Pieris Pharmaceuticals, Inc. Annual report pursuant to Section 13 and 15(d)

Annual report pursuant to Section 13 and 15(d)

Note 9 - Stockholders' Equity (Details Textual)

Note 9 - Stockholders' Equity (Details Textual) $ / shares in Units, $ in Millions								1 Months Ended			12 Months Ended
	Jun. 20, 2023 shares	Jun. 22, 2022 shares	Jun. 25, 2021 shares	May 20, 2021 $ / shares shares	Apr. 01, 2020 shares	Jan. 30, 2019 shares	Jun. 01, 2016 USD ($) shares	Nov. 30, 2022 USD ($)	Aug. 31, 2021 USD ($) $ / shares	Nov. 30, 2019 USD ($) $ / shares shares	Dec. 31, 2023 USD ($) $ / shares shares	Dec. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2021 $ / shares	Jun. 30, 2016 $ / shares
Common Stock, Shares Authorized (in shares)											300,000,000	300,000,000
Common Stock, Shares, Issued (in shares)											98,935,025	74,519,103
Common Stock, Par or Stated Value Per Share (in dollars per share) \| $ / shares											$ 0.001	$ 0.001
Preferred Stock, Shares Authorized (in shares)											10,000,000	10,000,000
Preferred Stock, Shares Issued (in shares)											15,617	15,617
Preferred Stock, Par or Stated Value Per Share (in dollars per share) \| $ / shares											$ 0.001	$ 0.001
Preferred Stock, Shares Outstanding, Ending Balance (in shares)											15,617	15,617
Common Stock, Shares, Outstanding (in shares)											98,935,025	74,519,103
Jefferies L L C [Member]
Common Stock, Par or Stated Value Per Share (in dollars per share) \| $ / shares									$ 0.001
Conversion of Common Stock into Series E Preferred Stock [Member]
Conversion of Stock, Shares Converted (in shares)				5,000,000
Conversion of Stock, Shares Issued (in shares)				5,000
Employee Director And Consultant Equity Incentive Plan2020 [Member]
Sale of Stock, Number of Shares Issued in Transaction (in shares)					3,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized (in shares)	6,000,000	3,000,000	2,250,000		3,000,000
Securities Purchase Agreement [Member]
Preferred Stock, Shares Issued (in shares)							4,963
Partners' Capital Account, Units, Sold in Private Placement (in shares)							8,188,804
Shares Issued, Price Per Share (in dollars per share) \| $ / shares														$ 2.015
Proceeds from Issuance of Private Placement \| $							$ 16.5
Proceeds From Issuance Of Private Placement Net \| $							$ 15.3
Sale of Stock, Number of Shares Issued in Transaction (in shares)							3,225,804
At the Market Offering [Member] \| Jefferies L L C [Member]
Shares Issued, Price Per Share (in dollars per share) \| $ / shares											$ 0.84
Sale of Stock, Price Per Share (in dollars per share) \| $ / shares													$ 3.46
Sale of Stock, Authorized Amount \| $								$ 75.0	$ 50.0
Stock Issued During Period, Shares, New Issues (in shares)											24,300,000	2,100,000
Stock Issued During Period, Value, Issued for Services \| $											$ 20.3	$ 7.2
Common Stock [Member]
Number Of Votes Per Share											1
Stock Issued During Period, Shares, New Issues (in shares)											24,261,000
Common Stock [Member] \| Stock Exchange Shares from Existing Shareholders [Member]
Sale of Stock, Number of Shares Issued in Transaction (in shares)						5,000,000
Common Stock [Member] \| At the Market Offering [Member]
Stock Issued During Period, Shares, New Issues (in shares)												2,069,000
Preferred Stock [Member]
Stock Issued During Period, Shares, New Issues (in shares)											0
Preferred Stock [Member] \| Preferred Share Exchange [Member]
Sale of Stock, Number of Shares Issued in Transaction (in shares)						5,000
Preferred Stock [Member] \| At the Market Offering [Member]
Stock Issued During Period, Shares, New Issues (in shares)												0
Series A Preferred Stock [Member]
Preferred Stock, Shares Issued (in shares)											85	85
Preferred Stock, Shares Outstanding, Ending Balance (in shares)											85	85
Series B Preferred Stock [Member]
Preferred Stock, Shares Issued (in shares)											4,026	4,026
Preferred Stock, Shares Outstanding, Ending Balance (in shares)											4,026	4,026
Series C Preferred Stock [Member]
Preferred Stock, Shares Issued (in shares)											3,506	3,506
Preferred Stock, Shares Outstanding, Ending Balance (in shares)											3,506	3,506
Series C Preferred Stock [Member] \| Preferred Share Exchange [Member]
Sale of Stock, Price Per Share (in dollars per share) \| $ / shares										$ 3.43
Debt Instrument, Convertible, Beneficial Conversion Feature \| $										$ 2.8
Series C Preferred Stock [Member] \| Private Placement [Member]
Convertible Preferred Stock, Shares Issued upon Conversion (in shares)										0.001
Proceeds From Issuance Of Private Placement Net \| $										$ 31.0
Sale of Stock, Number of Shares Issued in Transaction (in shares)										9,014,960
Sale of Stock, Price Per Share (in dollars per share) \| $ / shares										$ 3.55
Sale of Stock, Consideration Received Per Transaction \| $										$ 32.0
Stock Issued During Period, Shares, Conversion of Units (in shares)										1
Sale of Stock, Number of Warrants, Per Unit (in shares)										1
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)										1
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) \| $ / shares										$ 7.1
Convertible Preferred Stock, Weighted Average Stock Price, Percent										3.00%
Series C Preferred Stock [Member] \| Private Placement [Member] \| Maximum [Member]
Warrants and Rights Outstanding, Term (Year)										5 years
Series D Preferred Stock [Member]
Preferred Stock, Shares Issued (in shares)											3,000	3,000
Preferred Stock, Shares Outstanding, Ending Balance (in shares)											3,000	3,000
Series E Preferred Stock [Member]
Preferred Stock, Shares Issued (in shares)											5,000	5,000
Preferred Stock, Shares Outstanding, Ending Balance (in shares)											5,000	5,000
Series A Through E [Member] \| Preferred Stock [Member]
Preferred Stock, Par or Stated Value Per Share (in dollars per share) \| $ / shares				$ 0.001
Convertible Preferred Stock, Shares Issued upon Conversion (in shares)				1,000
Convertible Preferred Stock, Common Stock Ownership Limit, Percent				9.99%
Convertible Preferred Stock, Beneficial Ownership Limitation, Percent				19.99%
Convertible Preferred Stock, Beneficial Ownership Limitation, Notice Period Before Increase (Year)				61 years