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Royalties payable description.

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License Agreements - Additional Information (Details) - USD ($)		1 Months Ended		3 Months Ended
	Jan. 12, 2021	Mar. 31, 2021	Mar. 31, 2019	Mar. 31, 2021	Mar. 31, 2020
George Washington
Research And Development Arrangement Contract To Perform For Others [Line Items]
Milestone payment					$ 500,000
Percentage of royalty on net sales				6.00%
Percentage of payments received from sublicensee				15.00%
Royalty payments				$ 2,800,000	$ 400,000
Harvard
Research And Development Arrangement Contract To Perform For Others [Line Items]
Percentage of royalty on net sales				5.00%
Percentage of payments received from sublicensee				20.00%
Clinical development and regulatory milestones amount payable				$ 15,100,000
Percentage of minimum royalty rate				4.50%
Percentage of maximum royalty based on achievement of annual net product sales thresholds				7.50%
Royalties payment				$ 100,000
Payments related to clinical development and regulatory milestones				0
Paratek
Research And Development Arrangement Contract To Perform For Others [Line Items]
Percentage of royalty on net sales			2.25%
Royalties payment				$ 51,000
Claim expiration				2023-10
PAION AG
Research And Development Arrangement Contract To Perform For Others [Line Items]
Milestone payment	$ 109,500,000
Upfront cash payment	$ 22,500,000
Percentage of refundable tax withholding	15.00%
Everest Medicines Limited
Research And Development Arrangement Contract To Perform For Others [Line Items]
Additional regulatory milestone payments receivable		$ 8,000,000.0		$ 8,000,000.0
Sales milestone payments receivable		20,000,000.0		$ 20,000,000.0
Royalties payable description				Royalties are payable with respect to each jurisdiction in the Everest Territory until the latest to occur of: (1) the last-to-expire of specified patent rights in such jurisdiction in the Everest Territory; (2) expiration of marketing or regulatory exclusivity in such jurisdiction in the Everest Territory; or (3) 10 years after the first commercial sale of a product in such jurisdiction in the Everest Territory.
Royalties payable period after first commercial sale of product				10 years
Milestone payments received		$ 3,000,000.0		$ 3,000,000.0