Note 8 - Stockholders' Equity (Tables)

12 Months Ended

Jun. 30, 2018

Notes Tables

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	Weighted Average, June 30, 2018	Range, June 30, 2018			Weighted Average, June 30, 2017	Range, June 30, 2017
Volatility	74%	68%	-	75%	78%	73%	-	86%
Dividend yield	-		-		-		-
Risk-free interest rate	2.44%	1.75%	-	2.64%	1.17%	0.82%	-	1.44%
Expected term (years)	5	3	-	6	3.9	3	-	4

Share-based Compensation, Stock Options, Activity [Table Text Block]

	Options			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life		Aggregate Intrinsic Value
Outstanding at July 1, 2016		4,225,537		$	1.45		4.1	$	158,675
Granted		319,500			0.97
Exercised		-			-
Forfeited		-			-
Expired		-			-
Outstanding at June 30, 2017		4,545,037		$	1.42		2.9	$	176,575
Granted		2,647,500			0.76
Exercised		-			-
Forfeited		-			-
Expired		(365,312	)		2.35
Outstanding at June 30, 2018		6,827,225		$	1.11		3.8	$	-
Exercisable at June 30, 2018		6,827,225		$	1.11		3.8	$	-

Schedule of Nonvested Share Activity [Table Text Block]

	Options			Weighted Average Grant-Date Fair Value
Nonvested at July 1, 2017		25,000		$	0.46
Granted		2,647,500			0.52
Vested		(2,672,500	)		0.51
Nonvested at June 30, 2018		-		$	-

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]

	Year ended June 30, 2018		Year ended June 30, 2017
General and administrative:
Fair value of stock/warrant bonuses expensed	$	8,723	$	15,021
Change in fair value from modification of option terms		243,761		166,031
Change in fair value from modification of warrant terms		163,956		-
Fair value of stock options expensed		782,135		129,081
Total	$	1,198,575	$	310,133
Research and development:
Fair value of stock bonus expensed	$	15,098	$	22,084
Change in fair value from modification of option terms		105,895		11,440
Change in fair value from modification of warrant terms		132,896		-
Fair value of stock options expensed		587,215		23,252
Total	$	841,104	$	56,776