Subsequent Event	3 Months Ended
Mar. 31, 2021
Subsequent Events [Abstract]
Subsequent Event	10. Subsequent Event In April 2021, the Company dosed the first patient in its Phase 3 trial of AVB-500 in platinum resistant ovarian cancer. Based upon this event, the Company has completed its first clinical milestone with 3D Medicines and expects to receive a $6 million cash payment related to the completion of this milestone. A portion of collaboration revenue related to the completion of this milestone will be recorded in the second quarter of 2021 and the remaining amount will be deferred over the development period.

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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