Arrowhead Pharmaceuticals, Inc. and its subsidiaries (referred to herein collectively as the “Company”) are primarily engaged in developing medicines that treat intractable diseases by silencing the genes that cause them. Using a broad portfolio of RNA chemistries and efficient modes of delivery, the Company’s therapies trigger the RNA interference mechanism to induce rapid, deep and durable knockdown of target genes. RNA interference (“RNAi”) is a mechanism present in living cells that inhibits the expression of a specific gene, thereby affecting the production of a specific protein. The Company’s RNAi-based therapeutics may leverage this natural pathway of gene silencing to target and shut down specific disease-causing genes.

REDEMPLO® (plozasiran) is approved by the U.S. Food and Drug Administration (“FDA”) as an adjunct to diet to reduce triglycerides for adults with Familial Chylomicronemia Syndrome (“FCS”). REDEMPLO is also approved by the Chinese National Medical Products Administration (NMPA). In addition, Health Canada has issued a Notice of Compliance (NOC) authorizing REDEMPLO™ (plozasiran) as an adjunct to diet to reduce triglycerides in adults with FCS for whom standard triglyceride lowering therapies have been inadequate. REDEMPLO is a small interfering RNA (“siRNA”) therapeutic designed to suppress the production of apolipoprotein C-III (APOC3), a protein produced in the liver that raises triglyceride levels by slowing their breakdown and clearance. By targeting the APOC3 gene with sustained silencing, REDEMPLO delivers significant reductions in triglyceride levels. REDEMPLO is the first and only FDA-approved siRNA treatment studied in both genetically confirmed and clinically diagnosed patients living with FCS.


Therapeutic Area	Name	Stage	Product Rights
Cardiometabolic	plozasiran	Phase 3	Arrowhead(1)
	zodasiran	Phase 3	Arrowhead
	olpasiran	Phase 3	Amgen
	GSK4532990	Phase 2b	GSK
	ARO-PNPLA3	Phase 1	Arrowhead
	ARO-INHBE	Phase 1/2a	Arrowhead
	ARO-ALK7	Phase 1/2a	Arrowhead
	ARO-DIMER-PA	Phase 1/2a	Arrowhead
Pulmonary	ARO-RAGE	Phase 1/2a	Arrowhead
	SRP-1002 (ARO-MMP7)	Phase 1/2a	Sarepta
Liver	fazirsiran	Phase 3	Takeda and Arrowhead
	daplusiran/tomligisiran	Phase 2	GSK
Neuromuscular	SRP-1001 (ARO-DUX4)	Phase 1/2a	Sarepta
	SRP-1003 (ARO-DM1)	Phase 1/2a	Sarepta
	SRP-1004 (ARO-ATXN2)	Phase 1/2a	Sarepta
	SRP-1005 (ARO-HTT)	Phase 1	Sarepta
	ARO-MAPT	Phase 1/2a	Arrowhead
	ARO-SNCA	Pre-clinical	Novartis
Other	ARO-C3	Phase 1/2a	Arrowhead
	ARO-CFB	Phase 1/2a	Arrowhead

The Company operates lab facilities in California and Wisconsin, where its research and development activities, including the development of RNAi therapeutics, take place. The Company also operates an active pharmaceutical ingredient manufacturing and supporting laboratory facility in Verona, Wisconsin. The Company’s principal executive offices are located in Pasadena, California.

During the first quarter of fiscal 2026, the Company continued to develop and advance its pipeline and partnered candidates. The following is a summary of select significant developments affecting our business that have occurred since the filing of our Annual Report on Form 10-K for the fiscal year ended September 30, 2025:

•Filed a request for regulatory clearance to initiate a Phase 1/2a clinical trial of ARO-DIMER-PA, the Company’s investigational RNAi therapeutic being developed as a potential treatment for atherosclerotic cardiovascular disease (ASCVD) due to mixed hyperlipidemia. ARO-DIMER-PA is designed to silence expression of the proprotein convertase subtilisin kexin 9 (PCSK9) and apolipoprotein C3 (APOC3) genes. This represents an important step forward for the RNAi field as it is the first clinical candidate to target two genes simultaneously in one molecule, enabled by Arrowhead’s innovative and proprietary TRiM platform.;

•On November 20, 2025, the Company earned a $200.0 million milestone payment from Sarepta Therapeutics, Inc., which was triggered on November 20, 2025, when the Company reached the second of two prespecified enrollment targets and subsequent authorization to dose escalate in a Phase 1/2 clinical study of ARO-DM1, an investigational RNAi therapeutic for the treatment of type 1 myotonic dystrophy (DM1);

•Initiated and dosed the first subjects in a Phase 1/2a clinical trial of ARO-MAPT, the Company’s investigational RNAi therapeutic being developed as a potential treatment for tauopathies including Alzheimer’s disease, a progressive neurodegenerative disease characterized by cognitive and functional decline;

•Announced that the FDA has granted Breakthrough Therapy designation to investigational plozasiran as an adjunct to diet to reduce triglyceride (TG) levels in adults with severe hypertriglyceridemia (SHTG) (TG levels greater than or equal to 500 mg/dL);

