Nature of the Business	9 Months Ended
Sep. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of The Business	1. Nature of the Business Organization Arcellx, Inc. (Arcellx or the Company) was incorporated in Delaware in December 2014 and is headquartered in Redwood City, California. The Company is a clinical-stage biopharmaceutical company reimagining cell therapy through the development of innovative therapies for patients with cancer and other incurable diseases. Liquidity As of September 30, 2024, the Company had $676.7 million of cash, cash equivalents and marketable securities, which management believes will be sufficient to meet the Company’s anticipated operating and capital expenditure requirements for at least twelve months following the date of issuance of these condensed consolidated financial statements.

The entire disclosure for the nature of an entity's business, major products or services, principal markets including location, and the relative importance of its operations in each business and the basis for the determination, including but not limited to, assets, revenues, or earnings. For an entity that has not commenced principal operations, disclosures about the risks and uncertainties related to the activities in which the entity is currently engaged and an understanding of what those activities are being directed toward.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Topic 275
-Publisher FASB
-URI https://asc.fasb.org/275/tableOfContent

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-SubTopic 10
-Topic 275
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-1

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