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Nature of Business (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
	Feb. 28, 2021	Mar. 31, 2021	Dec. 31, 2020
Nature of Business
Accumulated deficit		$ (415,577)	$ (459,327)
Proceeds From Sale Of Priority Review Voucher	$ 100,000	100,000
Revenue		35
Carrying amount of cash and cash equivalents and short term investments		$ 404,750	$ 172,792

X

- Definition

The cash inflow from the sale of priority review voucher. Priority Review Vouchers (PRVs) which allow its recipient to expedite the review of any one of its new drug products.

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Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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