Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 20,160	$ 17,095
Marketable securities	37,867	47,051
Accounts receivable	189	200
Prepaid expenses and other current assets	925	1,329
Total current assets	59,141	65,675
Prepaid expenses, long term	269	408
Property, plant and equipment, net	1,376	1,404
Total assets	60,786	67,487
Current liabilities:
Accounts payable and accrued expenses (note 6)	3,591	3,586
Total liabilities	3,591	3,586
Shareholders’ equity:
Common shares, without par value; unlimited shares authorized; issued and outstanding: 17,996,680 (December 31, 2016 - 17,930,590) (note 7a)	173,829	173,246
Additional paid-in capital	34,557	34,326
Accumulated deficit	(150,201)	(142,681)
Accumulated other comprehensive loss	(990)	(990)
Shareholders' equity	57,195	63,901
Total liabilities and shareholders’ equity	60,786	67,487
Commitments and contingencies (note 9)

Sum of the carrying values as of the balance sheet date of obligations incurred through that date and due within one year (or the operating cycle, if longer), including liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received, taxes, interest, rent and utilities, accrued salaries and bonuses, payroll taxes and fringe benefits.

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Balance Type:	credit
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- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.