Business Organization	6 Months Ended
Jun. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business Organization	Business Organization Supernus Pharmaceuticals, Inc. (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 epilepsy, migraine, attention-deficit hyperactivity disorder (ADHD), hypomobility in Parkinson’s Disease (PD), cervical dystonia, and chronic sialorrhea. The Company is also developing a broad range of novel CNS product candidates including new potential treatments for ADHD, hypomobility in PD, epilepsy, depression, and rare CNS disorders. Commercial Products •Trokendi XR® (topiramate) is the first once-daily extended release topiramate product indicated for the treatment of epilepsy in the United States (U.S.) market. It is also indicated for the prophylaxis of migraine headache. •Oxtellar XR® (oxcarbazepine) is indicated as therapy for partial onset seizures in adults and children 6 years to 17 years of age and is the first once-daily extended-release oxcarbazepine product indicated for the treatment of epilepsy in the U.S. •QelbreeTM (viloxazine extended-release capsules) is a novel non-stimulant product indicated for the treatment of ADHD in pediatric patients 6 to 17 years of age. •APOKYN® (apomorphine hydrochloride injection) is a product indicated for the acute, intermittent treatment of hypomobility or "off" episodes ("end-of-dose wearing off" and unpredictable "on-off" episodes) in patients with advanced PD. •MYOBLOC® (rimabotulinumtoxinB) is a product indicated for the treatment of cervical dystonia and sialorrhea in adults, and it is the only Type B toxin available on the market. •XADAGO® (safinamide) is a once-daily product indicated as adjunctive treatment to levodopa/carbidopa in patients with PD experiencing "off" episodes. Product Candidates •SPN-812 (viloxazine hydrochloride) is a novel non-stimulant product candidate for the treatment of ADHD in adult patients. •SPN-830 (Apomorphine Infusion Pump) is a late-stage drug/device combination product candidate for the continuous prevention of "off" episodes in PD. •SPN-817 is a novel product candidate for the treatment of severe epilepsy. •SPN-820 is a first-in-class product candidate for treatment resistant depression (TRD). It is an orally active small molecule that directly activates brain mechanistic target of rapamycin complex 1 (mTORC1). In April 2021, the U.S. Food and Drug Administration (FDA) approved Qelbree (SPN-812) for the treatment of ADHD in pediatric patients 6 to 17 years of age. In May 2021, the Company launched Qelbree in the U.S. On April 28, 2020, the Company entered into a Sale and Purchase Agreement with US WorldMeds Partners, LLC to acquire the CNS portfolio of USWM Enterprises, LLC (USWM Enterprises) (USWM Acquisition). With the acquisition, completed on June 9, 2020, the Company added three established commercial products, APOKYN, XADAGO, and MYOBLOC, and a product candidate in late-stage development, SPN-830, to its portfolio. Refer to Note 3, USWM Acquisition, for further discussion on the USWM Acquisition. On April 21, 2020, the Company entered into a Development and Option Agreement (Development Agreement) with Navitor Pharmaceuticals, Inc. (Navitor Inc.) and also acquired an ownership position in Navitor Inc. Under the terms of the Development Agreement, the Company and Navitor Inc. will jointly conduct a Phase II clinical program for NV-5138 (SPN-820) in TRD. In March 2021, Navitor Inc. underwent a legal restructuring whereby Navitor Inc. became a wholly owned subsidiary of a newly formed limited liability company, Navitor Pharmaceuticals, LLC (Navitor LLC). Refer to Note 5, Investments, for further discussion on the Navitor Development Agreement and equity investment. COVID-19 Impact While the impact of the ongoing COVID-19 pandemic did not have a material adverse effect on the Company's financial position or results of operations for the three and six months ended June 30, 2021, the Company continues to closely monitor the events and circumstances surrounding the COVID-19 pandemic and its impact on all aspects of our business operations. Since the situation surrounding the COVID-19 pandemic remains fluid and the duration uncertain, the long-term nature and extent of the impacts of the pandemic on the Company's business operations and financial position cannot be reasonably estimated at this time.

Supernus Pharmaceuticals, Inc. (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 epilepsy, migraine, attention-deficit hyperactivity disorder (ADHD), hypomobility in Parkinson’s Disease (PD), cervical dystonia, and chronic sialorrhea. The Company is also developing a broad range of novel CNS product candidates including new potential treatments for ADHD, hypomobility in PD, epilepsy, depression, and rare CNS disorders.

•Trokendi XR® (topiramate) is the first once-daily extended release topiramate product indicated for the treatment of epilepsy in the United States (U.S.) market. It is also indicated for the prophylaxis of migraine headache.

•Oxtellar XR® (oxcarbazepine) is indicated as therapy for partial onset seizures in adults and children 6 years to 17 years of age and is the first once-daily extended-release oxcarbazepine product indicated for the treatment of epilepsy in the U.S.

•QelbreeTM (viloxazine extended-release capsules) is a novel non-stimulant product indicated for the treatment of ADHD in pediatric patients 6 to 17 years of age.

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

•MYOBLOC® (rimabotulinumtoxinB) is a product indicated for the treatment of cervical dystonia and sialorrhea in adults, and it is the only Type B toxin available on the market.

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

•SPN-812 (viloxazine hydrochloride) is a novel non-stimulant product candidate for the treatment of ADHD in adult patients.

•SPN-830 (Apomorphine Infusion Pump) is a late-stage drug/device combination product candidate for the continuous prevention of "off" episodes in PD.

•SPN-820 is a first-in-class product candidate for treatment resistant depression (TRD). It is an orally active small molecule that directly activates brain mechanistic target of rapamycin complex 1 (mTORC1).

In April 2021, the U.S. Food and Drug Administration (FDA) approved Qelbree (SPN-812) for the treatment of ADHD in pediatric patients 6 to 17 years of age. In May 2021, the Company launched Qelbree in the U.S.

On April 28, 2020, the Company entered into a Sale and Purchase Agreement with US WorldMeds Partners, LLC to acquire the CNS portfolio of USWM Enterprises, LLC (USWM Enterprises) (USWM Acquisition). With the acquisition, completed on June 9, 2020, the Company added three established commercial products, APOKYN, XADAGO, and MYOBLOC, and a product candidate in late-stage development, SPN-830, to its portfolio. Refer to Note 3, USWM Acquisition, for further discussion on the USWM Acquisition.

On April 21, 2020, the Company entered into a Development and Option Agreement (Development Agreement) with Navitor Pharmaceuticals, Inc. (Navitor Inc.) and also acquired an ownership position in Navitor Inc. Under the terms of the Development Agreement, the Company and Navitor Inc. will jointly conduct a Phase II clinical program for NV-5138 (SPN-820) in TRD. In March 2021, Navitor Inc. underwent a legal restructuring whereby Navitor Inc. became a wholly owned subsidiary of

a newly formed limited liability company, Navitor Pharmaceuticals, LLC (Navitor LLC). Refer to Note 5, Investments, for further discussion on the Navitor Development Agreement and equity investment.