Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 10,586	$ 7,851
Prepaid expenses	178	607
Total current assets	10,764	8,458
Property and equipment, net	13,906	13,916
Right of use and other assets	250	18
Total assets	24,920	22,392
Current liabilities:
Accounts payable	804	875
Accrued expenses	803	1,343
Lease liability, current portion	167
Total current liabilities	1,774	2,218
Lease liability, long-term	82
Commitments and contingencies (Note 11)
Stockholders' equity
Common stock, $.0001 par value, 150,000,000 shares authorized, 44,632,329 and 34,377,329 issued and outstanding at June 30, 2019 and December 31, 2018, respectively	4	3
Additional paid-in capital	272,977	261,722
Accumulated deficit	(249,917)	(241,551)
Total stockholders' equity	23,064	20,174
Total liabilities and stockholders' equity	$ 24,920	$ 22,392

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).

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Balance Type:	credit
Period Type:	instant

- Definition

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).