Oruka Therapeutics (ORKA) 10-Q 13 Nov 24 2024 Q3 Quarterly report Financial data

Cover

Cover - shares	8 Months Ended
	Sep. 30, 2024	Oct. 31, 2024
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Entity Interactive Data Current	Yes
Amendment Flag	false
Document Period End Date	Sep. 30, 2024
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q3
Entity Information [Line Items]
Entity Registrant Name	Oruka Therapeutics, Inc.
Entity Central Index Key	0000907654
Entity File Number	000-22873
Entity Tax Identification Number	36-3855489
Entity Incorporation, State or Country Code	DE
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Contact Personnel [Line Items]
Entity Address, Address Line One	855 Oak Grove Avenue
Entity Address, Address Line Two	Suite 100
Entity Address, City or Town	Menlo Park
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94025
Entity Phone Fax Numbers [Line Items]
City Area Code	(650)
Local Phone Number	606-7910
Entity Listings [Line Items]
Title of 12(b) Security	Common stock, par value $0.001 per share
Trading Symbol	ORKA
Security Exchange Name	NASDAQ
Entity Common Stock, Shares Outstanding		34,998,550

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2024	Feb. 06, 2024
Current assets:
Cash and cash equivalents	$ 410,875
Subscription receivable		1
Prepaid expenses and other current assets	2,074
Total current assets	412,949	1
Property and equipment, net	160
Operating lease right-of-use asset	938
Other non-current assets	43
Total assets	414,090	1
Current liabilities:
Accounts payable	2,145
Accrued expenses and other current liabilities	1,710
Operating lease liability, current	146
Total current liabilities	18,039
Operating lease liability, non-current	842
Total liabilities	18,881
Commitment and contingencies (Note 11)
Stockholders’ equity:
Common stock, $0.001 and $0.0001 par value as of September 30, 2024 and February 6, 2024, respectively; 545,000,000 and 65,000,000 shares authorized, 34,998,550 and 3,197,975 shares issued and outstanding as of September 30, 2024 and February 6, 2024, respectively	35
Additional paid-in capital	397,345	1
Accumulated deficit	(57,943)
Total stockholders’ equity	342,368	1
Total liabilities, convertible preferred stock and stockholders’ equity	414,090	1
Related Party
Current liabilities:
Related party common stock warrant liability	7,681
Related party accounts payable and other current liabilities	6,357
Series A convertible preferred stock
Current liabilities:
Convertible preferred stock
Series A non-voting convertible preferred stock
Current liabilities:
Convertible preferred stock	52,841
Stockholders’ equity:
Series B non-voting convertible preferred stock, $0.001 par value; 251,504 and no shares authorized as of September 30, 2024 and February 6, 2024, respectively; 137,138 and no shares issued and outstanding as of September 30, 2024 and February 6, 2024, respectively	52,841
Series B Non-Voting Convertible Preferred Stock
Stockholders’ equity:
Series B non-voting convertible preferred stock, $0.001 par value; 251,504 and no shares authorized as of September 30, 2024 and February 6, 2024, respectively; 137,138 and no shares issued and outstanding as of September 30, 2024 and February 6, 2024, respectively	$ 2,931

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Unaudited) (Parentheticals) - USD ($) $ in Thousands	Sep. 30, 2024	Feb. 06, 2024
Common stock, par value (in Dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized	545,000,000	65,000,000
Common stock, shares issued	34,998,550	3,197,975
Common stock, shares outstanding	34,998,550	3,197,975
Series A convertible preferred stock
convertible preferred stock, par value (in Dollars per share)	$ 0.0001	$ 0.0001
convertible preferred stock, shares authorized		20,000,000
convertible preferred stock, shares issued
convertible preferred stock, shares outstanding
convertible preferred stock, liquidation preference (in Dollars)	$ 0	$ 0
Series A non-voting convertible preferred stock
convertible preferred stock, par value (in Dollars per share)	$ 0.001	$ 0.001
convertible preferred stock, shares authorized	2,439
convertible preferred stock, shares issued	2,439
convertible preferred stock, shares outstanding	2,439
Non-voting convertible preferred stock, shares authorized	2,439
Series B Non-Voting Convertible Preferred Stock
Non-voting convertible preferred stock, par value (in Dollars per share)	$ 0.001	$ 0.001
Non-voting convertible preferred stock, shares authorized	251,504
Non-voting convertible preferred stock, shares issued	137,138
Non-voting convertible preferred stock, shares outstanding	137,138

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands		3 Months Ended	8 Months Ended
		Sep. 30, 2024	Sep. 30, 2024
Operating expenses
Research and development	[1]	$ 25,691	$ 49,557
General and administrative	[2]	3,758	8,248
Total operating expenses		29,449	57,805
Loss from operations		(29,449)	(57,805)
Other income (expense)
Interest income		1,330	1,330
Interest expense	[3]	(504)	(1,468)
Total other income (expense), net		826	(138)
Net loss and comprehensive loss		$ (28,623)	$ (57,943)
Net loss per share attributable to stockholders, basic (in Dollars per share)		$ (1.46)	$ (6.08)
Net loss per share attributable to stockholders, diluted (in Dollars per share)		$ (1.46)	$ (6.08)
Weighted-average shares used in computing net loss per share attributable to stockholders, basic (in Shares)		15,013,655	7,765,381
Weighted-average shares used in computing net loss per share attributable to stockholders, diluted (in Shares)		15,013,655	7,765,381
Series A Non-Voting Convertible Preferred Stockholders
Other income (expense)
Net loss per share attributable to stockholders, basic (in Dollars per share)		$ (1,461.1)	$ (6,077.25)
Net loss per share attributable to stockholders, diluted (in Dollars per share)		$ (1,461.1)	$ (6,077.25)
Weighted-average shares used in computing net loss per share attributable to stockholders, basic (in Shares)		477	184
Weighted-average shares used in computing net loss per share attributable to stockholders, diluted (in Shares)		477	184
Series B Non-Voting Convertible Preferred Stockholders
Other income (expense)
Net loss per share attributable to stockholders, basic (in Dollars per share)		$ (121.76)	$ (506.44)
Net loss per share attributable to stockholders, diluted (in Dollars per share)		$ (121.76)	$ (506.44)
Weighted-average shares used in computing net loss per share attributable to stockholders, basic (in Shares)		49,191	19,015
Weighted-average shares used in computing net loss per share attributable to stockholders, diluted (in Shares)		49,191	19,015
[1] Includes related party amount of $13,537 for the three months ended September 30, 2024 and $33,967 for the period from February 6, 2024 (inception) to September 30, 2024 Includes related party amount of $71 for the three months ended September 30, 2024 and $1,339 for the period from February 6, 2024 (inception) to September 30, 2024 Includes related party amount of $504 for the three months ended September 30, 2024 and $1,468 for the period from February 6, 2024 (inception) to September 30, 2024

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) (Parentheticals) - USD ($) $ in Thousands	3 Months Ended	8 Months Ended
	Sep. 30, 2024	Sep. 30, 2024
Related party amount	$ 504	$ 1,468
Research and development
Related party amount	13,537	33,967
General and administrative
Related party amount	$ 71	$ 1,339

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Convertible Preferred Stock and Stockholders’ Equity (Deficit) (Unaudited) - USD ($) $ in Thousands	Convertible Preferred Stock Series A	Convertible Preferred Stock Series A Non-Voting	Convertible Preferred Stock Series B Non-Voting	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Series A Non-Voting	Total
Balances at Feb. 05, 2024				$ 3	$ (2)			$ 1
Balances (in Shares) at Feb. 05, 2024				3,197,975
Issuance of common stock				$ 2	(2)
Issuance of common stock (in Shares)				2,207,553
Issuance of Series A convertible preferred stock, net of issuance costs of $69	$ 2,931
Issuance of Series A convertible preferred stock, net of issuance costs of $69 (in Shares)	20,000,000
Stock-based compensation expense					17			17
Net loss						(7,077)		(7,077)
Balances at Mar. 31, 2024	$ 2,931			$ 5	13	(7,077)		(7,059)
Balances (in Shares) at Mar. 31, 2024	20,000,000			5,405,528
Balances at Feb. 05, 2024				$ 3	(2)			1
Balances (in Shares) at Feb. 05, 2024				3,197,975
Net loss								(57,943)
Balances at Sep. 30, 2024		$ 52,841	$ 2,931	$ 35	397,345	(57,943)		342,368
Balances (in Shares) at Sep. 30, 2024		2,439	137,138	34,998,550			2,439
Balances at Mar. 31, 2024	$ 2,931			$ 5	13	(7,077)		(7,059)
Balances (in Shares) at Mar. 31, 2024	20,000,000			5,405,528
Stock-based compensation expense					321			321
Net loss						(22,243)		(22,243)
Balances at Jun. 30, 2024	$ 2,931			$ 5	334	(29,320)		(28,981)
Balances (in Shares) at Jun. 30, 2024	20,000,000			5,405,528
Stock-based compensation expense					1,750			1,750
Exchange of Series A convertible preferred stock for Series B non-voting convertible preferred stock upon the closing of the reverse recapitalization	$ (2,931)		$ 2,931					2,931
Exchange of Series A convertible preferred stock for Series B non-voting convertible preferred stock upon the closing of the reverse recapitalization (in Shares)	(20,000,000)		137,138
Conversion of convertible notes (including accrued interest) into common stock upon the closing of the reverse recapitalization				$ 3	26,445			26,448
Conversion of convertible notes (including accrued interest) into common stock upon the closing of the reverse recapitalization (in Shares)				2,722,207
Issuance of common stock and pre-funded warrants in the Pre-Closing Financing,				$ 20	248,437			248,457
Issuance of common stock and pre-funded warrants in the Pre-Closing Financing, (in Shares)				20,061,932
Issuance costs of Pre-Closing Financing and reverse recapitalization					(20,480)			(20,480)
Issuance of common stock to former stockholders of ARCA biopharma, Inc. in connection with the closing of the reverse recapitalization				$ 1	4,999			5,000
Issuance of common stock to former stockholders of ARCA biopharma, Inc. in connection with the closing of the reverse recapitalization (in Shares)				1,208,883
Issuance of common stock, Series A non-voting convertible preferred stock, and pre-funded warrants in connection with the PIPE Financing		$ 56,097		$ 6	144,433			144,439
Issuance of common stock, Series A non-voting convertible preferred stock, and pre-funded warrants in connection with the PIPE Financing (in Shares)		2,439		5,600,000
Issuance cost of PIPE Financing		$ (3,256)			(8,573)			(8,573)
Net loss						(28,623)		(28,623)
Balances at Sep. 30, 2024		$ 52,841	$ 2,931	$ 35	$ 397,345	$ (57,943)		$ 342,368
Balances (in Shares) at Sep. 30, 2024		2,439	137,138	34,998,550			2,439

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Convertible Preferred Stock and Stockholders’ Equity (Deficit) (Unaudited) (Parentheticals) $ in Thousands	2 Months Ended
	Mar. 31, 2024 USD ($)
Statement of Stockholders' Equity [Abstract]
Issuance of Series A Convertible Preferred Stock, Net of Issuance Costs	$ 69

Condensed Consolidated Statem_5

Condensed Consolidated Statement of Cash flows (Unaudited) $ in Thousands	8 Months Ended
	Sep. 30, 2024 USD ($)
Cash flows from operating activities:
Net loss	$ (57,943)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation expense	11
Stock-based compensation expense	9,769
Non-cash interest expense	1,468
Non-cash lease expense	65
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(1,980)
Other non-current assets	(43)
Accounts payable	1,621
Accrued expenses and other current liabilities	1,650
Operating lease liability	6
Related party accounts payable and other current liabilities	6,357
Net cash used in operating activities	(39,019)
Cash flows from investing activities:
Purchases of property and equipment	(171)
Net cash used in investing activities	(171)
Cash flows from financing activities:
Proceeds from issuance of Pre-Merger Oruka Series A Preferred Stock, net of issuance costs paid	2,931
Proceeds from issuance of notes payable to related parties, net of issuance costs paid	24,980
Proceeds from the Pre-Closing Financing, net	228,127
Proceeds from the PIPE Financing, net	189,087
Cash acquired in connection with the reverse recapitalization	4,940
Net cash provided by financing activities	450,065
Net increase in cash and cash equivalents	410,875
Cash at beginning of period
Cash and cash equivalents at end of period	410,875
Supplemental disclosure of non-cash operating and financing activities:
Operating lease liability arising from obtaining operating right-of-use asset	982
Assets acquired in connection with the reverse recapitalization	114
Other liabilities assumed in connection with the reverse recapitalization	(54)
Pre-Closing Financing and reverse recapitalization issuance costs included in accounts payable	150
PIPE Financing issuance costs included in accounts payable	374
PIPE Financing issuance costs included in accrued expenses and other current liabilities	6
Non-cash accrued interest on convertible note converted to common stock	1,468
Non-cash exchange of Pre-Merger Oruka Series A Preferred Stock for Company Series B Convertible Preferred Stock	$ 2,931

