v3.22.4

Document And Entity Information	Feb. 23, 2023
Document Information [Line Items]
Document Type	8-K
Amendment Flag	false
Document Period End Date	Feb. 23, 2023
Entity Registrant Name	Apexigen, Inc.
Entity Central Index Key	0001814140
Entity Emerging Growth Company	true
Securities Act File Number	001-39488
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	85-1260244
Entity Address, Address Line One	75 Shoreway Road
Entity Address, Address Line Two	Suite C
Entity Address, City or Town	San Carlos
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94070
City Area Code	(650)
Local Phone Number	931-6236
Written Communications	false
Soliciting Material	false
Pre-commencement Tender Offer	false
Pre-commencement Issuer Tender Offer	false
Entity Ex Transition Period	false
Warrants Each Whole Warrant Exercisable For One Share Of Common Stock At An Exercise Price Of 11.50 Per Share [Member]
Document Information [Line Items]
Title of 12(b) Security	Warrants, each whole warrant exercisable for one share of Common Stock at an exercise price of $11.50 per share
Trading Symbol	APGNW
Security Exchange Name	NASDAQ
Common Stock 0.0001 Par Value Per Share [Member]
Document Information [Line Items]
Title of 12(b) Security	Common Stock, $0.0001 par value per share
Trading Symbol	APGN
Security Exchange Name	NASDAQ

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For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.

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The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

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Address Line 1 such as Attn, Building Name, Street Name

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A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

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The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Apexigen, Inc. 8-K