Equity Incentive Plans (Tables)

12 Months Ended

Dec. 31, 2023

Share-Based Payment Arrangement [Abstract]

Summary of the Option Award Activity

The following table summarizes the option activity for the years ended December 31, 2023 and 2022:

							Options Outstanding
											Weighted-
	Shares						Weighted		Weighted-		Average		Aggregate
	Available						Average		Average		Remaining		Intrinsic
	For			Number of			Exercise		Grant Date		Contractual Life		Value
	Grant			Options			Price		Fair Value		(in years)		(in thousands)
Balances, January 1, 2022		7,073			6,082		$	223.00	$	1.06		8.56	$	1,163
Shares reserved for issuance		4,858			—
Reserved shares cancelled		—			—
Options granted		(7,367	)		7,367		$	171.00	$	1.01
Options forfeited / cancelled		—			(188	)	$	100.00	$	0.44
Options expired		—			—		$	—	$	—
Options exercised		—			(563	)	$	100.00	$	0.44
Balances, December 31, 2022		4,564			12,698		$	200.00	$	1.06		7.77	$	62
Shares reserved for issuance		4,839			—
Reserved shares cancelled		—			—
Options granted		(5,750	)		5,750		$	12.68	$	0.12
Options forfeited / cancelled		3,537			(3,787	)	$	131.45	$	0.90
Options expired		—			—		$	—	$	—
Options exercised		—			—		$	—	$	—
Balances, December 31, 2023		7,190			14,661		$	144.41	$	0.74		7.42	$	—
At December 31, 2023
Vested and exercisable					6,110		$	199.12		0.97		6.27	$	—

Summary of Non-vested Restricted Common Stock Awards Issued to Employees

The following table sets forth the status of the Company’s non-vested restricted common stock awards issued to employees:

	Number of Shares			Weighted- Average Grant-Date Fair Value Per Share
Non-vested as of January 1, 2022		1,009		$	0.36
Vested		(71	)	$	0.36
Cancelled		(938	)	$	0.36
Non-vested as of December 31, 2022		—		$	—

Summary of Fair Value of Share-Based Payment Awards Estimated on Date of Grant using Assumptions

The fair value of share-based payment awards was estimated on the date of grant using the following assumptions:

	2023			2022
Expected life (in years)	5.71 – 6.08			3.58 – 6.08
Expected volatility	114.59% - 153.33%			49.86% - 114.76%
Risk-free interest rate	3.50% - 4.01%			0.99% - 3.85%
Dividend yield		—	%		—	%

Summary of Total Stock-based Compensation Expense Recorded Related to Share-based Payment Awards

Total stock-based compensation expense recorded related to share-based payment awards was allocated to research and development, sales and marketing, and general and administrative expense as follows (in thousands):

	2023		2022
Research and development	$	103	$	114
Sales and marketing		1		4
General and administrative		167		280
Total stock-based compensation	$	271	$	398