Nature of the Business and Basi

Nature of the Business and Basis of Presentation	8 Months Ended
	Sep. 30, 2024
Nature of the Business and Basis of Presentation [Abstract]
Nature of the Business and Basis of Presentation	1. Nature of the Business and Basis of Presentation Background and Basis of Presentation Oruka Therapeutics, Inc., together with its subsidiaries (collectively, the “Company”), formerly known as ARCA biopharma, Inc. (“ARCA”), is an early-stage biotechnology company that is the result of the reverse recapitalization discussed below. Prior to the reverse recapitalization, the private company Oruka Therapeutics, Inc. (“Pre-Merger Oruka”) was established and incorporated under the laws of the state of Delaware on February 6, 2024 (referred to in the Notes as the inception of the Company). The Company is headquartered in Menlo Park, California. The Company is focused on developing biologics to optimize the treatment of inflammatory skin diseases. These condensed consolidated financial statements reflect, in the opinion of management, all adjustments of a normal and recurring nature that are necessary for a fair statement of the Company’s financial position as of September 30, 2024, and its results of operations for the three months ended September 30, 2024 and from February 6, 2024 (inception) to September 30, 2024, and cash flows for the period from February 6, 2024 (inception) to September 30, 2024. The condensed balance sheet as of February 6, 2024, included in the condensed consolidated balance sheets was derived from the Company’s audited financial statements. The condensed consolidated financial statements and accompanying notes are prepared in accordance with United States (“U.S.”) generally accepted accounting principles (“GAAP”) for interim financial reporting and the rules and regulations of the U.S. Securities and Exchange Commission (the “SEC”) and therefore do not include all information and disclosures normally included in the annual consolidated financial statements. The results for the three months ended September 30, 2024 and the period from February 6, 2024 (inception) to September 30, 2024 are not necessarily indicative of results expected for the full fiscal year or any subsequent interim period. The condensed consolidated financial statements include the financial statements of its wholly-owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. Reverse Recapitalization and Pre-Closing Financing On August 29, 2024, the Company consummated the previously announced business combination (“Closing”) pursuant to that certain Agreement and Plan of Merger and Reorganization, dated April 3, 2024 (the “Merger Agreement”), by and among ARCA, Atlas Merger Sub Corp, a wholly owned subsidiary of ARCA (“First Merger Sub”), Atlas Merger Sub II, LLC, a wholly owned subsidiary of ARCA (“Second Merger Sub”) and Pre-Merger Oruka, pursuant to which, among other matters, Pre-Merger Oruka merged with and into First Merger Sub, with Pre-Merger Oruka continuing as a wholly owned subsidiary of ARCA and the surviving corporation of the merger (“First Merger”) and following that, Pre-Merger Oruka then merged with and into Second Merger Sub, with Second Merger Sub being the surviving entity of the second merger (the “Second Merger” and together with the First Merger, the “Merger”). Following consummation of the Merger, the Company effected a 1-for-12 reverse stock split (the “Reverse Stock Split”) of the common stock, par value $0.001 per share, of the Company (“Company Common Stock”), which became effective on September 3, 2024. The Company Common Stock commenced trading on a post-Reverse Stock Split, post-Merger basis at the opening of trading on September 3, 2024. Second Merger Sub changed its corporate name to “Oruka Therapeutics Operating Company, LLC” and ARCA changed its name to “Oruka Therapeutics, Inc.” The Company is led by the Pre-Merger Oruka management team and remains focused on developing biologics to optimize the treatment of inflammatory skin diseases. Immediately prior to the execution and delivery of the Merger Agreement on April 3, 2024, certain new and existing investors of Pre-Merger Oruka entered into a subscription agreement with Pre-Merger Oruka (the “Subscription Agreement”), pursuant to which, and on the terms and subject to the conditions of which, immediately prior to the Closing, those investors purchased shares of common stock of Pre-Merger Oruka (“Pre-Merger Oruka Common Stock”) and Pre-Merger Oruka pre-funded warrants for gross proceeds of approximately $275.0 million (which includes $25.0 million of proceeds previously received from the issuance of the Convertible Note (as defined in Note 6) and accrued interest on such note which converted to shares of Pre-Merger Oruka Common Stock) (the “Pre-Closing Financing”). The Company incurred transaction costs of $20.5 million which was recorded as a reduction to additional paid-in capital in the unaudited condensed consolidated financial statements. At the Closing, the shares of Pre-Merger Oruka Common Stock and Pre-Merger Oruka pre-funded warrants issued pursuant to the Subscription Agreement were converted into shares of Company Common Stock and pre-funded warrants of Company Common Stock in accordance with the Exchange Ratio (defined below). In accordance with an Exchange Ratio determined by terms of the Merger Agreement and upon the effective time of the First Merger (the “First Effective Time”), (i) each then-issued and outstanding share of Pre-Merger Oruka Common Stock including outstanding and unvested Pre-Merger Oruka restricted stock and shares of Pre-Merger Oruka Common Stock issued in connection with the Subscription Agreement, were converted into the right to receive a number of shares of Company Common Stock, equal to the Exchange Ratio of 6.8569 shares of Company Common Stock, which were subject to the same vesting provisions as those immediately prior to the Merger, (ii) each share of Pre-Merger Oruka Series A convertible preferred stock, par value $0.0001 (“Pre-Merger Oruka Series A Preferred Stock”), outstanding immediately prior to the First Effective Time was converted into the right to receive a number of shares of ARCA Series B non-voting convertible preferred stock, par value $0.001 per share (“Company Series B Preferred Stock”), which are convertible into shares of Company Common Stock, at a conversion ratio of approximately 83:3332:1 (iii) each outstanding option to purchase Pre-Merger Oruka Common Stock was converted into an option to purchase shares of Company Common Stock, (iv) each outstanding warrant to purchase shares of Pre-Merger Oruka Common Stock was converted into a warrant to purchase shares of Company Common Stock, and (v) each share of Company Common Stock issued and outstanding at the First Effective Time remain issued and outstanding in accordance with its terms and such shares. Subsequent to the close of the merger, the common stock shares were then, subject to the reverse stock split of 1-for-12 effected on September 3, 2024. Net loss per share for periods prior to the close of the reverse recapitalization has been revised to reflect the exchange ratio. After applying the exchange ratio and the reverse stock split, net loss per share for the periods from February 6, 2024 (inception) to March 31, 2024 and for three months ended June 30, 2024 and from February 6, 2024 (inception) to June 30, 2024 are $(2.21), $(6.96), and $(9.17), respectively. As part of the Pre-Closing Financing and the Closing, investors in the Pre-Closing Financing received 22,784,139 shares of Company Common Stock in exchange for 39,873,706 shares of Pre-Merger Oruka Common Stock (which includes the issuance of 2,722,207 shares of Company Common Stock in exchange for 4,764,032 shares of Pre-Merger Oruka Common Stock on the conversion of Convertible Note along with the accrued interest through the conversion date) and 5,522,207 Company pre-funded warrants in exchange for 9,664,208 Pre-Merger pre-funded warrants. The Merger was accounted for as a reverse recapitalization in accordance with U.S. GAAP. Under this method of accounting, Pre-Merger Oruka was deemed to be the accounting acquirer for financial reporting purposes. This determination was primarily based on the fact that, immediately following the Merger: (i) Pre-Merger Oruka stockholders own a substantial majority of the voting rights in the combined company; (ii) Pre-Merger Oruka’s largest stockholders retain the largest interest in the combined company; (iii) Pre-Merger Oruka designated a majority of the initial members of the board of directors of the combined company; and (iv) Pre-Merger Oruka’s executive management team became the management team of the combined company. Accordingly, for accounting purposes: (i) the Merger was treated as the equivalent of Pre-Merger Oruka issuing stock to acquire the net assets of ARCA, and (ii) the reported historical operating results of the combined company prior to the Merger are those of Pre-Merger Oruka. Additional information regarding the Merger is included in Note 3. Reverse Stock Split On September 3, 2024, the Company effected the Reverse Stock Split, a 1-for-12 reverse stock split of Company Common Stock. The par value per share and the number of authorized shares were not adjusted as a result of the Reverse Stock Split. The shares of Company Common Stock underlying outstanding stock options, common stock warrants and other equity instruments were proportionately reduced and the respective exercise prices, if applicable, were proportionately increased in accordance with the terms of the agreements governing such securities. All references to common stock, options to purchase common stock, outstanding common stock warrants, common stock share data, per share data, and related information contained in the condensed consolidated financial statements have been retrospectively adjusted to reflect the effect of the Reverse Stock Split for all periods presented, unless otherwise specifically indicated or the context otherwise requires. PIPE Financing On September 11, 2024, the Company entered into a Securities Purchase Agreement for a private placement (the “PIPE Financing”) with certain institutional and accredited investors. The closing of the PIPE Financing occurred on September 13, 2024. Pursuant to the Securities Purchase Agreement, the investors purchased an aggregate of 5,600,000 shares of Company Common Stock at a purchase price of $23.00 per share, an aggregate of 2,439 shares of the Company’s Series A non-voting convertible preferred stock, par value $0.001 per share (“Company Series A Preferred Stock”), at a purchase price of $23,000.00 per share (each Company Series A Preferred Stock is convertible into 1,000 shares of Company Common Stock), and pre-funded warrants to purchase an aggregate of 680,000 shares of Company Common Stock at a purchase price of $22.999 per pre-funded warrant, for aggregate net proceeds of approximately $188.7 million (net of issuance costs of $11.8 million). Liquidity and Going Concern Since its inception, the Company has devoted substantially all of its resources to advancing the development of its portfolio of programs, organizing and staffing the Company, business planning, raising capital, and providing general and administrative support for these operations. Current and future programs will require significant research and development efforts, including preclinical and clinical trials, and regulatory approvals to commercialization. Until such time as the Company can generate significant revenue from product sales, if ever, the Company expects to finance its operating activities through a combination of equity offerings and debt financings. The Company has not generated any revenue from product sales or other sources and has incurred significant operating losses and negative cash flows from operations since inception. The Company has incurred a net loss of $28.6 million for the three months ended September 30, 2024 and $57.9 million during the period from February 6, 2024 (inception) to September 30, 2024. For the period from February 6, 2024 (inception) to September 30, 2024, the Company used net cash of $39.0 million for its operating activities. As of September 30, 2024, the Company had cash and cash equivalents of $410.9 million. The Company’s management expects that the existing cash and cash equivalents will be sufficient to fund the Company’s operating plans for at least twelve months from the date these condensed consolidated financial statements were issued. The Company expects that its research and development and general and administrative costs will continue to increase significantly, including in connection with conducting future pre-clinical activities and clinical trials and manufacturing for its existing product candidates and any future product candidates to support commercialization and providing general and administrative support for its operations, including the costs associated with operating as a public company. The Company’s ability to access capital when needed is not assured and, if capital is not available to the Company when, and in the amounts needed, the Company may be required to significantly curtail, delay or discontinue one or more of its research or development programs or the commercialization of any product candidate, or be unable to expand its operations or otherwise capitalize on the Company’s business opportunities, as desired, which could materially harm the Company’s business, financial condition and results of operations.

Summary of Significant Accounti

Summary of Significant Accounting Policies	8 Months Ended
	Sep. 30, 2024
Summary of Significant Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Use of Estimates The preparation of the Company’s condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates, assumptions, and judgments that affect the reported amounts of assets and liabilities and the disclosure of contingent liabilities at the date of the condensed consolidated financial statements and the reported amounts of income and expenses during the reporting periods. Significant estimates and assumptions reflected within these condensed consolidated financial statements include but are not limited to research and development expenses and related prepaid or accrued costs and the valuation of stock-based compensation awards and related expenses. The Company bases its estimates on known trends and other market-specific or other relevant factors that it believes to be reasonable under the circumstances. On an ongoing basis, management evaluates its estimates, as there are changes in circumstances, facts, and experience. Actual results could differ materially from those estimates or assumptions. Concentrations of Credit Risk and Other Risks and Uncertainties The Company’s cash and cash equivalents are maintained with financial institutions in the United States of America. Cash balances are held at financial institutions and account balances may exceed federally insured limits. To date, the Company has not experienced any losses on its cash and cash equivalents and periodically evaluates the creditworthiness of its financial institutions. The Company manages credit risk associated with its investment portfolio through its investment policy, which limits investments to high-quality issuers and limits the amount of its portfolio that can be invested in a single issuer. The Company is dependent on third-party organizations to research, develop, manufacture, and process its product candidates for its development programs, including its two most advanced programs, ORKA-001 and ORKA-002. The Company expects to continue to be dependent on a small number of manufacturers to supply it with its requirements for all products. The Company’s research and development programs could be adversely affected by a significant interruption in the supply of the necessary materials. A significant amount of the Company’s research and development activities are performed under its agreements with Paragon Therapeutics, Inc. (“Paragon”) (see Note 10). Cash and Cash Equivalents The Company considers all highly liquid investments with an original maturity of three months or less at the time of initial purchase to be cash equivalents. The cash equivalents were comprised of investments in money market funds. Debt Issuance Costs Debt issuance costs incurred in connection with the Convertible Note (see Note 6) are recorded as a reduction of the carrying value of the notes payable liability on the Company’s balance sheet and are amortized to interest expense over the term of the loan using the effective interest method. Subscription Receivable The Company accounts for any notes received in exchange for common stock as a subscription receivable, provided the note underlying the receivable is paid prior to the date the financial statement is available to be issued. Fair Value Measurements Certain assets and liabilities are carried at fair value under U.S. GAAP. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable: ● Level 1 — Quoted prices in active markets that are identical assets or liabilities. ● Level 2 — Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data. ● Level 3 — Unobservable inputs that are supported by little or no market activity that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies, and similar techniques. The Company’s cash equivalents are carried at fair value, determined according to the fair value hierarchy described above (see Note 4). The carrying values of the Company’s prepaid expenses and other current assets, accounts payable and accrued expenses and other current liabilities approximate their fair values due to their relatively short maturity period. Property and Equipment Property and equipment are stated at cost less accumulated depreciation. Depreciation expense is recognized using the straight-line method over the estimated useful life of each asset as follows: Estimated Useful Life Furniture and fixtures 3-5 years Computer and office equipment 3-5 years Classification of Convertible Preferred Stock Prior to the reverse recapitalization, the Company had classified its Pre-Merger Oruka Series A Preferred Stock outside of stockholders’ equity (deficit) on the Company’s condensed consolidated balance sheet because the holders of such stock have certain liquidation rights in the event of a deemed liquidation event that, in certain situations, is not solely within the control of the Company and would require the redemption of the then-outstanding convertible preferred stock. Upon the closing of the Merger, the Company converted its Pre-Merger Oruka Series A Preferred Stock to Company Series B Preferred Stock and has classified the Company Series B Preferred Stock within stockholders’ equity (deficit) on its condensed consolidated balance sheet because the Company Series B Preferred Stock is not redeemable or puttable to the Company by the holder under any circumstances. In connection with the PIPE Financing (see Note 1) the Company issued Company Series A Preferred Stock, and has classified the Company Series A Preferred Stock outside of stockholders’ equity (deficit) on the Company’s condensed consolidated balance sheet because the holders of such stock have certain rights (see Note 7) that, in certain situations, is not solely within the control of the Company and would require the redemption of the then-outstanding convertible preferred stock. Note Payable to Related Party The Company accounted for the Convertible Note (as defined in Note 6) at amortized cost. The Company considered if optional conversion features are required to be bifurcated and separately accounted for as a derivative. Costs related to the issuance of the Convertible Note were recorded as a debt discount, amortized over the term of the Convertible Note (see Note 6) and were accounted as interest expense in other income (expenses) within the condensed consolidated statements of operations and comprehensive loss using the effective interest method. At the effective time of the Merger, shares of Pre-Merger Oruka Common Stock issued pursuant to the conversion of the Convertible Note (including accrued interest) automatically converted into shares of Company Common Stock (see Note 1). Research and Development Contract Costs Accruals The Company records the costs associated with research studies and manufacturing development as incurred. These costs are a significant component of the Company’s research and development expenses, with a substantial portion of the Company’s ongoing research and development activities conducted by third-party service providers, including contract research organizations (“CROs”) and contract manufacturing organizations (“CMOs”), and the Company’s related-party Paragon (see Note 10). The Company accrues for expenses resulting from obligations under its two antibody discovery and option agreements (the “Option Agreements”) (see Note 10), by and among Paragon, Paruka Holding LLC (“Paruka”), an entity formed by Paragon as a vehicle to hold equity in the Company, and the Company as well as agreements with CROs, CMOs, and other outside service providers for which payment flows do not match the periods over which materials or services are provided to the Company. Accruals are recorded based on estimates of services received and efforts expended pursuant to agreements established with Paragon, CROs, CMOs, and other outside service providers. These estimates are typically based on contracted amounts applied to the proportion of work performed and determined through analysis with internal personnel and external service providers as to the progress or stage of completion of the services. The Company makes significant judgments and estimates in determining the accrual balance in each reporting period. If advance payments are made to Paragon, a CRO, CMO, or outside service provider, the payments will be recorded as a prepaid asset which will be expensed as the contracted services are performed. Changes in these estimates that result in material changes to the Company’s accruals could materially affect the Company’s results of operations. As of September 30, 2024, the Company has not experienced any material deviations between accrued and actual research and development expenses. Leases At the lease commencement date, when control of the underlying asset is transferred from the lessor to the Company, the Company classifies a lease as either an operating or finance lease and recognizes a right-of-use (“ROU”) asset and a current and non-current lease liability, as applicable, in the balance sheet if the lease has a term greater than one year. Lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise its option. At the lease commencement date, operating lease liabilities and their corresponding ROU assets are recorded at the present value of future minimum lease payments over the expected remaining lease term. The Company determines the present value of lease payments using the implicit rate, if it is readily determinable, or the risk-free discount rate for a period comparable with that of the lease term. For operating leases, lease expense for lease payments is recognized on a straight-line basis over the lease term. For finance leases, lease expense includes amortization expense of the ROU asset recognized on a straight-line basis over the lease term and interest expense recognized on the finance lease liability. In addition, certain adjustments to the ROU asset may be required for items such as lease prepayments, incentives received or initial direct costs. As of September 30, 2024, the Company has one operating lease and no finance leases. The Company accounts for lease and non-lease components related to operating leases as a single lease component. The Company has elected that costs associated with leases having an initial term of 12 months or less are recognized in the condensed consolidated statement of operations and comprehensive loss on a straight-line basis over the lease term and are not recorded on its condensed consolidated balance sheets. Variable lease expense is recognized as incurred and consists primarily of real estate taxes, utilities, and other office space related expenses. Segment Reporting The Company operates and manages its business as a single segment for the purposes of assessing performance and making operating decisions. The Company’s chief executive officer, who is the chief operating decision maker (the “CODM”), reviews the Company’s financial information on an aggregated basis for purposes of evaluating financial performance and allocating resources. Research and Development Costs Research and development costs are expensed as incurred. Research and development costs include salaries and bonuses, stock-based compensation, employee benefits, and external costs of vendors and consultants engaged to conduct research and development activities, as well as allocated human resource costs, information technology costs, and facility-related costs, including rent, maintenance, utilities, and depreciation. Nonrefundable advance payments for goods or services to be received in the future for use in research and development activities are recorded as prepaid expenses on the accompanying condensed consolidated balance sheet. The prepaid amounts are expensed as the related goods are delivered or the services are performed, or when it is no longer expected that the goods will be delivered, or the services rendered. If nonrefundable advance payments represent a one-time cost for obtaining goods or services, with anticipated benefits to be utilized within a year of period end, the payment is expensed immediately. General and Administrative Expenses General and administrative expenses consist primarily of salaries and bonuses, stock-based compensation, employee benefits, finance and administration costs, patent and intellectual property costs, professional fees, as well as allocated human resource costs, information technology costs, and facility-related costs, including rent, maintenance, utilities and depreciation. Commitments and Contingencies The Company is subject to contingent liabilities, such as legal proceedings and claims, that arise in the ordinary course of business activities. The Company accrues for loss contingencies when losses become probable and are reasonably estimable. If the reasonable estimate of the loss is a range and no amount within the range is a better estimate, the minimum amount of the range is recorded as a liability on the balance sheet. The Company does not accrue for contingent losses that, in its judgment, are considered to be reasonably possible, but not probable; however, it discloses the range of reasonably possible losses. As of September 30, 2024, no liabilities were recorded for loss contingencies (see Note 11). Stock-Based Compensation The Company measures all stock-based awards granted to employees, directors, and non-employees in the form of stock options to purchase shares of its common stock, based on the fair value of the awards on the date of grant using the Black-Scholes option-pricing model. The Company measures restricted common stock awards (“RSAs”) using the difference, if any, between the purchase price per share of the award and the fair value of the Company’s common stock at the date of grant. The Company grants stock options, restricted stock awards, and warrants that are subject to service or performance-based vesting conditions. Compensation expense for awards to employees and directors with service-based vesting conditions is recognized using the straight-line method over the requisite service period, which is generally the vesting period of the respective award. Compensation expense for awards to non-employees with service-based vesting conditions is recognized in the same manner as if the Company had paid cash in exchange for the goods or services, which is generally over the vesting period of the award. Forfeitures are accounted for as they occur. As of each reporting date, the Company estimates the probability that specified performance criteria will be met and does not recognize compensation expense until it is probable that the performance-based vesting condition will be achieved. The Company has issued stock options, warrants, and RSAs with service-based and performance-based vesting conditions. The Company recognizes the compensation expense for the option to purchase common stock under the Employee Stock Purchase Plan (“ESPP”), based on the fair value of the common stock estimated using the closing price of the Company’s common stock as reported on the date of offering, less the purchase discount percentage provided for in the plan. The Company classifies stock-based compensation expense in its condensed consolidated statement of operations and comprehensive loss in the same manner in which the award recipient’s payroll costs are classified or in which the award recipient’s service payments are classified. Net Loss per Share Attributable to Stockholders Basic and diluted net loss attributable to stockholders per share is presented in conformity with the two-class method required for participating securities (Pre-Merger Oruka Series A Preferred Stock). Basic earnings per share is computed by dividing net income available to each class of shares by the weighted-average number of shares of common stock and participating securities outstanding during the period. Pre-funded warrants were included as the exercise price is negligible and these warrants are fully vested and exercisable. Company Series A Preferred Stock and Company Series B Preferred Stock share the same characteristics as Common Stock and have no substantive preference attributed to them and, accordingly, have been considered as classes of Common Stock in the computation of net loss per share regardless of their legal form. Net loss is allocated to common stock based on its proportional ownership on an as-converted basis. Net loss is not allocated to participating securities as they do not have an obligation to fund losses. The weighted-average number of shares outstanding of common stock reflects changes in ownership over the periods presented. See Note 7— Convertible Preferred Stock and Stockholders’ Equity. Diluted net loss per share is computed by dividing the net loss attributable to stockholders adjusted for income (expenses), net of tax, related to any diluted securities, by the weighted-average number of shares of common stock and potentially dilutive securities outstanding for the period. For purposes of this calculation, stock options to purchase common stock, employee warrants to purchase common stock, and unvested RSAs are considered potential dilutive common shares. The Company generated a net loss for the periods presented. Accordingly, basic and diluted net loss per share is the same because the inclusion of the potentially dilutive securities would be anti-dilutive. Income Taxes The Company accounts for income taxes using the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the financial statements or in the Company’s tax returns. Deferred tax assets and liabilities are determined based on the differences between the financial statement basis and tax basis of assets and liabilities using enacted tax rates in effect for the years in which the differences are expected to reverse. Changes in deferred tax assets and liabilities are recorded in the provision for income taxes. The Company assesses the likelihood that its deferred tax assets will be recovered from future taxable income and, to the extent it believes, based upon the weight of available evidence, that it is more likely than not that all or a portion of the deferred tax assets will not be realized, a valuation allowance is established through a charge to income tax expense. The potential for recovery of deferred tax assets is evaluated by estimating the future taxable profits expected and considering prudent and feasible tax planning strategies. The Company accounts for uncertainty in income taxes recognized in the condensed consolidated financial statements by applying a two-step process to determine the amount of tax benefit to be recognized. First, the tax position must be evaluated to determine the likelihood that it will be sustained upon external examination by the taxing authorities. If the tax position is deemed more likely than not to be sustained, the tax position is then assessed to determine the amount of benefit to recognize in the condensed consolidated financial statements. The amount of the benefit that may be recognized is the largest amount that has a greater than 50% likelihood of being realized upon ultimate settlement. The provision for income taxes includes the effects of any resulting tax reserves, or unrecognized tax benefits, that are considered appropriate as well as the related net interest and penalties. The Company had accrued no amounts for interest or penalties related to uncertain tax positions as of September 30, 2024. Recently Issued Accounting Pronouncements In November 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2023-07, Segment Reporting Topic 280 : Improvements to Reportable Segment Disclosures In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures In November 2024, the FASB issued ASU 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses

Reverse Recapitalization and Pr

Reverse Recapitalization and Pre-Closing Financing	8 Months Ended
	Sep. 30, 2024
Reverse Recapitalization and Pre-Closing Financing [Abstract]
Reverse Recapitalization and Pre-Closing Financing	3. Reverse Recapitalization and Pre-Closing Financing As described within the Reverse Recapitalization and Pre-Closing Financing As part of the recapitalization, the Company acquired the assets and liabilities listed below (in thousands): Amount Cash and cash equivalents $ 4,940 Other current assets 114 Accrued liabilities (54 ) Net assets acquired $ 5,000

Fair Value Measurements

Fair Value Measurements	8 Months Ended
	Sep. 30, 2024
Fair Value Measurements [Abstract]
Fair Value Measurements	4. Fair Value Measurements The following tables present the Company’s fair value hierarchy for financial assets measured as of September 30, 2024 (in thousands): Fair Value Measurements as of September 30, 2024 Level 1 Level 2 Level 3 Total Financial assets: Money market funds $ 403,322 $ — $ — $ 403,322 Total financial assets $ 403,322 $ — $ — $ 403,322 There were no transfers between Level 1, Level 2, or Level 3 during the period from February 6, 2024 (inception) to September 30, 2024.

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	8 Months Ended
	Sep. 30, 2024
Accrued Expenses and Other Current Liabilities [Abstract]
Accrued Expenses and Other Current Liabilities	5. Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consisted of the following (in thousands): September 30, Accrued employee compensation and benefits $ 933 Accrued professional and consulting 204 Accrued research and development 573 $ 1,710

Note Payable with Related Party

Note Payable with Related Party	8 Months Ended
	Sep. 30, 2024
Note Payable with Related Party [Abstract]
Note Payable with Related Party	6. Note Payable with Related Party In March 2024, the Company entered into a Series A Preferred Stock and Convertible Note Purchase Agreement (the “Purchase Agreement”) with Fairmount Healthcare Fund II, L.P. (“Fairmount”), whereby the Company issued a convertible note (the “Convertible Note”), with an initial principal amount of $25.0 million that, at the time of issuance, could be converted into Pre-Merger Oruka Series A Preferred Stock (or a series of preferred shares that is identical in respect to the shares of preferred shares issued in its next equity financing) or shares of Pre-Merger Oruka Common Stock in exchange for aggregate proceeds of $25.0 million. The Convertible Note accrued interest at a rate of 12.0% per annum. At issuance, the Convertible Note required all unpaid interest and principal to mature on December 31, 2025 (the “Maturity Date”) and prepayment was not permitted without prior written consent of Fairmount. At issuance, the principal payment along with the accrued interest on the Convertible Note was due in full on the Maturity Date. The Company assessed all terms and features of the Convertible Note in order to identify any potential embedded features that would require bifurcation. As part of this analysis, the Company assessed the economic characteristics and risks of the embedded features. The Company determined that the share settled redemption feature was clearly and closely related to the debt host and did not require separate accounting. The Company determined that the conversion options of the Convertible Note were not clearly and closely associated with a debt host. However, these features did not meet the definition of a derivative under ASC 815, Derivatives and Hedging The Company paid debt issuance costs of less than $0.1 million in relation to the Convertible Note. The debt issuance costs were reflected as a reduction of the carrying value of Convertible Note on the condensed consolidated balance sheet and were being amortized as interest expense over the term of the Convertible Note using the effective interest method. For the three months ended September 30, 2024 and the period from February 6, 2024 (inception) to September 30, 2024, the Company recognized interest expenses related to the Convertible Note of $0.5 million and $1.5 million, respectively, which includes non-cash interest expense related to the amortization of debt issuance. Immediately prior to the completion of the Merger (see Note 1), the Convertible Note was converted into shares of Pre-Merger Oruka Common Stock based on the aggregate principal amount of $25.0 million, plus unpaid accrued interest of $1.5 million divided by the conversion price which was determined based upon the Company’s fully-diluted capitalization immediately prior to the Merger. At the effective time of the Merger, the Pre-Merger Oruka Common Stock issued upon the conversion of the Convertible Note (including accrued interest) automatically converted into 2,722,207 shares of Company Common Stock. As of September 30, 2024, the Convertible Note is not outstanding.

Convertible Preferred Stock and

Convertible Preferred Stock and Stockholders’ Equity	8 Months Ended
	Sep. 30, 2024
Convertible Preferred Stock and Stockholders’ Equity [Abstract]
Convertible Preferred Stock and Stockholders’ Equity	7. Convertible Preferred Stock and Stockholders’ Equity Pre-Funded Warrants In August 2024, pursuant to the Subscription Agreement and immediately prior to the Closing, certain new and current investors purchased pre-funded warrants, which, at the effective time of the Merger, were exercisable for 5,522,207 shares of Company Common Stock at a purchase price of approximately $9.70 per warrant. After the Merger, there are 5,522,207 pre-funded warrants outstanding and are exercisable for 5,522,207 shares of the Company Common Stock at an exercise price of $0.01 per share. In September 2024, in connection with the PIPE Financing, the Company issued and sold 680,000 pre-funded warrants, at a purchase price of $22.999 per warrant, exercisable for 680,000 shares of Company Common Stock at an exercise price of $0.001 per share. The pre-funded warrants were recorded as a component of stockholders’ equity within additional paid-in-capital and have no none Employee Warrants In July 2024, Pre-Merger Oruka entered into a Subscription Agreement that provided for, among other things, the issuance of warrants to certain of Pre-Merger Oruka’s employees, directors, and service providers immediately prior to the closing of the Merger. During the three months ended September 30, 2024, 3,054,358 employee warrants were issued at an exercise price of $7.80 per warrant. These employee warrants vest over a period of four years. Per the terms of the Employee Warrant Agreement, the holders of the Company’s employee warrants shall not have any of the rights or privileges of a stockholder of the Company in respect of any shares purchasable upon the exercise of the warrant or any portion thereof unless and until a certificate or certificates representing such shares have been issued or a book entry representing such shares has been made and such shares have been deposited with the appropriate registered book-entry custodian. The Company recognizes compensation cost related to employee warrants on a straight-line basis over the requisite service period, which is the period in which the related services are received. As of September 30, 2024, none Convertible Preferred Stock In March 2024, Pre-Merger Oruka issued and sold an aggregate of 20,000,000 shares of Pre-Merger Oruka Series A Preferred Stock to Fairmount (see Note 13), at a purchase price of approximately $0.15 per share, for aggregate gross proceeds of $3.0 million. Pre-Merger Oruka incurred less than $0.1 million of issuance costs in connection with this transaction. Upon the issuance of the Pre-Merger Oruka Series A Preferred Stock, the Company assessed the embedded conversion and liquidation features of the securities as described below and determined that such features did not require the Company to separately account for these features. In August 2024, upon the closing of the Merger, the Company converted the Pre-Merger Oruka Series A Preferred Stock to 137,138 shares of Company Series B Preferred Stock. In September 2024, in connection with the PIPE Financing, the Company issued and sold an aggregate of 2,439 shares of the Company Series A Preferred Stock at a purchase price of $23,000.00 per share. As of September 30, 2024, convertible preferred stock consisted of the following (in thousands, except share data): September 30, 2024 Preferred Stock Preferred Stock Carrying Common Stock Series A Non-Voting Preferred Stock 2,439 2,439 $ 52,841 2,439,000 Series B Non-Voting Preferred Stock 251,504 137,138 $ 2,931 11,428,149 Pursuant to the Certificate of Designation of Preferences, Rights and Limitations of the Series A Non-Voting Convertible Preferred Stock (the “Series A Certificate of Designation”) filed in connection with the PIPE Financing, holders of Company Series A Preferred Stock are entitled to receive dividends on shares of Company Series A Preferred Stock equal to, on an as-if-converted-to-Company Common Stock basis, and in the same form as, dividends actually paid on shares of Company Common Stock. Except as provided in the Series A Certificate of Designation or as otherwise required by law, the Company Series A Preferred Stock does not have voting rights. The Company Series A Preferred Stock shall rank on parity with the Company Common Stock and Company Series B Preferred Stock upon any liquidation, dissolution or winding-up of the Company. Subject to the terms and limitations contained in the Series A Certificate of Designation, the Company Series A Preferred Stock issued in the PIPE Financing will not become convertible until the Company’s stockholders approve the conversion of the Company Series A Preferred Stock into shares of Company Common Stock in accordance with the listing rules of the Nasdaq Stock Market (the “Stockholder Approval”), which resulted in the Company Series A Preferred Stock being classified outside of stockholders’ equity (deficit) on the Company’s condensed consolidated balance sheet. Following the Stockholder Approval, each share of Company Series A Preferred Stock will automatically convert into 1,000 shares of Company Common Stock, subject to certain limitations, including that shares of Company Series A Preferred Stock shall not be convertible if the conversion would result in a holder, together with its affiliates, beneficially owning more than 9.99% of the Company’s outstanding shares of Company Common Stock as of the applicable conversion date, which may be increased at the holders’ option (not to exceed 19.99%), effective in accordance with the terms of the Series A Certificate of Designation. If, at any time after the earlier of Stockholder Approval or six months after the initial issuance of the Series A non-voting preferred stock, the Company fails to deliver to a holder such certificate or certificates, the Company shall, at the request of the holder, pay an amount equal to the closing price of Company’s common stock on the trading day immediately prior to the date on which notice to conversion is received by the Company (the “Fair Value”) of such undelivered shares, with such payment to be made within two business days from the date of request by the holder, whereupon the Company’s obligations to deliver such shares underlying the notice of conversion shall be extinguished upon payment in full of the Fair Value of such undelivered shares; provided, however that such request shall be presumed to have been made by such holder if Stockholder Approval shall not have been obtained prior to the date on which the notice of conversion is delivered to the Company. Pursuant to the Certificate of Designation of Preferences, Rights and Limitations of the Series B Non-Voting Convertible Preferred Stock (the “Series B Certificate of Designation”) filed in connection with the Merger, holders of Company Series B Preferred Stock are entitled to receive dividends on shares of Company Series B Preferred Stock equal to, on an as-if-converted-to-Company Common Stock basis, and in the same form as, dividends actually paid on shares of Company Common Stock. Except as provided in the Series B Certificate of Designation or as otherwise required by law, the Company Series B Preferred Stock does not have voting rights. The Company Series B Preferred Stock shall rank on parity with the Company Common Stock as to the distribution of assets upon any liquidation, dissolution, or winding-up of the Company. Each share of Company Series B Preferred Stock is convertible at the option of the holder, at any time, and without the payment of additional consideration by the holder. As of September 30, 2024, each outstanding share of Company Series B Preferred Stock was convertible into common stock at a ratio of approximately 83.3332:1. Common Stock As of September 30, 2024, the Certificate of Incorporation provides for 545,000,000 authorized shares of Company Common Stock. As of September 30, 2024, 34,988,550 shares of Company Common Stock were issued and outstanding, including 2,207,553 shares of RSAs issued and outstanding. As of September 30, 2024, the Company had common stock reserved for future issuance as follows: September 30, Shares issuable on conversion of Company Series A Preferred Stock 2,439,000 Shares issuable on conversion of Company Series B Preferred Stock 11,428,149 Shares issuable upon exercise of pre-funded warrants 6,202,207 Outstanding and issued stock options 1,287,760 Outstanding and issued employee warrants 3,054,358 Shares available for grant under 2024 Stock Incentive Plan 4,526,324 Shares available for grant under 2024 Employee Stock Purchase Plan 463,489 Total shares of common stock reserved 29,401,287

