CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
OPERATING EXPENSES:
RESEARCH AND DEVELOPMENT EXPENSES	$ 16,588	$ 9,726
SELLING, GENERAL AND ADMINISTRATIVE EXPENSES	21,973	12,707
OPERATING LOSS	(38,561)	(22,433)
INTEREST AND OTHER INCOME, NET	768	989
NET LOSS	(37,793)	(21,444)
STATEMENTS OF COMPREHENSIVE LOSS
NET LOSS	(37,793)	(21,444)
OTHER COMPREHENSIVE INCOME:
UNREALIZED GAIN ON MARKETABLE SECURITIES	35
COMPREHENSIVE LOSS	$ (37,758)	$ (21,444)
NET LOSS PER ORDINARY SHARE BASIC AND DILUTED	$ 1.79	$ 1.11
WEIGHTED AVERAGE NUMBER OF SHARES OUTSTANDING USED IN COMPUTATION OF BASIC AND DILUTED LOSS PER ORDINARY SHARE	21,158,161	19,340,082

Interest and other Income (expenses) net.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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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 after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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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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