Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash flows from operating activities:
Net loss	$ (53,478,812)	$ (28,059,807)	$ (15,528,269)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	28,834	11,126	8,316
Stock‑based compensation	4,983,023	1,345,722	329,184
Amortization of right of use lease asset	200,776	159,128
Foreign currency loss (gain)	890,252	(1,328,140)	(961,316)
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(472,402)	(2,633,732)	(19,452)
Accounts payable	2,326,767	437,515	214,380
Accrued expenses and other liabilities	3,928,684	3,513,782	706,923
Lease liability	(209,794)	(154,301)
Net cash used in operating activities	(41,802,672)	(26,708,707)	(15,250,234)
Cash flows from investing activities:
Purchases of property and equipment	(25,709)	(30,901)	(3,702)
Net cash used in investing activities	(25,709)	(30,901)	(3,702)
Cash flows from financing activities:
Proceeds from the exercise of stock options	150,949	70,997	2,097
Proceeds from issuance of common stock in initial public offering, net		86,906,179
Net cash provided by financing activities	150,949	92,575,538	56,366,742
Decrease in cash and cash equivalents	(41,677,432)	65,835,930	41,112,806
Effect of exchange rate changes on cash	606,249	(1,422,992)	161,637
Cash and cash equivalents—beginning of year	130,088,869	65,675,931	24,401,488
Cash and cash equivalents—end of year	$ 89,017,686	130,088,869	65,675,931
Series C convertible preferred stock
Cash flows from financing activities:
Proceeds from issuance of Series C convertible preferred, net		$ 5,598,362	$ 56,364,645