•The FDA approved the Company's New Drug Application (NDA) for REDEMPLO injection for Familial Chylomicronemia Syndrome (FCS), on November 18, 2025. This approval was supported by clinical data from the Phase 3 PALISADE study, a randomized, double-blind, placebo-controlled trial in adults with clinically diagnosed or genetically confirmed FCS. The PALISADE study met its primary endpoint and all multiplicity-controlled key secondary endpoints, including demonstrating significant reductions in triglycerides and APOC3. In PALISADE, 25 mg REDEMPLO achieved deep and durable reductions in triglycerides, with a median change from baseline of -80% versus -17% in the pooled placebo group, and a lower numerical incidence of acute pancreatitis compared with placebo; and

•Entered into a global licensing and collaboration agreement with Novartis Pharma AG ("Novartis") on August 29, 2025, which closed on October 17, 2025. Closing of the transaction was subject to the expiration or termination of the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976 and other customary conditions. Upon closing, the Company received $200.0 million as an upfront payment on October 23, 2025. Additionally, the Company is eligible to receive up to $2.0 billion in potential milestone payments plus royalties on commercial sales.

•Announced interim results from two Phase 1/2a clinical trials of ARO-INHBE and ARO-ALK7, the Company’s investigational RNAi therapeutics being developed as potential treatments for obesity, showing for patients enrolled in the study that's:

◦ARO-INHBE in combination with tirzepatide, a GLP-1/GIP receptor co-agonist, nearly doubled weight loss at week 16 and roughly tripled reductions in visceral fat, total fat, and liver fat versus tirzepatide alone in obese patients with type 2 diabetes mellitus at those same endpoints at week 12.

◦ARO-ALK7, the first RNAi-therapeutic to show adipocyte gene target silencing in a clinical trial, achieved dose dependent reductions in adipose ALK7 mRNA with a mean reduction of -88% at the 200 mg dose at week 8 with a maximum reduction of -94%.

The interim Consolidated Financial Statements include the accounts of Arrowhead Pharmaceuticals, Inc. and its subsidiaries (wholly-owned subsidiaries and a variable interest entity for which the Company is the primary beneficiary). Subsidiaries refer to Arrowhead Madison, Inc., Arrowhead Australia Pty Ltd., Arrowhead Pharmaceuticals Ireland Limited, Arrowhead Pharmaceuticals NZ Limited and Visirna Therapeutics, Inc. (“Visirna”). For subsidiaries in which the Company owns or is exposed to less than 100% of the economics, the Company records net loss attributable to noncontrolling interests in its consolidated statements of operations equal to the percentage of the economic or ownership interests retained in such entity by the respective noncontrolling party

The interim Consolidated Financial Statements have been prepared in conformity with U.S. generally accepted accounting principles (“GAAP”). The financial data of the Company included herein are unaudited. In the opinion of management, all material adjustments of a normal recurring nature have been made to present fairly the Company’s financial position as of December 31, 2025 and the results of operations and cash flows for the periods presented. All intercompany transactions and balances have been eliminated. Certain prior period amounts have been reclassified to conform with the current period presentation.

Certain financial information that is normally included in annual financial statements prepared in accordance with GAAP, but that is not required for interim reporting purposes, has been omitted from the accompanying interim consolidated financial statements and related notes. Readers are urged to review the Company’s Annual Report on Form 10-K for the fiscal year ended September 30, 2025 for more complete descriptions and discussions. Operating results and cash flows for the three months ended December 31, 2025 are not necessarily indicative of the results that may be expected for the fiscal year ending September 30, 2026.

The Company operates as a single segment as the chief operating decision maker (“CODM”), reviews operating results on an aggregate basis and manages the operations as a single operating segment. Refer to Note 15, Segment Information, for further details on the segment information.

The Company’s primary sources of financing have been through the sale of its equity securities, credit facility, revenue from its licensing and collaboration agreements and the sale of certain future royalties. Research and development activities have required significant investment since the Company’s inception and are expected to continue to require significant cash expenditure in the future, particularly as the Company’s pipeline of drug candidates and its headcount have both expanded. Additionally, significant investment will be required as a growing commercial-stage Company and as the Company’s pipeline matures into later stage clinical trials.

As of December 31, 2025, the Company had $201.6 million in cash, cash equivalents and restricted cash ($1.9 million in restricted cash) and $715.0 million in available-for-sale securities to fund operations. During the three months ended December 31, 2025, the Company’s cash, cash equivalents and restricted cash and investments balance decreased by $2.8 million, which was primarily due to the $66.7 million payment on its credit facility and ongoing expenses related to the Company’s research and development programs, which were partially offset by a $200.0 million received as an upfront payment under the Novartis agreement, $46.8 million in net proceeds from the issuance of common stock under the Company's at-the-market equity offering program with Jefferies LLC and $9.7 million interest income earned on investments.

In total, the Company is eligible to receive up to $15.3 billion in additional developmental, regulatory and sales milestones based on programs that have been partnered, and may receive various royalties on net sales from its licensing and collaboration agreements, subject to the terms and conditions of those agreements.

In January 2025, the Financial Accounting Standards Board (“FASB”) issued Accounting Standard Update (“ASU”) 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses, in November 2024, and ASU 2025-01, Clarifying the Effective Date. These updates require entities to provide disaggregated disclosures of income statement expenses. The ASUs do not affect the expense captions presented on the face of the income statement but instead require the disaggregation of certain expense

captions into specified categories within the footnotes to the financial statements. The ASUs will become effective for the Company beginning October 1, 2027, and the Company is currently evaluating the impact on its consolidated financial statements and related disclosures.