbree product returns, and specifically the assessment of the expected long-term return rates, as a critical audit matter. The assessment of the expected long-term return rates included a comparison to actual returns experience and involved a high degree of auditor judgment due to the significant passage of time between product sale and the time at which the Company issues credit for expired product.

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The following are the primary procedures we performed to address this critical audit matter. We evaluated the design and tested the operating effectiveness of certain internal controls related to the accrued sales deductions process. This included a control over the expected long-term return rate assumptions used in estimating the accrued product returns. We assessed the Company's long-term return rate assumptions by evaluating the consistency of those assumptions with the trend of actual historical return rates. We compared prior period expected long-term return rate assumptions against actual return rates experience.

/s/ KPMG LLP

We have served as the Company's auditor since 2015.

Baltimore, Maryland

March 2, 2026

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Report of Independent Registered Public Accounting Firm

To the Stockholders and Board of Directors

Supernus Pharmaceuticals, Inc.:

Opinion on Internal Control Over Financial Reporting

We have audited Supernus Pharmaceuticals, Inc. and subsidiaries' (the Company) internal control over financial reporting as of December 31, 2025, based on criteria established in Internal Control – Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission. In our opinion, the Company maintained, in all material respects, effective internal control over financial reporting as of December 31, 2025, based on criteria established in Internal Control – Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the consolidated balance sheets of the Company as of December 31, 2025 and 2024, the related consolidated statements of earnings (loss), comprehensive earnings (loss), changes in stockholders’ equity, and cash flows for each of the years in the three-year period ended December 31, 2025, and the related notes (collectively, the consolidated financial statements), and our report dated March 2, 2026 expressed an unqualified opinion on those consolidated financial statements.

The Company acquired Sage Therapeutics, Inc. during 2025, and management excluded from its assessment of the effectiveness of the Company’s internal control over financial reporting as of December 31, 2025, Sage Therapeutics, Inc.’s internal control over financial reporting associated with 9% of total revenues and 7% of total assets included in the consolidated financial statements of the Company as of and for the year ended December 31, 2025. Our audit of internal control over financial reporting of the Company also excluded an evaluation of the internal control over financial reporting of Sage Therapeutics, Inc.

Basis for Opinion

The Company’s management is responsible for maintaining effective internal control over financial reporting and for its assessment of the effectiveness of internal control over financial reporting, included in the accompanying Management's Report on Internal Control over Financial Reporting. Our responsibility is to express an opinion on the Company’s internal control over financial reporting based on our audit. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audit in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether effective internal control over financial reporting was maintained in all material respects. Our audit of internal control over financial reporting included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, and testing and evaluating the design and operating effectiveness of internal control based on the assessed risk. Our audit also included performing such other procedures as we considered necessary in the circumstances. We believe that our audit provides a reasonable basis for our opinion.

Definition and Limitations of Internal Control Over Financial Reporting

A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (2) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.

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Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

/s/ KPMG LLP

Baltimore, Maryland

March 2, 2026

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Supernus Pharmaceuticals, Inc.

Consolidated Balance Sheets

(in thousands, except share and per share data)

Assets

Current assets

Prepaid expenses and other current assets 65,325 36,088

Restricted cash 1,450 —

Deferred income tax assets, net 38,351 —

Liabilities and stockholders' equity

Current liabilities

Accounts payable and accrued liabilities $ 107,800 $ 76,352

Contingent consideration, current portion 31,052 47,340

Other current liabilities 38,222 —

Contingent consideration, long-term 206 —

Operating lease liabilities, long-term 30,365 27,382

Deferred income tax liabilities, net — 4,961

Commitments and contingencies (Note 18)

Stockholders' equity

Accumulated other comprehensive loss, net of tax (44) (189)

See accompanying notes.

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Supernus Pharmaceuticals, Inc.

Consolidated Statements of Earnings (Loss)

(in thousands, except share and per share data)

Year Ended December 31,

Revenues

Collaboration revenue (ZURZUVAE) 52,996 — —

Costs and expenses

Intangible asset impairment charges — — 20,189

Other income (expense)

Interest expense — — (2,415)

Earnings (Loss) per share

Weighted average shares outstanding

(a)Excludes amortization of intangible assets.

See accompanying notes.

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Supernus Pharmaceuticals, Inc.

Consolidated Statements of Comprehensive Earnings (Loss)

(in thousands)

Year Ended December 31,

Other comprehensive gain (loss)

Unrealized gain (loss) on marketable securities, net of tax 145 404 2,617

See accompanying notes.

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Supernus Pharmaceuticals, Inc.

Consolidated Statements of Changes in Stockholders' Equity

(in thousands, except share data)

Shares Amount

Unrealized gain on marketable securities, net of tax — — — 2,617 — 2,617

Unrealized gain on marketable securities, net of tax — — — 404 — 404

Unrealized gain on marketable securities, net of tax — — — 145 — 145

See accompanying notes.

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Supernus Pharmaceuticals, Inc.

Consolidated Statements of Cash Flows

(in thousands)

Year Ended December 31,

Cash flows from operating activities

Intangible asset impairment charges — — 20,189

Amortization of deferred financing costs and debt discount — — 532

Realized loss (gains) from sales of marketable securities 439 (9) —

Amortization of premium/discount on marketable securities (1,529) 1,823 (122)

Change in fair value of contingent consideration 25,419 (6,110) (1,517)

Payment of contingent consideration (4,900) — —

Changes in operating assets and liabilities:

Cash flows from investing activities

Acquisition of Sage, net of cash acquired (293,093) — —

Purchases of property and equipment (1,338) (725) (551)

Cash flows from financing activities

Proceeds from Credit Line — — 93,000

Payments on Credit Line — — (93,000)

Payment on convertible notes — — (402,500)

Payment of contingent consideration (24,257) — —

Restricted cash 1,450 — —

Supplemental cash flow information

Cash paid for interest on debt $ — $ — $ 1,946

See accompanying notes.

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Supernus Pharmaceuticals, Inc.

Notes to Consolidated Financial Statements

1. Business Organization

Supernus Pharmaceuticals, Inc. (the Company, see Consolidation in Note 2, Summary of Significant Accounting Policies) was incorporated in Delaware and commenced operations in 2005. The Company is a biopharmaceutical company focused on developing and commercializing products for the treatment of central nervous system (CNS) diseases. The Company's 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. The Company is developing a broad range of novel product candidates for CNS disorders.

