Subsequent Events	9 Months Ended
Sep. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	16. Subsequent Events In October 2021, the Company and its President and Chief Executive Officer, or CEO, agreed to the transition of the role from CEO to Senior Advisor beginning on November 9, 2021. In addition, the Company and the CEO entered into a Separation Agreement dated November 2, 2021, pursuant to which the CEO will provide transitional consulting services as a Senior Advisor to the Company from November 9, 2021 through June 30, 2022. The Company appointed a current non-employee director of the Company’s Board of Directors to the position of Senior Advisor, effective October 29, 2021 until November 8, 2021, and as President and CEO, effective as of November 9, 2021. In October 2021, after the expiration of the requisite waiting period under the HSR Act, the Company received the $50,000 milestone payment from Vifor and issued 3,282,391 shares of its common stock to Vifor at a price of $15.23 per share, in connection with U.S. regulatory approval of KORSUVA injection on August 23, 2021. In October 2021, the Company received the $15,000 milestone payment from VFMCRP.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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