Balance Sheets - USD ($)	Jun. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 149,844,590	$ 158,201,441
Prepaid expenses and other current assets	3,513,405	4,326,322
Total current assets	153,357,995	162,527,763
Property and equipment, net	708,159	822,920
Prepaid research and development expenses	1,560,607	1,560,607
Deposits	52,320	52,320
Operating lease right-of-use asset	2,673,656	3,006,069
Total assets	158,352,737	167,969,679
Current liabilities:
Accounts payable	1,371,308	1,435,660
Accrued expenses	7,479,793	8,710,790
Operating lease liabilities	850,188	804,126
Total current liabilities	9,701,289	10,950,576
Noncurrent accrued expenses	515,144
Noncurrent operating lease liabilities	2,383,808	2,818,516
Total liabilities	12,600,241	13,769,092
Stockholders' equity:
Preferred stock; $0.001 par value; 5,000,000 shares authorized, no shares issued and outstanding at June 30, 2020 and December 31, 2019
Common stock; $0.001 par value; 100,000,000 shares authorized; 46,714,698 shares issued and outstanding at June 30, 2020; 43,466,933 shares issued and outstanding at December 31, 2019	46,713	43,465
Additional paid-in capital	425,890,066	412,599,772
Accumulated deficit	(280,184,283)	(258,442,650)
Total stockholders' equity	145,752,496	154,200,587
Total liabilities and stockholders' equity	$ 158,352,737	$ 167,969,679

Sum of the carrying values as of the balance sheet date of obligations incurred through that date and due after one year (or beyond the operating cycle if longer), including liabilities for compensation costs, fringe benefits other than pension and postretirement obligations, rent, contractual rights and obligations, and statutory obligations.

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Period Type:	instant

- Definition

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).