Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Income Statement [Abstract]
Revenue	$ 0	$ 5,160
Operating expenses:
Research and development	26,742	15,523
General and administrative	7,369	4,508
Total operating expenses	34,111	20,031
Loss from operations	(34,111)	(14,871)
Other income, net	0	1
Interest income	1,612	1,183
Net loss	$ (32,499)	$ (13,687)
Net loss per share, basic and diluted	$ (0.99)	$ (0.57)
Weighted-average shares used to calculate net loss per share, basic and diluted	32,993,753	23,866,066

The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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