The Company has nine commercial products: Qelbree®, GOCOVRI®, Oxtellar XR®, APOKYN®, Trokendi XR®, XADAGO®, MYOBLOC®, ONAPGOTM,(formerly known as SPN-830), and ZURZUVAE® (see Note 3, Sage Acquisition). In February 2025, the FDA approved ONAPGO (apomorphine hydrochloride) injection as the first and only subcutaneous apomorphine infusion device for the treatment of motor fluctuations in adults with advanced PD. ONAPGO was launched in April 2025. In September 2025, the Federal Drug Administration (FDA) withdrew the New Drug Application (NDA) for OSMOLEX ER.

Acquisition of Sage Therapeutics, Inc. and Reorganization

On June 13, 2025, the Company entered into an Agreement and Plan of Merger (Merger Agreement) to acquire Sage Therapeutics, Inc. (Sage). The acquisition closed on July 31, 2025.

Sage was a pharmaceutical company with a portfolio of product candidates to address a range of neurological diseases and a commercial product to treat PPD. Sage's commercialized product, ZURZUVAE® (zuranolone) capsules, is the first and only FDA-approved oral medicine indicated for the treatment of postpartum depression in adults. As of July 31, 2025, Sage became a wholly-owned subsidiary of the Company. With the acquisition of Sage, the Company acquired the rights to further develop and market ZURZUVAE. Through a collaboration agreement with Biogen MA Inc. (BIMA) and Biogen International GmbH (together with BIMA, Biogen), the Company reports collaboration revenue that is 50% of total net revenue recorded by Biogen for ZURZUVAE in the United States (U.S.). See Note 3, Sage Acquisition, for further details on the acquisition and Note 15, Collaboration Agreements, for further details on the collaboration agreement with Biogen.

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

2. Summary of Significant Accounting Policies

Basis of Presentation

The Company's consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States (U.S. GAAP).

The Company, which is primarily located in the United States (U.S.), operates in one operating segment.

Consolidation

The Company's consolidated financial statements include the accounts of Supernus Pharmaceuticals, Inc. and its wholly-owned subsidiaries. These are collectively referred to herein as "Supernus" or "the Company." Supernus Pharmaceuticals, Inc. and each of its subsidiaries are distinct legal entities. All material intercompany transactions and balances have been eliminated in consolidation.

The consolidated financial statements reflect the consolidation of entities in which the Company has a controlling financial interest. In determining whether there is a controlling financial interest, the Company considers if it has a majority of the voting interests of the entity, or if the entity is a variable interest entity (VIE) and if the Company is the primary beneficiary. In determining the primary beneficiary of a VIE, the Company evaluates whether it has both: the power to direct the activities of the VIE that most significantly impact the VIE's economic performance; and the obligation to absorb losses of, or the right to receive

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benefits from, the VIE that could potentially be significant to that VIE. The Company's judgment with respect to its level of influence or control of an entity involves the consideration of various factors, including the form of an ownership interest; representation in the entity's governance; the size of the investment; estimates of future cash flows; the ability to participate in policymaking decisions; and the rights of the other investors to participate in the decision making process, including the right to liquidate the entity, if applicable. If the Company is not the primary beneficiary of the VIE, and an ownership interest is maintained in the entity, the interest is accounted for under the equity or cost methods of accounting, as appropriate.

The Company continuously assesses whether it is the primary beneficiary of a VIE as changes to existing relationships or future transactions may affect its conclusions.

Use of Estimates

The Company bases its estimates on: historical experience; forecasts; information received from its service providers; information from other sources, including public and proprietary sources; and other assumptions that the Company believes are reasonable under the circumstances. Actual results could differ materially from the Company’s estimates. The Company periodically evaluates the methodologies employed in making its estimates.

Cash and Cash Equivalents

The Company considers all investments in highly liquid financial instruments with an original maturity of three months or less to be cash equivalents.

Accounts Receivable, Net

The Company's trade accounts receivable arise from product sales and represents amounts due from its customers. In addition, the Company records accounts receivable arising from its collaboration and licensing agreements. The Company monitors the financial performance and credit worthiness of its counterparties so that it can properly assess and respond to changes in their credit profile. The Company provides allowances against receivables for estimated losses, if any, that may result from a counterparty's inability to pay. Amounts determined to be uncollectible are written-off against the allowance.

Marketable Securities

Marketable securities consist of investments in U.S. Treasury bills and notes; bank certificates of deposit; various U.S. government agency debt securities; corporate and municipal debt securities. The Company places all investments with governmental, industrial, or financial institutions whose debt is rated as investment grade.

The Company's investments are classified as available-for-sale and are carried at fair value. The Company classifies all available-for-sale marketable securities with maturities greater than one year from the balance sheet date as non-current assets.

Any unrealized holding gains or losses on debt securities, including their tax effect, are reported as components of Other comprehensive gain (loss) in the consolidated statement of comprehensive earnings (loss). Realized gains and losses, included in Interest and other income, net in the consolidated statement of earnings (loss), are determined using the specific identification method for determining the cost of securities sold.

Declines in fair value below amortized cost related to credit losses (i.e., impairment due to credit losses) are included in the consolidated statement of earnings (loss), with a corresponding allowance established. If the estimate of expected credit losses decreases in subsequent periods, the Company will reverse the credit losses through current period earnings and adjust the allowance accordingly.

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Business Combinations and Contingent Consideration

The Company determines whether an acquisition should be accounted for as a business combination or as an asset acquisition. If the acquired set of activities and assets does not meet the definition of a business, as defined by U.S. GAAP, the transaction is accounted for as an asset acquisition. In an asset acquisition, any acquired research and development that does not have an alternative future use is charged to expense as of the acquisition date, and no goodwill is recorded. If the acquired set of activities and assets meets the definition of a business, the Company applies the acquisition method of accounting and accounts for the transaction as a business combination. In a business combination, assets acquired and liabilities assumed are recorded at their respective fair values as of the acquisition date. The excess of the purchase price over the fair value of the acquired net assets, if applicable, is recorded as goodwill.

In a business combination, the operating results of the acquired business are included in the Company's consolidated statement of earnings (loss), beginning on the effective acquisition date. Acquisition-related expenses are recognized separately from the business combination and are expensed as incurred.

Significant judgment is involved in the determination of the fair value assigned to assets acquired and liabilities assumed in a business combination, as well as the estimated useful lives of assets. These estimates can materially affect the Company's consolidated results of operations and financial position. The fair value of intangible assets are determined using information available as of the acquisition date and are based on estimates and assumptions that are deemed reasonable by management. Significant estimates and assumptions include but are not limited to: the probability of regulatory approval, revenue growth, and appropriate discount rate.

While the Company uses its best estimates and assumptions to accurately value assets acquired and liabilities assumed as of the acquisition date, estimates are inherently uncertain and subject to refinement. As a result, during the measurement period, which may be up to one year from the acquisition date, the Company may record adjustments to the assets acquired and liabilities assumed with the corresponding offset to goodwill.

