Note 7 - Stockholders' Equity (Tables)

3 Months Ended

Sep. 30, 2018

Notes Tables

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

	Weighted Average, September 30, 2018			Range, September 30, 2018			Weighted Average, September 30, 2017		Range, September 30, 2017
Volatility		70	%	63%	-	76%		-		-
Dividend yield		-			-			-		-
Risk-free interest rate		2.73	%	2.68%	-	2.78%		-		-
Expected term (years)		3.9		3.4	to	4.3		-		-

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, 2018		6,827,225	$	1.11		3.8	$	-
Granted		325,000		0.68
Exercised		-		-
Forfeited		-		-
Expired		-		-
Outstanding at September 30, 2018		7,152,225	$	1.10		3.8	$	-
Exercisable at September 30, 2018		7,002,225	$	1.11		3.8	$	-

Schedule of Nonvested Share Activity [Table Text Block]

	Options			Weighted Average Grant-Date Fair Value
Nonvested at July 1, 2018		-		$	-
Granted		325,000			0.36
Vested		(175,000	)		0.46
Nonvested at September 30, 2018		150,000		$	0.25

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

	Three months ended September 30, 2018		Three months ended September 30, 2017
General and administrative:
Fair value of stock/warrant bonuses expensed	$	-	$	4,133
Change in fair value from modification of option terms		211,185		-
Change in fair value from modification of warrant terms		118,233		-
Fair value of stock options expensed		69,625		2,300
Total	$	399,043	$	6,433
Research and development:
Fair value of stock bonus expensed	$	-	$	7,027
Change in fair value from modification of option terms		11,115		-
Change in fair value from modification of warrant terms		44,793		-
Fair value of stock options expensed		25,875		-
Total	$	81,783	$	7,027