Stock-Based Compensation

Stock-Based Compensation	8 Months Ended
	Sep. 30, 2024
Stock-Based Compensation [Abstract]
Stock-Based Compensation	8. Stock-Based Compensation 2024 Equity Incentive Plan The 2024 Equity Incentive Plan (“2024 Plan”) was adopted by the board of directors of Pre-Merger Oruka on February 6, 2024. The 2024 Plan provided for Pre-Merger Oruka to grant stock options, restricted stock awards, restricted stock units, and other stock-based awards to employees, officers, directors, consultants, and advisors. Equity Incentive Stock options granted under the 2024 Plan generally vest over four years, subject to the participant’s continued service, and expire after ten years, although stock options have been granted with vesting terms less than four years. As of September 30, 2024, there are no shares of common stock available for issuance. 2024 Stock Incentive Plan On August 22, 2024, the 2024 Stock Incentive Plan (“2024 Stock Plan”) was approved by the Company’s stockholders and on August 29, 2024, the board of directors of the Company (the “Board”) ratified the 2024 Stock Plan. The 2024 Stock Plan allows for the grant of stock options, stock appreciation rights, restricted stock awards, restricted stock units, other stockholder-based awards and incentive bonuses. The 2024 Stock Plan is administered by the Compensation Committee of the Board (the “Compensation Committee”) or another committee designated by the Board to administer the Plan. The initial share pool under the 2024 Stock Plan is 4,634,891 shares of Company Common Stock and as of September 30, 2024, there are 4,526,324 shares available in the pool. The shares that may be issued under the 2024 Stock Plan will be automatically increased on January 1 of each year beginning in 2025 and ending with a final increase on January 1, 2034 in an amount equal to 5% of the diluted stock (including Company Common Stock, preferred stock and unexercised pre-funded warrants) on the preceding December 31, unless a lower, or no, increase is determined by the Compensation Committee. Current or prospective employees, officers, non-employee directors, and other independent service providers of the Company and its subsidiaries are eligible to participate in the 2024 Stock Plan. 2024 Employee Stock Purchase Plan The 2024 Employee Stock Purchase Plan (the “ESPP”) was approved by the board of directors of ARCA on July 20, 2024, and by ARCA’s stockholders on August 22, 2024. The ESPP became effective on August 29, 2024, at which time 463,489 shares were reserved for issuance. The shares that may be issued under the ESPP will be automatically increased on January 1 of each year beginning in 2025 and ending with a final increase on January 1, 2034 in an amount equal to 1% of the diluted stock (including Company Common Stock, preferred stock and unexercised pre-funded warrants) on the preceding December 31, unless a lower, or no, increase is determined by the Compensation Committee. As of September 30, 2024, no shares have been issued out of the ESPP. Stock Option Valuation The following table summarizes the weighted-average assumptions used in calculating the fair value of the awards for the three months ended September 30, 2024 and for the period from February 6, 2024 (inception) to September 30, 2024: Three Period from Expected term (in years) 6.1 6.1 Expected volatility 97.3 % 101.0 % Risk-free interest rate 3.5 % 4.3 % Expected dividend yield — % — % Stock Options The following table summarizes the stock option activities under the 2024 Plan and 2024 Stock Plan for the period of February 6, 2024 (inception) through September 30, 2024: Number of Weighted Weighted Aggregate Balance as of February 6, 2024 (inception) — $ — — $ — Granted 1,287,760 $ 7.97 Exercised — $ — Forfeited — $ — Balance as of September 30, 2024 1,287,760 $ 7.97 9.6 $ 21,507 Vested and expected to vest, September 30, 2024 1,287,760 $ 7.97 9.6 $ 21,507 Exercisable, September 30, 2024 — $ — — $ — The weighted average grant-date fair value per share of stock options granted during the period from February 6, 2024 (inception) to September 30, 2024 was $6.44 per share. Aggregate intrinsic value represents the difference between the estimated fair value of the underlying Company Common Stock and the exercise price of outstanding, in-the-money employee stock options. Restricted Stock Awards In February 2024 and March 2024, the Company issued 2,207,553 shares of RSAs to certain employees, directors, and consultants at a price of $0.0001 per share, the then par value of Pre-Merger Oruka Common Stock. Such RSAs have service-based vesting conditions only and vest over a four-year period, during which time all unvested shares are subject to forfeiture in the event the holder’s service with the Company voluntarily or involuntarily terminates. The following table summarizes the RSAs activity for the period from February 6, 2024 (inception) through September 30, 2024: Number of Weighted Unvested balance as of February 6, 2024 (inception) — $ — Granted 2,207,553 — Unvested balance as of September 30, 2024 2,207,553 $ — Option Agreements and Paruka Warrant Obligation In March 2024, the Company entered into antibody discovery and option agreements with Paragon and Paruka (the “Option Agreements”). Under the terms of Option Agreements, Paragon identifies, evaluates, and develops antibodies directed against certain mutually agreed therapeutic targets of interest to the Company, and the Company has the exclusive option to, on a research program-by-research program basis, be granted an exclusive, worldwide license to all of Paragon’s right, title, and interest in and to the intellectual property resulting from the applicable research program to develop, manufacture and commercialize the antibodies and products directed to the selected target(s). Paruka will be entitled to grants of warrants to purchase a number of shares equal to 1.00% of then outstanding shares of the Company’s stock, on a fully diluted basis, on December 31, 2024 and December 31, 2025, at the fair market value determined by the Board (the “Paruka Warrant Obligation”). The grant dates for the issuance of warrants are expected to be December 31, 2024 and December 31, 2025 as all terms of the award, including number of shares and exercise price, will be known by all parties. The service inception period for the grant precedes the grant date, with the full award being vested as of the grant date with no post-grant date service requirement. Accordingly, the warrants expected to be granted to Paruka were accounted for as a liability on the condensed balance sheet and, after the initial recognition, the liability is adjusted to fair value at the end of each reporting period, with changes in fair value recorded in the statement of operations and comprehensive loss as stock-based compensation expenses under research and development expenses. As of September 30, 2024, the estimated fair value of warrants to be granted on December 31, 2024 was $11.0 million. For the three months ended September 30, 2024 and the period from February 6, 2024 (inception) to September 30, 2024, $7.3 million and $7.7 million were recognized as stock-based compensation expenses related to the Paruka Warrant Obligation, respectively. Employee Warrants As stated above, on July 3, 2024, the Subscription Agreement was amended and restated, among other things, for employee warrants to be issued to certain Pre-Merger Oruka’s employees, directors, and service providers, immediately prior to the closing of the Merger. Pursuant to this amendment, during the three months ended September 30, 2024, the Company issued 3,054,358 employee warrants at an exercise price of $7.80 per warrant, which are accounted as equity in the condensed consolidated financial statements The following table summarizes the employee warrant activity for the period from February 6, 2024 (inception) through September 30, 2024: Number of Weighted Weighted Aggregate Balance as of February 6, 2024 (inception) — $ — — $ — Granted 3,054,358 $ 7.80 Exercised — $ — Forfeited — $ — Balance as of September 30, 2024 3,054,358 $ 7.80 9.8 $ 51,038 Vested and expected to vest, September 30, 2024 3,054,358 $ 7.80 9.8 $ 51,038 Vested and exercisable, September 30, 2024 — $ — — $ — The weighted average grant-date fair value per share of employee warrants granted during the period from February 6, 2024 (inception) to September 30, 2024 was $6.27 per share. Aggregate intrinsic value represents the difference between the estimated fair value of the underlying Company Common Stock and the exercise price of outstanding, in-the-money employee warrants. The following table summarizes the weighted-average assumptions used in calculating the fair value of the employee warrants for the three months ended September 30, 2024 and for the period from February 6, 2024 (inception) to September 30, 2024: Three Months Ended Period from Expected term (in years) 6.1 6.1 Expected volatility 99.0 % 99.0 % Risk-free interest rate 4.2 % 4.2 % Expected dividend yield — % — % Stock-Based Compensation Expense The following table summarizes the classification of the Company’s stock-based compensation expense in the condensed consolidated statement of operations and comprehensive loss (in thousands): Three Months Ended Period from Research and development $ 7,772 $ 8,310 General and administrative 1,229 1,459 Total $ 9,001 $ 9,769 As of September 30, 2024, total unrecognized compensation cost related to the unvested stock options was $7.5 million, which is expected to be recognized over a weighted average period of approximately 3.4 years. As of September 30, 2024, total unrecognized compensation cost related to the unvested RSAs was less than $0.1 million, which is expected to be recognized over a weighted average period of 3.4 years. As of September 30, 2024, the unrecognized compensation cost related to the employee warrants was $17.8 million, which is expected to be recognized over a weighted average period of 3.6 years. The following table summarizes the award types of the Company’s stock-based compensation expense in the condensed consolidated statement of operations and comprehensive loss (in thousands): Three Months Ended Period from Paruka warrant obligation $ 7,251 $ 7,681 Employee warrants 1,314 1,314 Stock options 427 765 Employee stock purchase plan 9 9 Total $ 9,001 $ 9,769

Income Taxes

Income Taxes	8 Months Ended
	Sep. 30, 2024
Income Taxes [Abstract]
Income Taxes	9. Income Taxes No provision for income taxes was recorded for the three months ended September 30, 2024 and for the period of February 6, 2024 (inception) through September 30, 2024. Deferred tax assets generated from the Company’s net operating losses have been fully reserved, as the Company believes it is not more likely than not that the benefit will be realized due to the Company’s cumulative losses generated to date.

Option Agreements

Option Agreements	8 Months Ended
	Sep. 30, 2024
Option Agreements [Abstract]
Option Agreements	10. Option Agreements In March 2024, the Company entered into Option Agreements with Paragon and Paruka. Under the terms of the Option Agreements, Paragon identifies, evaluates and develops antibodies directed against certain mutually agreed therapeutic targets of interest to the Company. The Option Agreements include two selected targets, IL-23 (“ORKA-001”) and IL-17 A/F (“ORKA-002”). Under the Option Agreements, the Company has the exclusive options to, on a research program-by-research program basis, be granted an exclusive, worldwide license to all of Paragon’s right, title and interest in and to the intellectual property resulting from the applicable research program to develop, manufacture and commercialize the antibodies and products directed to the selected targets (each, an “Option”), with the exception of pursuing ORKA-001 for the treatment of inflammatory bowel disease. If the Company exercises its options, it will be required to make non-refundable milestone payments to Paragon of up to $12.0 million under each respective agreement upon the achievement of certain clinical development milestones, up to $10.0 million under each respective agreement upon the achievement of certain regulatory milestones as well as tiered royalty payments in the low-to-mid single-digits beginning on the first commercial sale. From time to time, the Company can choose to add additional targets to the collaboration by mutual agreement with Paragon. The Company’s exclusive Option with respect to each research program for a particular target initiated by the parties (“Research Program”) is exercisable at its sole discretion at any time during the period beginning on the initiation of activities under the associated Research Program and ending a specified number of days following (i) with respect to any Research Program other than ORKA-001, the delivery of the data package from Paragon related to the results of the Research Plan activities, or (ii) with respect to ORKA-001, the completion of the IL-23 antibody selection process described in the agreement (the “Option Period”). There is no payment due upon exercise of an Option pursuant to the Option Agreements. Unless terminated earlier, the Option Agreements shall continue in force on a Research Program-by-Research Program basis until the earlier of: (i) the end of the Option Period for such Research Program, as applicable, if such Option is not exercised by the Company; (ii) the expiration of the 30-day period after the Company exercises its Option with respect to such Research Program, subject to mutually agreed extension, during the Option Period and the parties are unable to finalize and execute a license agreement, and (iii) the expiration of the applicable research term (the “Term”). Upon the expiration of the Term for all then-existing Research Programs, under the Option Agreements, the Option Agreements will automatically expire in its entirety. The Company may terminate the Option Agreements or any Research Program at any time for any or no reason upon 30 days’ prior written notice to Paragon, provided that the Company must pay certain unpaid fees due to Paragon upon such termination, as well as any non-cancellable obligations reasonably incurred by Paragon in connection with its activities under any terminated Research Program. Paragon may terminate the Option Agreements or a Research Program immediately upon written notice to the Company if, as a result of any action or failure to act by the Company or its affiliates, such Research Program or all material activities under the applicable Research Plan are suspended, discontinued or otherwise delayed for a certain consecutive number of months. Each party has the right to terminate the Option Agreements or any Research Program upon (i) 30 days’ prior written notice of the other party’s material breach that remains uncured for the 30-day period and (ii) the other party’s bankruptcy. Pursuant to the Option Agreements, on a research program-by-research program basis following the finalization of the research plan for each respective research program, the Company was required to pay Paragon a one-time, nonrefundable research initiation fee of $0.8 million related to the ORKA-001 program. This amount was recognized as a research and development expense during the period from February 6, 2024 (inception) to September 30, 2024. In June 2024, pursuant to the Option Agreements with Paragon, the Company completed the selection process of its development candidate for IL-23 antibody for ORKA-001 program. The Company was responsible for 50% of the development costs incurred through the completion of the IL-23 selection process. The Company received the rights to at least one selected IL-23 antibody in June 2024. During the three months ended September 30, 2024, the Company exercised its option for ORKA-001 and recorded a $1.5 million milestone payment related to the achievement of development candidate as research and development expense in the Company’s condensed consolidated statements of operations and comprehensive loss for each of the three months ended September 30, 2024 and for the period from February 6, 2024 (inception) to September 30, 2024. The Company’s share of development costs incurred during the three months ended September 30, 3024 and for the period from February 6, 2024 (inception) to September 30, 2024 was $0.8 million and $13.2 million, respectively, which were recorded as research and development expenses during the respective periods. An amount of $2.3 million is included in related party accounts payable and other current liabilities as of September 30, 2024. The Company was also required to reimburse Paragon $3.3 million for development costs related to ORKA-002 incurred by Paragon through December 31, 2023 and certain other development costs incurred by Paragon between January 1, 2024 and March 6, 2024 as stipulated by the Option Agreements. This amount was recognized as a research and development expense during the period from February 6, 2024 (inception) to September 30, 2024. The Company is also responsible for the development costs incurred by Paragon from January 1, 2024 through the completion of the IL-17 selection process. The Company recognized an amount of $0.8 million payable to Paragon for the research initiation fee related to ORKA-002 following the finalization of the ORKA-002 research plan. This was recognized as research and development expenses in the period from February 6, 2024 (inception) to September 30, 2024. The Company accounted for development costs of $3.8 million and $6.6 million during the three months ended September 30, 3024 and for the period from February 6, 2024 (inception) to September 30, 2024, respectively, as research and development expenses during the respective periods. An amount of $3.8 million is included in related party accounts payable and other current liabilities as of September 30, 2024. As part of the Option Agreements, on each of December 31, 2024 and December 31, 2025, the Company will grant warrants to purchase a number of shares equal to 1.00% of outstanding shares as of the date of the grant on a fully diluted basis with an exercise price equal to the fair market value of the underlying shares on the grant date. The warrants are liability-classified and after the initial recognition, the liability is adjusted to fair value at the end of each reporting period, with changes in fair value recorded in the consolidated statement of operations and comprehensive loss (see Note 8) as stock-based compensation expenses under research and development expenses. The Company expenses the service fees as the associated costs are incurred when the underlying services are rendered. Such amounts are classified within research and development expenses in the accompanying condensed consolidated statement of operations and comprehensive loss. The Company concluded that the rights obtained under the Option Agreements represent an asset acquisition whereby the underlying assets comprise in-process research and development assets with no alternative future use. The Option Agreements did not qualify as a business combination because substantially all of the fair value of the assets acquired was concentrated in the exclusive license options, which represent a group of similar identifiable assets. The research initiation fee represents a one-time cost on a research program-by-research program basis for accessing research services or resources with benefits that are expected to be consumed in the near term, therefore the amounts paid are expensed as part of research and development costs immediately. Amounts paid as reimbursements of ongoing development cost, monthly development cost fee and additional development expenses incurred by Paragon due to work completed for selected targets prior to the effective date of the Option Agreements that is associated with services being rendered under the related Research Programs are recognized as research and development expense when incurred. For the three months ended September 30, 2024 and the period from February 6, 2024 (inception) to September 30, 2024, the Company recognized $13.4 million and $33.8 million of expenses, respectively, in connection with services provided by Paragon and Paruka under the Option Agreements.

