0001628280-24-036104 | 10-Q | XBRL Viewer | Arrowhead Pharmaceuticals INC

Print Document

Balance Sheet Accounts

9 Months Ended

Jun. 30, 2024

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Balance Sheet Accounts

BALANCE SHEET ACCOUNTS

Property, Plant and Equipment

The following table summarizes the Company’s major classes of property, plant and equipment:


	June 30, 2024		September 30, 2023
	(in thousands)
Land	$	2,996	$	2,996
Building	75,868		—
Research equipment	64,207		56,509
Furniture	5,593		1,540
Computers and software	976		700
Leasehold improvements	104,396		103,813
Construction in progress	175,778		166,655
	429,814		332,213
Less: Accumulated depreciation and amortization	(53,903)		(41,951)
Property, plant and equipment, net	$	375,911	$	290,262

Depreciation and amortization expense for property, plant and equipment for the three months ended June 30, 2024 and 2023 was $4.4 million and $2.9 million, respectively. Depreciation and amortization expense for property and equipment for the nine months ended June 30, 2024 and 2023 was $12.3 million and $7.4 million, respectively.

During the first quarter of fiscal 2024, the Company completed the build out of one of its laboratory and office facilities in Verona, Wisconsin, which resulted in the reclassification of $75.9 million from construction in progress to building as of June 30, 2024. Further, the Company commenced depreciation on the newly completed facility over a 39-year period.

Accrued Expenses

Accrued expenses consist of the following:


	June 30, 2024		September 30, 2023
	(in thousands)
Accrued R&D expenses	$	17,911	$	16,125
Accrued R&D expenses; co-development	21,280		5,895
Accrued capital expenditures	6,909		14,044
Other	1,799		3,699
Total accrued expenses	$	47,899	$	39,763

Net Loss Per Share

9 Months Ended

Jun. 30, 2024

Earnings Per Share [Abstract]

Net Loss Per Share

NET LOSS PER SHARE

The following table presents the computation of basic and diluted net loss per share for the three and nine months ended June 30, 2024 and 2023.


	Three Months Ended June 30,				Nine Months Ended June 30,
	2024		2023		2024		2023
	(in thousands, except per share amounts)
Numerator:
Net loss attributable to Arrowhead Pharmaceuticals, Inc.	$	(170,793)	$	(102,946)	$	(428,957)	$	(95,596)

Denominator:
Weighted-average basic shares outstanding	124,199		107,004		118,260		106,597
Effect of dilutive securities	—		—		—		—
Weighted-average diluted shares outstanding	124,199		107,004		118,260		106,597

Basic net loss per share	$	(1.38)	$	(0.96)	$	(3.63)	$	(0.90)
Diluted net loss per share	$	(1.38)	$	(0.96)	$	(3.63)	$	(0.90)

The following table sets forth the potentially dilutive securities that have been excluded from the calculation of diluted net loss per share because to include them would be anti-dilutive.


	Three Months Ended June 30,		Nine Months Ended June 30,
	2024	2023	2024	2023
	(in thousands)
Options	753	637	711	768
Restricted stock units	3,976	2,830	4,060	3,256
Total	4,729	3,467	4,771	4,024

Stock-Based Compensation - Summary of RSUs Activity (Details) - Restricted stock units	9 Months Ended
	Jun. 30, 2024 $ / shares shares
Number of RSUs
Beginning of period (in shares) \| shares	4,241,640
Granted (in shares) \| shares	1,876,825
Vested (in shares) \| shares	(927,766)
Forfeited (in shares) \| shares	(160,775)
End of period (in shares) \| shares	5,029,924
Weighted- Average Grant Date Fair Value Per Share
Beginning balance (in dollars per share) \| $ / shares	$ 58.43
Granted (in dollars per share) \| $ / shares	30.67
Vested (in dollars per share) \| $ / shares	53.16
Forfeited (in dollars per share) \| $ / shares	41.75
Ending balance (in dollars per share) \| $ / shares	$ 49.58

Collaboration and License Agreements - Visirna Therapeutics, Inc. (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Sep. 30, 2023
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue	$ 0	$ 15,825	$ 3,551	$ 224,638
Deferred revenue	0		0		$ 866
Visirna Therapeutics, Inc. \| Visirna License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue			100	$ 900
Contract assets	0		0
Deferred revenue	$ 0		$ 0

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 41
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-41

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 270
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482964/270-10-50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (ee)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

Reference 4: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

Reference 5: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 924
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 11.L)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479941/924-10-S99-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-5

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 30
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-30

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-42

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-22

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 40
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-40

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-22

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-4

+ Details

Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2024	Sep. 30, 2023
Current assets:
Cash, cash equivalents and restricted cash	$ 69,399	$ 110,891
Available-for-sale securities, at fair value	367,272	292,735
Prepaid expenses	9,207	8,813
Other current assets	4,184	4,033
Total current assets	450,062	416,472
Property, plant and equipment, net	375,911	290,262
Intangible assets, net	8,987	10,262
Right-of-use assets	44,339	45,297
Other assets	4,460	3,259
Total Assets	883,759	765,552
Current liabilities:
Accounts payable	26,550	35,866
Accrued expenses	47,899	39,763
Accrued payroll and benefits	15,795	17,963
Lease liabilities	6,053	10,563
Deferred revenue	0	866
Other liabilities	417	435
Total current liabilities	96,714	105,456
Long-term liabilities:
Lease liabilities, net of current portion	112,040	104,608
Liability related to the sale of future royalties	336,031	268,326
Total long-term liabilities	448,071	372,934
Commitments and contingencies (Note 7)
Noncontrolling interest and stockholders’ equity:
Common stock, $0.001 par value: Authorized 290,000 shares; issued and outstanding 124,227 and 107,312 shares	217	200
Additional paid-in capital	1,786,304	1,300,395
Accumulated other comprehensive loss	(987)	(3,222)
Accumulated deficit	(1,454,987)	(1,026,030)
Total Arrowhead Pharmaceuticals, Inc. stockholders’ equity	330,547	271,343
Noncontrolling interest	8,427	15,819
Total noncontrolling interest and stockholders’ equity	338,974	287,162
Total Liabilities, Noncontrolling Interest and Stockholders’ Equity	$ 883,759	$ 765,552

Liability Related to the Sale of Future Royalties - Activity (Details) - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Liability, Sale Of Future Royalties [Roll Forward]
Carrying value as of September 30, 2023	$ 268,326
Non-cash interest expense recognized	17,705	$ 13,064
Carrying value as of June 30, 2024	$ 336,031

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Pay vs Performance Disclosure
Net loss attributable to Arrowhead Pharmaceuticals, Inc.	$ (170,793)	$ (102,946)	$ (428,957)	$ (95,596)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483443/250-10-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483443/250-10-50-9

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 60
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476176/805-60-65-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 323
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (g)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478666/740-323-65-2

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(20))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(g)(1)(ii))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481687/323-10-50-3

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 28
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-28

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482765/220-10-50-6

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483443/250-10-50-3

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483443/250-10-50-1

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480175/815-40-65-1

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483443/250-10-50-8

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483443/250-10-50-11

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483443/250-10-50-11

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483443/250-10-50-4

Reference 17: http://www.xbrl.org/2003/role/exampleRef
-Topic 946
-SubTopic 830
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479168/946-830-55-10

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section 45
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479105/946-220-45-7

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(18))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1

Reference 20: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(9))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-09(1)(d))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-3

Reference 22: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(i))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1A

Reference 23: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(ii))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1A

Reference 24: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(iii)(A))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1A

Reference 25: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(iv))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1A

Reference 26: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(5))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1A

Reference 27: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(i))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1B

Reference 28: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iii)(A))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1B

Reference 29: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iii)(B))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1B

Reference 30: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iv))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1B

Reference 31: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(5))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1B

Reference 32: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 60B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482689/260-10-45-60B

Reference 33: http://www.xbrl.org/2003/role/disclosureRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483499/205-20-50-7

Reference 34: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 35: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-1A

Reference 36: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-1B

Reference 37: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(22))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1

+ Details

Investments

9 Months Ended

Jun. 30, 2024

Investments, Debt and Equity Securities [Abstract]

Investments

INVESTMENTS

The Company’s investments consisted of the following:


	As of June 30, 2024
	(in thousands)
	Adjusted Basis		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value


Available-for-sale securities	$	367,862	$	8	$	(598)	$	367,272

Total current investments	$	367,862	$	8	$	(598)	$	367,272


	As of September 30, 2023
	(in thousands)
	Adjusted Basis		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value


Available-for-sale securities	$	295,699	$	3	$	(2,967)	$	292,735

Total current investments	$	295,699	$	3	$	(2,967)	$	292,735

The Company has determined that the available-for-sale securities that were in an unrealized loss position did not have any credit loss impairment as of June 30, 2024 and 2023.

Organization and Significant Accounting Policies (Policies)	9 Months Ended
	Jun. 30, 2024
Accounting Policies [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements In December 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standard Update (“ASU”) 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, to improve its income tax disclosure requirements. Under the guidance, entities must annually (1) disclose specific categories in the rate reconciliation and (2) provide additional information for reconciling items that meet a quantitative threshold. This guidance will become effective for the Company beginning on October 1, 2025. The Company does not expect any material impact on its consolidated financial statements and related disclosures resulting from applying this ASU. In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures, which is intended to improve reportable segment disclosure requirements, primarily through additional disclosures about significant segment expenses. The guidance requires public companies with a single reportable segment to provide all disclosures required under ASC 280. In addition, the guidance requires public companies to include in interim reports all disclosures related to a reportable segment’s profit or loss and assets that are currently required in annual reports. The standard is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted. The amendments should be applied retrospectively to all prior periods presented in the financial statements. The Company does not expect any material impact on its consolidated financial statements and related disclosures resulting from applying this ASU.

Organization and Significant Accounting Policies

9 Months Ended

Jun. 30, 2024

Accounting Policies [Abstract]

Organization and Significant Accounting Policies

ORGANIZATION AND SIGNIFICANT ACCOUNTING POLICIES

General and Recent Developments

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.

The following table presents the Company’s current pipeline:


Therapeutic Area	Name	Stage	Product Rights
Cardiometabolic	plozasiran (ARO-APOC3)	Phase 3	Arrowhead
	zodasiran (ARO-ANG3)	Phase 2b	Arrowhead
	olpasiran	Phase 3	Amgen
Pulmonary	ARO-RAGE	Phase 1/2a	Arrowhead
	ARO-MUC5AC	Phase 1/2a	Arrowhead
	ARO-MMP7	Phase 1/2a	Arrowhead
Liver	GSK-4532990	Phase 2b	GSK
	fazirsiran	Phase 3	Takeda and Arrowhead
	daplusiran/tomligisiran (GSK5637608, formerly JNJ-3989)	Phase 2	GSK
	ARO-PNPLA3	Phase 1	Arrowhead
	ARO-C3	Phase 1/2a	Arrowhead
	ARO-CFB	Phase 1/2a	Arrowhead
Muscle	ARO-DUX4	Phase 1/2a	Arrowhead
	ARO-DM1	Phase 1/2a	Arrowhead
Central Nervous System (CNS)	Various	Pre-Clinical	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’s principal executive offices are located in Pasadena, California.