Upon the conclusion of the measurement period, any subsequent adjustments are recorded to the Company's consolidated statements of earnings (loss) in the period that these adjustments are identified.

Additional information regarding the Company's recent business combination is included in Note 3, Sage Acquisition.

Contingent Consideration

Business combinations often include provisions for additional consideration to be transferred to former shareholders based upon the achievement of certain milestones, referred to as contingent consideration. Contingent consideration from product development milestones and sales-based milestone payments on future product sales are included in the purchase price for business combinations. The fair value of the contingent consideration liability is determined as of the acquisition date using estimated or forecasted inputs. These inputs include the estimated amount and timing of projected revenues, probability and timing of milestone achievement, probability of achieving regulatory approval, revenue volatility, and the estimated discount rates and risk-free rate used to present value the probability-weighted cash flows. Subsequent to the acquisition date, at each reporting period prior to the resolution of the contingency, the contingent consideration liability is remeasured at current fair value, with changes recorded in earnings in the period of remeasurement.

The determination of the initial and subsequent fair value of the contingent consideration liability may require significant judgment by management. Changes in any of the inputs not related to facts and circumstances existing as of the acquisition date may result in a significant fair value adjustment, which can impact the results of operations in the period in which the adjustment is made. Changes that are not measurement period adjustments are reported on the consolidated statement of earnings (loss) in Contingent consideration loss (gain).

Additional information regarding contingent consideration, including the contingent consideration arrangement resulting from the Company's recent business combination, is included in Note 7, Contingent Consideration.

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Concentration of Credit Risk

Financial instruments that potentially subject the Company to credit risk concentrations consist of cash, cash equivalents, marketable securities, and accounts receivable. The counterparties are various corporations, governmental institutions, and financial institutions of high credit standing.

Substantially all of the Company's cash, cash equivalents, and marketable securities are maintained in U.S. Treasury bills and notes; bank certificates of deposit; various U.S. governmental agency debt securities; and corporate and municipal debt securities. The Company places all investments with governmental, industrial, or financial institutions whose debt is rated as investment grade. Deposits held with banks may exceed the amount of governmental insurance provided on such deposits. Generally, these deposits may be redeemed upon demand, and therefore, these bear minimal default risk.

The following table shows the percentage of the Company's sales made to customers representing more than 10% of the Company's total gross product sales, and the percentage of the Company's accounts receivables, net from each:

Percentage of Gross Product Sales Percentage of Accounts Receivable, net

Refer to Note 4, Disaggregated Revenues, for the concentration of net product sales.

Inventories

Inventories are recorded at the lower of cost or net realizable value, and include materials, labor, direct costs and indirect costs. These are valued using the first-in, first-out method. Prior to the initial date that regulatory approval is received for a product candidate of the Company, costs related to the production of inventory are recorded as research and development expense on the Company’s consolidated statements of earnings (loss) in the period incurred. Raw and intermediate materials that may be utilized for either research and development or commercial purposes, after approval of the product by the FDA, are classified as inventory. Amounts in inventory that are used for research and development purposes are charged to research and development expense when the product enters the research and development process and can no longer be used for commercial purposes and, therefore, does not have an “alternative future use” as defined in authoritative guidance. The Company has acquired inventory from the Sage Acquisition, and recorded a corresponding liability related to this inventory, which represents the consideration paid by a customer to the Company for inventory cost as part of the Collaboration Agreement.

The Company periodically reviews inventory and records write-downs for any excess, expired and obsolete inventory, and for inventory that has a cost basis in excess of its expected net realizable value based on estimates of product demand, production requirements, market conditions, regulatory requirements and spoilage. The write-down to net realizable value is recorded in the period in which impairment is identified and is recorded as a component of Cost of revenues in the consolidated statement of earnings (loss).

The Company expects to use the inventory that is classified within current assets on its consolidated balance sheet over its operating cycle. Inventory that is not expected to be used over the Company’s operating cycle is classified as a non-current asset and is included in Other assets in the consolidated balance sheet.

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Property and Equipment

Property and equipment are stated at cost. Upon retirement or sale, the cost of assets disposed of and the related accumulated depreciation are removed from the accounts and any resulting gain or loss is credited or charged to operations. Repairs and maintenance costs are expensed as incurred. Depreciation and amortization are computed using the straight-line method over the following useful lives:

Computer equipment 3 years - 5 years

Software 3 years - 5 years

Lab equipment and furniture 5 years - 10 years

Leasehold improvements Shorter of lease term or useful life

Intangible Assets

Intangible assets consist of definite-lived intangible assets, including: acquired developed technology and product rights intangible, and patent defense costs. They also consist of indefinite-lived intangible assets, such as acquired in-process research and development (IPR&D) and goodwill.

Patent defense costs are deferred legal fees that have been incurred in connection with legal proceedings related to the defense of patents for Oxtellar XR and Trokendi XR. Patent defense costs are charged to expense in the event of an unsuccessful outcome of the litigation.

Definite-lived intangible assets (including acquired developed technology and product rights) are carried at acquisition date fair value less accumulated amortization, with amortization calculated on a straight line basis over the estimated useful lives. The Company evaluates the estimated remaining useful lives of its intangible assets annually or when events or changes in circumstances warrant a revision to the remaining periods of amortization.

Acquired IPR&D in a business combination is considered an indefinite-lived intangible asset until the completion or abandonment of the associated research and development efforts. Upon successful completion of the project, the Company will determine the then-useful life of the intangible asset. This is generally determined as the period over which the substantial majority of the cash flows are expected to be generated. The capitalized amount is then amortized over its estimated useful life. If a project is abandoned, all remaining capitalized amounts are written off immediately. During the period prior to completion or abandonment, the IPR&D asset is not amortized but tested for impairment on an annual basis or when potential indicators of impairment are identified.

Impairment of Long-Lived Assets

Long-lived assets consist primarily of property and equipment, operating lease assets, and definite-lived intangible assets. The Company assesses the recoverability of its long-lived assets with definite lives whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If indications of impairment exist, projected future undiscounted cash flows associated with the asset would be compared to the carrying value of the asset to determine whether the asset's value is recoverable. If impairment is determined, the Company writes down the asset to its estimated fair value and records an impairment loss equal to the excess of the carrying value of the long-lived asset over its estimated fair value in the period at which such a determination is made.

Goodwill and Goodwill Impairment Assessment

Goodwill is calculated as the excess of the consideration paid consequent to completing the acquisition, compared to the net assets recognized in a business combination and is recognized at acquisition date. Goodwill represents the future economic benefits from the other acquired assets that could not be individually identified and separately quantified.

