Business/Financial Results (Form 8-K)

Filed by: Supernus Pharmaceuticals, Inc.

Pursuant to Rule 425 under the Securities Act of 1933

and deemed filed pursuant to Rule 14a-12 under the Securities Exchange Act of 1934

Subject Company: Supernus Pharmaceuticals, Inc.

Commission File No.: 001-35518

Date: August 3, 2026

Supernus Announces Second Quarter 2026 Financial Results

•Total revenues were $219.1 million in the second quarter 2026, a 32% increase compared to same period last year.

•Combined revenues of the Company's four growth products increased to $175.7 million in the second quarter 2026, representing an increase of 52% compared to the same period last year. This strong growth was driven by an increase in net sales of Qelbree® , GOCOVRI®, ZURZUVAE®, and ONAPGO™.

•Regulatory submission to the FDA for second supplier for ONAPGO remains on-track for third quarter 2026, with potential approval by mid-year 2027.

•The Company is raising its full year 2026 financial guidance.

•Announced today agreement to merge with Indivior Pharmaceuticals, Inc. (Indivior) creating a diversified CNS biopharmaceutical company with significant scale.

ROCKVILLE, Md., August 3, 2026 - Supernus Pharmaceuticals, Inc. (Nasdaq: SUPN), a biopharmaceutical company focused on developing and commercializing products for the treatment of central nervous system (CNS) diseases, today announced financial results for the second quarter 2026 and associated Company developments.

"Our first-half 2026 results reflect the continued strength and sustained momentum of our growth products and continued execution on our commercial strategy," said Jack Khattar, President and CEO of Supernus. "As we look to the remainder of the year, we remain focused on disciplined execution and prudent capital allocation, and we believe we are well positioned to build on this momentum."

"We are excited about the future of Supernus, even more so following the recent agreement to merge with Indivior Pharmaceuticals, Inc. The combination of these two businesses will form a well-positioned CNS company with a unique profile of scale, growth, and flexibility to pursue additional business development opportunities."

Commercial Highlights

•ONAPGO net product sales were $13.5 million in the second quarter of 2026. Since the launch in April 2025, and through the end of July 2026, approximately 2,600 enrollment forms have been submitted by approximately 720 prescribers. The Company remains on-track to submit a regulatory filing to the U.S. Food and Drug Administration (FDA) for a second supplier for ONAPGO in the third quarter of 2026, with potential FDA approval by mid-year 2027.

•Collaboration revenue from ZURZUVAE was $35.4 million in the second quarter of 2026. Collaboration revenue represents 50% of the net revenues for ZURZUVAE recorded by Biogen Inc. Second quarter 2026 U.S sales of ZURZUVAE, as reported by Biogen Inc., increased approximately 53% compared to the same period in 2025. The total number of prescriptions for ZURZUVAE increased by 62% in the second quarter of 2026 compared to the same period last year.

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•Net sales of Qelbree increased 15% to $89.2 million in the second quarter of 2026, compared to the same period in 2025, driven primarily by volume growth. Total IQVIA prescriptions(6) for Qelbree were 264,545 for the second quarter 2026, representing an increase of 17% compared to the same period last year. Prescription growth in the adult and pediatric populations was 25% and 14%, respectively.

•Net sales of GOCOVRI increased 2% to $37.6 million in the second quarter of 2026, compared to the same period in 2025. Total number of prescriptions grew by 9% in the second quarter of 2026 compared to the same period last year.

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 Phase 2b multi-center, randomized, double-blind, placebo-controlled trial in approximately 200 adults with major depressive disorder (MDD). The study will examine the safety and tolerability of SPN-820 2400mg 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.

Financial Highlights

This section includes information on non-GAAP financial measures. See "Non-GAAP Financial Information" section for information on non-GAAP financial measures. In addition, a reconciliation of applicable GAAP to non-GAAP financial information is included at the end of this press release.

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Revenues

The following table provides information regarding total revenues (dollars in millions):

			Three Months Ended June 30,																		Six Months Ended June 30,
			2026						2025						Change %						2026						2025						Change %
			(unaudited)																		(unaudited)
Net product sales
Qelbree			$	89.2					$	77.6					15%						$	167.1					$	142.3					17%
GOCOVRI			37.6						36.7						2%						72.8						67.4						8%
ONAPGO			13.5						1.6						745%						21.9						1.6						1267%
Trokendi XR®			8.4						11.2						(25)%						17.9						24.0						(25)%
Oxtellar XR®			8.8						11.6						(25)%						16.2						21.8						(26)%
APOKYN®			6.3						12.8						(51)%						14.0						27.8						(49)%
Other(2)			1.9						6.5						(71)%						6.6						15.1						(57)%
Total net product sales			165.7						158.0						5%						316.5						300.0						5%
Collaboration revenue (ZURZUVAE) (3)			35.4						-						100%						63.0						-						100%
Total revenues from commercial products (Non-GAAP) (1) (4)			201.1						158.0						27%						379.5						300.0						27%
Royalty, licensing and other revenues(5)			18.0						7.5						141%						47.3						15.3						209%
Total revenues			$	219.1					$	165.5					32%						$	426.8					$	315.3					35%

Total revenues from commercial products (non-GAAP)(1)(4) represent revenues from our product sales to customers and through our collaboration agreement with Biogen.

Other Financial Highlights

•Operating loss was $58.0 million for the second quarter of 2026, compared to an operating earnings of $12.1 for the same period in 2025. The change was primarily due to a non-cash $54.9 million intangible asset impairment charge related to APOKYN in the second quarter of 2026, an increase in selling, general, and administrative expenses associated with the collaboration agreement with Biogen Inc., partially offset by higher revenues.

•Adjusted operating earnings (non-GAAP)(1) were $31.2 million in the second quarter of 2026, compared to $40.9 million for the same period in 2025.

•Net loss and diluted loss per share were $58.4 million and $1.01 for the second quarter of 2026, respectively, compared to net earnings and diluted earnings per share of $22.5 million and $0.40 for the same period in 2025.

•Cash, cash equivalents, and current marketable securities were approximately $372.1 million as of June 30, 2026, compared to $308.7 million as of December 31, 2025. This increase was primarily due to cash generated from operations.

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Full Year 2026 Financial Guidance

The Company is raising its full year 2026 financial guidance as set forth below (dollars in millions):

						Current Guidance (as of August 4, 2026)						Previous Guidance (as of February 24, 2026)
Total revenues include the following(7): ◦ONAPGO net sales of $55 million - $70 million ◦Trokendi XR and Oxtellar XR net sales of $50 million - $60 million						$860 - $890						$840 - $870
Combined R&D and SG&A expenses						$630 - $660						$620 - $650
Operating earnings (loss)						$(20) - $(50)						$0 - $30
Adjusted operating earnings (non-GAAP)(1)						$150 - $180						$140 - $170

Non-GAAP Financial Information