Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 52,180	$ 67,754
Marketable securities	58,249	51,552
Accounts receivable	132	151
Prepaid expenses and other current assets	1,486	1,875
Total current assets	112,047	121,332
Operating lease right-of-use asset (note 6)	1,233
Property, plant and equipment, net	1,198	991
Deferred tax assets (note 10)	72	105
Total assets	114,550	122,428
Current liabilities:
Accounts payable and accrued expenses (note 7)	5,794	4,119
Current portion of operating lease liability (note 6)	582
Total current liabilities	6,376	4,119
Operating lease liability (note 6)	722
Loan payable, long-term (note 8)	15,139	15,014
Total liabilities	22,237	19,133
Shareholders’ equity:
Preferred shares, without par value; unlimited shares authorized; issued and outstanding: 1,016,000 (December 31, 2018 - 1,016,000) (note 9)	7,732	7,732
Common shares, without par value; unlimited shares authorized; issued and outstanding: 25,771,954 (December 31, 2018 - 25,750,721) (note 9)	266,040	265,923
Additional paid-in capital	38,932	38,515
Accumulated deficit	(219,401)	(207,885)
Accumulated other comprehensive loss	(990)	(990)
Shareholders' equity	92,313	103,295
Total liabilities and shareholders’ equity	114,550	122,428
Commitments and contingencies (note 11)