Area of real estate property sublease additional office facilities.

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Commitments and contingencies.

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Lessee operating sublease term of contract.

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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 discount rate for operating lease calculated at point in time.

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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		3 Months Ended		12 Months Ended
	Nov. 30, 2023	Jul. 31, 2021 EUR (€)	Jun. 30, 2021 ft²	Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)	Apr. 20, 2024 USD ($)	Dec. 31, 2022 USD ($)	Aug. 29, 2020 ft²
Commitments And Contingencies [Line Items]
Amount of retention bonuses				$ 311,000
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				$ 23,000	$ 33,000
Lease liability				$ 48,000
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]				Accrued expenses and other liabilities
Weighted-average remaining lease term				6 months
Weighted-average discount rate				7.00%
Subsequent Event
Commitments And Contingencies [Line Items]
Amount of retention bonuses							$ 444,000
General and Administrative Expense
Commitments And Contingencies [Line Items]
Rent expense				$ 22,000	$ 31,000
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