Thus far in fiscal 2024, the Company has continued to develop and advance its pipeline and partnered candidates. Several key recent developments include:

•Announced plans to advance investigational plozasiran into a Phase 3 cardiovascular outcomes trial called CAPITAN, which is designed to enroll patients with mixed hyperlipidemia and residual risk of atherosclerotic cardiovascular disease;

•Announced successful top-line results from the pivotal Phase 3 PALISADE study of investigational plozasiran in patients with familial chylomicronemia syndrome (FCS). The Company highlighted recent data for its cardiometabolic pipeline at its June 25, 2024, Cardiometabolic event;

•Presented preclinical data on ARO-INHBE for the treatment of obesity and metabolic diseases at the American Diabetes Association 84th Scientific Sessions. INHBE small interfering RNA (siRNA) administration resulted in multiple promising findings including: (1) 95% reduction in INHBE mRNA expression, (2) 19% suppression of body weight compared to saline controls, (3) 26% loss of fat mass, and (4) preservation of lean mass;

•Announced results from the Phase 2b double blind, randomized ARCHES-2 study of investigational zodasiran in patients with mixed hyperlipidemia;

•Announced that new interim clinical data on ARO-RAGE achieves high level of gene knockdown in patients with asthma;

•Completed enrollment in Amgen’s Phase 3 OCEAN(a) - outcome trial of olpasiran, triggering a $50.0 million milestone payment to the Company, which was paid in the third quarter of fiscal 2024;

•Presented final data from the double-blind treatment period of the Company’s Phase 2 SHASTA-2 study of investigational plozasiran in patients with severe Hypertriglyceridemia. Results from the SHASTA-2 study showed dramatic, consistent, and sustained reductions in Apolipoprotein C-III (APOC3) and triglycerides and improvement in multiple atherogenic lipoprotein levels;

•Announced an Expanded Access Program (“EAP”) to make investigational plozasiran available outside of a clinical trial for qualifying patients with FCS;

•Initiated a Phase 1/2a clinical trial of ARO-DM1, being developed as a potential treatment for type 1 myotonic dystrophy (DM1), the most common adult-onset muscular dystrophy;

•Filed an application for clearance to initiate a Phase 1/2a clinical trial of ARO-CFB, being developed as a potential treatment for complement mediated renal disease;

•Entered into an Amended and Restated License Agreement with GSK, pursuant to which GSK received a worldwide, exclusive license to develop and commercialize daplusiran/tomligisiran (GSK5637608, formerly JNJ-3989). Daplusiran/tomligisiran had previously been licensed to Janssen Pharmaceuticals, Inc. See Note 2.

Consolidation and Basis of Presentation

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., Visirna Therapeutics, Inc. (“Visirna”), and Arrowhead Australia Pty Ltd. 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 at June 30, 2024 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 year ended September 30, 2023 for more complete descriptions and discussions. Operating results and cash flows for the nine months ended June 30, 2024 are not necessarily indicative of the results that may be expected for the fiscal year ending September 30, 2024.

Liquidity

The Company’s primary sources of financing have been through the sale of its equity securities, revenue from its licensing and collaboration agreements and the sale of certain future royalties. Research and development activities have required significant capital 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 capital investment will be required as the Company’s pipeline matures into later stage clinical trials.

As of June 30, 2024, the Company had $69.4 million in cash, cash equivalents and restricted cash ($2.2 million in restricted cash) and $367.3 million in available-for-sale securities to fund operations. During the nine months ended June 30, 2024, the Company’s cash, cash equivalents and restricted cash and investments balance increased by $33.0 million which was primarily due to the net proceeds of $429.3 million from the underwritten offering in January 2024 discussed below, offset by ongoing expenses related to the Company’s research and development programs, general and administrative expenses and capital expenditures.

On January 2, 2024, the Company entered into an underwriting agreement with Jefferies LLC, BofA Securities, Inc.,

and Cowen and Company, LLC, as representatives of the several underwriters. The Company issued 15,790,000 shares of common stock at a price of $28.50 per share. The aggregate purchase price paid by investors was $450.0 million and the Company received net proceeds of $429.3 million after deducting advisory fees and offering expenses.

In total, the Company is eligible to receive up to $2.7 billion in developmental, regulatory and sales milestones, and may receive various royalties on net sales from its licensing and collaboration agreements, subject to the terms and conditions of those agreements. The revenue recognition for these collaboration agreements is discussed further in Note 2.

Summary of Significant Accounting Policies

There have been no changes to the significant accounting policies disclosed in the Company’s most recent Annual Report on Form 10-K for the fiscal year ended September 30, 2023.

Uncertainty in Income Taxes

The Company recorded an income tax benefit of $3.3 million and expense of $0.8 million for the nine months ended June 30, 2024 and 2023, respectively. The income tax benefit is primarily due to the discrete change in the Company’s uncertain tax positions related to the statute of limitation expiration.

Recent Accounting Pronouncements

In December 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standard Update (“ASU”) 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, to improve its income tax disclosure requirements. Under the guidance, entities must annually (1) disclose specific categories in the rate reconciliation and (2) provide additional information for reconciling items that meet a quantitative threshold. This guidance will become effective for the Company beginning on October 1, 2025. The Company does not expect any material impact on its consolidated financial statements and related disclosures resulting from applying this ASU.

In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures, which is intended to improve reportable segment disclosure requirements, primarily through additional disclosures about significant segment expenses. The guidance requires public companies with a single reportable segment to provide all disclosures required under ASC 280. In addition, the guidance requires public companies to include in interim reports all disclosures related to a reportable segment’s profit or loss and assets that are currently required in annual reports. The standard is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted. The amendments should be applied retrospectively to all prior periods presented in the financial statements. The Company does not expect any material impact on its consolidated financial statements and related disclosures resulting from applying this ASU.

Stock-Based Compensation - Summary of Granted and Outstanding Shares (Details) - shares	Jun. 30, 2024	Sep. 30, 2023
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of options outstanding (in shares)	2,012,497	2,263,477
Total (in shares)	7,042,421
Restricted stock units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based payment award (in shares)	5,029,924	4,241,640
2013 Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of options outstanding (in shares)	1,315,326
Total (in shares)	2,924,586
2013 Incentive Plan \| Restricted stock units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based payment award (in shares)	1,609,260
2021 Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of options outstanding (in shares)	32,151
Total (in shares)	2,836,177
2021 Incentive Plan \| Restricted stock units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based payment award (in shares)	2,804,026
Inducement Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of options outstanding (in shares)	665,020
Total (in shares)	1,281,658
Inducement Awards \| Restricted stock units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based payment award (in shares)	616,638

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 35
-Paragraph 1D
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480483/718-10-35-1D

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 35
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480483/718-10-35-3

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(01)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(02)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(03)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(ii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(01)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(02)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(03)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 20: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 22: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (e)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 23: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (e)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 24: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 25: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(ii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 26: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 27: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iv)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 28: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(v)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

+ Details

Stockholders' Equity

9 Months Ended

Jun. 30, 2024

Equity [Abstract]

Stockholders' Equity

STOCKHOLDERS’ EQUITY

The following table summarizes the Company’s shares of common stock and preferred stock:


			Shares
	Par Value		Authorized	Issued	Outstanding
			(in thousands)
As of June 30, 2024
Common stock	$	0.001	290,000	124,227	124,227
Preferred stock	$	0.001	5,000	—	—

As of September 30, 2023
Common stock	$	0.001	290,000	107,312	107,312
Preferred stock	$	0.001	5,000	—	—

As of June 30, 2024 and September 30, 2023, respectively, 11,608,148 and 12,709,837 shares of common stock were reserved for issuance upon exercise of options and vesting of restricted stock units granted or available for grant under the Company’s 2013 and 2021 Incentive Plans, as well as for other inducement grants made to new employees under Rule 5635(c)(4) of the Nasdaq Listing Rules.

On January 2, 2024, the Company entered into an underwriting agreement with Jefferies LLC, BofA Securities, Inc., and Cowen and Company, LLC, as representatives of the several underwriters. The Company issued 15,790,000 shares of common stock at an offering price of $28.50 per share. The aggregate purchase price paid by investors was $450.0 million and the Company received net proceeds of $429.3 million after deducting advisory fees and offering expenses.

On December 2, 2022, the Company entered into an open market sale agreement (the “Open Market Sale Agreement”), pursuant to which the Company may, from time to time, sell up to $250,000,000 in shares of the Company’s common stock through Jefferies LLC, acting as the sales agent and/or principal, in an at-the-market offering (“ATM Offering”). The Company is not required to sell shares under the Open Market Sale Agreement. The Company will pay Jefferies LLC a commission of up to 3.0% of the aggregate gross proceeds received from all sales of the common stock under the Open Market Sale Agreement. Unless otherwise terminated, the ATM Offering shall terminate upon the earlier of (i) the sale of all shares of common stock subject to the Open Market Sale Agreement and (ii) the termination of the Open Market Sale Agreement as permitted therein. The Company and Jefferies may each terminate the Open Market Sale Agreement at any time upon prior notice. As of June 30, 2024, no shares have been issued under the Open Market Sale Agreement.

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478448/946-505-50-6

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480237/815-40-50-6

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/505/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-16

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

+ Details

Liability Related to the Sale of Future Royalties - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	9 Months Ended
	Nov. 30, 2022	Jun. 30, 2024	Jun. 30, 2024
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payment received			$ 50,000
Royalty Pharma Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payment	$ 250,000
Milestone payment receivable	160,000
Milestone payment receivable upon FDA approval	50,000
Milestone payment receivable upon receipt of royalty payments	60,000
Royalty payment threshold	70,000
Milestone payment received		$ 50,000
Liability related to the sale of future royalties		$ 250,000	$ 250,000
Liability related to the sale of future royalties, interest rate		6.30%	6.30%
Royalty Pharma Agreement \| Amgen
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payment receivable upon achievement of enrollment in phase 3 clinical trial		$ 50,000	$ 50,000
Royalty Pharma Agreement \| Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Initial transaction price	$ 410,000

Leases - Narrative (Details) ft² in Thousands, $ in Millions	3 Months Ended	9 Months Ended
	Jun. 30, 2023 USD ($)	Jun. 30, 2024 USD ($) ft² option	Jun. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)	Sep. 25, 2023 USD ($)
Lessee Lease Description [Line Items]
Short-term lease cost \| $	$ 0.6	$ 0.0	$ 1.2
Corporate Headquarters In Pasadena \| California
Lessee Lease Description [Line Items]
Office space leases (in sq ft) \| ft²		49
Corporate Headquarters In Pasadena \| California \| Colorado Owner, LLC
Lessee Lease Description [Line Items]
Number of options to renew \| option		1
Operating lease renewal term		5 years
Research Facility in San Diego \| California
Lessee Lease Description [Line Items]
Office space leases (in sq ft) \| ft²		144
Operating lease renewal term		10 years
Lease term		15 years
Maximum additional tenant improvement allowance \| $		$ 7.2			$ 23.6
Additional tenant improvement allowance interest per annum		7.00%			9.00%
Additional tenant improvement allowance liability \| $				$ 30.8
Research Facility in San Diego \| California \| Maximum
Lessee Lease Description [Line Items]
Number of options to renew \| option		1
Research Facility in Madison \| Wisconsin
Lessee Lease Description [Line Items]
Office space leases (in sq ft) \| ft²		115
Number of options to renew \| option		2
Operating lease renewal term		5 years

Net Loss Per Share - Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Numerator:
Net loss attributable to Arrowhead Pharmaceuticals, Inc.	$ (170,793)	$ (102,946)	$ (428,957)	$ (95,596)
Denominator:
Weighted-average basic shares outstanding (in shares)	124,199	107,004	118,260	106,597
Effect of dilutive securities (in shares)	0	0	0	0
Weighted-average diluted shares outstanding (in shares)	124,199	107,004	118,260	106,597
Basic net loss per share (in dollars per share)	$ (1.38)	$ (0.96)	$ (3.63)	$ (0.90)
Diluted net loss per share (in dollars per share)	$ (1.38)	$ (0.96)	$ (3.63)	$ (0.90)

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

+ References

+ Details

- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

+ References

+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

Leases

9 Months Ended

Jun. 30, 2024

Leases [Abstract]

Leases

LEASES

Pasadena, California: The Company leases 49,000 square feet of office space located at 177 East Colorado Blvd. for its corporate headquarters from 177 Colorado Owner, LLC, which lease expires on April 30, 2027. The lease contains an option to renew for one additional five-year term. The Company is not reasonably certain that it will exercise this option to

renew and therefore it is not included in right-of-use assets and liabilities as of June 30, 2024.

San Diego, California: The Company leases 144,000 square feet of office and research and development laboratory space located at 10102 Hoyt Park from 11404 & 11408 Sorrento Valley Owner, LLC, which lease expires on April 30, 2038. Pursuant to the lease, within twelve months of the expiration of the initial 15-year term, the Company has the option to extend the lease for up to one additional ten-year term, with certain annual increases in base rent. The Company is not reasonably certain that it will exercise this option to renew and therefore it is not included in right-of-use assets and liabilities as of June 30, 2024.

