Note 10 - Stock Option Plan (Tables)

9 Months Ended

Sep. 30, 2014

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

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

	Outstanding Options
						Weighted-
				Weighted-		Average
	Number			Average		Remaining
	of			Exercise		Contractual
	Shares			Price		Term (years)
Options outstanding as of December 31, 2013		363,413		$	2.94		8.80
Options granted		1,901,476		$	0.60
Options assumed from PLC		68,238		$	10.24
Options canceled		(38,593	)	$	1.75
Options outstanding as of September 30, 2014		2,294,534		$	1.02		9.67

Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table Text Block]

			Options Outstanding						Options Exercisable
							Weighted-
			Number		Weighted-		Average		Number		Weighted-
			Outstanding		Average		Remaining		Exercisable		Average
Range of			as of		Exercise		Contractual		as of		Exercise
Exercise Prices			September 30, 2014		Price		Term (Years)		September 30, 2014		Price
	$0.12			320	$	0.12		2.21		320	$	0.12
	$0.60			1,901,476	$	0.60		10.00		20,000	$	0.60
	$1.24			314,036	$	1.24		8.15		314,036	$	1.24
$7.00	-	$9.00		59,372	$	8.63		8.28		59,372	$	8.63
$12.00	-	$18.63		19,081	$	15.29		6.79		19,081	$	15.29
	$37.00			250	$	37.00		3.72		250	$	37.00
				2,294,535	$	1.02		9.67		413,059	$	2.94

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

	Nine Months Ended
	September 30,
	2014		2013
Expected term (in years)		5		5
Average volatility		61%		67%
Risk-free interest rate		1.80%		0.87%
Dividend yield		0%		0%

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

	Three Months Ended September 30,				Nine Months Ended September 30,
	2014		2013		2014		2013
Research and development	$	101	$	976	$	667	$	(7,016	)
General and administrative		113,245		15,308		142,976		73,017
Total	$	113,346	$	16,284	$	143,643	$	66,001