Equity Incentive Awards (Tables)

12 Months Ended

Dec. 31, 2023

Share-Based Payment Arrangement [Abstract]

Summary of Stock Option Activity

Stock Options. The following is a summary of stock option activity under Lexicon’s equity incentive plans for the year ended December 31, 2023:

	As of December 31, 2023
(in thousands, except exercise price data)	Options	Weighted Average Exercise Price
Outstanding at beginning of year	12,349	$	5.10
Granted	8,091	2.29
Exercised	—	—
Expired	(152)	14.68
Forfeited	(1,583)	3.66
Outstanding at end of year	18,705	3.93
Exercisable at end of year	8,280	$	5.58

Summary of Weighted-Average Stock Options Assumptions

The following weighted-average assumptions were used for stock options granted in the years ended December 31, 2023, 2022 and 2021, respectively:

	Expected Volatility	Risk-free Interest Rate	Expected Term	Dividend Rate
December 31, 2023:
Employees	110%	3.9%	4	0	%
Officers and non-employee directors	98%	4.0%	6	0	%
December 31, 2022:
Employees	109%	2.8%	4	0	%
Officers and non-employee directors	91%	1.9%	7	0	%
December 31, 2021:
Employees	104%	0.7%	4	0	%
Officers and non-employee directors	90%	1%	6	0	%

Summary of Restricted Stock Units Activity

The following is a summary of restricted stock units activity under Lexicon’s stock-based compensation plans for the year ended December 31, 2023:

	Shares	Weighted Average Grant Date Fair Value
	(in thousands)
Outstanding at December 31, 2022	2,748	$	3.78
Granted	4,199	2.43
Vested	(1,291)	3.80
Forfeited	(641)	2.72
Outstanding at December 31, 2023	5,015	$	2.78