The lease agreement grants the Company the right to receive an Additional Tenant Improvement Allowance (“ATIA”) funded by the lessor, with a maximum amount of $7.2 million, subject to a 7% interest per annum over the base term. Further, on September 25, 2023, the Company executed the first amendment to the lease, which grants a second ATIA with a maximum amount of $23.6 million, bearing interest at a rate of 9% per annum over the base term. The Company received $30.8 million ATIA from the lessor during the first quarter of fiscal 2024. As a result, the Company remeasured its lease liability and right-of-use assets to reflect these additional allowances and the related increased lease payments. The Company has further concluded that these ATIAs have no effects on the classification of the lease.

The Company previously subleased additional research and development space in San Diego, California, which sublease ended during the fiscal year of 2023.

Madison, Wisconsin: The Company leases 115,000 square feet space located at 502 South Rosa Road for its office and laboratory facilities, which lease expires on September 30, 2031. The lease contains options to renew for two terms of five years. The Company is not reasonably certain that it will exercise this option and therefore it is not included in right-of-use assets and liabilities as of June 30, 2024.

The components of lease assets and liabilities along with their classification on the Company’s consolidated balance sheets were as follows:


Lease Assets and Liabilities	Classification	June 30, 2024		September 30, 2023
		(in thousands)

Operating lease assets	Right-of-use assets	$	44,339	$	45,297

Current operating lease liabilities	Lease liabilities	6,053		10,563

Non-current operating lease liabilities	Lease liabilities, net of current portion	112,040		104,608


			Three Months Ended June 30,				Nine Months Ended June 30,
Lease Cost	Classification		2024		2023		2024		2023
		(in thousands)

Operating lease cost	Research and development		$	2,965	$	3,323	$	8,531	$	7,735
	General and administrative expense		537		509		1,504		1,542

Variable lease cost (1)	Research and development		863		257		2,478		627
	General and administrative expense		—		—		—		—

Total			$	4,365	$	4,089	$	12,513	$	9,904

(1) Variable lease cost is primarily related to operating expenses associated with the Company’s operating leases.

There was no short-term lease cost during the nine months ended June 30, 2024. There was $0.6 million and $1.2 million short-term lease cost during the three and nine months ended June 30, 2023, respectively.

The following table presents maturities of operating lease liabilities on an undiscounted basis as of June 30, 2024:


Year	Amounts
	(in thousands)
2024 (remainder of fiscal year)	$	3,793
2025	15,356
2026	15,696
2027	14,869
2028	13,511
2029 and thereafter	128,356
Total	$	191,581
Less imputed interest	$	(73,488)
Total operating lease liabilities (includes current portion)	$	118,093

Supplemental cash flow and other information related to leases was as follows:


	Three Months Ended June 30,				Nine Months Ended June 30,
	2024		2023		2024			2023
	(in thousands)



Cash received for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	—	$	5,414	$	3,099		$	23,343
Right-of-use assets adjusted in exchange for new/amended operating lease liabilities	$	—	$	3,519	$	(64)		$	(19,063)
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	3,204	$	1,885	$	7,221		$	4,081

					June 30,
					2024			2023
Weighted-average remaining lease term (in years)					12.8			13.4
Weighted-average discount rate					8.0		%	8.0		%

Cover - shares	9 Months Ended
Cover - shares	Jun. 30, 2024	Aug. 01, 2024
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2024
Document Transition Report	false
Entity File Number	001-38042
Entity Registrant Name	ARROWHEAD PHARMACEUTICALS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	46-0408024
Entity Address, Address Line One	177 E. Colorado Blvd
Entity Address, Address Line Two	Suite 700
Entity Address, City or Town	Pasadena
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	91105
City Area Code	626
Local Phone Number	304-3400
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	ARWR
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		124,315,274
Entity Central Index Key	0000879407
Current Fiscal Year End Date	--09-30
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q3
Amendment Flag	false

Intangible Assets - Expected Future Amortization (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Sep. 30, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
2024 (remainder)	$ 425
2025	1,700
2026	1,700
2027	1,700
2028	1,700
Thereafter	1,762
Net Carrying Amount	$ 8,987	$ 10,262

Leases - Supplemental Cash Flow and Other Information Related to Leases (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Cash received for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 0	$ 5,414	$ 3,099	$ 23,343
Right-of-use assets adjusted in exchange for new/amended operating lease liabilities	0	3,519	(64)	(19,063)
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 3,204	$ 1,885	$ 7,221	$ 4,081
Weighted-average remaining lease term (in years)	12 years 9 months 18 days	13 years 4 months 24 days	12 years 9 months 18 days	13 years 4 months 24 days
Weighted-average discount rate	8.00%	8.00%	8.00%	8.00%

Consolidated Statements of Stockholders’ Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit	Non- controlling Interest
Beginning balance at Sep. 30, 2022	$ 418,339	$ 198	$ 1,219,213	$ (136)	$ (820,755)	$ 19,819
Beginning balance (in shares) at Sep. 30, 2022		105,960,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	19,390		19,390
Exercise of stock options	576		576
Exercise of stock options (in shares)		82,000
Common stock - restricted stock units vesting	0	$ 1	(1)
Common stock - restricted stock units vesting (in shares)		98,000
Foreign currency translation adjustments	(122)			(122)
Net income (loss)	(41,811)				(41,325)	(486)
Ending balance at Dec. 31, 2022	396,372	$ 199	1,239,178	(258)	(862,080)	19,333
Ending balance (in shares) at Dec. 31, 2022		106,140,000
Beginning balance at Sep. 30, 2022	418,339	$ 198	1,219,213	(136)	(820,755)	19,819
Beginning balance (in shares) at Sep. 30, 2022		105,960,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Foreign currency translation adjustments	(275)
Change in unrealized losses on available-for-sale securities	0
Net income (loss)	(98,260)
Ending balance at Jun. 30, 2023	381,985	$ 199	1,281,393	(411)	(916,351)	17,155
Ending balance (in shares) at Jun. 30, 2023		107,102,000
Beginning balance at Dec. 31, 2022	396,372	$ 199	1,239,178	(258)	(862,080)	19,333
Beginning balance (in shares) at Dec. 31, 2022		106,140,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	20,612		20,612
Exercise of stock options	520		520
Exercise of stock options (in shares)		64,000
Common stock - restricted stock units vesting (in shares)		665,000
Foreign currency translation adjustments	(74)			(74)
Net income (loss)	47,676				48,675	(999)
Ending balance at Mar. 31, 2023	465,106	$ 199	1,260,310	(332)	(813,405)	18,334
Ending balance (in shares) at Mar. 31, 2023		106,869,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	19,947		19,947
Exercise of stock options	1,136		1,136
Exercise of stock options (in shares)		198,000
Common stock - restricted stock units vesting (in shares)		35,000
Foreign currency translation adjustments	(79)			(79)
Change in unrealized losses on available-for-sale securities	0
Net income (loss)	(104,125)				(102,946)	(1,179)
Ending balance at Jun. 30, 2023	381,985	$ 199	1,281,393	(411)	(916,351)	17,155
Ending balance (in shares) at Jun. 30, 2023		107,102,000
Beginning balance at Sep. 30, 2023	287,162	$ 200	1,300,395	(3,222)	(1,026,030)	15,819
Beginning balance (in shares) at Sep. 30, 2023		107,312,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	19,694		19,694
Exercise of stock options	267		267
Exercise of stock options (in shares)		34,000
Common stock - restricted stock units vesting (in shares)		154,000
Foreign currency translation adjustments	58			58
Change in unrealized losses on available-for-sale securities	1,909			1,909
Net income (loss)	(135,376)				(132,864)	(2,512)
Ending balance at Dec. 31, 2023	173,714	$ 200	1,320,356	(1,255)	(1,158,894)	13,307
Ending balance (in shares) at Dec. 31, 2023		107,500,000
Beginning balance at Sep. 30, 2023	$ 287,162	$ 200	1,300,395	(3,222)	(1,026,030)	15,819
Beginning balance (in shares) at Sep. 30, 2023		107,312,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)	197,398
Foreign currency translation adjustments	$ (139)
Change in unrealized losses on available-for-sale securities	2,374
Net income (loss)	(436,349)
Ending balance at Jun. 30, 2024	338,974	$ 217	1,786,304	(987)	(1,454,987)	8,427
Ending balance (in shares) at Jun. 30, 2024		124,227,000
Beginning balance at Dec. 31, 2023	173,714	$ 200	1,320,356	(1,255)	(1,158,894)	13,307
Beginning balance (in shares) at Dec. 31, 2023		107,500,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	17,750		17,750
Exercise of stock options	1,512		1,512
Exercise of stock options (in shares)		120,000
Common stock - restricted stock units vesting	0	$ 1	(1)
Common stock - restricted stock units vesting (in shares)		723,000
Common stock issued, net of offering costs	429,265	$ 16	429,249
Common stock issued, net of offering costs (in shares)		15,790,000
Foreign currency translation adjustments	(56)			(56)
Change in unrealized losses on available-for-sale securities	216			216
Net income (loss)	(126,996)				(125,300)	(1,696)
Ending balance at Mar. 31, 2024	495,405	$ 217	1,768,866	(1,095)	(1,284,194)	11,611
Ending balance (in shares) at Mar. 31, 2024		124,133,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	17,050		17,050
Exercise of stock options	388		388
Exercise of stock options (in shares)		43,000
Common stock - restricted stock units vesting (in shares)		51,000
Foreign currency translation adjustments	(141)			(141)
Change in unrealized losses on available-for-sale securities	249			249
Net income (loss)	(173,977)				(170,793)	(3,184)
Ending balance at Jun. 30, 2024	$ 338,974	$ 217	$ 1,786,304	$ (987)	$ (1,454,987)	$ 8,427
Ending balance (in shares) at Jun. 30, 2024		124,227,000

Investments (Tables)

9 Months Ended

Jun. 30, 2024

Investments, Debt and Equity Securities [Abstract]

Summary of Short-term and Long-term Investments and Marketable Securities

The Company’s investments consisted of the following:


	As of June 30, 2024
	(in thousands)
	Adjusted Basis		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value


Available-for-sale securities	$	367,862	$	8	$	(598)	$	367,272

Total current investments	$	367,862	$	8	$	(598)	$	367,272


	As of September 30, 2023
	(in thousands)
	Adjusted Basis		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value


Available-for-sale securities	$	295,699	$	3	$	(2,967)	$	292,735

Total current investments	$	295,699	$	3	$	(2,967)	$	292,735

Subsequent Events	9 Months Ended
Subsequent Events	Jun. 30, 2024
Subsequent Events [Abstract]
Subsequent Events	SUBSEQUENT EVENTS Financing Agreement On August 7, 2024 (the “Closing Date”), the Company entered into a financing agreement (the “Financing Agreement”) with the guarantors party thereto, the lenders party thereto (the “Lenders”), and Sixth Street Lending Partners, as the administrative agent and collateral agent for the Lenders. The Financing Agreement provides for a senior secured term loan facility of $500.0 million (the “Credit Facility”), which includes $400.0 million funded on the Closing Date with an additional $100.0 million at the Company’s option, subject to mutual agreement between Sixth Street and the Company, during the seven-year term of the agreement. The Credit Facility matures on August 7, 2031 (the “Maturity Date”) and bears interest at an annual rate equal to 15.0%. The Credit Facility does not provide for scheduled amortization payments during the term, and all principal will be due on the Maturity Date. The Company has the right to prepay loans under the Financing Agreement at any time. See Item 5. Other Information of Part II, for more information.

