Investments and Fair Value Instruments (Tables)

9 Months Ended

Sep. 30, 2023

Investments And Fair Value Instruments [Abstract]

Summary of Amortized Cost and Fair Value of Investment Securities Portfolio

The following tables summarize the amortized cost and fair value of the investment securities portfolio at September 30, 2023 and December 31, 2022 and the corresponding amounts of unrealized gains and losses recognized in accumulated other comprehensive income:

(Dollars in thousands)	Amortized Cost		Unrealized Gains		Unrealized Losses		Estimated Fair Value
September 30, 2023
Cash equivalents:
Money market funds	$	8,672	$	—	$	—	$	8,672
Short-term investments:
Treasury bills		5,002		87		—		5,089
Total Assets at Fair Value	$	13,674	$	87	$	—	$	13,761

(Dollars in thousands)	Amortized Cost		Unrealized Gains		Unrealized Losses		Estimated Fair Value
December 31, 2022
Cash equivalents:
Money market funds	$	18,620	$	—	$	—	$	18,620
Total Assets at Fair Value	$	18,620	$	—	$	—	$	18,620

Summary of Fair Value of Investment Securities

The fair value of the investment securities at September 30, 2023 were as follows:

	Fair Value Measurements at September 30, 2023
(Dollars in thousands)	Level 1		Level 2		Level 3		Total
Assets at Fair Value
Cash equivalents:
Money market funds	$	8,672	$	—	$	—	$	8,672
Short-term investments:
Treasury bills		5,089		—		—		5,089
Total Assets at Fair Value	$	13,761	$	—	$	—	$	13,761

The fair value of the investment securities at December 31, 2022 were as follows:

	Fair Value Measurements at December 31, 2022
(Dollars in thousands)	Level 1		Level 2		Level 3		Total
Assets at Fair Value
Cash equivalents:
Money market funds	$	18,620	$	—	$	—	$	18,620
Total Assets at Fair Value	$	18,620	$	—	$	—	$	18,620

Summary of Preferred Investment Option Liabilities Measured and Recorded on Recurring Basis using Black-Scholes Model

The preferred investment option liabilities were measured and recorded on a recurring basis using the Black-Scholes Model with the following assumptions as of September 30, 2023 and December 31, 2022:

	March 2023 Options - Series A & March 2023 Placement Agent Options					March 2023 Options - Series B					August 2022 Options & August 2022 Placement Agent Options
	September 30, 2023			December 31, 2022		September 30, 2023			December 31, 2022		September 30, 2023			December 31, 2022
Remaining term (in years)		4.42			—		0.86			—		3.92			4.67
Expected volatility		106.3	%		—		89.9	%		—		92.2	%		106.2	%
Risk-free interest rate		4.7	%		—		5.5	%		—		4.7	%		4.0	%
Expected dividend yield		0	%		—		0	%		—		0	%		0	%

Summary of Changes in Fair Value and Other Adjustments of Liabilities

The following table sets forth the establishment of the Company’s Level 3 liabilities, as well as a summary of the changes in the fair value and other adjustments (in thousands):

(Dollars in thousands)	March 2023 Options - Series A			March 2023 Options - Series B			March 2023 Placement Agent Options			August 2022 Options			August 2022 Placement Agent Options			Contingent Liabilities		Total
Balance as of December 31, 2022	$	—		$	—		$	—		$	767		$	39		$	2,000	$	2,806
Initial recognition		4,324			2,274			212			—			—			—		6,810
Change in fair value and other adjustments		(2,934	)		(2,090	)		(146	)		(575	)		(35	)		—		(5,780	)
Balance as of September 30, 2023	$	1,390		$	184		$	66		$	192		$	4		$	2,000	$	3,836