Note 7 - Accrued Expenses - Summary of Accrued Expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Accrued clinical trial costs	$ 4,600	$ 4,885
Accrued payroll and related costs	1,792	1,957
Accrued consulting and service fee expenses	1,314	1,026
Accrued legal and professional fees	788	1,123
Accrued contract manufacturing costs	665	2,048
Loss contingency for litigation		4,000
Other	945	751
Accrued expenses	$ 10,104	$ 15,790