Stock-Based Compensation (Tables)

9 Months Ended

Jun. 30, 2024

Share-Based Payment Arrangement [Abstract]

Summary of Awards Outstanding

The following table presents a summary of awards outstanding:


	As of June 30, 2024
	2013 Plan	2021 Plan	Inducement Awards	Total
Granted and outstanding awards:
Options	1,315,326	32,151	665,020	2,012,497
Restricted stock units	1,609,260	2,804,026	616,638	5,029,924
Total	2,924,586	2,836,177	1,281,658	7,042,421

Share-Based Payment Arrangement, Expensed

The following table summarizes stock-based compensation expenses included in operating expenses:


	Three Months Ended June 30,				Nine Months Ended June 30,
	2024		2023		2024		2023


Research and development	$	6,221	$	8,982	$	21,634	$	26,129
General and administrative	8,490		10,965		27,350		33,820
Total	$	14,711	$	19,947	$	48,984	$	59,949

Summarized Information about Stock Options

The following table presents a summary of the stock option activity for the nine months ended June 30, 2024:


	Shares	Weighted- Average Exercise Price Per Share		Weighted- Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value
Outstanding at September 30, 2023	2,263,477	$	22.68
Granted	—	—
Cancelled or expired	(53,582)	36.62
Exercised	(197,398)	10.98
Outstanding at June 30, 2024	2,012,497	$	23.22	3.8	$	22,486,304
Exercisable at June 30, 2024	2,001,968	$	23.05	3.8	$	22,486,304

Assumptions Used to Value Stock Options

The following table provides the assumptions used in the calculation of grant-date fair values of these stock options based on the Black-Scholes option pricing model:


	Nine Months Ended June 30,
	2024(5)	2023
Expected dividend yield(1)	N/A	—
Risk-free interest rate(2)	N/A	3.69%
Expected volatility(3)	N/A	86.4%
Expected term (in years)(4)	N/A	6.25
Weighted average grant date fair value per share of options granted	N/A	$24.80

(1) The dividend yield is zero as the Company currently does not pay a dividend.

(2) The risk-free interest rate is based on that of the U.S. Treasury yields with equivalent terms in effect at the time of the grant.

(3) Volatility is estimated based on volatility average of the Company’s common stock price.

(4) The computation of expected term was determined based on safe harbor rules, considering the contractual terms of the awards and vesting schedules.

(5) No options were granted during the nine months ended June 30, 2024.

Summary of Share Activity Related to RSUs

The following table summarizes the activity of the Company’s RSUs:


	Number of RSUs	Weighted- Average Grant Date Fair Value Per Share
Outstanding at September 30, 2023	4,241,640	$	58.43
Granted	1,876,825	30.67
Vested	(927,766)	53.16
Forfeited	(160,775)	41.75
Outstanding at June 30, 2024	5,029,924	$	49.58

Intangible Assets (Tables)

9 Months Ended

Jun. 30, 2024

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Finite-Lived Intangible Assets

The following table presents the components of intangible assets:


	Gross Carrying Amount		Accumulated Amortization		Impairment		Net Carrying Amount		Useful Lives
	(in thousands)								(in years)
As of June 30, 2024
Patents	$	21,728	$	14,485	$	—	$	7,243	14
License	3,129		1,385		—		1,744		21
Total intangible assets, net	$	24,857	$	15,870	$	—	$	8,987

As of September 30, 2023
Patents	$	21,728	$	13,321	$	—	$	8,407	14
License	3,129		1,274		—		1,855		21
Total intangible assets, net	$	24,857	$	14,595	$	—	$	10,262

Schedule of Intangible Assets Future Amortization Expense

The following table presents the estimated future amortization expense related to intangible assets as of June 30, 2024:


	Amortization Expense
Year Ending September 30,	(in thousands)
2024 (remainder)	$	425
2025	1,700
2026	1,700
2027	1,700
2028	1,700
Thereafter	1,762
Total	$	8,987

Collaboration and License Agreements - Glaxosmithkline Intellectual Property (No. 3) Limited (Details) - USD ($)	1 Months Ended
	Dec. 31, 2023	Jun. 30, 2024	Dec. 11, 2023	Sep. 30, 2023	Jun. 30, 2023	Nov. 22, 2021
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Contract liabilities		$ 0		$ 866,000
GSK \| GSK-HSD License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payment receivable					$ 30,000,000
Milestone payment receivable upon achievement of phase two and first patient dosed in phase three						$ 100,000,000.0
GSK \| GSK-HSD License Agreement \| Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Commercial milestone payments at first commercial sale						190,000,000.0
Sales-related milestone payments						$ 590,000,000.0
GSK \| GSK-HBV Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Initial transaction price	$ 2,700,000
Contract assets		0
Contract liabilities		$ 0
GSK \| GSK-HBV Agreement \| Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Development and sales milestone payments			$ 832,500,000

Collaboration and License Agreements - Takeda Pharmaceutical Company Limited (Details) $ in Thousands	1 Months Ended
	Oct. 31, 2020 USD ($) obligation bundle	Jun. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Mar. 31, 2023 USD ($)
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Development regulatory and sales milestones payments		$ 2,700,000
Accrued expenses		47,899	$ 39,763
Takeda \| License and Co-Funding Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of distinct performance obligations \| obligation	1
Number of distinct bundle \| bundle	1
Initial transaction price	$ 300,000
Milestone payment				$ 40,000
Accrued expenses		21,300
Takeda \| License and Co-Funding Agreement \| Minimum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Percentage of eligible to receive tiered royalties on net sales	20.00%
Takeda \| License and Co-Funding Agreement \| Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Percentage of eligible to receive tiered royalties on net sales	25.00%
Development regulatory and sales milestones payments		$ 527,500

Liability Related to the Sale of Future Royalties (Tables)

9 Months Ended

Jun. 30, 2024

Schedule of Liability Related to the Sale of Future Royalties

The following table presents the activity with respect to the liability related to the sale of future royalties.


	Carrying Amount
	(in thousands)
Carrying value as of September 30, 2023	$	268,326
Milestone payment received	50,000
Non-cash interest expense recognized	17,705
Carrying value as of June 30, 2024	$	336,031

Fair Value Measurements

9 Months Ended

Jun. 30, 2024

Fair Value Disclosures [Abstract]

Fair Value Measurements

FAIR VALUE MEASUREMENTS

The Company employs a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The Company’s valuation techniques and inputs used to measure fair value and the definition of the three levels (Level 1, Level 2, and Level 3) of the fair value hierarchy are disclosed in Note 10 - Fair Value Measurements of Notes to Consolidated Financial Statements of Part IV, “Item 15. Exhibits and Financial Statement Schedules” of its Annual Report on Form 10-K for the year ended September 30, 2023.

The Company uses prices and inputs that are current as of the measurement date, including during periods of market disruption. In periods of market disruption, the ability to observe prices and inputs may be reduced for many instruments. This condition could cause an instrument to be reclassified from Level 1 to Level 2, or from Level 2 to Level 3. The Company recognizes transfers between levels at either the actual date of the event or a change in circumstances that caused the transfer. At June 30, 2024 and September 30, 2023, the Company did not have any financial assets or financial liabilities based on Level 3 measurements.

The following table presents information about the Company’s assets and liabilities measured at fair value on a recurring basis, and indicates the fair value hierarchy of the valuation techniques utilized by the Company:


	June 30, 2024
	Level 1		Level 2		Level 3		Total
	(in thousands)

Available-for-sale securities
U.S. government bonds	$	—	$	80,946	$	—	$	80,946
Commercial notes	—		114,616		—		114,616
Corporate debt securities	—		171,710		—		171,710
Total available-for-sale securities	—		367,272		—		367,272
Cash equivalents
Money market instruments	29,495		—		—		29,495
Commercial notes	—		4,986		—		4,986
Total cash equivalents	29,495		4,986		—		34,481
Total financial assets	$	29,495	$	372,258	$	—	$	401,753


	September 30, 2023
	Level 1		Level 2		Level 3		Total
	(in thousands)

Available-for-sale securities
U.S. government bonds	$	31,553	$	—	$	—	$	31,553
Municipal securities	—		7,093		—		7,093
Commercial notes	—		22,205		—		22,205
Corporate debt securities	—		231,884		—		231,884
Total available-for-sale securities	31,553		261,182		—		292,735
Cash equivalents
Money market instruments	39,733		—		—		39,733
Total cash equivalents	39,733		—		—		39,733
Total financial assets	$	71,286	$	261,182	$	—	$	332,468

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 107
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-107

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 100
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-100

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2E
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2E

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 940
-SubTopic 820
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478119/940-820-50-1

+ Details

Stock-Based Compensation - Expenses Included in Operating Expenses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 14,711	$ 19,947	$ 48,984	$ 59,949
Research and development
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	6,221	8,982	21,634	26,129
General and administrative expense
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 8,490	$ 10,965	$ 27,350	$ 33,820

Organization and Significant Accounting Policies (Tables)

9 Months Ended

Jun. 30, 2024

Accounting Policies [Abstract]

Schedule of Company's Current Pipeline

The following table presents the Company’s current pipeline:


Therapeutic Area	Name	Stage	Product Rights
Cardiometabolic	plozasiran (ARO-APOC3)	Phase 3	Arrowhead
	zodasiran (ARO-ANG3)	Phase 2b	Arrowhead
	olpasiran	Phase 3	Amgen
Pulmonary	ARO-RAGE	Phase 1/2a	Arrowhead
	ARO-MUC5AC	Phase 1/2a	Arrowhead
	ARO-MMP7	Phase 1/2a	Arrowhead
Liver	GSK-4532990	Phase 2b	GSK
	fazirsiran	Phase 3	Takeda and Arrowhead
	daplusiran/tomligisiran (GSK5637608, formerly JNJ-3989)	Phase 2	GSK
	ARO-PNPLA3	Phase 1	Arrowhead
	ARO-C3	Phase 1/2a	Arrowhead
	ARO-CFB	Phase 1/2a	Arrowhead
Muscle	ARO-DUX4	Phase 1/2a	Arrowhead
	ARO-DM1	Phase 1/2a	Arrowhead
Central Nervous System (CNS)	Various	Pre-Clinical	Arrowhead

Investments - Summary of Short-term, Long-term Investments and Marketable Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Sep. 30, 2023
Schedule Of Held To Maturity Securities And Marketable Securities [Line Items]
Current investments, Available-for-sale, Adjusted Basis	$ 367,862	$ 295,699
Current investments, Available-for-sale, Gross Unrealized Gains	8	3
Current investments, Available-for-sale, Gross Unrealized Losses	(598)	(2,967)
Current investments, Available-for-sale, Fair Value	367,272	292,735
Debt securities
Schedule Of Held To Maturity Securities And Marketable Securities [Line Items]
Current investments, Available-for-sale, Adjusted Basis	367,862	295,699
Current investments, Available-for-sale, Gross Unrealized Gains	8	3
Current investments, Available-for-sale, Gross Unrealized Losses	(598)	(2,967)
Current investments, Available-for-sale, Fair Value	$ 367,272	$ 292,735

Collaboration and License Agreements (Tables)

9 Months Ended

Jun. 30, 2024

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Summary of Revenue

The following table provides a summary of revenue recognized:


	Three Months Ended June 30,				Nine Months Ended June 30,
	2024		2023		2024		2023
	(in thousands)
GSK	$	—	$	277	$	2,685	$	29,600
Horizon	—		1,539		—		23,206
Takeda	—		14,009		866		146,477
Janssen	—		—		—		355
Amgen	—		—		—		25,000
Total	$	—	$	15,825	$	3,551	$	224,638

Schedule of Receivables and Contract Liabilities

The following table summarizes the balance of receivables and contract liabilities related to the Company’s

collaboration and license agreements:


	June 30, 2024		September 30, 2023
	(in thousands)
Receivables included in accounts receivable	$	—	$	—
Contract liabilities included in deferred revenue	$	—	$	866

Stock-Based Compensation - Summarize Information about Stock Options (Details) - USD ($)	9 Months Ended
	Jun. 30, 2024
Shares
Beginning balance (in shares)	2,263,477
Granted (in shares)	0
Cancelled (in shares)	(53,582)
Exercised (in shares)	(197,398)
Ending balance (in shares)	2,012,497
Number of Options Outstanding, Exercisable (in shares)	2,001,968
Weighted- Average Exercise Price Per Share
Beginning balance (in dollars per share)	$ 22.68
Granted (in dollars per share)	0
Cancelled (in dollars per share)	36.62
Exercised (in dollars per share)	10.98
Ending balance (in dollars per share)	23.22
Weighted-Average Exercise Price Per Share, Exercisable (in dollars per share)	$ 23.05
Weighted- Average Remaining Contractual Term (Years)	3 years 9 months 18 days
Weighted-Average Remaining Contractual Term, Exercisable	3 years 9 months 18 days
Aggregate Intrinsic Value	$ 22,486,304
Aggregate Intrinsic Value, Exercisable	$ 22,486,304

Collaboration and License Agreements - Horizon Therapeutics Ireland DAC (Details) - Horizon - Horizon License Agreement $ in Millions	1 Months Ended
	Jul. 31, 2021 USD ($)	Jun. 30, 2021 obligation	Jan. 31, 2023 USD ($)
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of distinct performance obligations \| obligation		1
Initial transaction price	$ 40.0
Milestone payment			$ 15.0

Commitments and Contingencies	9 Months Ended
Commitments and Contingencies	Jun. 30, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES Litigation From time to time, the Company may be subject to various claims and legal proceedings in the ordinary course of business. If the potential loss from any claim, asserted or unasserted, or legal proceeding is considered probable and the amount is reasonably estimable, the Company will accrue a liability for the estimated loss. There were no contingent liabilities recorded as of June 30, 2024. Commitments The Company owns land in the Verona Technology Park in Verona, Wisconsin, which is being developed into an approximately 160,000 square foot drug manufacturing facility and an approximately 140,000 square foot laboratory and office facility which will support the Company’s manufacturing process development and analytical activities. During the first quarter of fiscal 2024, the Company completed the build out of one of its laboratory and office facilities. As of June 30, 2024, the Company has incurred $266.0 million and intends to spend an additional $18.0 million to $32.0 million to complete the build out of the facilities.