The Company evaluates goodwill for possible impairment at least annually (during the fourth quarter of each fiscal year), or more often, if and when events and circumstances indicate that goodwill may be impaired. The annual evaluation is generally

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based on an assessment of qualitative factors to determine whether it is more likely than not that the fair value of the asset is less than its carrying amount. This includes but is not limited to, significant adverse changes in the business climate, market conditions, or other events that indicate that it is more likely than not that the fair value of the reporting unit is less than its carrying value. If the Company is unable to conclude whether the goodwill is not impaired after considering the totality of events and circumstances during its qualitative assessment, the Company performs a quantitative assessment by estimating the fair value of the reporting unit and comparing the fair value to the carrying amount. Evaluating for impairment requires judgment, including identifying reporting units and estimating future cash flows. The Company estimates the fair values of its reporting unit using discounted cash flow models or other valuation models, such as comparative transactions or market multiples. If the carrying amount of the reporting unit exceeds its fair value, the Company writes down the goodwill to the estimated fair value, and an impairment loss equal to the difference is recognized in the consolidated statement of earnings (loss) in the period at which such determination is made.

Revenue Recognition

The Company determines revenue recognition for its contractual arrangements with customers based on the following five steps: (1) identify each contract with a customer; (2) identify the performance obligations in the contract; (3) determine the transaction price; (4) allocate the transaction price to the performance obligations in the contract; and (5) recognize revenue when (or as) the Company satisfies the relevant performance obligation. The Company only applies the five-step model to contracts when it is probable that the Company will collect the consideration it is entitled to in exchange for the goods or services it transfers to the customer. The Company recognizes revenue in an amount that reflects the consideration the Company expects to receive in exchange for those goods or services. The Company does not adjust revenue for any financing effects in transactions where the Company expects the period between the transfer of the goods or services and collection to be less than one year.

The Company has no contract assets as of December 31, 2025 or 2024. The Company has $3.1 million of contract liabilities as of December 31, 2025, and no contract liabilities as of December 31, 2024.

Revenue from Product Sales

The Company's customers are primarily pharmaceutical wholesalers, specialty pharmacies, and pharmaceutical distributors. Customers purchase product to fulfill orders from retail pharmacy chains and independent pharmacies of varying size and purchasing power. The Company recognizes gross product sales when its customers take control of its products, including title and ownership. Customer orders are generally fulfilled within a few days of order receipt, resulting in minimal order backlog.

The Company recognizes revenue from product sales in an amount that reflects the consideration the Company expects to ultimately receive in exchange for those goods. Product sales are recorded net of various forms of variable consideration, including: provision for estimated rebates; provision for estimated future product returns; and an estimated provision for discounts. These are collectively considered sales deductions. Sales deductions are based on estimates of the amounts earned or to be claimed on the related sales. These amounts are treated as variable consideration, estimated and recognized as a reduction of the transaction price at the time of sale using the most likely value method. The Company includes these estimated amounts in the transaction price to the extent it is probable that a significant reversal will not occur.

Variability in the net transaction price for the Company's products arises primarily from the aforementioned sales deductions. Significant judgment is required in estimating certain sales deductions. In making these estimates, the Company considers: historical experience; product price increases; current contractual arrangements under applicable payor programs; unbilled claims; processing time lags for claims; inventory levels in the wholesale, specialty pharmacy, and retail distribution channel; and product life cycle. The Company adjusts its estimates of revenue either when the most likely amount of consideration it expects to receive changes, or when the consideration becomes fixed. If actual results in the future vary from its estimates, the Company adjusts its estimates in the period identified. These adjustments could materially affect net product sales and earnings in the period in which the adjustment(s) is recorded.

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Sales Deductions

The Company records product sales net of rebates, returns and discounts.

•Rebates - Rebates are discounts which the Company pays under either public sector or private sector health care programs. Rebates paid under public sector programs are generally mandated under law, whereas private sector rebates are generally contractually negotiated by the Company with managed care providers. Both types of rebates vary over time. Rebates are owed when the Company's customer dispenses the Company's product to a patient; i.e., filling a prescription. For each of its products, the Company bases its estimates of expected rebate claims on multiple factors, including: historical levels of deductions; contractual terms with managed care providers; actual and anticipated changes in product price; prospective changes in managed care fee for service contracts; prospective changes in co-payment assistance programs; and anticipated changes in program utilization rates; i.e., patient participation rates under each specific program. The Company records an estimated liability for rebates at the time the customer takes title to the product (i.e., at the time of sale to wholesalers/distributors). This liability is recorded as a reduction to gross product sales, and an increase in Accrued product returns and rebates. The liability is recorded as a component of current liabilities on the consolidated balance sheets.

•Returns - Sales of the Company's products are not subject to a general right of return. A product that has been used to fill patient prescriptions is no longer subject to any right of return. However, the Company will accept a return of product that is damaged or defective when shipped from its third party fulfillment centers. The Company will also accept a return of expired product six months prior to and up to twelve months subsequent to the product's expiry date for certain products. Expired or defective returned product cannot be re-sold and is therefore destroyed. The Company records an estimated liability for product returns at the time the customer takes title to the product (i.e., at time of sale). The liability is reflected as a reduction to gross product sales, and an increase in Accrued product returns and rebates. This liability is recorded as a component of current liabilities on the consolidated balance sheets. The Company estimates the liability for returns primarily based on the actual returns experience for its commercial products. Because the Company's products have a shelf life up to forty-eight months from the date of manufacture, and because the Company accepts return of product up to twelve months post its expiry date, there is a time lag of several years between the time when the product is sold and the time when the Company may issue credit on the expired product.

•Sales discounts - Distributors and wholesalers of the Company's pharmaceutical products are generally offered various forms of consideration, including allowances, service fees and prompt payment discounts, for distributing our products. Distributor and wholesaler allowances and service fees arise from contractual agreements and are estimated as a percentage of the price at which the Company sells product to them. In addition, distributors and wholesalers are offered a prompt pay discount for payment within a specified period. Prompt pay discounts are estimated as a percentage of the price at which the Company sells product. The Company accounts for these discounts at the time of sale as a reduction to gross product sales and Accounts receivable, net.

