Certain Balance Sheet Items

12 Months Ended

Dec. 31, 2023

Balance Sheet Related Disclosures [Abstract]

Accounts receivable, net and contract assets consisted of the following (in thousands):


	December 31, 2023		December 31, 2022
Accounts receivable from product sales to partners	$	58,588	$	62,979
Accounts receivable from revenues under collaborative agreements	16,183		18,776
Accounts receivable from royalty payments	118,170		100,900
Accounts receivable from other product sales	47,060		6,229

Contract assets	956		44,102
Total accounts receivable and contract assets	240,957		232,986
Allowance for distribution fees and discounts	(6,747)		(1,914)
Total accounts receivable, net and contract assets	$	234,210	$	231,072

Inventories consisted of the following (in thousands):


	December 31, 2023		December 31, 2022
Raw materials	$	23,646	$	13,792
Work-in-process	34,025		40,361
Finished goods	69,930		45,970
Total inventories, net	$	127,601	$	100,123

Prepaid expenses and other assets consisted of the following (in thousands):


	December 31, 2023		December 31, 2022
Prepaid manufacturing expenses	$	36,850	$	51,694

Other prepaid expenses	12,902		4,647
Other assets	16,677		14,984
Total prepaid expenses and other assets	66,429		71,325
Less: Long-term portion	(17,816)		(26,301)
Total prepaid expenses and other assets, current	$	48,613	$	45,024

Prepaid manufacturing expenses include raw materials, slot reservation fees and other amounts paid to contract manufacturing organizations. Such amounts are reclassified to work-in-process inventory as materials are used or the contract manufacturing organization services are complete.

Property and equipment, net consisted of the following (in thousands):


	December 31, 2023		December 31, 2022
Research equipment	$	8,588	$	7,380
Manufacturing equipment	32,472		27,893
Computer and office equipment	9,722		7,855
Leasehold improvements	6,987		6,729
Subtotal	57,769		49,857
Accumulated depreciation and amortization	(19,661)		(14,756)
Subtotal	38,108		35,101
Right of use of assets	36,836		40,469
Property and equipment, net	$	74,944	$	75,570

Depreciation and amortization expense was approximately $11.1 million, $6.5 million, and $3.0 million, inclusive of ROU asset amortization of $5.5 million, $3.0 million and $1.6 million for the years ended December 31, 2023, 2022 and 2021, respectively.

Accrued expenses consisted of the following (in thousands):


	December 31, 2023		December 31, 2022

Accrued compensation and payroll taxes	$	17,361	$	19,939
Accrued outsourced manufacturing expenses	12,361		12,190
Income taxes payable	963		—
Product returns and sales allowance	41,932		30,261
Other accrued expenses	33,584		35,270
Lease liability	32,197		34,788
Total accrued expenses	138,398		132,448
Less long-term portion	(37,720)		(32,686)
Total accrued expenses, current	$	100,678	$	99,762

Expense associated with the accretion of the lease liabilities was approximately $2.5 million, $0.5 million and $0.3 million for the twelve months ended December 31, 2023, 2022 and 2021, respectively. Total lease expense for the twelve months ended December 31, 2023, 2022 and 2021 was $8.0 million, $3.3 million and $1.9 million, respectively.

Cash paid for amounts related to leases for the twelve months ended December 31, 2023, 2022 and 2021 was $6.7 million, $4.2 million and $2.7 million, respectively.