Commitment and Contingencies

Commitment and Contingencies	8 Months Ended
	Sep. 30, 2024
Commitment and Contingencies [Abstract]
Commitment and Contingencies	11. Commitment and Contingencies Leases In April 2024, the Company entered into an operating lease agreement for the Company’s headquarters in Menlo Park, California, which commenced on June 15, 2024 with an initial term of 39.5 months. The Company leases office space under this noncancelable operating lease agreement. Lease liabilities are based on the net present value of the remaining lease payments over the remaining lease term. In determining the present value of lease payments, the Company used its incremental borrowing rate when measuring operating lease liabilities as discount rates were not implicit or readily determinable. As of September 30, 2024, the Company had $0.9 million of operating lease right-of-use assets, operating lease liability, current of $0.1 million, and operating lease liability, noncurrent of $0.8 million on its condensed consolidated balance sheets. As of September 30, 2024, the operating lease arrangement had a remaining lease term of 36.0 months and a discount rate of 17.95%. For the three months ended September 30, 2024 and the period from February 6, 2024 (inception) to September 30, 2024, the Company recorded operating and variable lease expense of $0.1 and $0.2 million, respectively, in general and administrative expenses in its condensed consolidated statements of operations and comprehensive loss. The following table presents the Company’s supplemental cash flow information related to leases (in thousands): September 30, Cash paid for amounts included in the measurement of lease liabilities Operating cash flow from operating leases $ 74 The following table summarizes a maturity analysis of the Company’s operating lease liabilities showing the aggregate lease payments as of September 30, 2024 (in thousands): Amount Fiscal year ending December 31, 2024 (remainder) $ 63 2025 369 2026 494 2027 380 Total undiscounted lease payments 1,306 Less: imputed interest (318 ) Total discounted lease payments 988 Less: current portion of lease liability (146 ) Non-current portion of lease liability $ 842

Net Loss Per Share

Net Loss Per Share	8 Months Ended
	Sep. 30, 2024
Earnings Per Share [Abstract]
Net Loss Per Share	12. Net Loss per Share Basic and diluted net loss per share attributable to stockholders were calculated as follows (in thousands, except share and per share data): Three Months Ended Period from Loss Allocation Weighted Average Shares Outstanding Loss Per Share – Basic and Diluted Loss Allocation Weighted Average Shares Outstanding Loss Per Share – Basic and Diluted Common Stock $ (21,936 ) 15,013,655 $ (1.46 ) $ (47,192 ) 7,765,381 $ (6.08 ) Company Series A Preferred Stock (1) (697 ) 477 $ (1,460.62 ) (1,121 ) 184 $ (6,077.13 ) Company Series B Preferred Stock (2) (5,990 ) 49,191 $ (121.77 ) (9,630 ) 19,015 $ (506.44 ) Net loss $ (28,623 ) $ (57,943 ) (1) The weighted-average number of shares of as-converted Company Series A Preferred Stock used in the loss allocation was 477,196 and 184,462 for the three months ended September 30, 2024 and for the period from February 6, 2024 (inception) to September 30, 2024, respectively. (2) The weighted-average number of shares of as-converted Company Series B Preferred Stock used in the loss allocation was 4,099,227 and 1,584,575 for the three months ended September 30, 2024 and for the period from February 6, 2024 (inception) to September 30, 2024, respectively. For the computation of basic net loss per share attributable to stockholders, the amount of weighted-average shares outstanding excludes all shares of unvested restricted common stock as such shares are not considered outstanding for accounting purposes until vested. The amount of weighted-average shares outstanding includes the pre-funded warrants as the exercise price is negligible and these warrants are fully vested and exercisable. The potential shares of common stock that were excluded from the computation of diluted net loss per share attributable to stockholders for the periods presented because including them would have had an anti-dilutive effect were as follows: Three Months Ended Period from Outstanding employee warrants to purchase common stock 3,054,358 3,054,358 Outstanding unvested restricted stock awards 2,207,553 2,207,553 Outstanding and issued common stock options 1,287,760 1,287,760 Total 6,549,671 6,549,671

Related Party Transactions

Related Party Transactions	8 Months Ended
	Sep. 30, 2024
Related Party Transactions [Abstract]
Related Party Transactions	13. Related Party Transactions Paragon and Paruka each beneficially own less than 5% of the Company’s capital stock through their respective holdings of Company Common Stock. Fairmount beneficially owns more than 5% of the Company’s capital, currently has one representative appointed to the Board, and beneficially owns more than 5% of Paragon. Fairmount appointed Paragon’s board of directors and has the contractual right to approve the appointment of any executive officers of Paragon. The following is a summary of related party accounts payable and other current liabilities (in thousands): September 30, Paragon reimbursable Option Agreements’ fees $ 6,140 Paragon reimbursable other research expenses 146 Paragon reimbursable patent expenses 71 $ 6,357

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	2 Months Ended	3 Months Ended		8 Months Ended
	Mar. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Sep. 30, 2024
Pay vs Performance Disclosure
Net Income (Loss)	$ (7,077)	$ (28,623)	$ (22,243)	$ (57,943)

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Sep. 30, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Accounting Policies, by Policy

