Condensed Consolidating Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Expenses
Research and development	$ 1,525	$ 446	$ 3,045	$ 765
General and administrative	924	269	1,681	415
Total operating expenses	2,449	715	4,726	1,180
Loss from operations	(2,449)	(715)	(4,726)	(1,180)
Other Expense
Interest and other income (expense), net	173	(44)	300	(73)
Total interest and other income (expense), net	173	(44)	300	(73)
Net loss applicable to stockholders and members	(2,276)	(759)	(4,426)	(1,253)
Unrealized loss on available-for-sale securities	(2)		(2)
Comprehensive loss	$ (2,278)	$ (759)	$ (4,428)	$ (1,253)
Net loss attributable to common stockholders and members per share: Basic and diluted	$ (0.22)	$ (0.22)	$ (0.43)	$ (0.36)
Weighted-average common shares and common units outstanding: Basic and diluted	10,310,101	3,490,884	10,308,747	3,490,884

Interest income (expense) and other nonoperating, net.

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Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

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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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The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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The net result for the period of deducting operating expenses from operating revenues.

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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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