Quarterly report pursuant to Section 13 or 15(d)

Note 5 - Stockholders' Equity (Details Textual)

v3.7.0.1
Note 5 - Stockholders' Equity (Details Textual) - USD ($)
1 Months Ended 2 Months Ended 3 Months Ended 6 Months Ended
Dec. 12, 2016
Apr. 30, 2017
May 31, 2016
Apr. 30, 2017
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Mar. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period             10 years    
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant         5,100,000   5,100,000    
Allocated Share-based Compensation Expense         $ 651,949 $ 817,067 $ 1,174,388 $ 2,287,953  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value             $ 2.99 $ 7.28  
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options         $ 1,270,000   $ 1,270,000    
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition             1 year 255 days    
Series A 4.5% Convertible Preferred Stock [Member] | Private Placement [Member]                  
Stock Issued During Period, Shares, New Issues 1,000,000                
Preferred Stock, Dividend Rate, Percentage 4.50%                
Convertible Preferred Stock, Issuable Upon Conversion of All Shares 3,887,387                
Stock Purchase Warrants [Member]                  
Class of Warrant or Right, Issued During Period     1,746,173            
Class of Warrant or Right, Outstanding         800,017   800,017    
Class of Warrant or Right, Number of Securities Called by Warrants or Rights   153,847   153,847         692,309
Class of Warrant or Right, Exercise Price of Warrants or Rights   $ 3.25   $ 3.25         $ 3.25
Stock Issued During Period, Shares, Warrants Exercised       846,156          
Class of Warrant or Right, Exercised During Period, Exercise Price   $ 3.25   $ 3.25          
Proceeds from Warrant Exercises   $ 32,500,000   $ 2,700,000          
Inducement Warrants [Member]                  
Class of Warrant or Right, Number of Securities Called by Warrants or Rights   51,283   51,283         230,771
Class of Warrant or Right, Exercise Price of Warrants or Rights   $ 5.80   $ 5.80         $ 5.80
Fair Value of Inducement Expense on Warrants   $ 87,660         $ 476,084    
Restricted Stock Units (RSUs) [Member]                  
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period             1,924    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value             $ 42.75    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Outstanding         $ 11,000   $ 11,000    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested             $ 23,000    
Stock Issued During Period, Shares, Share-based Compensation, Gross             4,939    
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Exercised             4,939    
General and Administrative Expense [Member]                  
Allocated Share-based Compensation Expense         215,980 552,930 $ 365,953 $ 1,314,400  
Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Incremental Compensation Cost           15,000   15,000  
General and Administrative Expense [Member] | Former CEO [Member]                  
Allocated Share-based Compensation Expense               407,000  
Research and Development Expense [Member]                  
Allocated Share-based Compensation Expense         $ 435,969 264,137 $ 808,435 973,553  
Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Incremental Compensation Cost           $ 42,000   $ 42,000