Financial Statement Details

12 Months Ended

Dec. 31, 2023

Financial Statement Details [Abstract]

Prepaid Expenses and Other Current Assets

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


	As of December 31,
	2023		2022

Prepaid research and development costs	$	7,847	$	11,704
Prepaid services	5,869		8,013
Prepaid insurance	2,242		2,282
Prepaid software license fees	2,100		2,195
Insurance premium financing asset	1,475		1,417


Insurance claims receivable	1,149		—
Prepaid equipment maintenance	1,183		833
ERP system implementation cost	1,087		920




Prepaid supplies	—		2,160
Other	2,651		1,979
Prepaid expenses and other current assets	$	25,603	$	31,503

Property, Plant and Equipment, Net

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


	As of December 31,
	2023		2022

Leasehold improvements	$	72,552	$	68,710
Equipment	69,915		67,945
Construction in progress	84,436		72,693
Software	1,666		1,657
Furniture & fixtures	1,889		1,906
Gross property, plant and equipment	230,458		212,911
Less: Accumulated depreciation and amortization	84,376		69,252
Property, plant and equipment, net	$	146,082	$	143,659

During the years ended December 31, 2023, 2022 and 2021, depreciation expense related to property, plant and equipment totaled $16.5 million, $16.3 million and $14.2 million, respectively.

Intangible Assets, Net

The gross carrying amounts and accumulated amortization of intangible assets are as follows at the dates indicated (in thousands):


	December 31, 2023
	Weighted- Average Life (in years)	Gross Carrying Amount		Accumulated Amortization		Impairment		Net Carrying Amount

Definite-lived: Favorable leasehold rights	8.1	$	20,398	$	(3,825)	$	—	$	16,573
Indefinite-lived: IPR&D		1,406		—		(886)		520
Total intangible assets		$	21,804	$	(3,825)	$	(886)	$	17,093


	December 31, 2022
	Weighted- Average Life (in years)	Gross Carrying Amount		Accumulated Amortization		Impairment		Net Carrying Amount

Favorable leasehold rights	9.1	$	20,398	$	(1,785)	$	—	$	18,613
Organized workforce		831		(150)		(681)		—
Total definite-lived intangible assets		21,229		(1,935)		(681)		18,613
Indefinite-lived: IPR&D		1,390		—		—		1,390
Total intangible assets		$	22,619	$	(1,935)	$	(681)	$	20,003

Definite-Lived Intangible Assets

In connection with the acquisition of the Dunkirk Facility in 2022, we acquired definite-lived intangibles consisting of favorable leasehold rights and an organized workforce. During the year ended December 31, 2022, we wrote off the entire unamortized organized workforce intangible asset totaling $0.7 million in impairment of intangible assets, on the consolidated statement of operations. See Note 6, Collaboration and License Agreements and Acquisition, for more information.

During the years ended December 31, 2023 and 2022, we recorded amortization expense of definite-lived intangible assets totaling $2.0 million and $1.9 million, respectively, in research and development expense, on the consolidated statements of operations.

Indefinite-Lived Intangible Assets

During the year ended December 31, 2023, we discontinued the research and development program associated with the Tarmogen platform based on results gathered from clinical data. We recorded a charge totaling $0.9 million in impairment of intangible assets, on the consolidated statement of operations in connection with the writedown of the carrying value of Tarmogen to zero. No such impairments were recorded during the years ended December 31, 2022 and 2021. As of December 31, 2023 and 2022, the company had indefinite-lived IPR&D intangible assets of $0.5 million and $1.4 million, respectively, which were obtained from business acquisitions.

Future amortization expense associated with our definite-lived intangible assets is as follows (in thousands):


Years ending December 31:	Definite-lived Intangible Assets

2024	$	2,040
2025	2,040
2026	2,040
2027	2,040
2028	2,040
Thereafter	6,373
Total	$	16,573

Convertible Note Receivable

In 2016, we executed a convertible promissory note pursuant to which we advanced Riptide a principal amount of $5.0 million. The note bears interest at a per annum rate of five percent (5%). Concurrent with the transaction, we entered into an exclusive license agreement with Riptide to obtain worldwide exclusive rights, with the right to sublicense, certain know-how related to RP-182, RP-233 and RP-183. We are required to pay a single-digit royalty on net sales of the licensed products on a country-by-country basis. Pursuant to the license agreement, we are also required to make cash milestone payments upon successful completion of certain clinical, regulatory and commercial milestones up to an aggregate amount of $47.0 million for the first three indications of the licensed product with a maximum payment amount of $100.0 million.

In 2019, we entered into a first amendment to the convertible promissory note with Riptide. Under the agreement, we extended the maturity of the promissory note to the earlier of (a) the later of (i) the completion of non-clinical IND enabling studies by the company, or (ii) December 31, 2020; and (b) when we accelerate the maturity of the note upon the occurrence of an event of default. No other terms and conditions of the promissory note were modified. Concurrently, we also entered into a first amendment to the exclusive license agreement with Riptide and extended the achievement dates for certain clinical trial milestones related to the licensed products. This option for receiving a 25% discount was determined to have an immaterial value at inception and life-to-date of the note, as the probability of a future qualifying event is remote. The convertible note receivable balance was $6.9 million and $6.6 million, which included accrued interest of $1.9 million and $1.6 million as of December 31, 2023 and 2022, respectively.

Accrued Expenses and Other Liabilities

Accrued expenses and other liabilities consist of the following (in thousands):


	As of December 31,
	2023		2022


Accrued bonus	$	11,350	$	12,068
Accrued professional and service fees	9,829		6,685
Accrued research and development costs	7,700		1,930
Accrued compensation	6,241		6,040
Accrued preclinical and clinical trial costs	4,218		4,985
Financing obligation – current portion	1,475		1,417
Accrued construction costs	1,179		7,072


Other	716		1,628
Accrued expenses and other liabilities	$	42,708	$	41,825

Interest and Investment Income (Loss), Net

Interest and investment income (loss), net consists of the following (in thousands):


	Year Ended December 31,
	2023		2022		2021

Unrealized losses from equity securities	$	(1,591)	$	(4,190)	$	(4,615)
Interest income	863		2,708		836
Investment accretion income (amortization expense), net	1,844		(1,486)		(488)
Net realized gains (losses) on investments	15		(122)		167
Interest and investment income (loss), net	$	1,131	$	(3,090)	$	(4,100)

Interest income includes interest from marketable securities, convertible notes receivable, other assets, and on bank deposits.

Interest expense

Interest expense consists of the following (in thousands):


	Year Ended December 31,
	2023		2022		2021

Interest expense on related-party notes payable	$	86,453	$	47,145	$	14,695
Amortization of related-party notes discounts	42,396		16,282		62
Other interest expense	349		88		92
Interest expense	$	129,198	$	63,515	$	14,849