Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 59,739	$ 105,138
Short-term investments	106,727	103,353
Accounts receivable, net	38,525	41,850
Inventory	42,629	41,905
Prepaid expenses and other current assets	24,668	21,950
Total current assets	272,288	314,196
Property and equipment, net	22,704	22,737
Right-of-use lease assets	15,594	16,277
Other assets	346	346
Total assets	310,932	353,556
Current liabilities:
Accounts payable	1,689	525
Accrued clinical and manufacturing liabilities	54,219	49,962
Accrued payroll and employee liabilities	9,629	13,597
Other accrued liabilities	24,744	28,369
Current lease liabilities	3,081	2,997
Convertible notes payable to related parties, net of discount	7,555	7,053
Total current liabilities	100,917	102,503
Non-current lease liabilities	13,790	14,561
Total liabilities	114,707	117,064
Stockholders’ equity:
Common stock	914	913
Additional paid-in capital	1,640,552	1,628,070
Accumulated other comprehensive income	121	257
Accumulated deficit	(1,445,362)	(1,392,748)
Total stockholders’ equity	196,225	236,492
Total liabilities and stockholders’ equity	$ 310,932	$ 353,556