Royalty, Licensing, Collaboration, and Other Revenues

Royalty Revenues

Royalty revenues include cash royalty amounts received from third parties pursuant to settlement agreements and agreements with collaboration partners for the right to use the Company's intellectual property as a functional license. These agreements may include sales-based royalties on the licensed intellectual property to which the royalties relate and milestone payments based on the level of sales (collectively, sales-based royalties). For arrangements that include sales-based royalties and the license is deemed to be the predominant item to which the royalties relate, the Company recognizes revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied). If it is probable that a significant revenue reversal will not occur, the Company will estimate the royalty revenues using the most likely amount method. Certain of the Company’s royalty revenues are recognized by the Company based on information supplied to the Company by its licensees and require estimates to be made. Sales-based royalties are recorded based on estimated net sales of the underlying product. Differences between actual royalty revenues and estimated royalty revenues are reconciled and adjusted for in the period in which they become known, which is generally within the following quarter. The difference between the Company’s actual and estimated royalty revenues has not been material to date.

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Historically, royalty revenues also included noncash royalty revenues for amounts earned pursuant to its royalty agreement with United Therapeutics Corporation (United Therapeutics) and was based on estimated product sales of Orenitram by United Therapeutics. During the second quarter of 2023, full ownership of the royalty rights has reverted back to the Company as the cumulative payment threshold has been reached (see Note 4, Disaggregated Revenues).

There are no guaranteed amounts owed to the Company related to any of these royalty revenue agreements.

License Revenues

The Company's agreements with third parties generally involve the right to use the Company's intellectual property as a functional license. Certain agreements include an up-front license fee and ongoing milestone payments upon the achievement of specific events, and may also require minimum royalty payments based on in-country sales of products developed from the applicable intellectual property.

In determining when to recognize the revenue under a collaboration agreement, the Company assesses whether the license is distinct, which depends upon whether the customer can benefit from the license and whether the license is separate from other performance obligations in the agreement. If the license is distinct, the Company must further assess whether the customer has a right to access or a right to use the license depending on whether the functionality of the license is expected to substantively change over time. If the license is not expected to substantively change, the revenue is recognized at the point in time when the license is provided. Generally, the Company recognizes revenues from non-refundable up-front fees allocated to the license at a point in time, when the license is transferred to the licensee and the licensee is able to use and benefit from the license.

Revenue recognition from milestone payments is dependent upon the facts and circumstances surrounding the milestone payments. Generally, milestone payments under the Company’s collaboration agreements with third parties are non-refundable. The Company evaluates whether achieving the milestones is considered probable and estimates the amount to be included in the transaction price using the most likely amount method. This can involve management's judgment that includes assessing factors that are outside of the Company's influence, such as: likelihood of regulatory success; availability of third party information; and expected duration of time until achievement of event. These factors are evaluated based on the specific facts and circumstances. If it is probable that a significant revenue reversal would not occur, the value of the associated milestone is included in the transaction price.

Milestone payments based on a non-sales metric such as a development-based milestone (e.g. obtaining regulatory approval) represent variable consideration and would be included in the transaction price subject to any constraints. If the milestone payments relate to future development, the timing of recognition depends upon historical experience, the specific facts and circumstances, and the significance a third-party has on the outcome. Milestone payments that are not within the control of the Company, such as approval from regulatory authorities or where attainment of the specified event is dependent on the development activities of a third-party, are fully constrained and are not included in the transaction price until the period in which those regulatory approvals are obtained, or the specified event occurs due to the inherent uncertainty with the approval process.

For milestone payments to be received upon the achievement of a sales threshold, the revenue from the milestone payments is recognized at the later of when the actual sales are incurred or the performance obligation to which the sales relate has been satisfied as noted below.

Collaborative Arrangements

At contract inception, the Company analyzes its collaboration arrangements to assess whether they are within the scope of Accounting Standards Codification Topic 808, Collaborative Arrangements (ASC 808) to determine whether such arrangements involve joint operating activities performed by parties that are both active participants in the activities and exposed to significant risks and rewards dependent on the commercial success of such activities. This assessment is performed throughout the life of the arrangement based on changes in the responsibilities of all parties in the arrangement. For collaboration arrangements within the scope of ASC 808 that contain multiple elements, the Company first determines which elements of the collaboration are deemed to be within the scope of ASC 808 and those that are more reflective of a vendor-customer relationship and therefore within the scope of Accounting Standards Codification Topic 606, Revenue from Contract with Customers, (ASC 606). For elements of collaboration arrangements that are accounted for pursuant to ASC 808, an appropriate recognition method

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is determined and applied consistently, either by analogy to authoritative accounting literature or by applying a reasonable and rational policy election.

For those elements of the arrangement that are accounted for pursuant to ASC 606, the Company performs the five-step model under ASC 606 as noted above to determine the appropriate amount of revenue to be recognized as it fulfills its obligations under each of its agreements and presents the arrangement as Royalty, licensing and other revenue or Collaboration revenue (ZURZUVAE) in the consolidated statements of earnings (loss).

For those elements of the arrangement that are accounted for pursuant to ASC 808, the Company evaluates the income statement classification for presentation of amounts due from or owed to other participants associated with multiple activities in a collaboration arrangement based on the nature of each separate activity. Payments or reimbursements that are the result of a collaborative relationship instead of a vendor-customer relationship are recorded as an increase to Collaboration revenue (ZURZUVAE), an increase to or reduction of Cost of revenues, Research and development expense, or Selling, general and administrative expense, depending on the nature of the activity.

The Company applies ASC 808 and ASC 606 to the following collaboration agreements:

•Biogen - The Company has a collaboration agreement with Biogen (Biogen Collaboration Agreement) for the co-commercialization of ZURZUVAE in the U.S. Since the acquisition of Sage, revenues from the Biogen Collaboration Agreement include the Company’s share of ZURZUVAE revenues as that element of the agreement is accounted for under ASC Topic 808. The Company reports as Collaboration revenue (ZURZUVAE) its share of ZURZUVAE revenues, which is 50% of total net revenue recorded by Biogen for ZURZUVAE in the U.S.

The Company also identified the following promises in the Biogen Collaboration Agreement that were evaluated under the scope of ASC 606: delivery of (i) a co-exclusive license for SAGE-217 products in the U.S.; (ii) an exclusive license for SAGE-217 products outside of the United States other than Japan, the Republic of Korea, and Taiwan (Biogen Territory); (iii) commercial manufacturing supply of active pharmaceutical ingredient (API) and bulk drug product for SAGE-217 products in the Biogen Territory, and (iv) commercial manufacturing supply of API and bulk drug product for SAGE-217 in the U.S.

The Company also evaluated whether certain options outlined within the Biogen Collaboration Agreement represented material rights that would give rise to a performance obligation and concluded that none of the options convey a material right to Biogen and therefore are not considered separate performance obligations within the Biogen Collaboration Agreement.

