Area of real estate property sublease additional office facilities.

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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 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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Indicates line item in statement of financial position that includes noncurrent 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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The number of positions eliminated during the period as a result of restructuring activities.

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Commitments and Contingencies (Details Textual) € in Millions			1 Months Ended		12 Months Ended
	Nov. 30, 2023	Aug. 29, 2020 ft²	Jul. 31, 2021 EUR (€)	Jun. 30, 2021 ft²	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($) Employee
Commitments And Contingencies [Line Items]
Amount of retention bonuses					$ 311,000
Workforce reduction, percentage						67.00%
Workforce reduction, number of employees \| Employee						12
Percentage of retention bonuses	50.00%
Retention bonus paid					86,000
Severance expense					159,000
Restructuring Reserve, Current					$ 0
Area of office facilities taken on lease \| ft²		5,200
Operating lease term		42 months
Additional operating lease term		36 months
Lease renewal option		option to renew for an additional 36 month term at the then prevailing rental rate.
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					$ 127,000	$ 131,000
Lease liability					$ 280,000
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]					Accrued expenses and other liabilities (related party - $0 and $216 at December 31, 2023 and 2022, respectively)
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]					Operating lease liability, net of current portion
Weighted-average remaining lease term					3 years 2 months 12 days
Weighted-average discount rate					7.00%
Clinical development decisions
Commitments And Contingencies [Line Items]
Amount of retention bonuses						265,000
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
General and Administrative Expense
Commitments And Contingencies [Line Items]
Rent expense					$ 119,000	125,000
One-time Termination Benefits
Commitments And Contingencies [Line Items]
Restructuring charges						755,000
One-time Termination Benefits \| Research and development
Commitments And Contingencies [Line Items]
Restructuring charges						470,000
One-time Termination Benefits \| General and Administrative Expense
Commitments And Contingencies [Line Items]
Restructuring charges						$ 285,000