Collaboration and License Agreements - Receivables and Contract Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Sep. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Receivables included in accounts receivable	$ 0	$ 0
Contract liabilities included in deferred revenue	$ 0	$ 866

Collaboration and License Agreements - Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Disaggregation of Revenue [Line Items]
Revenue	$ 0	$ 15,825	$ 3,551	$ 224,638
GSK
Disaggregation of Revenue [Line Items]
Revenue	0	277	2,685	29,600
Horizon
Disaggregation of Revenue [Line Items]
Revenue	0	1,539	0	23,206
Takeda
Disaggregation of Revenue [Line Items]
Revenue	0	14,009	866	146,477
Janssen
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	355
Amgen
Disaggregation of Revenue [Line Items]
Revenue	$ 0	$ 0	$ 0	$ 25,000

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

- Definition

+ References

+ Details

Stockholders' Equity (Details) - USD ($)	Jan. 02, 2024	Dec. 02, 2022	Jun. 30, 2024	Sep. 30, 2023
Class Of Stock [Line Items]
Common stock, par value (in dollars per share)			$ 0.001	$ 0.001
Common stock, shares authorized (in shares)			290,000,000	290,000,000
Common stock, shares issued (in shares)			124,227,000	107,312,000
Common stock, shares outstanding (in shares)			124,227,000	107,312,000
Preferred stock, par value (in dollars per share)			$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)			5,000,000	5,000,000
Preferred stock, shares issued (in shares)			0	0
Preferred stock, shares outstanding (in shares)			0	0
Common stock, share reserve for issuance (in shares)			4,565,727
Underwriting Agreement
Class Of Stock [Line Items]
Shares of common stock issued (in shares)	15,790,000
Common stock offering price (in dollars per share)	$ 28.50
Aggregate purchase price paid by investors	$ 450,000,000
Net proceeds	$ 429,300,000
At The Market Agreement
Class Of Stock [Line Items]
Shares issued			0
At The Market Agreement \| Maximum
Class Of Stock [Line Items]
Common stock shares value reserved for future issuance		$ 250,000,000
Percentage of commission to sales agent		3.00%
2013 and 2021 Incentive Plans and other inducement grants
Class Of Stock [Line Items]
Common stock, share reserve for issuance (in shares)			11,608,148	12,709,837

Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2024	Sep. 30, 2023
Statement of Financial Position [Abstract]
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	290,000,000	290,000,000
Common stock, shares issued (in shares)	124,227,000	107,312,000
Common stock, shares outstanding (in shares)	124,227,000	107,312,000

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$ (436,349)	$ (98,260)
Adjustments to reconcile net loss to net cash flow from operating activities
Stock-based compensation	54,494	59,949
Depreciation and amortization	13,570	8,634
Amortization (accretion) of note premiums/discounts	7,886	(1,030)
Realized gain on investments	(80)	0
Non-cash interest expense on liability related to the sale of future royalties	17,705	13,064
Changes in operating assets and liabilities:
Accounts receivable	0	164
Prepaid expenses and other assets	(1,746)	27,913
Accounts payable	2,785	5,001
Accrued expenses	13,086	(32,082)
Deferred revenue	(866)	(113,144)
Operating lease, net	3,880	1,827
Net cash used in operating activities	(325,635)	(127,964)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of property and equipment	(117,180)	(112,830)
Purchases of investments	(428,611)	(233,984)
Proceeds from sales and maturities of investments	348,642	220,150
Net cash used in investing activities	(197,149)	(126,664)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from the exercises of stock options	2,166	2,232
Proceeds from the issuance of common stock, net of offering costs	429,265	0
Proceeds from the sale of future royalties	50,000	250,000
Net cash provided by financing activities	481,431	252,232
Net decrease in cash, cash equivalents and restricted cash	(41,353)	(2,396)
Effect of exchange rate on cash, cash equivalents and restricted cash	(139)	(275)
CASH, CASH EQUIVALENTS AND RESTRICTED CASH:
BEGINNING OF PERIOD	110,891	108,005
END OF PERIOD	69,399	105,334
Supplementary disclosure of cash flows:
Income taxes paid	(3,062)	0
Supplemental disclosure of non-cash investing activities:
Capital expenditures included in accrued expenses	$ 6,909	$ 15,624

Intangible Assets

9 Months Ended

Jun. 30, 2024

Goodwill and Intangible Assets Disclosure [Abstract]

Intangible Assets

INTANGIBLE ASSETS

Intangible assets subject to amortization include patents and a license agreement capitalized as part of the Novartis RNAi asset acquisition in March 2015. The following table presents the components of intangible assets:


	Gross Carrying Amount		Accumulated Amortization		Impairment		Net Carrying Amount		Useful Lives
	(in thousands)								(in years)
As of June 30, 2024
Patents	$	21,728	$	14,485	$	—	$	7,243	14
License	3,129		1,385		—		1,744		21
Total intangible assets, net	$	24,857	$	15,870	$	—	$	8,987

As of September 30, 2023
Patents	$	21,728	$	13,321	$	—	$	8,407	14
License	3,129		1,274		—		1,855		21
Total intangible assets, net	$	24,857	$	14,595	$	—	$	10,262

Intangible assets are reviewed annually for impairment and more frequently if potential impairment indicators exist. No impairment indicators were identified during the nine months ended June 30, 2024 and 2023.

Intangible assets with definite useful lives are amortized on a straight-line basis over their useful lives. Intangible assets amortization expense was $0.4 million for the three months ended June 30, 2024 and 2023, and $1.3 million for the nine months ended June 30, 2024 and 2023. None of the intangible assets with definite useful lives are anticipated to have a residual value.

The following table presents the estimated future amortization expense related to intangible assets as of June 30, 2024:


	Amortization Expense
Year Ending September 30,	(in thousands)
2024 (remainder)	$	425
2025	1,700
2026	1,700
2027	1,700
2028	1,700
Thereafter	1,762
Total	$	8,987

Balance Sheet Accounts (Tables)

9 Months Ended

Jun. 30, 2024

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Summary of Property and Equipment

The following table summarizes the Company’s major classes of property, plant and equipment:


	June 30, 2024		September 30, 2023
	(in thousands)
Land	$	2,996	$	2,996
Building	75,868		—
Research equipment	64,207		56,509
Furniture	5,593		1,540
Computers and software	976		700
Leasehold improvements	104,396		103,813
Construction in progress	175,778		166,655
	429,814		332,213
Less: Accumulated depreciation and amortization	(53,903)		(41,951)
Property, plant and equipment, net	$	375,911	$	290,262

Schedule of Accrued Expenses

Accrued expenses consist of the following:


	June 30, 2024		September 30, 2023
	(in thousands)
Accrued R&D expenses	$	17,911	$	16,125
Accrued R&D expenses; co-development	21,280		5,895
Accrued capital expenditures	6,909		14,044
Other	1,799		3,699
Total accrued expenses	$	47,899	$	39,763

Net Loss Per Share (Tables)

9 Months Ended

Jun. 30, 2024

Earnings Per Share [Abstract]

Schedule of Earnings Per Share, Basic and Diluted

The following table presents the computation of basic and diluted net loss per share for the three and nine months ended June 30, 2024 and 2023.


	Three Months Ended June 30,				Nine Months Ended June 30,
	2024		2023		2024		2023
	(in thousands, except per share amounts)
Numerator:
Net loss attributable to Arrowhead Pharmaceuticals, Inc.	$	(170,793)	$	(102,946)	$	(428,957)	$	(95,596)

Denominator:
Weighted-average basic shares outstanding	124,199		107,004		118,260		106,597
Effect of dilutive securities	—		—		—		—
Weighted-average diluted shares outstanding	124,199		107,004		118,260		106,597

Basic net loss per share	$	(1.38)	$	(0.96)	$	(3.63)	$	(0.90)
Diluted net loss per share	$	(1.38)	$	(0.96)	$	(3.63)	$	(0.90)

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share

The following table sets forth the potentially dilutive securities that have been excluded from the calculation of diluted net loss per share because to include them would be anti-dilutive.


	Three Months Ended June 30,		Nine Months Ended June 30,
	2024	2023	2024	2023
	(in thousands)
Options	753	637	711	768
Restricted stock units	3,976	2,830	4,060	3,256
Total	4,729	3,467	4,771	4,024

Balance Sheet Accounts - Summary of Property and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023	Sep. 30, 2023
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 429,814		$ 429,814			$ 332,213
Less: Accumulated depreciation and amortization	(53,903)		(53,903)			(41,951)
Property, plant and equipment, net	375,911		375,911			290,262
Depreciation and amortization expense for property and equipment	4,400	$ 2,900	12,300	$ 7,400
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	2,996		2,996			2,996
Building
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	75,868		75,868			0
Property, plant and equipment, reclassification			75,900
Useful life					39 years
Research equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	64,207		64,207			56,509
Furniture
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	5,593		5,593			1,540
Computers and software
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	976		976			700
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	104,396		104,396			103,813
Construction in progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 175,778		175,778			$ 166,655
Property, plant and equipment, reclassification			$ (75,900)

Stock-Based Compensation

9 Months Ended

Jun. 30, 2024

Share-Based Payment Arrangement [Abstract]

Stock-Based Compensation

STOCK-BASED COMPENSATION

Stock Plans

The Company has two plans that provide for equity-based compensation under the 2013 and the 2021 plans. Under the 2013 Incentive Plan (the “2013 Plan”), 2,924,586 shares of the Company’s common stock are reserved for grants of stock options and restricted stock awards to employees and directors as of June 30, 2024.

Under the 2021 Incentive Plan (the “2021 Plan”), 8,000,000 shares (subject to certain adjustments) of the Company’s common stock are reserved for grants of stock options, stock appreciation rights, restricted and unrestricted stock, performance awards, cash awards and other awards convertible into or otherwise based on shares of the Company’s common stock. The maximum number of shares authorized under the 2021 Plan will be (i) reduced by any shares subject to awards made under the 2013 Plan after January 1, 2021, and (ii) increased by any shares subject to outstanding awards under the 2013 Plan as of January 1, 2021 that, after January 1, 2021, are canceled, expired, forfeited or otherwise not issued under such awards (other than as a result of being tendered or withheld to pay the exercise price or withholding taxes in connection with any such awards) or settled in cash. As of June 30, 2024, the total number of shares available for issuance was 4,565,727 shares, which includes 158,928 and 154,139 shares that were forfeited under the 2013 and 2021 Plans, respectively, and 3,697,189 shares have been granted under the 2021 Plan.

