Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 65,917	$ 72,026
Marketable securities	9,464	12,015
Accounts receivable	1,205	215
Prepaid expenses and other current assets	464	686
Total current assets	77,050	84,942
Property, plant and equipment, net	2,353	2,476
Total assets	79,403	87,418
Current liabilities:
Accounts payable and accrued expenses (note 7)	1,530	2,664
Deferred revenue	8,724	11,622
Total current liabilities	10,254	14,286
Deferred revenue, less current portion		157
Deferred tenant inducements	180	196
Total liabilities	10,434	14,639
Shareholders’ equity:
Common shares, without par value; unlimited shares authorized; issued and outstanding: 14,222,275 (December 31, 2014 - 14,181,333)	147,508	147,157
Additional paid-in capital	30,450	30,346
Accumulated deficit	(107,999)	(103,734)
Accumulated other comprehensive loss	(990)	(990)
Shareholders’ equity	68,969	72,779
Total liabilities and shareholders’ equity	79,403	87,418
Commitments and contingencies (note 10)