Area of real estate property sublease additional office facilities.

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Commitments and contingencies.

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Operating lease extended expiry year and month.

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Percentage of base rent to be paid monthly.

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Percentage of retention bonuses.

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Potential upfront and milestone obligations and royalty obligations.

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Retention bonus paid.

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Retention bonuses.

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Area of a real estate property.

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Description of assumptions and judgments used by lessee for allocating contract between lease and nonlease components for operating lease.

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Indicates (true false) whether lessee has option to extend operating lease.

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Description of terms and conditions of option to extend lessee's operating lease. Includes, but is not limited to, information about option recognized as part of right-of-use asset and lease liability.

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Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Indicates line item in statement of financial position that includes current operating lease liability.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Commitments and Contingencies (Details Textual) € in Millions		1 Months Ended			6 Months Ended		12 Months Ended
	Nov. 30, 2023	Mar. 31, 2024	Jul. 31, 2021 EUR (€)	Jun. 30, 2021 ft²	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Aug. 29, 2020 ft²
Commitments And Contingencies [Line Items]
Amount of retention bonuses					$ 444,000
Percentage of retention bonuses	50.00%
Retention bonus paid							$ 86,000
Restructuring Reserve, Current							0
Severance expense							$ 159,000
Area of office facilities taken on lease \| ft²									5,200
Operating lease term									42 months
Additional operating lease term		6 months
Lease renewal option					extend the lease term six (6) months through September 2024
Operating lease extended expiry		2024-09
Percentage of base rent to be paid monthly					125.00%
Lessee, Operating Lease, Existence of Option to Extend [true false]		true
Area of additional office facilities taken on sublease \| ft²				3,000
Operating sublease term				29 months
Lessee, operating lease, assumptions and judgments, allocation of lease and nonlease component					The leases include real estate taxes and insurance, which is not a lease component and is not included in the lease obligation. In addition, common area maintenance charges are based on actual costs incurred and are a non-lease component that is not included in the lease obligation.
Operating lease, cash paid for measurement of lease liabilities					$ 47,000	$ 67,000
Lease liability					$ 24,000
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]					Accrued expenses and other liabilities
Weighted-average remaining lease term					3 months 18 days
Weighted-average discount rate					7.00%
General and Administrative Expense
Commitments And Contingencies [Line Items]
Rent expense					$ 31,000	$ 63,000
Research and development \| Patent Assignment Agreement \| University Medical Center of Johannes Gutenberg University Mainz
Commitments And Contingencies [Line Items]
Potential upfront and milestone obligations and royalty obligations \| €			€ 1.6
Clinical development decisions
Commitments And Contingencies [Line Items]
Amount of retention bonuses								$ 265,000