In addition, there were 665,020 shares reserved for options and 616,638 shares reserved for restricted stock units issued as inducement grants to new employees granted outside of the Company’s equity-based compensation plans under Rule 5635(c)(4) of the Nasdaq Listing Rules.

The following table presents a summary of awards outstanding:


	As of June 30, 2024
	2013 Plan	2021 Plan	Inducement Awards	Total
Granted and outstanding awards:
Options	1,315,326	32,151	665,020	2,012,497
Restricted stock units	1,609,260	2,804,026	616,638	5,029,924
Total	2,924,586	2,836,177	1,281,658	7,042,421

The following table summarizes stock-based compensation expenses included in operating expenses:


	Three Months Ended June 30,				Nine Months Ended June 30,
	2024		2023		2024		2023


Research and development	$	6,221	$	8,982	$	21,634	$	26,129
General and administrative	8,490		10,965		27,350		33,820
Total	$	14,711	$	19,947	$	48,984	$	59,949

Stock Option Awards

The following table presents a summary of the stock option activity for the nine months ended June 30, 2024:


	Shares	Weighted- Average Exercise Price Per Share		Weighted- Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value
Outstanding at September 30, 2023	2,263,477	$	22.68
Granted	—	—
Cancelled or expired	(53,582)	36.62
Exercised	(197,398)	10.98
Outstanding at June 30, 2024	2,012,497	$	23.22	3.8	$	22,486,304
Exercisable at June 30, 2024	2,001,968	$	23.05	3.8	$	22,486,304

The aggregate intrinsic values represent the amount by which the market price of the underlying stock exceeds the

exercise price of the option. The total intrinsic value of the options exercised during the three months ended June 30, 2024 and 2023 was $0.7 million and $6.5 million, respectively. The total intrinsic value of the options exercised during the nine months ended June 30, 2024 and 2023 was $3.8 million and $10.1 million, respectively.

Stock-based compensation expense related to stock options outstanding for the three months ended June 30, 2024 and 2023, was $0.4 million and $2.1 million, respectively. Stock-based compensation expense related to stock options outstanding for the nine months ended June 30, 2024 and 2023, was $2.5 million and $6.7 million, respectively.

As of June 30, 2024, the pre-tax compensation expense for all outstanding unvested stock options in the amount of $0.4 million will be recognized in the Company’s results of operations over a weighted average period of 3 months.

The fair value of each stock option award is estimated on the date of grant using the Black-Scholes option pricing model. The Black-Scholes option pricing model was developed for use in estimating the fair value of traded options, which do not have vesting restrictions and are fully transferable. The determination of the fair value of each stock option is affected by the Company’s stock price on the date of grant, as well as assumptions regarding a number of highly complex and subjective variables. Because the Company’s employee stock options have characteristics significantly different from those of traded options, and because changes in the subjective input assumptions can materially affect the fair value estimate, the existing models do not necessarily provide a reliable single measure of the fair value of its employee stock options.

The following table provides the assumptions used in the calculation of grant-date fair values of these stock options based on the Black-Scholes option pricing model:


	Nine Months Ended June 30,
	2024(5)	2023
Expected dividend yield(1)	N/A	—
Risk-free interest rate(2)	N/A	3.69%
Expected volatility(3)	N/A	86.4%
Expected term (in years)(4)	N/A	6.25
Weighted average grant date fair value per share of options granted	N/A	$24.80

(1) The dividend yield is zero as the Company currently does not pay a dividend.

(2) The risk-free interest rate is based on that of the U.S. Treasury yields with equivalent terms in effect at the time of the grant.

(3) Volatility is estimated based on volatility average of the Company’s common stock price.

(4) The computation of expected term was determined based on safe harbor rules, considering the contractual terms of the awards and vesting schedules.

(5) No options were granted during the nine months ended June 30, 2024.

Visirna ESOP: On October 1, 2023, Visirna, a subsidiary of the Company, granted 7,500,000 stock options to its employees from the Employee Stock Option Plan (the “Visirna ESOP”), which authorizes 20,000,000 shares for issuance. The Visirna ESOP is independently managed by Visirna, including the valuation process. For the three and nine months ended June 30, 2024, stock-based compensation expense related to the Visirna ESOP was $2.3 million and $5.5 million, respectively.

Restricted Stock Units

Restricted Stock Units (“RSUs”), including market-based, time-based and performance-based awards, have been granted under the Company’s 2013 and 2021 Plans and as inducements grants granted outside of the Company’s equity-based compensation plans. At vesting, each outstanding RSU will be exchanged for one share of the Company’s common stock. RSU awards generally vest subject to the satisfaction of service requirements or the satisfaction of both service requirements and achievement of certain performance targets.

The following table summarizes the activity of the Company’s RSUs:


	Number of RSUs	Weighted- Average Grant Date Fair Value Per Share
Outstanding at September 30, 2023	4,241,640	$	58.43
Granted	1,876,825	30.67
Vested	(927,766)	53.16
Forfeited	(160,775)	41.75
Outstanding at June 30, 2024	5,029,924	$	49.58

The fair value of RSUs was determined based on the closing price of the Company’s common stock on the grant date, with consideration given to the probability of achieving service and/or performance conditions for awards.

For the three months ended June 30, 2024 and 2023, the Company recorded $14.3 million and $17.8 million of expense related to RSUs, respectively. For the nine months ended June 30, 2024 and 2023, the Company recorded $46.5 million and $53.2 million of expense related to RSUs, respectively. As of June 30, 2024, there was $96.3 million of total unrecognized compensation cost related to RSUs that is expected to be recognized over a weighted-average period of 1.6 years.

Stock-Based Compensation - Assumptions Used to Value Stock Options (Details) - $ / shares	9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Share-Based Payment Arrangement [Abstract]
Expected dividend yield	0.00%	0.00%
Risk-free interest rate		3.69%
Expected volatility		86.40%
Expected life (in years)		6 years 3 months
Weighted average grant date fair value per share of options granted (in dollars per share)		$ 24.80

Insider Trading Arrangements

3 Months Ended

9 Months Ended

Jun. 30, 2024

Trading Arrangements, by Individual

Material Terms of Trading Arrangement

During the quarter ended June 30, 2024, the following directors and officers (as defined in Exchange Act Rule 16a-1(f)) adopted certain trading plans intended to satisfy Rule 10b5-1(c):

Name

Title

Adoption Date

Plan Start Date

Plan End Date

Vesting and

Subject to

Sell-To-

Cover (1)

Other
Shares
Being Sold
(Subject to
Certain
Conditions)

Victoria Vakiener

Board Member

5/15/2024

12/16/2024

12/31/2024

n/a

8,994

(1) This column indicates the total number of shares vesting in connection with equity awards, not the number of shares to be sold. The actual number of shares to be sold will be a smaller number based on whatever is required to satisfy payment of applicable withholding taxes under sell-to-cover arrangements.

Non-Rule 10b5-1 Arrangement Adopted

false

Rule 10b5-1 Arrangement Terminated

false

Non-Rule 10b5-1 Arrangement Terminated

false

Victoria Vakiener [Member]

Trading Arrangements, by Individual

Name

Victoria Vakiener

Title

Board Member

Rule 10b5-1 Arrangement Adopted

true

5/15/2024

12/31/2024

15 days

8,994

Leases - Summary of Maturities of Operating Lease Liabilities on an Undiscounted Basis (Details) $ in Thousands	Jun. 30, 2024 USD ($)
Leases [Abstract]
2024 (remainder of fiscal year)	$ 3,793
2025	15,356
2026	15,696
2027	14,869
2028	13,511
2029 and thereafter	128,356
Total	191,581
Less imputed interest	(73,488)
Total operating lease liabilities (includes current portion)	$ 118,093

Fair Value Measurements (Tables)

9 Months Ended

Jun. 30, 2024

Fair Value Disclosures [Abstract]

Fair Value Measurements for Assets and Liabilities Measured at Fair Value on Recurring Basis


	June 30, 2024
	Level 1		Level 2		Level 3		Total
	(in thousands)

Available-for-sale securities
U.S. government bonds	$	—	$	80,946	$	—	$	80,946
Commercial notes	—		114,616		—		114,616
Corporate debt securities	—		171,710		—		171,710
Total available-for-sale securities	—		367,272		—		367,272
Cash equivalents
Money market instruments	29,495		—		—		29,495
Commercial notes	—		4,986		—		4,986
Total cash equivalents	29,495		4,986		—		34,481
Total financial assets	$	29,495	$	372,258	$	—	$	401,753


	September 30, 2023
	Level 1		Level 2		Level 3		Total
	(in thousands)

Available-for-sale securities
U.S. government bonds	$	31,553	$	—	$	—	$	31,553
Municipal securities	—		7,093		—		7,093
Commercial notes	—		22,205		—		22,205
Corporate debt securities	—		231,884		—		231,884
Total available-for-sale securities	31,553		261,182		—		292,735
Cash equivalents
Money market instruments	39,733		—		—		39,733
Total cash equivalents	39,733		—		—		39,733
Total financial assets	$	71,286	$	261,182	$	—	$	332,468

Balance Sheet Accounts - Accrued Expenses (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Sep. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accrued R&D expenses	$ 17,911	$ 16,125
Accrued R&D expenses; co-development	21,280	5,895
Accrued capital expenditures	6,909	14,044
Other	1,799	3,699
Total accrued expenses	$ 47,899	$ 39,763

Leases (Tables)

9 Months Ended

Jun. 30, 2024

Leases [Abstract]

Schedule of Lease Assets and Liabilities and Lease Cost

The components of lease assets and liabilities along with their classification on the Company’s consolidated balance sheets were as follows:


Lease Assets and Liabilities	Classification	June 30, 2024		September 30, 2023
		(in thousands)

Operating lease assets	Right-of-use assets	$	44,339	$	45,297

Current operating lease liabilities	Lease liabilities	6,053		10,563

Non-current operating lease liabilities	Lease liabilities, net of current portion	112,040		104,608


			Three Months Ended June 30,				Nine Months Ended June 30,
Lease Cost	Classification		2024		2023		2024		2023
		(in thousands)

Operating lease cost	Research and development		$	2,965	$	3,323	$	8,531	$	7,735
	General and administrative expense		537		509		1,504		1,542

Variable lease cost (1)	Research and development		863		257		2,478		627
	General and administrative expense		—		—		—		—

Total			$	4,365	$	4,089	$	12,513	$	9,904

(1) Variable lease cost is primarily related to operating expenses associated with the Company’s operating leases.

Summary of Maturities of Operating Lease Liabilities on an Undiscounted Basis

The following table presents maturities of operating lease liabilities on an undiscounted basis as of June 30, 2024:


Year	Amounts
	(in thousands)
2024 (remainder of fiscal year)	$	3,793
2025	15,356
2026	15,696
2027	14,869
2028	13,511
2029 and thereafter	128,356
Total	$	191,581
Less imputed interest	$	(73,488)
Total operating lease liabilities (includes current portion)	$	118,093

Supplemental cash flow and other information related to leases was as follows:


	Three Months Ended June 30,				Nine Months Ended June 30,
	2024		2023		2024			2023
	(in thousands)



Cash received for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	—	$	5,414	$	3,099		$	23,343
Right-of-use assets adjusted in exchange for new/amended operating lease liabilities	$	—	$	3,519	$	(64)		$	(19,063)
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	3,204	$	1,885	$	7,221		$	4,081

					June 30,
					2024			2023
Weighted-average remaining lease term (in years)					12.8			13.4
Weighted-average discount rate					8.0		%	8.0		%

Collaboration and License Agreements

9 Months Ended

Jun. 30, 2024

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Collaboration and License Agreements

COLLABORATION AND LICENSE AGREEMENTS

The following table provides a summary of revenue recognized:


	Three Months Ended June 30,				Nine Months Ended June 30,
	2024		2023		2024		2023
	(in thousands)
GSK	$	—	$	277	$	2,685	$	29,600
Horizon	—		1,539		—		23,206
Takeda	—		14,009		866		146,477
Janssen	—		—		—		355
Amgen	—		—		—		25,000
Total	$	—	$	15,825	$	3,551	$	224,638

The following table summarizes the balance of receivables and contract liabilities related to the Company’s

collaboration and license agreements:


	June 30, 2024		September 30, 2023
	(in thousands)
Receivables included in accounts receivable	$	—	$	—
Contract liabilities included in deferred revenue	$	—	$	866

Glaxosmithkline Intellectual Property (No. 3) Limited (“GSK”)

GSK-HSD License Agreement

On November 22, 2021, GSK and the Company entered into an Exclusive License Agreement (the “GSK-HSD License Agreement”). Under the GSK-HSD License Agreement, GSK has received an exclusive license for GSK-4532990 (formerly ARO-HSD). The exclusive license is worldwide with the exception of greater China. GSK is wholly responsible for all clinical development and commercialization of GSK-4532990 in its territory. GSK dosed the first patient in a Phase 2b trial in March 2023 and paid a $30.0 million milestone payment to the Company in the third quarter of fiscal 2023.

