Condensed Balance Sheets (Parenthetical) (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	24,794,114	24,794,114
Common stock, shares issued	3,566,923	3,412,366
Common stock, shares outstanding	3,566,923	3,412,366
Series A Redeemable Convertible Preferred Stock
Redeemable convertible preferred stock, par value	$ 0.001	$ 0.001
Redeemable convertible preferred stock, shares authorized	9,008,931	9,008,931
Redeemable convertible preferred stock, shares issued	9,008,919	9,008,919
Redeemable convertible preferred stock, shares outstanding	9,008,919	9,008,919
Redeemable convertible preferred stock, liquidation preference	$ 17,178	$ 17,178
Series B Redeemable Convertible Preferred Stock
Redeemable convertible preferred stock, par value	$ 0.001	$ 0.001
Redeemable convertible preferred stock, shares authorized	9,430,145	9,430,145
Redeemable convertible preferred stock, shares issued	9,152,108	9,152,108
Redeemable convertible preferred stock, shares outstanding	9,152,108	9,152,108
Redeemable convertible preferred stock, liquidation preference	$ 87,972	$ 87,972

Face amount or stated value per share of common stock.

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