Accounting Policies, by Policy (Policies)	8 Months Ended
	Sep. 30, 2024
Summary of Significant Accounting Policies [Abstract]
Use of Estimates	Use of Estimates The preparation of the Company’s condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates, assumptions, and judgments that affect the reported amounts of assets and liabilities and the disclosure of contingent liabilities at the date of the condensed consolidated financial statements and the reported amounts of income and expenses during the reporting periods. Significant estimates and assumptions reflected within these condensed consolidated financial statements include but are not limited to research and development expenses and related prepaid or accrued costs and the valuation of stock-based compensation awards and related expenses. The Company bases its estimates on known trends and other market-specific or other relevant factors that it believes to be reasonable under the circumstances. On an ongoing basis, management evaluates its estimates, as there are changes in circumstances, facts, and experience. Actual results could differ materially from those estimates or assumptions.
Concentrations of Credit Risk and Other Risks and Uncertainties	Concentrations of Credit Risk and Other Risks and Uncertainties The Company’s cash and cash equivalents are maintained with financial institutions in the United States of America. Cash balances are held at financial institutions and account balances may exceed federally insured limits. To date, the Company has not experienced any losses on its cash and cash equivalents and periodically evaluates the creditworthiness of its financial institutions. The Company manages credit risk associated with its investment portfolio through its investment policy, which limits investments to high-quality issuers and limits the amount of its portfolio that can be invested in a single issuer. The Company is dependent on third-party organizations to research, develop, manufacture, and process its product candidates for its development programs, including its two most advanced programs, ORKA-001 and ORKA-002. The Company expects to continue to be dependent on a small number of manufacturers to supply it with its requirements for all products. The Company’s research and development programs could be adversely affected by a significant interruption in the supply of the necessary materials. A significant amount of the Company’s research and development activities are performed under its agreements with Paragon Therapeutics, Inc. (“Paragon”) (see Note 10).
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments with an original maturity of three months or less at the time of initial purchase to be cash equivalents. The cash equivalents were comprised of investments in money market funds.
Debt Issuance Costs	Debt Issuance Costs Debt issuance costs incurred in connection with the Convertible Note (see Note 6) are recorded as a reduction of the carrying value of the notes payable liability on the Company’s balance sheet and are amortized to interest expense over the term of the loan using the effective interest method.
Subscription Receivable	Subscription Receivable The Company accounts for any notes received in exchange for common stock as a subscription receivable, provided the note underlying the receivable is paid prior to the date the financial statement is available to be issued.
Fair Value Measurements	Fair Value Measurements Certain assets and liabilities are carried at fair value under U.S. GAAP. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable: ● Level 1 — Quoted prices in active markets that are identical assets or liabilities. ● Level 2 — Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data. ● Level 3 — Unobservable inputs that are supported by little or no market activity that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies, and similar techniques. The Company’s cash equivalents are carried at fair value, determined according to the fair value hierarchy described above (see Note 4). The carrying values of the Company’s prepaid expenses and other current assets, accounts payable and accrued expenses and other current liabilities approximate their fair values due to their relatively short maturity period.
Property and Equipment	Property and Equipment Property and equipment are stated at cost less accumulated depreciation. Depreciation expense is recognized using the straight-line method over the estimated useful life of each asset as follows: Estimated Useful Life Furniture and fixtures 3-5 years Computer and office equipment 3-5 years
Classification of Convertible Preferred Stock	Classification of Convertible Preferred Stock Prior to the reverse recapitalization, the Company had classified its Pre-Merger Oruka Series A Preferred Stock outside of stockholders’ equity (deficit) on the Company’s condensed consolidated balance sheet because the holders of such stock have certain liquidation rights in the event of a deemed liquidation event that, in certain situations, is not solely within the control of the Company and would require the redemption of the then-outstanding convertible preferred stock. Upon the closing of the Merger, the Company converted its Pre-Merger Oruka Series A Preferred Stock to Company Series B Preferred Stock and has classified the Company Series B Preferred Stock within stockholders’ equity (deficit) on its condensed consolidated balance sheet because the Company Series B Preferred Stock is not redeemable or puttable to the Company by the holder under any circumstances. In connection with the PIPE Financing (see Note 1) the Company issued Company Series A Preferred Stock, and has classified the Company Series A Preferred Stock outside of stockholders’ equity (deficit) on the Company’s condensed consolidated balance sheet because the holders of such stock have certain rights (see Note 7) that, in certain situations, is not solely within the control of the Company and would require the redemption of the then-outstanding convertible preferred stock.
Note Payable to Related Party	Note Payable to Related Party The Company accounted for the Convertible Note (as defined in Note 6) at amortized cost. The Company considered if optional conversion features are required to be bifurcated and separately accounted for as a derivative. Costs related to the issuance of the Convertible Note were recorded as a debt discount, amortized over the term of the Convertible Note (see Note 6) and were accounted as interest expense in other income (expenses) within the condensed consolidated statements of operations and comprehensive loss using the effective interest method. At the effective time of the Merger, shares of Pre-Merger Oruka Common Stock issued pursuant to the conversion of the Convertible Note (including accrued interest) automatically converted into shares of Company Common Stock (see Note 1).
Research and Development Contract Costs Accruals	Research and Development Contract Costs Accruals The Company records the costs associated with research studies and manufacturing development as incurred. These costs are a significant component of the Company’s research and development expenses, with a substantial portion of the Company’s ongoing research and development activities conducted by third-party service providers, including contract research organizations (“CROs”) and contract manufacturing organizations (“CMOs”), and the Company’s related-party Paragon (see Note 10). The Company accrues for expenses resulting from obligations under its two antibody discovery and option agreements (the “Option Agreements”) (see Note 10), by and among Paragon, Paruka Holding LLC (“Paruka”), an entity formed by Paragon as a vehicle to hold equity in the Company, and the Company as well as agreements with CROs, CMOs, and other outside service providers for which payment flows do not match the periods over which materials or services are provided to the Company. Accruals are recorded based on estimates of services received and efforts expended pursuant to agreements established with Paragon, CROs, CMOs, and other outside service providers. These estimates are typically based on contracted amounts applied to the proportion of work performed and determined through analysis with internal personnel and external service providers as to the progress or stage of completion of the services. The Company makes significant judgments and estimates in determining the accrual balance in each reporting period. If advance payments are made to Paragon, a CRO, CMO, or outside service provider, the payments will be recorded as a prepaid asset which will be expensed as the contracted services are performed. Changes in these estimates that result in material changes to the Company’s accruals could materially affect the Company’s results of operations. As of September 30, 2024, the Company has not experienced any material deviations between accrued and actual research and development expenses.
Leases	Leases At the lease commencement date, when control of the underlying asset is transferred from the lessor to the Company, the Company classifies a lease as either an operating or finance lease and recognizes a right-of-use (“ROU”) asset and a current and non-current lease liability, as applicable, in the balance sheet if the lease has a term greater than one year. Lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise its option. At the lease commencement date, operating lease liabilities and their corresponding ROU assets are recorded at the present value of future minimum lease payments over the expected remaining lease term. The Company determines the present value of lease payments using the implicit rate, if it is readily determinable, or the risk-free discount rate for a period comparable with that of the lease term. For operating leases, lease expense for lease payments is recognized on a straight-line basis over the lease term. For finance leases, lease expense includes amortization expense of the ROU asset recognized on a straight-line basis over the lease term and interest expense recognized on the finance lease liability. In addition, certain adjustments to the ROU asset may be required for items such as lease prepayments, incentives received or initial direct costs. As of September 30, 2024, the Company has one operating lease and no finance leases. The Company accounts for lease and non-lease components related to operating leases as a single lease component. The Company has elected that costs associated with leases having an initial term of 12 months or less are recognized in the condensed consolidated statement of operations and comprehensive loss on a straight-line basis over the lease term and are not recorded on its condensed consolidated balance sheets. Variable lease expense is recognized as incurred and consists primarily of real estate taxes, utilities, and other office space related expenses.
Segment Reporting	Segment Reporting The Company operates and manages its business as a single segment for the purposes of assessing performance and making operating decisions. The Company’s chief executive officer, who is the chief operating decision maker (the “CODM”), reviews the Company’s financial information on an aggregated basis for purposes of evaluating financial performance and allocating resources.
Research and Development Costs	Research and Development Costs Research and development costs are expensed as incurred. Research and development costs include salaries and bonuses, stock-based compensation, employee benefits, and external costs of vendors and consultants engaged to conduct research and development activities, as well as allocated human resource costs, information technology costs, and facility-related costs, including rent, maintenance, utilities, and depreciation. Nonrefundable advance payments for goods or services to be received in the future for use in research and development activities are recorded as prepaid expenses on the accompanying condensed consolidated balance sheet. The prepaid amounts are expensed as the related goods are delivered or the services are performed, or when it is no longer expected that the goods will be delivered, or the services rendered. If nonrefundable advance payments represent a one-time cost for obtaining goods or services, with anticipated benefits to be utilized within a year of period end, the payment is expensed immediately.
General and Administrative Expenses	General and Administrative Expenses General and administrative expenses consist primarily of salaries and bonuses, stock-based compensation, employee benefits, finance and administration costs, patent and intellectual property costs, professional fees, as well as allocated human resource costs, information technology costs, and facility-related costs, including rent, maintenance, utilities and depreciation.
Commitments and Contingencies	Commitments and Contingencies The Company is subject to contingent liabilities, such as legal proceedings and claims, that arise in the ordinary course of business activities. The Company accrues for loss contingencies when losses become probable and are reasonably estimable. If the reasonable estimate of the loss is a range and no amount within the range is a better estimate, the minimum amount of the range is recorded as a liability on the balance sheet. The Company does not accrue for contingent losses that, in its judgment, are considered to be reasonably possible, but not probable; however, it discloses the range of reasonably possible losses. As of September 30, 2024, no liabilities were recorded for loss contingencies (see Note 11).
Stock-Based Compensation	Stock-Based Compensation The Company measures all stock-based awards granted to employees, directors, and non-employees in the form of stock options to purchase shares of its common stock, based on the fair value of the awards on the date of grant using the Black-Scholes option-pricing model. The Company measures restricted common stock awards (“RSAs”) using the difference, if any, between the purchase price per share of the award and the fair value of the Company’s common stock at the date of grant. The Company grants stock options, restricted stock awards, and warrants that are subject to service or performance-based vesting conditions. Compensation expense for awards to employees and directors with service-based vesting conditions is recognized using the straight-line method over the requisite service period, which is generally the vesting period of the respective award. Compensation expense for awards to non-employees with service-based vesting conditions is recognized in the same manner as if the Company had paid cash in exchange for the goods or services, which is generally over the vesting period of the award. Forfeitures are accounted for as they occur. As of each reporting date, the Company estimates the probability that specified performance criteria will be met and does not recognize compensation expense until it is probable that the performance-based vesting condition will be achieved. The Company has issued stock options, warrants, and RSAs with service-based and performance-based vesting conditions. The Company recognizes the compensation expense for the option to purchase common stock under the Employee Stock Purchase Plan (“ESPP”), based on the fair value of the common stock estimated using the closing price of the Company’s common stock as reported on the date of offering, less the purchase discount percentage provided for in the plan. The Company classifies stock-based compensation expense in its condensed consolidated statement of operations and comprehensive loss in the same manner in which the award recipient’s payroll costs are classified or in which the award recipient’s service payments are classified.
Net Loss per Share Attributable to Common Stockholders	Net Loss per Share Attributable to Stockholders Basic and diluted net loss attributable to stockholders per share is presented in conformity with the two-class method required for participating securities (Pre-Merger Oruka Series A Preferred Stock). Basic earnings per share is computed by dividing net income available to each class of shares by the weighted-average number of shares of common stock and participating securities outstanding during the period. Pre-funded warrants were included as the exercise price is negligible and these warrants are fully vested and exercisable. Company Series A Preferred Stock and Company Series B Preferred Stock share the same characteristics as Common Stock and have no substantive preference attributed to them and, accordingly, have been considered as classes of Common Stock in the computation of net loss per share regardless of their legal form. Net loss is allocated to common stock based on its proportional ownership on an as-converted basis. Net loss is not allocated to participating securities as they do not have an obligation to fund losses. The weighted-average number of shares outstanding of common stock reflects changes in ownership over the periods presented. See Note 7— Convertible Preferred Stock and Stockholders’ Equity. Diluted net loss per share is computed by dividing the net loss attributable to stockholders adjusted for income (expenses), net of tax, related to any diluted securities, by the weighted-average number of shares of common stock and potentially dilutive securities outstanding for the period. For purposes of this calculation, stock options to purchase common stock, employee warrants to purchase common stock, and unvested RSAs are considered potential dilutive common shares. The Company generated a net loss for the periods presented. Accordingly, basic and diluted net loss per share is the same because the inclusion of the potentially dilutive securities would be anti-dilutive.
Income Taxes	Income Taxes The Company accounts for income taxes using the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the financial statements or in the Company’s tax returns. Deferred tax assets and liabilities are determined based on the differences between the financial statement basis and tax basis of assets and liabilities using enacted tax rates in effect for the years in which the differences are expected to reverse. Changes in deferred tax assets and liabilities are recorded in the provision for income taxes. The Company assesses the likelihood that its deferred tax assets will be recovered from future taxable income and, to the extent it believes, based upon the weight of available evidence, that it is more likely than not that all or a portion of the deferred tax assets will not be realized, a valuation allowance is established through a charge to income tax expense. The potential for recovery of deferred tax assets is evaluated by estimating the future taxable profits expected and considering prudent and feasible tax planning strategies. The Company accounts for uncertainty in income taxes recognized in the condensed consolidated financial statements by applying a two-step process to determine the amount of tax benefit to be recognized. First, the tax position must be evaluated to determine the likelihood that it will be sustained upon external examination by the taxing authorities. If the tax position is deemed more likely than not to be sustained, the tax position is then assessed to determine the amount of benefit to recognize in the condensed consolidated financial statements. The amount of the benefit that may be recognized is the largest amount that has a greater than 50% likelihood of being realized upon ultimate settlement. The provision for income taxes includes the effects of any resulting tax reserves, or unrecognized tax benefits, that are considered appropriate as well as the related net interest and penalties. The Company had accrued no amounts for interest or penalties related to uncertain tax positions as of September 30, 2024.
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements In November 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2023-07, Segment Reporting Topic 280 : Improvements to Reportable Segment Disclosures In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures In November 2024, the FASB issued ASU 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Tables)	8 Months Ended
	Sep. 30, 2024
Summary of Significant Accounting Policies [Abstract]
Schedule of Property and Equipment	Property and equipment are stated at cost less accumulated depreciation. Depreciation expense is recognized using the straight-line method over the estimated useful life of each asset as follows: Estimated Useful Life Furniture and fixtures 3-5 years Computer and office equipment 3-5 years

Reverse Recapitalization and _2

Reverse Recapitalization and Pre-Closing Financing (Tables)	8 Months Ended
	Sep. 30, 2024
Reverse Recapitalization and Pre-Closing Financing [Abstract]
Schedule of the Assets and Liabilities	As part of the recapitalization, the Company acquired the assets and liabilities listed below (in thousands): Amount Cash and cash equivalents $ 4,940 Other current assets 114 Accrued liabilities (54 ) Net assets acquired $ 5,000

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	8 Months Ended
	Sep. 30, 2024
Fair Value Measurements [Abstract]
Schedule of Fair Value Hierarchy for Financial Assets Measured	The following tables present the Company’s fair value hierarchy for financial assets measured as of September 30, 2024 (in thousands): Fair Value Measurements as of September 30, 2024 Level 1 Level 2 Level 3 Total Financial assets: Money market funds $ 403,322 $ — $ — $ 403,322 Total financial assets $ 403,322 $ — $ — $ 403,322

Accrued Expenses and Other Cu_2

Accrued Expenses and Other Current Liabilities (Tables)	8 Months Ended
	Sep. 30, 2024
Accrued Expenses and Other Current Liabilities [Abstract]
Schedule of Accrued Expenses and Other Current Liabilities	Accrued expenses and other current liabilities consisted of the following (in thousands): September 30, Accrued employee compensation and benefits $ 933 Accrued professional and consulting 204 Accrued research and development 573 $ 1,710

Convertible Preferred Stock a_2

Convertible Preferred Stock and Stockholders’ Equity (Tables)	8 Months Ended
	Sep. 30, 2024
Convertible Preferred Stock and Stockholders’ Equity [Abstract]
Schedule of Convertible Preferred Stock	As of September 30, 2024, convertible preferred stock consisted of the following (in thousands, except share data): September 30, 2024 Preferred Stock Preferred Stock Carrying Common Stock Series A Non-Voting Preferred Stock 2,439 2,439 $ 52,841 2,439,000 Series B Non-Voting Preferred Stock 251,504 137,138 $ 2,931 11,428,149
Schedule of Common Stock Reserved for Future Issuance	As of September 30, 2024, the Company had common stock reserved for future issuance as follows: September 30, Shares issuable on conversion of Company Series A Preferred Stock 2,439,000 Shares issuable on conversion of Company Series B Preferred Stock 11,428,149 Shares issuable upon exercise of pre-funded warrants 6,202,207 Outstanding and issued stock options 1,287,760 Outstanding and issued employee warrants 3,054,358 Shares available for grant under 2024 Stock Incentive Plan 4,526,324 Shares available for grant under 2024 Employee Stock Purchase Plan 463,489 Total shares of common stock reserved 29,401,287

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	8 Months Ended
	Sep. 30, 2024
Stock-Based Compensation [Abstract]
Schedule of Weighted-Average Assumptions or Range of Assumptions used in Calculating the Fair Value of the Employee Warrants	The following table summarizes the weighted-average assumptions used in calculating the fair value of the awards for the three months ended September 30, 2024 and for the period from February 6, 2024 (inception) to September 30, 2024: Three Period from Expected term (in years) 6.1 6.1 Expected volatility 97.3 % 101.0 % Risk-free interest rate 3.5 % 4.3 % Expected dividend yield — % — %
Schedule of Stock Option Activity	The following table summarizes the stock option activities under the 2024 Plan and 2024 Stock Plan for the period of February 6, 2024 (inception) through September 30, 2024: Number of Weighted Weighted Aggregate Balance as of February 6, 2024 (inception) — $ — — $ — Granted 1,287,760 $ 7.97 Exercised — $ — Forfeited — $ — Balance as of September 30, 2024 1,287,760 $ 7.97 9.6 $ 21,507 Vested and expected to vest, September 30, 2024 1,287,760 $ 7.97 9.6 $ 21,507 Exercisable, September 30, 2024 — $ — — $ —
Schedule of RSAs activity	The following table summarizes the RSAs activity for the period from February 6, 2024 (inception) through September 30, 2024: Number of Weighted Unvested balance as of February 6, 2024 (inception) — $ — Granted 2,207,553 — Unvested balance as of September 30, 2024 2,207,553 $ —
Schedule of Employee Warrant Activity	The following table summarizes the employee warrant activity for the period from February 6, 2024 (inception) through September 30, 2024: Number of Weighted Weighted Aggregate Balance as of February 6, 2024 (inception) — $ — — $ — Granted 3,054,358 $ 7.80 Exercised — $ — Forfeited — $ — Balance as of September 30, 2024 3,054,358 $ 7.80 9.8 $ 51,038 Vested and expected to vest, September 30, 2024 3,054,358 $ 7.80 9.8 $ 51,038 Vested and exercisable, September 30, 2024 — $ — — $ —
Schedule of Weighted-Average Assumptions Used in Calculating the Fair Value of the Employee Warrants	The following table summarizes the weighted-average assumptions used in calculating the fair value of the employee warrants for the three months ended September 30, 2024 and for the period from February 6, 2024 (inception) to September 30, 2024: Three Months Ended Period from Expected term (in years) 6.1 6.1 Expected volatility 99.0 % 99.0 % Risk-free interest rate 4.2 % 4.2 % Expected dividend yield — % — %
Schedule of Company’s Stock-Based Compensation Expense	The following table summarizes the classification of the Company’s stock-based compensation expense in the condensed consolidated statement of operations and comprehensive loss (in thousands): Three Months Ended Period from Research and development $ 7,772 $ 8,310 General and administrative 1,229 1,459 Total $ 9,001 $ 9,769
Schedule of Award Types of Company’s Stock-Based Compensation Expense	The following table summarizes the award types of the Company’s stock-based compensation expense in the condensed consolidated statement of operations and comprehensive loss (in thousands): Three Months Ended Period from Paruka warrant obligation $ 7,251 $ 7,681 Employee warrants 1,314 1,314 Stock options 427 765 Employee stock purchase plan 9 9 Total $ 9,001 $ 9,769

Commitment and Contingencies (T

Commitment and Contingencies (Tables)	8 Months Ended
	Sep. 30, 2024
Commitment and Contingencies [Abstract]
Schedule of Company’s Supplemental Cash Flow Information Related to Leases	The following table presents the Company’s supplemental cash flow information related to leases (in thousands): September 30, Cash paid for amounts included in the measurement of lease liabilities Operating cash flow from operating leases $ 74
Schedule of Company’s Operating Lease Liabilities Showing the Aggregate Lease Payments	The following table summarizes a maturity analysis of the Company’s operating lease liabilities showing the aggregate lease payments as of September 30, 2024 (in thousands): Amount Fiscal year ending December 31, 2024 (remainder) $ 63 2025 369 2026 494 2027 380 Total undiscounted lease payments 1,306 Less: imputed interest (318 ) Total discounted lease payments 988 Less: current portion of lease liability (146 ) Non-current portion of lease liability $ 842

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	8 Months Ended
	Sep. 30, 2024
Earnings Per Share [Abstract]
Schedule of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders	Basic and diluted net loss per share attributable to stockholders were calculated as follows (in thousands, except share and per share data): Three Months Ended Period from Loss Allocation Weighted Average Shares Outstanding Loss Per Share – Basic and Diluted Loss Allocation Weighted Average Shares Outstanding Loss Per Share – Basic and Diluted Common Stock $ (21,936 ) 15,013,655 $ (1.46 ) $ (47,192 ) 7,765,381 $ (6.08 ) Company Series A Preferred Stock (1) (697 ) 477 $ (1,460.62 ) (1,121 ) 184 $ (6,077.13 ) Company Series B Preferred Stock (2) (5,990 ) 49,191 $ (121.77 ) (9,630 ) 19,015 $ (506.44 ) Net loss $ (28,623 ) $ (57,943 ) (1) The weighted-average number of shares of as-converted Company Series A Preferred Stock used in the loss allocation was 477,196 and 184,462 for the three months ended September 30, 2024 and for the period from February 6, 2024 (inception) to September 30, 2024, respectively. (2) The weighted-average number of shares of as-converted Company Series B Preferred Stock used in the loss allocation was 4,099,227 and 1,584,575 for the three months ended September 30, 2024 and for the period from February 6, 2024 (inception) to September 30, 2024, respectively.
Schedule of Anti-Dilutive Effect Excluded from Potential Computation of Diluted Net Loss Per Share	The potential shares of common stock that were excluded from the computation of diluted net loss per share attributable to stockholders for the periods presented because including them would have had an anti-dilutive effect were as follows: Three Months Ended Period from Outstanding employee warrants to purchase common stock 3,054,358 3,054,358 Outstanding unvested restricted stock awards 2,207,553 2,207,553 Outstanding and issued common stock options 1,287,760 1,287,760 Total 6,549,671 6,549,671

