Subsequent Events	3 Months Ended
Mar. 31, 2021
Subsequent Events [Abstract]
Subsequent Events	10. Subsequent events In December 2015, the Company entered a lease agreement in Menlo Park, CA for laboratory and office space. In April 2021, the Company further extended the term of this operating lease for an additional two months, extending the lease end date to December 31, 2021, with an option to extend the term for one additional month to January 2022. In April 2021, the Company entered a new operating lease for laboratory and office space in Menlo Park, CA, which commenced on April 1, 2021. The lease will continue for 13 months. The Company’s total obligation over the new lease is approximately $0.4 million.

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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