The Company is eligible for an additional payment of $100.0 million upon achieving the first patient dosed in a Phase 3 trial. Furthermore, should the Phase 3 trial read out positively, and the potential new medicine receives regulatory approval in major markets, the deal provides for commercial milestone payments to the Company of up to $190.0 million at first commercial sale, and up to $590.0 million in sales-related milestone payments. The Company is further eligible to receive tiered royalties on net product sales in a range of mid-teens to twenty percent.

GSK-HBV Agreement

On December 11, 2023, the Company entered into an Amended and Restated License Agreement with GSK (the “GSK-HBV Agreement”) pursuant to which GSK received a worldwide, exclusive license to develop and commercialize daplusiran/tomligisiran (GSK5637608, formerly JNJ-3989), the Company’s third-generation subcutaneously administered RNAi therapeutic candidate being developed as a potential therapy for patients with chronic hepatitis B virus infection. GSK5637608 had previously been licensed to Janssen in October 2018.

Under the terms of the GSK-HBV Agreement, the Company received $2.7 million in December 2023, upon signing the amended GSK-HBV Agreement. The Company is eligible to receive up to $832.5 million in development and sales milestone payments under the GSK-HBV Agreement.

There were no contract assets and liabilities recorded as of June 30, 2024.

Horizon Therapeutics Ireland DAC (“Horizon”)

In June 2021, Horizon and the Company entered into a collaboration and license agreement (the “Horizon License Agreement”). Under the terms of the Horizon License Agreement, Horizon received a worldwide exclusive license for HZN-457, a clinical-stage medicine being developed by Horizon as a potential treatment for people with uncontrolled gout.

At the inception of the Horizon License Agreement, the Company identified one distinct performance obligation. The Company determined that the key deliverables included the license and certain R&D services, including the Company’s responsibilities to conduct all activities through the preclinical stages of development of HZN-457 (the “Horizon R&D Services”). The Company received a $40.0 million upfront payment in July 2021. Revenue was recognized on a straight-line basis over the timeframe for completing the Horizon R&D Services, concluding in the first quarter of 2023. Further, the Company received an additional $15.0 million upon Horizon’s initiation of a Phase 1 clinical trial in January 2023.

On October 6, 2023, Amgen completed its acquisition of Horizon and subsequently notified the Company of Amgen’s intent to terminate the HZN-457 license. Horizon exercised its right to terminate the Horizon License Agreement for convenience, which took effect on December 21, 2023.

Takeda Pharmaceutical Company Limited (“Takeda”)

In October 2020, Takeda and the Company entered into an Exclusive License and Co-Funding Agreement (the “Takeda License Agreement”). Under the Takeda License Agreement, Takeda and the Company will co-develop the Company’s fazirsiran program (formerly TAK-999 and ARO-AAT), the Company’s second-generation subcutaneously administered RNAi therapeutic candidate being developed as a treatment for liver disease associated with alpha-1 antitrypsin deficiency. Within the United States, fazirsiran, if approved, will be co-commercialized under a 50/50 profit sharing structure. Outside the United States, Takeda received an exclusive license to commercialize fazirsiran and will lead the global commercialization strategy, while the Company will be eligible to receive tiered royalties of 20% to 25% on net

sales.

At the inception of the Takeda License Agreement, the Company identified one distinct performance obligation. The Company determined that the key deliverables included the license and certain R&D services including the Company’s responsibilities to complete the initial portion of the SEQUOIA study, to complete the ongoing Phase 2 AROAAT2002 study and to ensure certain manufacturing of fazirsiran drug product is completed and delivered to Takeda (the “Takeda R&D Services”). Due to the specialized and unique nature of these Takeda R&D Services and their direct relationship with the license, the Company determined that these deliverables represent one distinct bundle and, thus, one performance obligation. Beyond the Takeda R&D Services, which are the responsibility of the Company, Takeda will be responsible for managing future clinical development and commercialization outside the United States. Within the United States, the Company will also participate in co-development and co-commercialization efforts and will co-fund these efforts with Takeda as part of the 50/50 profit sharing structure within the United States. The Company considers the collaborative activities, including the co-development and co-commercialization, to be a separate unit of account within Topic 808, and as such, these co-funding amounts are recorded as research and development expenses or general and administrative expenses, as appropriate.

Under the terms of the Takeda License Agreement, the Company received $300.0 million as an upfront payment in January 2021 and an additional $40.0 million upon Takeda’s initiation of a Phase 3 REDWOOD clinical study of fazirsiran in March 2023, and is eligible to receive up to $527.5 million in additional potential development, regulatory and commercial milestones.

The Company allocated the total $300.0 million initial transaction price to its one distinct performance obligation for the fazirsiran license and the associated Takeda R&D Services. Revenue was recognized using the input method (based on actual patient visits completed versus total estimated visits completed for the ongoing SEQUOIA and AROAAT2002 clinical studies). The Phase 2 study visits for patients in the SEQUOIA and AROAAT2002 studies concluded by December 31, 2023, and the Company has substantially completed its performance obligation under the Takeda License Agreement. As such, all revenue has been fully recognized as of December 31, 2023. There were no further deferred revenue and contract liabilities as of June 30, 2024.

The Company recorded $21.3 million as accrued expenses as of June 30, 2024 that was primarily driven by co-development and co-commercialization activities.

Janssen Pharmaceuticals, Inc. (“Janssen”)

On April 7, 2023, Janssen voluntarily terminated its collaboration agreement with the Company and the Company regained full rights to ARO-PNPLA3, formerly called JNJ-75220795. ARO-PNPLA3 is in Phase 1 clinical trials, which are now being developed by the Company.

Further, on December 11, 2023, the Company entered into the GSK-HBV Agreement, as discussed above, pursuant to which GSK received an exclusive license for daplusiran/tomligisiran (GSK5637608, formerly JNJ-3989). Daplusiran/tomligisiran had previously been licensed to Janssen in October 2018.

Amgen Inc. (“Amgen”)

In September 2016, Amgen and the Company entered into two collaboration and license agreements and a common stock purchase agreement. Under the Second Collaboration and License Agreement (the “Olpasiran Agreement”), Amgen received a worldwide, exclusive license to the Company’s novel RNAi olpasiran (previously referred to as AMG- 890 or ARO-LPA) program. These RNAi molecules are designed to reduce elevated lipoprotein(a), which is a genetically validated, independent risk factor for atherosclerotic cardiovascular disease. Under the Olpasiran Agreement, Amgen is wholly responsible for clinical development and commercialization.

Under the Olpasiran Agreement, the Company has received $35.0 million in upfront payments and $21.5 million in the form of an equity investment by Amgen in the Company’s common stock. Further, the Company received an additional $55.0 million in milestone payments; $10.0 million upon Amgen’s initiation of a Phase 1 study in September 2018, $20.0 million upon its initiation of a Phase 2 clinical study in July 2020, and $25.0 million upon its first subject enrollment in a Phase 3 trial in December 2022. The Company has substantially completed its performance obligations under the Olpasiran Agreement. There were no contract assets and liabilities recorded as of June 30, 2024.

In November 2022, Royalty Pharma Investments 2019 ICAV (“Royalty Pharma”) and the Company entered into a Royalty Purchase Agreement with Royalty Pharma (the “Royalty Pharma Agreement”). In consideration for the payments under the Royalty Pharma Agreement, Royalty Pharma is entitled to receive all royalties otherwise payable by Amgen to the Company under the Olpasiran Agreement. The Company remains eligible to receive up to an additional $485.0 million in remaining development, regulatory and sales milestone payments payable from Amgen and Royalty Pharma. See Note

11.

Visirna Therapeutics, Inc. (“Visirna”)

In April 2022, the Company and Visirna, its subsidiary, entered into a License Agreement (the “Visirna License Agreement”), pursuant to which Visirna received an exclusive license to develop, manufacture and commercialize four of the Company’s RNAi-based investigational cardiometabolic medicines in Greater China (including the People’s Republic of China, Hong Kong, Macau and Taiwan).

The Company also performs manufacturing and development work pursuant to a Clinical Supply Agreement between the parties contemplated by the Visirna License Agreement. The Company received $0.1 million and $0.9 million as consideration for this manufacturing and development work for the nine months ended June 30, 2024 and 2023, respectively. There were no contract assets and liabilities recorded as of June 30, 2024.

Organization and Significant Accounting Policies - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended
	Jan. 02, 2024	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Sep. 30, 2023
Organization And Significant Accounting Policies [Line Items]
Cash, cash equivalents and restricted cash		$ 69,400		$ 69,400
Restricted cash		2,200		2,200
Available-for-sale securities, at fair value		367,272		367,272		$ 292,735
Increase (decrease) in cash and investments				33,000
Development regulatory and sales milestones payments		2,700,000		2,700,000
Income tax expense (benefit)		0	$ 742	(3,313)	$ 759
Underwriting Agreement
Organization And Significant Accounting Policies [Line Items]
Net proceeds	$ 429,300
Shares of common stock issued (in shares)	15,790,000
Common stock offering price (in dollars per share)	$ 28.50
Aggregate purchase price paid by investors	$ 450,000
Amgen \| Royalty Pharma Agreement
Organization And Significant Accounting Policies [Line Items]
Milestone payment receivable upon achievement of enrollment in phase 3 clinical trial		$ 50,000		$ 50,000

Liability Related to the Sale of Future Royalties

9 Months Ended

Jun. 30, 2024

LIABILITY RELATED TO THE SALE OF FUTURE ROYALTIES

In November 2022, the Company and Royalty Pharma entered into the Royalty Pharma Agreement, pursuant to which Royalty Pharma agreed to pay up to $410.0 million in cash to the Company in consideration for the Company’s future royalty interest in olpasiran, a siRNA originally developed by the Company and licensed to Amgen in September 2016 under the Olpasiran Agreement.

Pursuant to the Royalty Pharma Agreement, Royalty Pharma paid $250.0 million upfront and agreed to pay up to an

additional $160.0 million in aggregate one-time milestone payments due if and when the following milestone events occur: (i) $50.0 million on completion of enrollment in the OCEAN Phase 3 clinical trial for olpasiran, (ii) $50.0 million upon receipt of FDA approval of olpasiran for an approved indication (reduction in the risk of myocardial infarction, urgent coronary revascularization, or coronary heart disease death in adults with established cardiovascular disease and elevated Lp(a)), and (iii) $60.0 million upon Royalty Pharma’s receipt of at least $70.0 million of royalty payments under the Royalty Pharma Agreement in any single calendar year. During the third quarter of fiscal 2024, Amgen completed enrollment of the Phase 3 OCEAN(a) outcomes trial of olpasiran, which triggered a $50.0 million milestone payment that the Company received in the same quarter.

In consideration for the payment of the foregoing amounts under the Royalty Pharma Agreement, Royalty Pharma is entitled to receive all royalties otherwise payable by Amgen to the Company under the Olpasiran Agreement. The Company remains eligible to receive any milestone payments potentially payable by Amgen under the Olpasiran Agreement.

