Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Mar. 31, 2024	Jun. 30, 2023
Current assets
Cash and cash equivalents	$ 8,487	$ 14,208
Short-term investments	26,196	27,919
Accounts receivable	201	225
Inventory, net:
Raw materials	1,734	1,379
Work-in-process	251	243
Finished goods	359	373
Income tax receivable	0	1
Prepaid expenses and other current assets	274	365
Total current assets	37,502	44,713
Property and equipment, net	2,516	2,670
Operating lease assets	155	262
Other assets, net	30	30
Total assets	40,203	47,675
Current liabilities
Accounts payable	612	546
Payroll related accruals	900	633
Accrued expenses and other liabilities	644	1,170
Lease liabilities, current	289	316
Total current liabilities	2,445	2,665
Accrued expenses and other liabilities, net of current portion	95	0
Lease liabilities, net of current portion	92	291
Total liabilities	2,632	2,956
Commitments and contingencies (Note 13)
Stockholders’ equity
Convertible preferred stock, $0.001 par value, 2,500,000 shares authorized; 280,898 shares of Series D issued and outstanding at March 31, 2024 and June 30, 2023	0	0
Common stock, $0.001 par value, 250,000,000 shares authorized at March 31, 2024 and June 30, 2023, respectively; 1,712,045 and 1,692,045 shares issued at March 31, 2024 and June 30, 2023, respectively; 1,701,729 and 1,681,729 outstanding at March 31, 2024 and June 30, 2023, respectively	190,643	190,643
Treasury shares, 10,316 at March 31, 2024 and June 30, 2023, respectively	(119)	(119)
Additional paid-in capital	82,277	81,002
Accumulated deficit	(234,061)	(225,354)
Accumulated other comprehensive loss	(1,169)	(1,453)
Total stockholders’ equity	37,571	44,719
Total liabilities and stockholders’ equity	$ 40,203	$ 47,675