Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 64,346	$ 72,026
Marketable securities	9,354	12,015
Accounts receivable	188	215
Prepaid expenses and other current assets	465	686
Total current assets	74,353	84,942
Property, plant and equipment, net	2,174	2,476
Total assets	76,527	87,418
Current liabilities:
Accounts payable and accrued expenses (note 7)	2,278	2,664
Deferred revenue	5,635	11,622
Fair value of liability classified stock options (note 3 and 6)	4,103
Total current liabilities	12,016	14,286
Deferred revenue, less current portion		157
Deferred tenant inducements	164	196
Total liabilities	12,180	14,639
Shareholders’ equity:
Common shares, without par value; unlimited shares authorized; issued and outstanding: 14,267,174 (December 31, 2014 - 14,181,333)	147,824	147,157
Additional paid-in capital	29,314	30,346
Accumulated deficit	(111,801)	(103,734)
Accumulated other comprehensive loss	(990)	(990)
Shareholders’ equity	64,347	72,779
Total liabilities and shareholders’ equity	$ 76,527	$ 87,418
Commitments and contingencies (note 10)