In millions, except per share items | Jun-30-23 | Jun-30-22 | Jun-30-21 | Jun-30-20 | Jun-30-19 | Jun-30-18 | Jun-30-17 | Jun-30-16 |
| 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K | 10-K |
Current assets | | | | | | | | |
Short-term investments | 27.9 | 26.2 | 27.4 | | | 3.6 | 10.9 | 17.1 |
Accounts receivable | 0.2 | 0.1 | 0.0 | 0.1 | 0.0 | 0.0 | 0.1 | 0.2 |
Contract asset | | 0.0 | | | | | | |
|
Inventory, net: | | | | | | | | |
Raw materials | 1.4 | 0.9 | 1.1 | 0.4 | 0.2 | 0.0 | | 0.3 |
Work-in-process | 0.2 | 0.1 | 0.1 | 0.0 | 0.2 | | | 0.1 |
Finished goods | 0.4 | 0.5 | 0.3 | 0.2 | | | | 0.1 |
Income tax receivable | 0.0 | | | 0.4 | 0.4 | | | |
Prepaid expenses and other current assets | 0.4 | 0.7 | 0.3 | 0.1 | 0.4 | 0.2 | 0.3 | 0.3 |
Total current assets | 44.7 | 55.0 | 65.1 | 4.7 | 2.7 | 4.3 | 13.7 | 22.9 |
Property and equipment, net | 2.7 | 1.1 | 0.3 | 0.1 | 0.5 | 0.7 | 3.2 | 3.4 |
Other assets, net | 0.0 | 0.0 | 0.0 | 0.1 | 0.1 | 0.1 | | |
Total assets | 47.7 | 56.2 | 65.6 | 5.9 | 3.7 | 5.1 | 18.8 | 30.5 |
|
Current liabilities | | | | | | | | |
Accounts payable | 0.5 | 0.2 | 0.4 | 0.2 | 0.2 | 0.1 | 0.3 | 0.2 |
Payroll related accruals | 0.6 | 0.8 | 0.3 | 0.4 | 0.3 | 0.4 | 0.9 | 1.0 |
Accrued expenses and other liabilities | 1.2 | 1.0 | 0.9 | 0.6 | 0.4 | 0.4 | 1.4 | 1.6 |
Income tax payable | | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | |
|
Term note payable - related party | | | | | | | | |
Lease liabilities, current | 0.3 | 0.2 | 0.1 | | | | | |
Total current liabilities | 2.7 | 2.7 | 4.2 | 4.4 | 0.8 | 1.0 | 1.8 | 1.8 |
Lease liabilities, net of current portion | 0.3 | 0.3 | 0.2 | | | | | |
Total liabilities | 3.0 | 3.0 | 4.4 | 5.3 | 1.0 | 1.1 | 2.1 | 1.9 |
|
Commitments and contingencies (Note 14) | | | | | | | | |
Stockholders’ equity | | | | | | | | |
Common stock | 190.6 | 190.6 | 190.6 | 190.6 | 190.6 | 190.6 | 190.4 | 189.3 |
Additional paid-in capital | 81.0 | 79.5 | 78.0 | 13.9 | 8.0 | 1.7 | 1.5 | 1.4 |
Accumulated deficit | -225.4 | -215.7 | -207.4 | -199.8 | -191.7 | -184.2 | -170.9 | -159.1 |
Accumulated other comprehensive loss | -1.5 | -1.2 | 0.0 | | | 0.0 | -0.1 | -0.1 |
Total stockholders’ equity | 44.7 | 53.2 | 61.2 | 0.6 | 2.7 | 4.0 | 16.8 | 28.7 |
Total liabilities and stockholders’ equity | 47.7 | 56.2 | 65.6 | 5.9 | 3.7 | 5.1 | 18.8 | 30.5 |