| Note 8 - Stockholders' Deficit (Details 2) - USD ($) | 3 Months Ended | 9 Months Ended | 12 Months Ended | |||
|---|---|---|---|---|---|---|
| Mar. 31, 2019 | Mar. 31, 2018 | Mar. 31, 2019 | Mar. 31, 2018 | Jun. 30, 2018 | Jun. 30, 2017 | |
| Allocated Share-based Compensation Expense | $ 1,086,000 | $ 45,000 | $ 1,492,000 | $ 209,000 | $ 255,000 | $ 40,000 | 
| Research and Development Expense [Member] | ||||||
| Allocated Share-based Compensation Expense | 225,000 | 16,000 | 256,000 | 80,000 | 96,000 | 13,000 | 
| General and Administrative Expense [Member] | ||||||
| Allocated Share-based Compensation Expense | $ 861,000 | $ 29,000 | $ 1,236,000 | $ 129,000 | $ 159,000 | $ 27,000 | 
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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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