Subsequent Events	3 Months Ended
Mar. 31, 2020
Disclosure Text Block
Subsequent Events	16. Subsequent Events Collaboration with Roche On April 30, 2020, the Company entered into an eighth amendment to the Roche agreement, pursuant to which the Company and Roche agreed to, among other things, modify certain time periods related to Roche’s option rights for one of the collaboration programs and certain mechanics for deeming such collaboration program as a terminated target.

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

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