The Company assessed the above promises at contract inception and determined that the co-exclusive license for SAGE-217 products in the U.S. is reflective of a vendor-customer relationship and therefore represent performance obligations within the scope of ASC 606. The co-exclusive license for SAGE-217 products in the U.S. is considered functional intellectual property and distinct from other promises under the contract. The exclusive license for SAGE-217 products in the Biogen Territory is considered a functional license that is distinct in the context of the Biogen Collaboration Agreement as Biogen can benefit from the license on its own or together with other readily available resources. As the co-exclusive license in the U.S. and the exclusive license in the Biogen Territory are delivered at the same time, they are considered one performance obligation at contract inception. The commercial manufacturing supply of API and bulk drug product for SAGE-217 products for the Biogen Territory, as well as in the U.S., are considered distinct in the context of the Biogen Collaboration Agreement as Biogen can benefit from the manufacturing services together with the licenses transferred by the Company at the inception of the Biogen Collaboration Agreement. Therefore, each represents a separate performance obligation within a contract with a customer under the scope of ASC 606 at contract inception and is recorded in Royalty, licensing, and other revenues.

•Shionogi - The Company also has a collaboration agreement with Shionogi & Co., Ltd. (Shionogi) (Shionogi Collaboration Agreement) whereby the Company is entitled to receive royalties and milestone payments upon achievement of certain milestones. The Shionogi Collaboration Agreement also includes arrangement for the supply of drug product for Shionogi’s clinical trials. The Company concluded that Shionogi meets the definition of a customer because the Company is delivering intellectual property and know-how rights for the zuranolone program in support of

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territories in which the parties are not jointly sharing the risks and rewards. In addition, the Company determined that the Shionogi Collaboration Agreement met the requirements to be accounted for as a contract, including that it is probable that the Company will collect the consideration to which the Company is entitled in exchange for the goods or services that will be delivered to Shionogi. The Company assessed the promises at contract inception and determined that the license to zuranolone and supply of products to Shionogi are reflective of a vendor-customer relationship and therefore represent performance obligations within the scope of ASC 606.

The Company determined that the performance obligations in the Shionogi Collaboration Agreement included the license to zuranolone and the supply of certain materials during the clinical development phase, which includes the supply of API. The performance obligation related to the license to zuranolone was determined to be distinct from other performance obligations and therefore was a separate performance obligation for which control was transferred upon signing, and is recorded in Royalty, licensing, and other revenues. The obligation to provide certain clinical materials, including API for use during the development period, was determined to be a separate performance obligation, and is recorded in Royalty, licensing, and other revenues.

For additional information on the collaboration agreements with Biogen and Shionogi, as well as the Company's other collaboration arrangements, refer to Note 15, Collaboration Agreements.

Cost of Revenues

Costs of revenues includes primarily cost of materials; third-party manufacturing costs; freight and distribution costs; direct labor; cost of royalties; cost to write down inventory to net realizable value; manufacturing overhead costs, including quality control and assurance; and may also include period costs related to certain inventory manufacturing services. Fair value of inventories acquired through business combinations or asset acquisitions include an inventory step-up within the value of inventories. The inventory step-up value is amortized as the related inventory is sold, and included in Costs of revenues. Costs of revenues also includes our proportionate share of ZURZUVAE manufacturing costs under the Biogen Collaboration Agreement, (for additional information, refer to Note 15, Collaboration Agreements).

Research and Development Expenses

Research and development expenditures are expensed as incurred. These expenses include: employee salaries, benefits, and share-based compensation; cost of contract research and development services provided by third parties; costs for preclinical and clinical studies; cost of acquiring or manufacturing clinical trial materials; regulatory costs; research facilities costs; depreciation expense and allocated occupancy expenses; and license fees and milestone payments related to in-licensed products and technologies. Acquired IPR&D assets that are used for research and development and have no future alternative use are expensed as incurred in research and development.

The Company estimates preclinical and clinical trial expenses based on services performed pursuant to contracts with research institutions, clinical investigators, clinical research organizations (CROs), and other service providers that perform services on the Company's behalf. In recording service fees, the Company estimates the cost of those services performed on behalf of the Company during the current period and compares those costs with the cumulative expenses recorded and payments made for such services. As appropriate, the Company accrues additional expense for services that have been delivered or defers nonrefundable advance payments until the related services are performed.

If the actual timing of the performance of services or the level of effort varies from its estimate, the Company adjusts its accrued expenses, or its deferred advance payments, accordingly. If the Company subsequently determines that it no longer expects the services associated with a nonrefundable advance payment to be rendered, the remaining portion of that advance payment is charged to expense in the period in which such determination is made.

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Notes to Consolidated Financial Statements (Continued)

2. Summary of Significant Accounting Policies (Continued)

Share-Based Compensation

Stock Options

The Company recognizes share-based compensation expense over the service period, using the straight-line method. Employee share-based compensation for stock options is determined using the Black-Scholes option-pricing model to compute the fair value of option grants as of their grant date. Forfeitures are accounted for as incurred. The Company uses the following assumptions for estimating the fair value of option grants:

•Fair Value of Common Stock—The fair value of the common stock underlying the option grants is determined based on observable market prices of the Company's common stock.

•Expected Volatility—Volatility is a measure of the amount by which the Company's share price has historically fluctuated or is expected to fluctuate on a daily basis and is expected to fluctuate (i.e., expected volatility) in the future.

•Expected Dividend Yield—The Company has never declared or paid dividends and has no plans to do so in the foreseeable future. The expected dividend yield is therefore zero.

•Expected Term—This is the period of time during which options are expected to remain unexercised. The Company determines the expected term based on the historical exercise behavior of the stock option plan participants. Options have a maximum contractual term of ten years.

•Risk-Free Interest Rate—This is the observed U.S. Treasury Note rate as of the week each option grant is issued, with a term that most closely resembles the expected term of the option.

Restricted Stock Units (RSUs)

Share-based compensation expense is recorded based on amortizing the fair market value of the RSU as of the date of the grant over the implied service period. RSUs granted to employees generally vest over four equivalent annual installments, starting on the first anniversary of the grant. RSUs granted to directors generally vest over a one year term. Forfeitures are accounted for as incurred.

Performance Stock Units (PSUs)

Performance-Based Awards

Share-based compensation expense for performance-based awards is recognized based on amortizing the fair market value of the award as of the grant date over the periods during which the achievement of the performance target is probable. Performance-based awards require certain performance targets to be achieved in order for the award to vest. Vesting occurs on the date of achievement of the performance target. Forfeitures are accounted for as incurred.

Market-Based Awards

Share-based compensation expense for market-based awards is recognized on a straight-line basis over the requisite service period, regardless of whether the market condition has been satisfied. Market-based PSU awards vest upon the achievement of the performance target. Forfeitures are accounted for as incurred.

