Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2022

Business

Schedule of percentages of revenue recognized from license agreement partners

The percentages of revenue recognized from license agreement partners of the Company in the years ended December 31, 2022, 2021 and 2020 are included in the following table:

	Revenue
	Year Ended December 31,
	2022		2021		2020
License Agreement Partner:
CSL Vifor*	100	%	92	%	100	%

______________

* Includes amounts earned from Vifor Fresenius Medical Care Renal Pharma Ltd. and Vifor International prior to Vifor International’s assignment of its rights and obligations to Vifor Fresenius Medical Care Renal Pharma Ltd. in May 2022.

Summary of Useful Lives of Property and Equipment

Property and equipment (consisting of computer and office equipment, furniture and fixtures and leasehold improvements) are stated at cost, net of accumulated depreciation and amortization of leasehold improvements. Depreciation and amortization are calculated using the straight-line method over the estimated useful lives of the respective assets. Leasehold improvements are amortized over the lesser of their useful lives or the life of the lease.

Asset Category	Useful Lives
Computer and office equipment	5 years
Furniture and fixtures	7 years
Leasehold improvements	lesser of useful life of asset or life of lease (Stamford - 7 years)