The Company has evaluated the terms of the Royalty Pharma Agreement and concluded, in accordance with the relevant accounting guidance, that the Company accounted for the transaction as debt and the funding of $250.0 million and $50.0 million from Royalty Pharma were recorded as liabilities related to the sale of future royalties on its consolidated balance sheets. The Company is not obligated to repay these funds received under the Royalty Pharma Agreement.

The Company records the obligations at their carrying value using the effective interest method. In order to amortize the sale of future royalties, the Company utilizes the prospective method to estimate the future royalties to be paid by the Company to the counterparty over the life of the arrangement. Under the prospective method, a new effective interest rate is determined based on the revised estimate of remaining cash flows. The new rate is the discount rate that equates the present value of the revised estimate of remaining cash flows with the carrying amount of the debt, and it will be used to recognize non-cash interest expense for the remaining periods. The Company periodically assesses the amount and the timing of expected royalty payments using a combination of internal projections and forecasts from external sources. The estimates of future net product sales (and resulting royalty payments) are based on key assumptions including population, penetration, probability of success and sales price, among others. To the extent such payments are greater or less than the Company’s initial estimates or the timing of such payments is different than its original estimates, the Company will prospectively adjust the amortization of the royalty financing obligations and the effective interest rate. As of June 30, 2024, the estimated effective interest rate was 6.3%.

The following table presents the activity with respect to the liability related to the sale of future royalties.


	Carrying Amount
	(in thousands)
Carrying value as of September 30, 2023	$	268,326
Milestone payment received	50,000
Non-cash interest expense recognized	17,705
Carrying value as of June 30, 2024	$	336,031

Subsequent Events (Details) - Subsequent Event - Financing Agreement - Line of Credit $ in Millions	Aug. 07, 2024 USD ($)
Subsequent Event [Line Items]
Debt instrument term	7 years
Interest rate	15.00%
Secured Debt
Subsequent Event [Line Items]
Maximum borrowing capacity	$ 500.0
Long-term line of credit	400.0
Incremental Facility
Subsequent Event [Line Items]
Maximum borrowing capacity	$ 100.0

Fair Value Measurements - Fair Value Measurements for Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Jun. 30, 2024	Sep. 30, 2023
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	$ 367,272	$ 292,735
Cash equivalents	34,481	39,733
Total financial assets	401,753	332,468
Money market instruments
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	29,495	39,733
Commercial notes
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	4,986
U.S. government bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	80,946	31,553
Municipal securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities		7,093
Commercial notes
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	114,616	22,205
Corporate debt securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	171,710	231,884
Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	0	31,553
Cash equivalents	29,495	39,733
Total financial assets	29,495	71,286
Level 1 \| Money market instruments
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	29,495	39,733
Level 1 \| Commercial notes
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	0
Level 1 \| U.S. government bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	0	31,553
Level 1 \| Municipal securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities		0
Level 1 \| Commercial notes
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	0	0
Level 1 \| Corporate debt securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	0	0
Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	367,272	261,182
Cash equivalents	4,986	0
Total financial assets	372,258	261,182
Level 2 \| Money market instruments
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Level 2 \| Commercial notes
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	4,986
Level 2 \| U.S. government bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	80,946	0
Level 2 \| Municipal securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities		7,093
Level 2 \| Commercial notes
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	114,616	22,205
Level 2 \| Corporate debt securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	171,710	231,884
Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	0	0
Cash equivalents	0	0
Total financial assets	0	0
Level 3 \| Money market instruments
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Level 3 \| Commercial notes
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	0
Level 3 \| U.S. government bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	0	0
Level 3 \| Municipal securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities		0
Level 3 \| Commercial notes
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	0	0
Level 3 \| Corporate debt securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale securities	$ 0	$ 0

Commitments and Contingencies - Narrative (Details) ft² in Thousands	Jun. 30, 2024 USD ($)	Dec. 20, 2021 ft²
Other Commitments [Line Items]
Contingent liabilities	$ 0
Drug Manufacturing Facility \| Wisconsin
Other Commitments [Line Items]
Planned area of the site (in sq ft) \| ft²		160
Laboratory and Office Facility \| Wisconsin
Other Commitments [Line Items]
Planned area of the site (in sq ft) \| ft²		140
Facilities
Other Commitments [Line Items]
Capital expenditures incurred	266,000,000.0
Facilities \| Minimum
Other Commitments [Line Items]
Amount intends to invest for buildout of the facilities	18,000,000.0
Facilities \| Maximum
Other Commitments [Line Items]
Amount intends to invest for buildout of the facilities	$ 32,000,000.0

Collaboration and License Agreements - Amgen, Inc (Details)	1 Months Ended	9 Months Ended
	Sep. 30, 2016 USD ($) agreement	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)	Jul. 31, 2020 USD ($)	Sep. 30, 2018 USD ($)
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Proceeds from the issuance of common stock, net of offering costs		$ 429,265,000	$ 0
Contract liabilities		0		$ 866,000
Amgen \| Olpasiran Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of agreements \| agreement	2
Upfront payment	$ 35,000,000
Proceeds from the issuance of common stock, net of offering costs	$ 21,500,000
Milestone payments		55,000,000			$ 25,000,000	$ 20,000,000	$ 10,000,000
Contract assets		0
Contract liabilities		0
Amgen \| Olpasiran Agreement \| Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Additional remaining development regulatory and sales milestones payments		$ 485,000,000

Stockholders' Equity (Tables)

9 Months Ended

Jun. 30, 2024

Equity [Abstract]

Schedule of Shares of Common Stock and Preferred Stock

The following table summarizes the Company’s shares of common stock and preferred stock:


			Shares
	Par Value		Authorized	Issued	Outstanding
			(in thousands)
As of June 30, 2024
Common stock	$	0.001	290,000	124,227	124,227
Preferred stock	$	0.001	5,000	—	—

As of September 30, 2023
Common stock	$	0.001	290,000	107,312	107,312
Preferred stock	$	0.001	5,000	—	—

- Definition

Tabular disclosure of an entity's stock, including par or stated value per share, number and dollar amount of share subscriptions, shares authorized, shares issued, shares outstanding, number and dollar amount of shares held in an employee trust, dividend per share, total dividends, share conversion features, par value plus additional paid in capital, the value of treasury stock and other information necessary to a fair presentation, and EPS information. Stock by class includes common, convertible, and preferred stocks which are not redeemable or redeemable solely at the option of the issuer. Includes preferred stock with redemption features that are solely within the control of the issuer and mandatorily redeemable stock if redemption is required to occur only upon liquidation or termination of the reporting entity. If more than one issue is outstanding, state the title of each issue and the corresponding dollar amount; dollar amount of any shares subscribed but unissued and the deduction of subscriptions receivable there from; number of shares authorized, issued, and outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(27))
-SubTopic 10
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-3

Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-4

Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-5

Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481142/505-10-45-2

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-10

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-8

Reference 11: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480244/480-10-S99-1

Reference 12: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-6

Reference 13: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-7

+ Details

Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Income Statement [Abstract]
Revenue	$ 0	$ 15,825	$ 3,551	$ 224,638
Operating expenses:
Research and development	152,431	94,757	370,044	253,333
General and administrative	23,710	23,771	72,384	67,977
Total operating expenses	176,141	118,528	442,428	321,310
Operating loss	(176,141)	(102,703)	(438,877)	(96,672)
Other income (expense):
Interest income	6,498	4,172	15,550	11,414
Interest expense	(5,094)	(5,158)	(17,705)	(13,064)
Other, net	760	306	1,370	821
Total other income (expense)	2,164	(680)	(785)	(829)
Loss before income tax expense (benefit) and noncontrolling interest	(173,977)	(103,383)	(439,662)	(97,501)
Income tax expense (benefit)	0	742	(3,313)	759
Net loss including noncontrolling interest	(173,977)	(104,125)	(436,349)	(98,260)
Net loss attributable to noncontrolling interest, net of tax	(3,184)	(1,179)	(7,392)	(2,664)
Net loss attributable to Arrowhead Pharmaceuticals, Inc.	$ (170,793)	$ (102,946)	$ (428,957)	$ (95,596)
Net loss per share attributable to Arrowhead Pharmaceuticals, Inc.:
Basic (in dollars per share)	$ (1.38)	$ (0.96)	$ (3.63)	$ (0.90)
Diluted (in dollars per share)	$ (1.38)	$ (0.96)	$ (3.63)	$ (0.90)
Weighted-average shares used in calculating
Basic (in shares)	124,199	107,004	118,260	106,597
Diluted (in shares)	124,199	107,004	118,260	106,597
Other comprehensive loss, net of tax:
Change in unrealized losses on available-for-sale securities	$ 249	$ 0	$ 2,374	$ 0
Foreign currency translation adjustments	(141)	(79)	(139)	(275)
Comprehensive loss	$ (173,869)	$ (104,204)	$ (434,114)	$ (98,535)

Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Sep. 30, 2023
Finite Lived Intangible Assets [Line Items]
Net Carrying Amount	$ 8,987		$ 8,987		$ 10,262
Amortization expense	400	$ 400	1,300	$ 1,300
Novartis
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	24,857		24,857		24,857
Accumulated Amortization	15,870		15,870		14,595
Impairment	0		0		0
Net Carrying Amount	8,987		8,987		10,262
Novartis \| Patents
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	21,728		21,728		21,728
Accumulated Amortization	14,485		14,485		13,321
Impairment	0		0		0
Net Carrying Amount	$ 7,243		$ 7,243		$ 8,407
Useful Lives	14 years		14 years		14 years
Novartis \| License
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 3,129		$ 3,129		$ 3,129
Accumulated Amortization	1,385		1,385		1,274
Impairment	0		0		0
Net Carrying Amount	$ 1,744		$ 1,744		$ 1,855
Useful Lives	21 years		21 years		21 years

Net Loss Per Share - Antidulitive (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from computation of diluted earnings per share (in shares)	4,729	3,467	4,771	4,024
Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from computation of diluted earnings per share (in shares)	753	637	711	768
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from computation of diluted earnings per share (in shares)	3,976	2,830	4,060	3,256

Stock-Based Compensation - Narrative (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
	Oct. 01, 2023	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Sep. 30, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, share reserve for issuance (in shares)		4,565,727		4,565,727
Granted (in shares)				0
Stock-based compensation expense		$ 14,711	$ 19,947	$ 48,984	$ 59,949
Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Intrinsic value of options exercised		700	6,500	3,800	10,100
Stock-based compensation expense		400	2,100	2,500	6,700
Unrecognized pre-tax compensation expense		400		$ 400
Weighted average period to recognize pre-tax compensation expense				3 months
Restricted stock units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense		14,300	$ 17,800	$ 46,500	$ 53,200
Weighted average period to recognize pre-tax compensation expense				1 year 7 months 6 days
Unrecognized pre-tax compensation expense		$ 96,300		$ 96,300
2013 Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserve for issuance (in shares)		2,924,586		2,924,586
Number of shares forfeited (in shares)				158,928
2021 Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized (in shares)						8,000,000
Number of shares forfeited (in shares)				154,139
Granted (in shares)				3,697,189
Inducement Awards \| Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserve for issuance (in shares)		665,020		665,020
Inducement Awards \| Restricted stock units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserve for issuance (in shares)		616,638		616,638
Visirna ESOP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized (in shares)	20,000,000
Granted (in shares)	7,500,000
Stock-based compensation expense		$ 2,300		$ 5,500

Leases - Components of Lease Assets and Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Sep. 30, 2023
Lease Assets and Liabilities
Right-of-use assets	$ 44,339		$ 44,339		$ 45,297
Lease liabilities	6,053		6,053		10,563
Lease liabilities, net of current portion	112,040		112,040		$ 104,608
Lease Cost
Total	4,365	$ 4,089	12,513	$ 9,904
Research and development
Lease Cost
Operating lease cost	2,965	3,323	8,531	7,735
Variable lease cost	863	257	2,478	627
General and administrative expense
Lease Cost
Operating lease cost	537	509	1,504	1,542
Variable lease cost	$ 0	$ 0	$ 0	$ 0