Related Party Transactions (Tab

Related Party Transactions (Tables)	8 Months Ended
	Sep. 30, 2024
Related Party Transactions [Abstract]
Schedule of Related Party Accounts Payable and Other Current Liabilities	The following is a summary of related party accounts payable and other current liabilities (in thousands): September 30, Paragon reimbursable Option Agreements’ fees $ 6,140 Paragon reimbursable other research expenses 146 Paragon reimbursable patent expenses 71 $ 6,357

Nature of the Business and Ba_2

Nature of the Business and Basis of Presentation (Details)			2 Months Ended	3 Months Ended		5 Months Ended	8 Months Ended
	Apr. 03, 2024 USD ($)	Mar. 31, 2024 $ / shares shares	Mar. 31, 2024 USD ($) $ / shares	Sep. 30, 2024 USD ($) $ / shares shares	Jun. 30, 2024 USD ($) $ / shares shares	Jun. 30, 2024 USD ($) $ / shares shares	Sep. 30, 2024 USD ($) $ / shares shares	Aug. 29, 2024 $ / shares	Feb. 06, 2024 USD ($) $ / shares
Nature of the Business and Basis of Presentation [Line Items]
Common stock, par value (in Dollars per share) | $ / shares				$ 0.001			$ 0.001		$ 0.001
Additional paid-in capital transaction costs | $	$ 20,500,000
Net loss per share (in Dollars per share) | $ / shares				$ (1.46)			$ (6.08)
Common stock issued | $				$ 35,000			$ 35,000
Common Stock exchange (in Shares)					39,873,706	39,873,706
Common stock conversion of convertible note (in Shares)							2,722,207
Pre-funded warrants of common stock shares (in Shares)							5,522,207
Warrants exchange (in Shares)				9,664,208			9,664,208
Convertible shares (in Shares)							2,722,207
Net loss | $			$ (7,077,000)	$ (28,623,000)	$ (22,243,000)		$ (57,943,000)
Net cash | $				39,000,000			39,000,000
Cash and cash equivalents | $				$ 410,875,000			410,875,000
Pre-funded Warrants [Member]
Nature of the Business and Basis of Presentation [Line Items]
Aggregate net proceeds | $							$ 188,700,000
Price per share (in Dollars per share) | $ / shares				$ 22.999			$ 22.999
Net of issuance costs | $							$ 11,800,000
Reverse Stock Split [Member]
Nature of the Business and Basis of Presentation [Line Items]
Net loss per share (in Dollars per share) | $ / shares			$ (2.21)		$ (6.96)	$ (9.17)
Common Stock [Member]
Nature of the Business and Basis of Presentation [Line Items]
Common stock issued | $					$ 22,784,139	$ 22,784,139
Common Stock exchange (in Shares)				4,764,032			4,764,032
Number of shares issued to purchase (in Shares)							680,000
Series A Non-Voting Convertible Preferred Stock [Member]
Nature of the Business and Basis of Presentation [Line Items]
Purchase price | $							$ 23,000
Number of shares issued to purchase (in Shares)							2,439
Series A Preferred Stock [Member]
Nature of the Business and Basis of Presentation [Line Items]
Price per share (in Dollars per share) | $ / shares		$ 0.15	$ 0.15
Convertible shares (in Shares)							1,000
Number of shares issued to purchase (in Shares)		20,000,000
Oruka common stock [Member]
Nature of the Business and Basis of Presentation [Line Items]
Common stock, par value (in Dollars per share) | $ / shares				$ 0.001			$ 0.001	$ 0.001
Aggregate net proceeds | $	275,000,000
Oruka pre-funded warrants [Member]
Nature of the Business and Basis of Presentation [Line Items]
Purchased shares of common stock | $	$ 25,000,000
ARCA common stock [Member]
Nature of the Business and Basis of Presentation [Line Items]
Exchange ratio							6.8569
Oruka restricted stock [Member]
Nature of the Business and Basis of Presentation [Line Items]
Common stock, par value (in Dollars per share) | $ / shares				0.0001			$ 0.0001
Private Placement [Member]
Nature of the Business and Basis of Presentation [Line Items]
Price per share (in Dollars per share) | $ / shares				22.999			$ 22.999
Number of shares issued to purchase (in Shares)							680,000
Private Placement [Member] | Common Stock [Member]
Nature of the Business and Basis of Presentation [Line Items]
Common stock, par value (in Dollars per share) | $ / shares				$ 0.001			$ 0.001
Number of shares purchased (in Shares)				5,600,000			5,600,000
Price per share (in Dollars per share) | $ / shares				$ 23			$ 23
Private Placement [Member] | Series A Non-Voting Convertible Preferred Stock [Member]
Nature of the Business and Basis of Presentation [Line Items]
Preferred Stock, Convertible, Shares Issuable (in Shares)				2,439			2,439

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Details)	8 Months Ended
	Sep. 30, 2024	Jun. 15, 2024
Summary of Significant Accounting Policies [Abstract]
Lease terms	1 year	39 months 15 days
Income tax percentage	50%

Summary of Significant Accoun_4

Summary of Significant Accounting Policies (Details) - Schedule of Property and Equipment	Sep. 30, 2024
Minimum [Member] | Furniture and fixtures [Member]
Schedule of Property and Equipment [Line Items]
Estimated useful life	3 years
Minimum [Member] | Computer and office equipment [Member]
Schedule of Property and Equipment [Line Items]
Estimated useful life	3 years
Maximum [Member] | Furniture and fixtures [Member]
Schedule of Property and Equipment [Line Items]
Estimated useful life	5 years
Maximum [Member] | Computer and office equipment [Member]
Schedule of Property and Equipment [Line Items]
Estimated useful life	5 years

Reverse Recapitalization and _3

Reverse Recapitalization and Pre-Closing Financing (Details) - Schedule of the Assets and Liabilities $ in Thousands	Sep. 30, 2024 USD ($)
Schedule of the Assets and Liabilities [Abstract]
Cash and cash equivalents	$ 4,940
Other current assets	114
Accrued liabilities	(54)
Net assets acquired	$ 5,000

Fair Value Measurements (Detail

Fair Value Measurements (Details) - Schedule of Fair Value Hierarchy for Financial Assets Measured $ in Thousands	Sep. 30, 2024 USD ($)
Financial assets:
Financial assets	$ 403,322
Level 1 [Member]
Financial assets:
Financial assets	403,322
Level 2 [Member]
Financial assets:
Financial assets
Level 3 [Member]
Financial assets:
Financial assets
Money market funds [Member]
Financial assets:
Financial assets	403,322
Money market funds [Member] | Level 1 [Member]
Financial assets:
Financial assets	403,322
Money market funds [Member] | Level 2 [Member]
Financial assets:
Financial assets
Money market funds [Member] | Level 3 [Member]
Financial assets:
Financial assets

Accrued Expenses and Other Cu_3

Accrued Expenses and Other Current Liabilities (Details) - Schedule of Accrued Expenses and Other Current Liabilities - USD ($) $ in Thousands	Sep. 30, 2024	Feb. 06, 2024
Schedule of Accrued Expenses and Other Current Liabilities [Abstract]
Accrued employee compensation and benefits	$ 933
Accrued professional and consulting	204
Accrued research and development	573
Total	$ 1,710

Note Payable with Related Par_2

Note Payable with Related Party (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	8 Months Ended
	Mar. 31, 2024	Sep. 30, 2024	Sep. 30, 2024
Note Payable with Related Party [Line Items]
Maturity date	Dec. 31, 2025
Interest expense			$ 1.5
Aggregate principal amount			$ 25
Converted shares (in Shares)			2,722,207
Fairmount Healthcare Fund II, L.P. [Member]
Note Payable with Related Party [Line Items]
Initial principal amount	$ 25
Convertible Note [Member]
Note Payable with Related Party [Line Items]
Interest rate, percentage	12%
Debt issuance costs		$ 0.1
Interest expense		$ 0.5
Unpaid accrued interest			$ 1.5
Series A Preferred Stock [Member]
Note Payable with Related Party [Line Items]
Aggregate proceeds	$ 25
Converted shares (in Shares)			1,000

Convertible Preferred Stock a_3

Convertible Preferred Stock and Stockholders’ Equity (Details) $ / shares in Units, $ in Thousands			2 Months Ended	8 Months Ended
	Aug. 31, 2024 $ / shares shares	Mar. 31, 2024 USD ($) $ / shares shares	Mar. 31, 2024 $ / shares shares	Sep. 30, 2024 USD ($) $ / shares shares	Feb. 06, 2024 shares
Convertible Preferred Stock and Stockholders’ Equity [Line Items]
Exercisable shares	9.7
Expiration date
Warrants exercised
Gross proceeds (in Dollars) | $		$ 3,000		$ 2,931
Issuance costs (in Dollars) | $				$ 100
Common stock, shares authorized				545,000,000	65,000,000
Common stock, shares issued				34,998,550	3,197,975
Common stock, shares outstanding				34,998,550	3,197,975
Employee Warrants [Member]
Convertible Preferred Stock and Stockholders’ Equity [Line Items]
Warrants outstanding				3,054,358
Exercise price per warrant (in Dollars per share) | $ / shares				$ 7.8
Warrants exercised
Employee warrants issued				3,054,358
Employee warrants vest over a period				4 years
Minimum [Member]
Convertible Preferred Stock and Stockholders’ Equity [Line Items]
Common stock ratio				9.99
Maximum [Member]
Convertible Preferred Stock and Stockholders’ Equity [Line Items]
Common stock ratio				19.99
Series A Preferred Stock [Member]
Convertible Preferred Stock and Stockholders’ Equity [Line Items]
Number of Shares issued		20,000,000
Purchase price per share (in Dollars per share) | $ / shares		$ 0.15	$ 0.15
Series B Preferred Stock [Member]
Convertible Preferred Stock and Stockholders’ Equity [Line Items]
Converted shares	137,138
Series A Non-Voting Convertible Preferred Stock [Member]
Convertible Preferred Stock and Stockholders’ Equity [Line Items]
Number of Shares issued				2,439
Series B Non-Voting Preferred Stock [Member]
Convertible Preferred Stock and Stockholders’ Equity [Line Items]
Purchase price per share (in Dollars per share) | $ / shares				$ 23,000
Common Stock [Member]
Convertible Preferred Stock and Stockholders’ Equity [Line Items]
Pre-funded warrants			2,207,553
Exercise price per warrant (in Dollars per share) | $ / shares	$ 0.01
Common stock, shares authorized				545,000,000
Common stock, shares issued				34,988,550
Common stock, shares outstanding				2,207,553
Pre-Funded Warrants [Member]
Convertible Preferred Stock and Stockholders’ Equity [Line Items]
Pre-funded warrants	5,522,207
Warrants outstanding	5,522,207			6,202,207
Exercisable shares	5,522,207
Private Placement [Member]
Convertible Preferred Stock and Stockholders’ Equity [Line Items]
Exercisable shares				680,000
Number of Shares issued				680,000
Purchase price per share (in Dollars per share) | $ / shares				$ 22.999
Private Placement [Member] | Series A Non-Voting Convertible Preferred Stock [Member]
Convertible Preferred Stock and Stockholders’ Equity [Line Items]
Converted shares				2,439
Private Placement [Member] | Common Stock [Member]
Convertible Preferred Stock and Stockholders’ Equity [Line Items]
Exercise price per warrant (in Dollars per share) | $ / shares				$ 0.001

Convertible Preferred Stock a_4

Convertible Preferred Stock and Stockholders’ Equity (Details) - Schedule of Convertible Preferred Stock - USD ($) $ in Thousands	Sep. 30, 2024	Feb. 06, 2024
Series A Non-Voting Preferred Stock [Member]
Auction Market Preferred Securities, Stock Series [Line Items]
Preferred Stock Authorized	2,439
Preferred Stock Issued and Outstanding	2,439
Carrying Value (in Dollars)	$ 52,841
Common Stock Issuable Upon Conversion	2,439,000,000
Series B Non-Voting Preferred Stock [Member]
Auction Market Preferred Securities, Stock Series [Line Items]
Preferred Stock Authorized	251,504
Preferred Stock Issued and Outstanding	137,138
Carrying Value (in Dollars)	$ 2,931
Common Stock Issuable Upon Conversion	11,428,149,000

Convertible Preferred Stock a_5

Convertible Preferred Stock and Stockholders’ Equity (Details) - Schedule of Common Stock Reserved for Future Issuance - shares	Sep. 30, 2024	Feb. 05, 2024
Schedule of Common Stock Reserved for Future Issuance [Line Items]
Shares issuable upon exercise of pre-funded warrants	6,202,207
Outstanding and issued stock options	1,287,760
Outstanding and issued employee warrants	3,054,358
Shares issuable on conversion of Company Series A Preferred Stock [Member]
Schedule of Common Stock Reserved for Future Issuance [Line Items]
Shares issuable on conversion of Company preferred stock	2,439,000
Shares issuable on conversion of Company Series B Preferred Stock [Member]
Schedule of Common Stock Reserved for Future Issuance [Line Items]
Shares issuable on conversion of Company preferred stock	11,428,149
2024 Stock Incentive Plan [Member]
Schedule of Common Stock Reserved for Future Issuance [Line Items]
Shares available for grant	4,526,324
2024 Employee Stock Purchase Plan [Member]
Schedule of Common Stock Reserved for Future Issuance [Line Items]
Shares available for grant	463,489
Total shares of common stock reserved	29,401,287

Stock-Based Compensation (Detai

Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Millions		8 Months Ended
	Aug. 29, 2024	Sep. 30, 2024	Dec. 31, 2024	Aug. 31, 2024	Feb. 06, 2024
Stock-Based Compensation [Line Items]
Common stock shares (in Shares)		34,998,550			3,197,975
Percentage of diluted stock		1%
Shares issued (in Shares)		3,054,358
Price per share (in Dollars per share)		$ 0.0001
Share outstanding percentage		1%
Employee Warrants [Member]
Stock-Based Compensation [Line Items]
Employee warrants issued (in Shares)		3,054,358
Exercise price (in Dollars per share)		$ 7.8
Warrant [Member]
Stock-Based Compensation [Line Items]
Weighted average grant-date fair value (in Dollars per share)		$ 6.27
Total unrecognized compensation cost		$ 17.8
Weighted average period		3 years 7 months 6 days
Stock Options [Member]
Stock-Based Compensation [Line Items]
Weighted average grant-date fair value (in Dollars per share)		$ 6.44
Common Stock [Member]
Stock-Based Compensation [Line Items]
Common stock shares (in Shares)		34,988,550
Exercise price (in Dollars per share)				$ 0.01
2024 Stock Incentive Plan [Member] | Common Stock [Member]
Stock-Based Compensation [Line Items]
Common stock shares (in Shares)		4,634,891
2024 Employee Stock Purchase Plan [Member]
Stock-Based Compensation [Line Items]
Shares were reserved for issuance (in Shares)	463,489
Paruka Warrant Obligation [Member] | Minimum [Member]
Stock-Based Compensation [Line Items]
Total unrecognized compensation cost		$ 7.3
Paruka Warrant Obligation [Member] | Maximum [Member]
Stock-Based Compensation [Line Items]
Total unrecognized compensation cost		$ 7.7
2024 Stock Incentive Plan [Member]
Stock-Based Compensation [Line Items]
Percentage of diluted stock		5%
2024 Stock Incentive Plan [Member] | Common Stock [Member]
Stock-Based Compensation [Line Items]
Common stock shares (in Shares)		4,526,324
Restricted Stock Awards [Member]
Stock-Based Compensation [Line Items]
Shares issued (in Shares)		2,207,553
Total unrecognized compensation cost		$ 0.1
Weighted average period		3 years 4 months 24 days
Unvested Stock Options [Member]
Stock-Based Compensation [Line Items]
Total unrecognized compensation cost		$ 7.5
Weighted average period		3 years 4 months 24 days
Subsequent Event [Member]
Stock-Based Compensation [Line Items]
Estimated fair value of warrants to be granted			$ 11