The Company estimates the fair value of these awards as of the grant date using a Monte Carlo simulation that incorporates option-pricing inputs. This simulation covers the period from the grant date through the end of the derived requisite service period. Volatility as of the grant date is estimated based on historical daily volatility of the Company's common stock over a period of time, which is equivalent to the expected term of the award. The risk-free interest rate is based on the U.S. Treasury Note rate, as of the week, the award is issued, with a duration that most closely resembles the expected term of the award.

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Notes to Consolidated Financial Statements (Continued)

2. Summary of Significant Accounting Policies (Continued)

Leases

The Company determines if an arrangement is a lease considering whether there is an identified asset, and the contract conveys the right to control its use. Leases with an initial term of twelve months or less are not recorded on the balance sheet. Right-of-use (ROU) assets and lease liabilities are recognized at the commencement date based on the present value of remaining lease payments over the lease term. For this purpose, the Company considers only payments that are fixed and determinable at the time of commencement. The Company calculates the present value of future payments by using an estimated incremental borrowing rate, which approximates the rate at which the Company would borrow, on a secured basis and over a similar term. This rate is estimated based on information available at the commencement date of the lease and may differ for individual leases or portfolios of leased assets. Additionally, for certain equipment leases, the Company applies a portfolio approach to effectively account for the operating lease ROU assets and lease liabilities.

Lease expense for operating leases is recognized on a straight-line basis over the expected lease term and recognized as an operating cost.

Some of the Company's leases include options to terminate prior to the end of the lease term or to extend the lease for one or more years. These options are included in the lease term when it is reasonably certain that the option will be exercised.

The Company's lease agreements may contain variable costs such as common area maintenance, insurance, real estate taxes, or other costs. Variable lease costs are expensed as incurred on the consolidated statements of earnings (loss). The Company's lease agreements generally do not contain any material residual value guarantees or material restrictive covenants.

Advertising Expense

Advertising expense includes the cost of promotional materials and activities, such as print materials and digital marketing, marketing programs and speaker programs. The cost of the Company's advertising efforts are expensed as incurred.

The Company incurred approximately $96.1 million, $88.5 million, and $99.7 million in advertising expense for the years ended December 31, 2025, 2024, and 2023, respectively. These expenses are recorded as a component of Selling, general and administrative expenses in the consolidated statements of earnings (loss).

Insurance Recoveries

The Company has several policies with third-party insurers that provide for the recovery of certain costs incurred by the Company. The Company records its rights to insurance recoveries as a receivable when the respective costs are reimbursable under applicable insurance policies, it is probable that such costs will be reimbursed, and reimbursement can be reasonably estimated. As such, the Company estimates the percentage of costs that will be reimbursed by the insurance provider to determine the amount to record for the insurance recovery receivable.

Insurance recoveries recognized in fiscal year 2025 and 2024 were recorded as a reduction to Selling, general and administrative expenses. The Company recorded approximately $10.3 million and $14.2 million of insurance recoveries during the years ended December 31, 2025 and 2024, respectively. There were no insurance recoveries during the year ended December 31, 2023. Insurance recovery receivable was $1.8 million and $4.0 million as of December 31, 2025 and December 31, 2024, respectively.

Interest Expense

Interest expense included the amortization of deferred financing costs and debt discount incurred by the Company in connection with the issuance of $402.5 million of 0.625% Convertible Senior Notes which were due and paid in 2023 (see Note 17, Interest Expense). The Company amortized deferred financing costs and debt discounts over the term of the debt, using the effective interest method. Interest expense also includes stated interest in connection with the Company's debt instruments.

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Notes to Consolidated Financial Statements (Continued)

2. Summary of Significant Accounting Policies (Continued)

Income Taxes

The Company utilizes the asset and liability method of accounting for income taxes. Under this method, deferred tax assets and deferred tax liabilities are determined based on differences between their financial reporting and tax reporting bases of assets and liabilities and are measured using enacted tax rates and laws that are expected to be in effect when the differences are expected to reverse. When appropriate, valuation allowances are established to reduce deferred tax assets to the amounts expected to be realized.

The Company accounts for uncertain tax positions in its consolidated financial statements when it is more-likely-than-not that the position will be sustained upon examination by the tax authorities. Such tax positions are initially and subsequently estimated as the largest amount of the tax benefit that has a greater than 50% likelihood of being realized upon ultimate settlement with the tax authorities, assuming full knowledge of the position and relevant facts.

The Company's policy is to recognize any interest and penalties related to income taxes as Income tax expense in the relevant period.

Recently Issued Accounting Pronouncements

Accounting Pronouncements Adopted

ASU 2023-09, Improvements to Income Tax Disclosures (Topic 740) - On December 14, 2023, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2023-09, Improvements to Income Tax Disclosures (ASU 2023-09). ASU 2023-09 amends ASC 740, Income Taxes, to expand income tax disclosures and requires that the Company disclose (i) the income tax rate reconciliation using both percentages and reporting currency amounts; (ii) specific categories within the income tax rate reconciliation; (iii) additional information for reconciling items that meet a quantitative threshold; (iv) the composition of state and local income taxes by jurisdiction; (v) pretax income (loss) from continuing operations disaggregated by jurisdiction and (vi) the amount of income taxes paid disaggregated by jurisdiction. The Company adopted ASU 2023-09 for the year ended December 31, 2025, on a prospective basis. See Note 12, Income Tax Expense (Benefit).

Accounting Pronouncements Not Yet Adopted

ASU 2024-03, Disaggregation of Income Statement Expenses (Topic 220) - The new standard, issued in November 2024, requires additional disclosure in tabular format, about the nature of specific types of expense captions presented on the face of the income statement as well as disclosures about selling expenses. The new standard does not change the requirements for the presentation of expenses on the face of the income statement. The standard is effective with annual periods beginning after December 15, 2026. Early adoption and retrospective application are permitted. The Company plans to adopt the guidance for the fiscal year ending December 31, 2027. We expect ASU 2024-03 to require additional disclosures in the notes to our consolidated financial statements. The Company is currently evaluating the effects the adoption of this guidance will have on the consolidated financial statements.

ASU 2025-06, Intangibles-Goodwill and Other-Internal-Use Software (Subtopic 350-40) - Targeted Improvements to the Accounting for Internal-Use Software (Topic 350) - The new standard, issued in September 2025, modernizes the accounting for internal-use software. ASU 2025-06 removes all references to software development stages and requires capitalization of software costs when management has committed to the software project and it is probable the software will be completed and perform its intended use. The Company plans to adopt the guidance for the fiscal year ending December 31, 2028. The Company is currently evaluating the method of its adoption of ASU 2025-06, and the effects the adoption of this guidance will have on the consolidated financial statements.