Stock-Based Compensation (Det_2

Stock-Based Compensation (Details) - Schedule of Weighted-Average Assumptions or Range of Assumptions used in Calculating the Fair Value of the Employee Warrants - Stock Option Valuation [Member]	3 Months Ended	8 Months Ended
	Sep. 30, 2024	Sep. 30, 2024
Schedule of Weighted-Average Assumptions or Range of Assumptions used in Calculating the Fair Value of the Employee Warrants [Line Items]
Expected term (in years)	6 years 1 month 6 days	6 years 1 month 6 days
Expected volatility	97.30%	101%
Risk-free interest rate	3.50%	4.30%
Expected dividend yield

Stock-Based Compensation (Det_3

Stock-Based Compensation (Details) - Schedule of Stock Option Activity - USD ($) $ / shares in Units, $ in Thousands	8 Months Ended
	Sep. 30, 2024	Aug. 31, 2024
Schedule of Stock Option Activity [Abstract]
Number of Stock Options, Beginning Balance
Weighted Average Exercise Price Per Share, Beginning Balance
Weighted Average Remaining Contractual Term (in Years), Beginning Balance
Aggregate Intrinsic Value, Beginning Balance
Number of Stock Options, Ending Balance	1,287,760
Weighted Average Exercise Price Per Share, Ending Balance	$ 7.97
Weighted Average Remaining Contractual Term (in Years), Ending Balance	9 years 7 months 6 days
Aggregate Intrinsic Value, Ending Balance	$ 21,507
Number of Stock Options, Vested and expected to vest	1,287,760
Weighted Average Exercise Price Per Share, Vested and expected to vest, September 30, 2024	$ 7.97
Weighted Average Remaining Contractual Term (in Years), Vested and expected to vest, September 30, 2024	9 years 7 months 6 days
Aggregate Intrinsic Value, Vested and expected to vest	$ 21,507
Number of Stock Options, Exercisable		9.7
Weighted Average Exercise Price Per Share, Exercisable, September 30, 2024
Weighted Average Remaining Contractual Term (in Years), Exercisable, September 30, 2024
Aggregate Intrinsic Value, Exercisable, September 30, 2024
Number of Stock Options, Granted	1,287,760
Weighted Average Exercise Price Per Share, Granted	$ 7.97
Number of Stock Options, Exercised
Weighted Average Exercise Price Per Share, Exercised
Number of Stock Options, Forfeited
Weighted Average Exercise Price Per Share, Forfeited

Stock-Based Compensation (Det_4

Stock-Based Compensation (Details) - Schedule of RSAs activity - Restricted Stock Activity [Member]	8 Months Ended
	Sep. 30, 2024 $ / shares shares
Schedule of RSAs activity [Line Items]
Number of RSAs, Unvested balance | shares
Weighted Average Grant Date Fair Value, Unvested balance | $ / shares
Number of RSAs, Granted | shares	2,207,553
Weighted Average Grant Date Fair Value, Granted | $ / shares
Number of RSAs, Unvested balance | shares	2,207,553
Weighted Average Grant Date Fair Value, Unvested balance | $ / shares

Stock-Based Compensation (Det_5

Stock-Based Compensation (Details) - Schedule of Employee Warrant Activity $ / shares in Units, $ in Thousands	8 Months Ended
	Sep. 30, 2024 USD ($) $ / shares shares
Schedule of Summarizes the Employee Warrant Activity [Abstract]
Number of Warrants, Beginning balance | shares
Weighted Average Exercise Price Per Share, Beginning balance | $ / shares
Weighted Average Remaining Contractual Term, Beginning balance
Aggregate Intrinsic Value, Beginning balance | $
Number of Warrants, Endning balance | shares	3,054,358
Weighted Average Exercise Price Per Share, Endning balance | $ / shares	$ 7.8
Weighted Average Remaining Contractual Term, Endning balance	9 years 9 months 18 days
Aggregate Intrinsic Value, Endning balance | $	$ 51,038
Number of Warrants, Vested and expected to vest | shares	3,054,358
Weighted Average Exercise Price Per Share, Vested and expected to vest | $ / shares	$ 7.8
Weighted Average Remaining Contractual Term, Vested and expected to vest	9 years 9 months 18 days
Aggregate Intrinsic Value, Vested and expected to vest | $	$ 51,038
Number of Warrants, Vested and exercisable | shares
Weighted Average Exercise Price Per Share, Vested and exercisable | $ / shares
Weighted Average Remaining Contractual Term, Vested and exercisable
Aggregate Intrinsic Value, Vested and exercisable | $
Number of Warrants, Granted | shares	3,054,358
Weighted Average Exercise Price Per Share, Granted | $ / shares	$ 7.8
Number of Warrants, Exercised | shares
Weighted Average Exercise Price Per Share, Exercised | $ / shares
Number of Warrants, Forfeited | shares
Weighted Average Exercise Price Per Share, Forfeited | $ / shares

Stock-Based Compensation (Det_6

Stock-Based Compensation (Details) - Schedule of Weighted-Average Assumptions Used in Calculating the Fair Value of the Employee Warrants	3 Months Ended	8 Months Ended
	Sep. 30, 2024	Sep. 30, 2024
Schedule of Weighted-Average Assumptions Used in Calculating the Fair Value of the Employee Warrants [Abstract]
Expected term (in years)	6 years 1 month 6 days	6 years 1 month 6 days
Expected volatility	99%	99%
Risk-free interest rate	4.20%	4.20%
Expected dividend yield

Stock-Based Compensation (Det_7

Stock-Based Compensation (Details) - Schedule of Company’s Stock-Based Compensation Expense - USD ($) $ in Thousands	3 Months Ended	8 Months Ended
	Sep. 30, 2024	Sep. 30, 2024
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 9,001	$ 9,769
Research and Development Expense [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	7,772	8,310
General and Administrative Expense [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 1,229	$ 1,459

Stock-Based Compensation (Det_8

Stock-Based Compensation (Details) - Schedule of Award Types of Company’s Stock-Based Compensation Expense - USD ($) $ in Thousands	3 Months Ended	8 Months Ended
	Sep. 30, 2024	Sep. 30, 2024
Schedule of Award Types of Company’s Stock-Based Compensation Expense [Abstract]
Paruka warrant obligation	$ 7,251	$ 7,681
Employee warrants	1,314	1,314
Stock options	427	765
Employee stock purchase plan	9	9
Total	$ 9,001	$ 9,769

Income Taxes (Details)

Income Taxes (Details)	Sep. 30, 2024 USD ($)
Income Taxes [Abstract]
Provision for income taxes	$ 0

Option Agreements (Details)

Option Agreements (Details) - USD ($) $ in Millions				1 Months Ended	3 Months Ended	8 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Mar. 31, 2024	Sep. 30, 2024	Sep. 30, 2024
Paragon Option Agreements [Line Items]
Initiation fee						$ 0.8
Development costs, percentage						50%
Research and development expenses					$ 3.8	$ 6.6
Development costs			$ 3.3
Research initiation fee					0.8	0.8
Accounts payable and other current liabilities					3.8	3.8
Expenses					13.4	33.8
Clinical Development Milestones [Member]
Paragon Option Agreements [Line Items]
Non-refundable milestone payments				$ 12
Certain Regulatory Milestones [Member]
Paragon Option Agreements [Line Items]
Non-refundable milestone payments				$ 10
Related Party [Member]
Paragon Option Agreements [Line Items]
Accounts payable and other current liabilities					2.3	2.3
Research and Development Expense [Member] | ORKA-001 [Member]
Paragon Option Agreements [Line Items]
Milestone payment					1.5
Research and Development Expenses [Member]
Paragon Option Agreements [Line Items]
Research and development expenses					$ 0.8	$ 13.2
Forecast [Member]
Paragon Option Agreements [Line Items]
Percentage of warrant purchase	1%
Forecast [Member] | ORKA-002 [Member]
Paragon Option Agreements [Line Items]
Percentage of warrant purchase		1%

Commitment and Contingencies (D

Commitment and Contingencies (Details) - USD ($) $ in Thousands	3 Months Ended	8 Months Ended
	Sep. 30, 2024	Sep. 30, 2024	Jun. 15, 2024	Feb. 06, 2024
Commitment and Contingencies [Line Items]
Leases term	1 year	1 year	39 months 15 days
Operating lease right-of-use assets	$ 938	$ 938
Operating lease liability, current	146	146
Operating lease liability, noncurrent	$ 842	$ 842
Lease term	36 months	36 months
Lease discount rate	17.95%	17.95%
Variable lease expense	$ 100	$ 200
Commitments [Member]
Commitment and Contingencies [Line Items]
Operating lease right-of-use assets	$ 900	$ 900

Commitment and Contingencies _2

Commitment and Contingencies (Details) - Schedule of Company’s Supplemental Cash Flow Information Related to Leases $ in Thousands	8 Months Ended
	Sep. 30, 2024 USD ($)
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flow from operating leases	$ 74

Commitment and Contingencies _3

Commitment and Contingencies (Details) - Schedule of Company’s Operating Lease Liabilities Showing the Aggregate Lease Payments - USD ($) $ in Thousands	Sep. 30, 2024	Feb. 06, 2024
Schedule of Company’s Operating Lease Liabilities Showing the Aggregate Lease Payments [Abstract]
2024 (remainder)	$ 63
2025	369
2026	494
2027	380
Total undiscounted lease payments	1,306
Less: imputed interest	(318)
Total discounted lease payments	988
Less: current portion of lease liability	(146)
Non-current portion of lease liability	$ 842

Net Loss Per Share (Details)

Net Loss Per Share (Details) - shares	3 Months Ended	8 Months Ended
	Sep. 30, 2024	Sep. 30, 2024
Series A Preferred Stock [Member]
Net Loss Per Share (Details) [Line Items]
Weighted-average number of shares of as-converted	477,196	184,462
Series B Preferred Stock [Member]
Net Loss Per Share (Details) [Line Items]
Weighted-average number of shares of as-converted	4,099,227	1,584,575

Net Loss Per Share (Details) -

Net Loss Per Share (Details) - Schedule of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended	8 Months Ended
		Sep. 30, 2024	Sep. 30, 2024
Loss Allocation [Member]
Schedule of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders [Line Items]
Loss Allocation (in Dollars)		$ (28,623)	$ (57,943)
Loss Allocation [Member] | Series A Preferred Stock [Member]
Schedule of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders [Line Items]
Loss Allocation (in Dollars)	[1]	(697)	(1,121)
Loss Allocation [Member] | Series B Preferred Stock [Member]
Schedule of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders [Line Items]
Loss Allocation (in Dollars)	[2]	(5,990)	(9,630)
Loss Allocation [Member] | Common Stock [Member]
Schedule of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders [Line Items]
Loss Allocation (in Dollars)		$ (21,936)	$ (47,192)
Weighted Average Shares Outstanding [Member] | Series A Preferred Stock [Member]
Schedule of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders [Line Items]
Weighted Average Shares Outstanding (in Shares)	[1]	477	184
Weighted Average Shares Outstanding [Member] | Series B Preferred Stock [Member]
Schedule of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders [Line Items]
Weighted Average Shares Outstanding (in Shares)	[2]	49,191	19,015
Weighted Average Shares Outstanding [Member] | Common Stock [Member]
Schedule of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders [Line Items]
Weighted Average Shares Outstanding (in Shares)		15,013,655	7,765,381
Loss Per Share Basic [Member] | Series A Preferred Stock [Member]
Schedule of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders [Line Items]
Loss per share – basic	[1]	$ (1,460.62)	$ (6,077.13)
Loss Per Share Basic [Member] | Series B Preferred Stock [Member]
Schedule of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders [Line Items]
Loss per share – basic	[2]	(121.77)	(506.44)
Loss Per Share Basic [Member] | Common Stock [Member]
Schedule of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders [Line Items]
Loss per share – basic		(1.46)	(6.08)
Loss Per Share Diluted [Member] | Series A Preferred Stock [Member]
Schedule of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders [Line Items]
Loss per share – diluted	[1]	(1,460.62)	(6,077.13)
Loss Per Share Diluted [Member] | Series B Preferred Stock [Member]
Schedule of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders [Line Items]
Loss per share – diluted	[2]	(121.77)	(506.44)
Loss Per Share Diluted [Member] | Common Stock [Member]
Schedule of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders [Line Items]
Loss per share – diluted		$ (1.46)	$ (6.08)
[1] The weighted-average number of shares of as-converted Company Series A Preferred Stock used in the loss allocation was 477,196 and 184,462 for the three months ended September 30, 2024 and for the period from February 6, 2024 (inception) to September 30, 2024, respectively. The weighted-average number of shares of as-converted Company Series B Preferred Stock used in the loss allocation was 4,099,227 and 1,584,575 for the three months ended September 30, 2024 and for the period from February 6, 2024 (inception) to September 30, 2024, respectively.

Net Loss Per Share (Details) _2

Net Loss Per Share (Details) - Schedule of Anti-Dilutive Effect Excluded from Potential Computation of Diluted Net Loss Per Share - shares	3 Months Ended	8 Months Ended
	Sep. 30, 2024	Sep. 30, 2024
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total anti-dilutive securities	6,549,671	6,549,671
Outstanding Employee Warrants to Purchase Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total anti-dilutive securities	3,054,358	3,054,358
Outstanding Unvested Restricted Stock Awards [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total anti-dilutive securities	2,207,553	2,207,553
Outstanding and Issued Common Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total anti-dilutive securities	1,287,760	1,287,760

Related Party Transactions (Det

Related Party Transactions (Details) - Related Party [Member]	Sep. 30, 2024
Paragon and Paruka [Member]
Related Party Transactions [Line Items]
Own capital percentage	5%
Fairmount [Member]
Related Party Transactions [Line Items]
Own capital percentage	5%
Common Stock [Member] | Paragon and Paruka [Member]
Related Party Transactions [Line Items]
Own capital percentage	5%

Related Party Transactions (D_2

Related Party Transactions (Details) - Schedule of Related Party Accounts Payable and Other Current Liabilities - USD ($) $ in Thousands	Sep. 30, 2024	Feb. 06, 2024
Related Party [Member]
Condensed Financial Statements, Captions [Line Items]
Related party accounts payable and other current liabilities	$ 6,357
Paragon reimbursable Option Agreements’ fees [Member]
Condensed Financial Statements, Captions [Line Items]
Related party accounts payable and other current liabilities	6,140
Paragon reimbursable other research expenses [Member]
Condensed Financial Statements, Captions [Line Items]
Related party accounts payable and other current liabilities	146
Paragon reimbursable patent expenses [Member]
Condensed Financial Statements, Captions [Line Items]
Related party accounts payable and other current liabilities	$ 71