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Notes to Consolidated Financial Statements (Continued)

2. Summary of Significant Accounting Policies (Continued)

ASU 2025-11, Interim Reporting - Narrow-Scope Improvements (Topic 270) - The new standard, issued in December 2025, clarifies the interim reporting requirements by improving navigability of Topic 270 and more clearly specifies what disclosures are required in an interim reporting period. It is not intended to significantly change interim reporting or expand or reduce interim disclosure requirements. The standard is effective for interim reporting periods in fiscal years beginning after December 15, 2027. Early adoption is permitted. The Company plans to adopt the guidance for the fiscal year ending December 31, 2028. The Company is currently evaluating the effects the adoption of this guidance will have on the consolidated financial statements.

3. Sage Acquisition

On July 31, 2025 (the Sage Closing Date), the Company completed its acquisition of all the outstanding equity of Sage Therapeutics, Inc. pursuant to the Merger Agreement dated June 13, 2025 (the Sage Acquisition). Under the terms of the Merger Agreement, the Company commenced a tender offer to acquire all outstanding shares of Sage, par value $0.0001 per share (the Shares and each, a Share), at an offer price of (i) $8.50 per share in cash, less any applicable withholding taxes and without interest (the Cash Amount; an aggregate of approximately $561 million paid as of the acquisition date), plus (ii) one contingent value right per Share (the CVR; an aggregate of approximately $234 million, subject to the achievement of specific contingencies), which represents the right to receive up to $3.50, which is governed by the terms of a contingent value rights agreement entered into between the Company and CVR agent (the Sage CVR Agreement), in cash, less any applicable withholding taxes and without interest. The transaction provides Supernus with the right to develop and market ZURZUVAE® (zuranolone) capsules, the first and only FDA approved oral medicine indicated for the treatment of adults with postpartum depression, and a late-stage product candidate. For the year ended December 31, 2025, the Company incurred transaction costs of approximately $10.0 million to complete the acquisition, which were included in Selling, general and administrative expense in the consolidated statements of earnings (loss).

Contingent payments of up to $234 million are due to the sellers upon the achievement of certain milestones related to the development and commercial sale of ZURZUVAE. In connection therewith, the Company recorded a contingent consideration liability of $11.4 million as of the date of acquisition to reflect the estimated fair value of the contingent consideration. The estimated fair value of the contingent consideration was determined using a market participant approach with both implied fair value from the stock price combined with a Monte Carlo simulation for the sales-based milestones, and income approach for the other milestones. The key assumptions considered include the estimated amount and timing of projected revenues, probability of milestone achievement, volatility, implied market value at acquisition date, estimated discount rates, and risk-free interest rate. In each reporting period after the acquisition, the Company will revalue the contingent consideration liability and will record increases or decreases in the fair value of the liability in its consolidated statements of earnings (loss). Changes in fair value will result from changes in actual and projected milestone achievement, as well as changes to forecasts. The inputs and assumptions may not be observable in the market, but reflect the assumptions the Company believes would be made by a market participant. The possible outcomes for the contingent consideration range from $0 to $234 million on an undiscounted basis. See Note 7, Contingent Consideration, for further discussion.

In connection with the acquisition, the vesting of certain outstanding Sage stock options, restricted stock units, and performance stock units were accelerated upon closing of the acquisition and replaced with the right to receive one CVR per share. The purchase price for Sage includes $4.1 million related to Sage awards where vesting was accelerated in connection with the acquisition. The Company recognized compensation expense of $25.0 million in the post-combination period for the year ended December 31, 2025 related to awards that were accelerated to vest upon closing of the acquisition and for the portion of potential CVR payments to former Sage employees which are considered probable under the employee compensation accounting model. The Company will continue to evaluate whether the remaining portion of potential CVR payments to former Sage employees are considered probable under the employee compensation accounting model, and will recognize compensation expense if and when they become probable. See Note 10, Share-based Payments, for further discussion.

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Notes to Consolidated Financial Statements (Continued)

3. Sage Acquisition (Continued)

The acquisition is being accounted for as a business combination under the acquisition method of accounting, in accordance with ASC 805, Business Combinations. The excess of the purchase price over the fair value of the net assets acquired was recorded as goodwill. The estimated fair values of the assets acquired and liabilities assumed, including goodwill, have been included in the Company's consolidated financial statements since the Sage Closing Date.

The Company's accounting for this acquisition is preliminary, and fair value estimates for the assets acquired and liabilities assumed and the Company's estimates and assumptions are subject to change as the Company obtains additional information for its estimates during the measurement period. During the measurement period, if the Company obtains new information regarding facts and circumstances that existed as of the Sage Closing Date that, if known, would have resulted in revised estimated values of those assets or liabilities, the Company will accordingly revise its estimates of fair values and purchase price allocation. The effect of measurement period adjustments on the estimated fair value elements will be reflected as if the adjustments had been made as of the Sage Closing Date. The impact of all changes that do not qualify as measurement period adjustments will be included in current period earnings.

The Company expects to finalize its purchase price allocation within one year of the Sage Closing Date. In addition, the Company continues to analyze and assess relevant information necessary to determine, recognize and record at fair value the assets acquired and liabilities assumed in the following areas: inventory, prepaid and other assets, intangible assets, tax assets and liabilities, and certain existing or potential reserves, including those for legal or contract-related matters. The activities the Company is currently undertaking, include but are not limited to the following: review of acquired contracts and other contract-related and legal matters; review and evaluation of the accounting policies, tax positions, and other tax-related matters. Further, the Company is in the process of obtaining input from third party valuation firms with respect to the fair value of the acquired intangible assets and inventory, and other information necessary to record and measure the assets acquired and liabilities assumed. Accordingly, the preliminary recognition and measurement of assets acquired and liabilities assumed as of the Sage Closing Date are subject to change.

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Supernus Pharmaceuticals, Inc.

Notes to Consolidated Financial Statements (Continued)

3. Sage Acquisition (Continued)

The following preliminary purchase price allocation table presents the Company's preliminary estimates of the fair value of assets acquired and liabilities assumed as of the Sage Closing Date and subsequent measurement period adjustments recorded (unaudited, dollars in thousands):

As Initially Reported Measurement Period Adjustments (1) As Adjusted

Accounts payable and accrued liabilities 44,232 — 44,232

Cash consideration paid for Sage's common stock $ 533,667 — $ 533,667

Fair value of contingent consideration 11,448 — 11,448